Charles' and Rick's Ultracruiser

By the river

2011-07-03T15:39:00.004-04:00

We have registered the Ultracruisers now and are flying off our 40hrs. I finished the first polish pass on mine and we hope to have Rick's done soon as it is such an embarassment to fly with an unpolished UC :)
I am also designing and soon to be testing a secondary Magnetron-based ignition system.

Building Ends, Flying to Begin!

2010-04-24T15:19:00.006-04:00

Build Hours: 1263

Both UCs are complete as much as a homebuilt ever will be.

The 32hp UC on the left has flown but the pilot was suffering sensory overload.

A full flight report will be posted in the future.

Rick's Panel

Below the panel - Notice the parking brake nob, heel brakes and absense of clutter around the feet.

Charles' Panel

Rick's 37 hp Cassler Engine with Slick mag, 54X22 Tennesse prop, 3250 static rpm with 175 lbs thrust. Both engines are instrumented with oil temp, oil pressure and a Tiny Tach.

Charles' 32 hp Cassler Engine with Fairbanks-Morse Mag, 52x22 prop, 3050 static rpm with 140 lbs thrust.

Wing Tip

2009-12-03T08:29:00.003-05:00

Build Hours: 1101

A few preparations for installing the wingtips.

Set the spacing on the wingtip aft rib.

We made a pattern from 1/4" Luan plywood the followed the wing rib profile. The plans pattern did not line up properly. The angles were also used to make sure we didn't droop the skins in the process.

As always, a form is needed for forming the tip.

The first attempt was a form without flute positions. We formed the edges, removed the tip and then began the fluting process. The outcome was a very warped tip with unsightly fluting depressions.

The second attempt was to notch and bend the tip. The notches made the tip very floppy and difficult to fit and peaked out from under the skins at every opportunity.

We had the best success with the third method. We made fluting positions every inch around the form (except on the bottom from the spar position back). With the tip formed and fluted, it is much easier to fit.

(Add tip skinning and finish pictures here!)

Weighing the completed wing - tip and aileron attached - 29lbs.

Ailerons

2009-11-16T19:08:00.005-05:00

Build Hours: 1080 Hrs.

Aileron Folding

One set ready for final fold.

Dowell to finish fold around.

Dowell taped in place.

When only the best equipment will do - a 2x4 hinged to the workbench.

Installed! Now wasn't that easy?

Wing Construction

2009-11-16T19:00:00.007-05:00

Build Hours: 1080 (we're sloooooow)

Support the ribs while skinning.

Use the vacuum method to preform the nose skins.

Wrap fit and trim

The shop is maxed out!

A worm gear drive winch allows the planes to be swapped as needed or this is the beginning of The World's Smallest Airplane Museum.

Picture Day

2009-07-21T19:36:00.003-04:00

Build Hours: Don't Matter

Rick

Charles

Tailsprings, Brakes, Pitot, Throttle

2009-07-21T19:01:00.010-04:00

Build Hours: 997

Vacations and summer lethargy has slowed the progress. We have been finishing some of the details that are not covered in the plans. When the throttle and choke assemblies are routed into the engine compartment and the pitot is installed we will be back to the outboard wing sections.

This is a 3/16" plywood seatpan that keeps the spar from digging into the back of the legs.

We modified screen door springs from the Lowes Aircraft Dept. for the tailwheel springs. The springs allow some give if you touchdown with rudder input and with the springs in compression there is less chance of breakage.

This blurry little bracket was riveted in the rib corner of the 3 inner ribs to hold the brake cables in place. It would have been much easier to do this before skinning the wing:)

Example of the brake cable bracket installed. The pitot and static lines will be tie wrapped to the brake cable.

Brake cable entering wing.

This is the right brake.

...and the left brake.

This floor pan allows your feet to rest without sliding to the fuselage center bottom. The heel brakes seem to work well.

This is the parking brake assembly. Rotating clockwise approx. 8 turns will lock the brakes. A doubler was added to help the bulkhead take the brake cable loads.

This is the pitot-static tubes. Spruce sells a similiar setup but we had some 1/4" tube and a lathe sitting idle so...

The throttle and choke control is still a work in progress.

Wing Center Trims

2009-05-06T21:13:00.008-04:00

Build Hours: 917

The trims are a real challenge. We can't decide if we should admire Morry (the designer) or shoot Morry for creating these nice fairings. They are a real metal working challenge and we are still working on the front trim.

Plan Note: The plans indicate 6061-T6 for all of the trims. The front trim requires too much stretching to made from 6061-T6 IMHO. My hat is off to you if you made your trim from 6061!. We are trying 6063-T52 from Lowe's right now and Rick has had some success wrestling it into shape. We may have to back down to 5052-T4 or 3003 from Spruce/Wicks before the trim is completed.

Top Rear Trim

Top Middle Trim

Top Front Trim

Bottom Trim Installed

Top Trims Installed

Wing Center Trailing Edge

2009-05-06T20:53:00.008-04:00

Build Hours: 901

We have completed the center section trailing edges. The trailing edge ribs were cut according to the plans but had to be adjusted to fit our rear spars by about 3/32"

Next, the required pattern was made for the trailing edge skins.

These are the original cuts we made to finish the inside edges. Later, more material had to be removed to allow the bottom trim to lay as flat as possible. The trailing edge, trim and fuselage do not lay in the same plane.

The installed trailing edges.

Wing Center Skinning

2009-03-22T18:50:00.015-04:00

Build Hours: 865

Lots of hours were involved in completing one of the UC wing center sections. There's a lot of missing steps in the next sequence of pictures which I hope to fill in as we complete the center section on the other UC. Now that we've gained some "prior building experience", we'll know when its a good point to take a picture.

Some of the pictures are dark due to me bouncing the camera off of the concrete floor which killed the flash, arghhh!

The UCSide

(kinda like the popular cartoon - The Farside without as much humor:))

"The intrepid builder realizes too far into the project that the cockpit is rather snug!"

As always, we started with a pattern. During the entire nose skining process, we kept the fuselage level and the wing spar plumb by clamping the rear spar to a 1" x 2" steel tube clamped to the siderails. Level and plumb was checked often!

We use the offset pen/pencil to follow the fuselage shape.

We used the vacuum bagging method to form the nose skin around a 2" pipe.

Here the skin is being trial fit.

After the nose skin, which required lots of strapping and adjustments, we installed the top aft skin. We then flipped the fuselage to fit the bottom skin. The extra rib and reinforced ribs are for the wing step area.

This is the gear leg in place under the wing.

This is the gear leg attached to the spar and the aileron bracket.

This picture shows the shape of the rear spar and the aft skin fit. this will all be covered by the wing fairings when completed.

The wing step has an additional .040 panel to stiffen things up.

Another view of the rear spar and lower skin attachment.

The rectangular riveted section is the landing gear doubler.

Controls and Wing Center Section

2009-01-15T09:58:00.011-05:00

Build hours: 769

The control system, seat back, seat brace, center spar installation and spar braces have been completed for UCA and UCB.

These are the rudder pedals purchased from Hummel as part of the controls kit. The aluminum welding made our decision to purchase. The lightening holes in the rudder bracket is a recommendation from Hummel that is not on the plans (4 oz). The wimpy looking brace makes for a very solid arrangement.

Plan note:

The lower tab on the brace is too long and flexes to much to be effective per the plans. One builder put a rivet in the tab behind the bolt. We remade the bracket and shortened the tab.

Nylon washers, 1.25" in diameter , .125" thick were placed on each side of the rudder bar for a good fit and smooth rotation.

This is a closeup of the front of the middle rudder pushrod link.

The next link in the rudder pushrod was bowed against the fuselage for maximum arm/elbow clearance.

This picture shows the middle to rear rudder pushrod link attachment. Four threads were left showing on the rod ends for adjustment.

Also show is the placement of the seatback support. The support was put under the rails so that the canopy fit would not be interfered with. Some felt or nylon needs to be added where the seatback rest against the support.

The control stick was curved to better align with the hand. Some trimming of the pre-welded assembly was required to get the stick and horn to center appropriately. Also, 2 assemblies were purchased, one was welded per the plans, one was welded per the welder - someone always knows better than the designer.

Plan note:
The first elevator pushrod link requires an unusual bend to miss your leg and enter the "C" bulkhead correctly.

We made several trial pieces, bent a disaster, walked away, came back and ended up with "perfection":) (And we did it correctly twice!)

The rear bulkhead openings and horns were made a long time ago... Its great when the plan comes together!

The rudder and elevator shouldn't have to be removed so the safety cotter pins were installed, and all horizontal stab bolts were tightened and indexed with a red paint mark.

The inserts for all of the control rods were turned , bored and tapped on the lathe. Only 16 more to do for the aileron pushrods.

The seat was bolted to 2 pieces of angle attached to the bottom rails.

This is the "C1" buckhead. Notice the misaligned centering marks. The error was caught after the picture but before we screwed up :)

Ribs and Spars

2008-11-26T08:40:00.017-05:00

Build hours: 697

Progress has been made since the last update in August. We decided to build our ribs for the experience, weight savings and to use up all of the accumulated cutoffs instead of buying 2 additional 4' x 12' sheets. So far, the rights side ribs and spars are completed and the left side rib parts are made.

This is the particle board jig to hold the rib parts in place during assembly. The top and bottom caps were bent in the brake and then shrunk to the rib pattern. An endless number of braces were folded (enough for 2 sets of ribs).

Alignment dowels were inserted into the jig to allow the pattern pieces to be moved to the opposite side of the build board to make left or right ribs.

A form was made to bend the nose pieces over and a particle board flanging die made to make the lightening hole flange. Shrinking of the flanges manually and with the shrinker was required.

Finished rib assemblies.

We used 3/32" solid rivets to assemble the ribs. After you get the rivet driving going, its as fast as pop rivets and gives better edge distances.

These are the 4" or 4 1/2" flanging dies for the spar lightening holes. The flanges stiffen the web considerably even though all of those holes only remove 3.7 ounces from each spar.

A 14' jig was made that would hold the spar center section and one outer spar at the correct angle. The spar fittings were prepared and clamped. The jig was set at the correct height for the drill press. All spar fitting holes were drilled undersized and reamed to .002 or .001 under as required.

Additional rounding and cleanup on the spar fittings was completed. All spars are done.

Spar braces

2008-08-16T16:24:00.010-04:00

Build hours: 577

The spar has been positioned and attached temporarily to the bottom angle. The outer spars have to be made and matched to the center spar before the center spar can be fastened permanently. The spar braces were made and ready to rivet. The edges of the spar braces were rolled over to give a more finished look and provide additional stiffness in the process.

The spar brace edge required notching to set on the spar caps.

This shows the spar brace bend angles required to match the fuselage and the bend on the outer edge. The blank had additional width for bending in the brake. After bending, the extra material was cut back.

The wooden brake works well for aluminum up to .025 and even short pieces of .040 but it was not up to the task of bending .062 2024T3 across the grain. A 17" brake made from leftover 1/8" steel angle was cobbled together. The platten has a 3/16" radius which is required when bending .062 2024 in the T3 condition (3X thickness).

Center Spar

2008-07-20T20:13:00.014-04:00

Build Hours: 542

The spar is labor intensive and the plans require a lot of study to catch all of the details (hope we didn't miss any)! We finally found the answer to "Where's the beef?" - it's in the center spar.

This is the spar cutout. An air nibbler was used for the bulk of the cut. Shears were used to clean the straight cut lines and a drum sander was used for the large radius. Lots of filing and sanding completed the cutout.

These are 2024 T3 3/16" blanks cut from the carry thru stock. The stock plate was cut with the grain in 1 1/16" strips with a jigsaw and then put in an X-Y vise. A 1/4" endmill was used in the drill press to square the blanks to 1". The 2024 aluminum is really hard on jigsaw blades and 10 tpi was found to do the best job.

Here's the center web with the spar tangs and upper and lower caps. The caps have already been notched and the tangs have been radiused. The other 2 pieces are the cap spreader and spacer.

The assembled end of the spar ready for riveting. The end cap notch radius has been carefully sanded up to 800 grit and polished. The last 4 holes for the tang bolts will go to the drill press for drilling and reaming to get the best fit. The outer spars must be built next to set the dihedral and complete the spar tang drilling.

The carry thru was cut per the plans with a jigsaw. The plate was cut across the grain. A holesaw in the drill press was used for the lightening holes. More filing and sanding to cleanup the edges!

The web stiffeners were bent in the homemade brake after a modification to the platen for the 1/2" channel width.

Panel, Vents and more...

2008-06-25T20:06:00.022-04:00

Build hours: 521

The tanks held 5 gallons with breathing room and DID NOT LEAK!

Ventilation is provided by two 2" snap vents. The vents do not close but very little air comes in in the down or back position. The vents do a good job at directing the air to the face or torso - we used the air compressor to check.

The instrument panel was made from .040 6061 per the plans which makes a very light panel. The panel was flanged to stiffen it and Cessna style shock mounts are used to mount and isolate from the airframe. A gap was left around the panel to allow it to move on the shock mounts.

Seatbacks were formed so that all of the square tube bending would be completed.

The fuselage is leveled laterally and longitudinally and a solid reference is mounted to align the wing spar.

The level was on sale at Sears for 25 bucks. Its very handy and builds your confidence in the accuracy of a bubble level.

Preparation for the big cut. A line is drawn across the bottom of the fuselage, 14" from the back of the B bulkhead and one down the centerline to align the pattern on.

Plan note:

Call Hummel to get an Autocad drawing of the pattern if you didn't get the kit and consider moving the line back if you a big fella!

Windscreen and Canopy Done! Moving on...

2008-06-01T10:55:00.010-04:00

Build hours: 509

Here's an update for Louise... (see previous comments)

The bows are bent. The canopy and windscreen are in place. The windshield trim is formed and the latch latches. The tank cover is in place and the instrument panel is being planned. Moving right along...

Windscreen

2008-04-25T07:44:00.002-04:00

Build hrs: 483

The bows for the front windscreen were bent to match the front canopy bow - we're getting better at bow bending. Also, we started making a pattern for the instrument panel skin.

Canopy

2008-04-12T19:34:00.006-04:00

Build hours: 477

A busy work schedule has slowed progress but here is an update on the canopies. Make sure you go all the way to the last picture.

The rear bow allowed us to match the turtledeck but it was difficult to get the shape right.

The trim molding seals the canopy for flying the mission in inclement weather.

The canopy latch has an outside handle.

The handle is made of 3/8" 6061T6 tubing and attaches through the pivot arm with a roll pin. The cotter pin is just temporary.

Canopy #2 - It happens.

Canopy

2008-03-23T17:08:00.006-04:00

Build hours: 458

UCB's canopy frame is coming together and the turtledeck is in place. The canopy was harder than expected and the turtledeck flange and fitting was easier than expected. We added a rear bow to the canopy (6 oz.), made a flush joint on the side panel instead of the overlap and are just generally pleased with our progress. Now, if we can just remember how the canopy came together so that we can repeat on UCA.

Canopy frame

2008-03-07T21:46:00.012-05:00

Build hours: 449

Plan note:

Don't do anything to the canopy area without the canopy. Almost every dimension on the canopy bow and canopy installation plan sheets appear to be more of a suggestion than actual working dimensions:(

Picture: Chuck Yeager checks canopy fit

There are lots of angles and dimensions to be monitored during the canopy/windscreen/turtledeck construction. We finally decided to clamp up the frame and canopy on the plane and then tweaked and adjusted until we had an acceptable fit. More to come as we continue the canopy building. The UC is really starting to shape up!

Gas Tank

2008-03-07T21:05:00.010-05:00

Build hours: 436

In the last working post, we decided to order and wait for the canopies to arrive before continuing. While waiting, we decided to build the fuel tanks using leftover .016 6061 aluminum and pop riveted construction. Inspiration came from

http://bobhooversblog.blogspot.com/2006/12/av-yo-fuel-tank.html.

Thanks Mr. Hoover!

Plywood/particle board forms for the tank front and back bulkheads were made from the plan layouts and the tank front and back were formed with 1/2" flanges. The tank bottom was cut out and bent per the plans. The tank parts weigh 1.25 lbs - which should be 1/2 the weight of the .032 5052 welded tank. Total cost was less than $95 dollars per tank.

Plan note:
Check the front and back bulkhead forms for proper clearance under the skin (approx 1/4" allows for padding under the tank on the rails and over the tank top under the skin) . The first rear tank bulkhead came out against the tank skin and the form had to be adjusted and the bulkhead remade.

After forming, the bulkheads were clecoed to the bottom. The front bulkhead flanges were turned in and the rear bulkhead flanges were turned out to accomodate the flange angles after forming an the tank slope. The tank top template was fitted and trimmed. The tank top was then cut, drilled and clecoed. One inch rivet spacing (117 total) was used and the rivet holes were dimpled to accept AAC rivets. The tanks will be completed by using red ScotchBrite and MEK or Alumiprep etching to clean the rivet lines and a generic ProSeal Epoxy from Van's Aircraft to seal the tank. No sloshing required!

An aluminum filler flange was found online from

http://www.speedwaymotors.com/p/4270,58_Filler-Neck-Twist-Cap-with-Aluminum-Flange.html

and an AN867-3 was used for the outlet. The AN867-3 flange required turning on a lathe to remove the turned up edge and provide a wider flange.

Engine candidate

2008-02-20T20:41:00.004-05:00

A 32hp 1/2 VW came across Barnstormers so it was purchased with the optimism that eventually there will be a completed UC to hang it on, otherwise it becomes an addition to this fancy aluminum planter we're working on! The shipping crate will be turned into a temporary engine stand so the engine can be run and checked for leaks, performance, etc.

Canopy frame

2008-02-20T20:17:00.007-05:00

Build hours: 422

The plans note that JB Weld can be used to fill in cupping caused during bending. Filling the tubes with sand seemed to eliminate any cupping. and also prevented any tendency to kink or collapse the tube. Also, bulkhead E was used instead of bulkhead F (per the plans) to produce a smoother radius.

We are now waiting on the canopies before proceeding.

Plan note:

The canopy bows should not be bent or cut without the canopy on hand. There are several dimensional disrepancies in the plans (surprise!) and the bow patterns are too short. Oh well, always remember - PBER (Prior Building Experience Recommended) - or ohcrap for short!

Control horn and tailwheel welding

2008-02-03T16:02:00.000-05:00

Build hours: 416

Logging more build hours. The welding is done so all that is left to the control horns and tailspring is to bead blast and paint!

Finished the painting and here they are!

Control horn and tailwheel welding

2008-01-29T09:00:00.000-05:00

Build hours: 396

After two evenings and a full Saturday, we have finished the rudder control horn, tailwheel drive on the bottom of the rudder control horn and the tailspring with tailwheel. A 3/16" rod was inserted through the rudder control horn and hinge brackets to align the pivot points. Hopefully the welding will be completed this week and some pictures of the completed and painted brackets will be posted.

Plan note:

1) There is not much clearance above the tailspring for the tailwheel drive at the bottom of the rudder post so plan the tailspring bracket welding carefully or the rudder travel will be limited.

2) The drawing for the tailwheel bracket is so wrong! Could Hummel not make some updates to there website with a few new notes? The arms are not long enough for the 4" tailwheel and do not provide enough clearance for the tailcone so don't waste the metal! We lengthened the arms and added a down angle that provided an additional 1" of tailcone clearance.

Control horns

2008-01-21T22:12:00.000-05:00

Build hours: 383

Finished welding the control arms on the elevator control horn and welded the upper and lower post for the rudder control horns.

Elevator control horn

2008-01-19T21:58:00.000-05:00

Build hours: 379

We practiced welding tubes to sheet steel for several hours on Saturday. Rick's skill improved more quickly than mine so he became the designated welder. After attempting to twist, tear or bend the welded tubes off of the steel sheet , without success, we were ready to weld the elevator bracket. The bracket parts were aligned on the elevator, tacked and then moved to the workbench for final welding. The bracket required some adjustment due to distortion caused by the welding but it was definitely air-worthy.

More tail feathers...

2008-01-17T21:45:00.000-05:00

Build hours: 372
Sorry, I'm just logging the hours so there are no new pictures. Refer to the prior tailcone, rudder and elevator pictures to jog your memory!
The tailcone, elevators and rudder was completed and installed on the other UC.

Rudder 2

2008-01-07T21:15:00.000-05:00

Build hours: 363

We're back on the job after a holiday hiatus. The rudder was rebuilt and looks great. A tally of the material cost to date is approx 1K for each UC. The UCs will be swapped again to complete the other control surface installations and then we'll try our hand at gas welding the control horns and tailwheel bracket.

Rudder 1

2007-12-22T16:20:00.000-05:00

Build hours: 357

Sometimes things workout (see tailcones) and sometimes they don't. The rudder with the rounded leading edge looks great but we slipped up and built a twist into the rudder just like the plans warn. A new spar and ribs have been manufactured and as soon as some new skin material arrives we will replace the rudder and move forward.

Tailcone

2007-12-16T08:51:00.000-05:00

Build hours: 345

Just spent an entire work session forming the tailcone. Four cardboard patterns and 1 aluminum trial and we're still fidgeting with it. We're attempting to create a pinched tailcone instead of the normal "jet exhaust" tailcone.

After taking a break, the final tailcones were made. Here are the pictures of the end result.

The tailcone model or which end is this?

Elevator hardware

2007-12-06T21:41:00.000-05:00

Build hours: 333

Rough skins for the remaining elevators were cut and flat 4130 parts for the elevator and rudder control horns were cut.

Elevator construction

2007-12-05T21:19:00.000-05:00

Build hours: 332

There is not a layout for the elevators in the plans!?

A rough skin for the elevator, with plenty of excess, was layed out and trimmed from a sheet of 6061 .016. The center line was folded as far as possible in the brake and then moved to two hinged 2"x4"s to complete the bend. An 1/8" wooden dowel was taped into the crease to maintain the bend radius before closing the bend in the 2"x4"s. The ribs were riveted to the top with temporary aluminum rivets then the elevator was flipped and the skin was drilled for the other side of the ribs. The skin was marked at the rib ends returned to the brake again for the hinge flanges. The flanges were temporarily riveted. The elevator was positioned on the stab an the hinge halves were taped to the elevator with strapping tape. The hinge pins were removed and the elevator was drilled for the hinges.

The elevator can be simple to construct as long as you base the construction on the top of the elevator otherwise the angles and taper can get you!

Plan note:

The plans suggest using a shim under the outboard rib of the elevator during construction to avoid building a twist into the elevator. The kit manual mentions building on the top and use some temporary alumium rivets during the construction. The temporary rivets is much easier.

Horz stab completion

2007-12-04T14:09:00.000-05:00

Build hours: 321

The horizontal stabs are complete. This shows the elevator hinges being aligned with a steel wall stud.

A piece of .062 lexan was used for the 2.5" inspection holes. 6-32 nutplates were riveted to the lexan to secure the inspection plate. By removing 3 screws and loosening the fourth, the inspection plate can be rotated for access to the stab bolts. The lexan covers were installed before closing but could have been rolled and inserted through the hole at a later time.

Horz stab skinning

2007-11-30T08:14:00.002-05:00

Build hours: 315

The UCA tail is now hanging from the rafters waiting for the lexan inspection plates to be installed before final closure. The UCB tail is installed and drilled awaiting cleanup, and inspection holes. The UCB tail has taken half the time and a fourth of the struggle to complete since we have the experience from UCA! A few steps in the manual could have made it all a lot more painless. I do not recommend building the tail on the plane but the alternatives suck too.
The clamps pictured below are cheap and easy and greatly simplify the skin installation. Some light spring clamps on the trailing edge will hold until the skin is positioned.

Here are five items to watch for when constructing the tail -
spar level
correct incidence
inboard edge fit
outboard edge square
spar pucker
Check each item and often during the fitting.

Plan note:

The basic steps (which the kit guide doesn't mention, (falls under - should have prior building experience)) are:

1) Mark all flange centerlines before assembling the spars and ribs on the fuselage. Extend the forward spar centerline onto the fuselage and onto the outside of the outboard rib.
2) Install the rough cut skin as pictured and clamp. (Check the 5 items).
3) Use a guide to create the fuselage trim line

4) Remove the skin and trim the fuselage line.

5) Reinstall the skin (Check the 5 items). Mark the ends of the forward spar on the skin. Mark the trailing edge trim line. Mark the outboard rib trim line.

6) Remove the skin. Trim the trailing edge and outboard edge. Mark the spar rivet lines top and bottom, front and rear. Mark the rivet pattern on the inboard rib. Measure and record the distance from the inboard rib rivet to the fuselage and record it on the fuselage.

7) Reinstall the skin (Check the 5 items) . Mark the inboard rib rivet pattern using the recorded distances.

8) Drill and cleco several inboard rib holes top and bottom (Check the 5 items).

9) Push or pull the forward spar to align the flange line and procede to drill every 3rd or 4th hole to the tip (Check the 5 items).

10) Mark and drill the top trailing edge (Check the 5 items) and bottom trailing edge every 3rd or 4th hole. Drill the outboard rib top and bottom and then complete all drilling.

11) Go to bed - you've been at this for a long time!

Horz stab skinning

2007-11-21T21:22:00.000-05:00

Build hours: 297

The UCA stab only needs inspections holes, cleanup and final riveting. The stab skins have taken a surprising amount of work with a lot of attention to plumb, level, square etc. It is also made more difficult by having to build and skin on the plane which requires a lot of inverted work. The actual steps will be documented on UCB.

Horz. Stab Skins

2007-11-16T08:33:00.000-05:00

Build hours: 286
Well, a quick post about stab skins. After installing a stab skin, your are qualified to be a one-armed wallpaper hanger. We have not actually completed a skin yet but here's a quick clip on vacuum forming.

Horzizontal Stab Spar

2007-11-12T23:30:00.000-05:00

Build hours: 281

The patient has been moved to a clean room environment for appendage attachment.

Actually, we were getting tired of seeing our breath when working in the unheated shop so a 12x16 enclosure was arranged with a 5400W electric heater so that we can work in comfort through the winter months. Each UC will be positioned through the enclosure as needed. The fuselage has been clamped level across the rails so that the stab can be aligned without worrying about the fuselage moving even though we still do a paranoid check regularly:)

The tail spar was built and bolted to the inboard ribs. The 1x2 is used to stiffen the spar in the fore and aft direction while positioning the outboard rib and preparing for the skin. A prop protractor was set for the -3 degree incidence angle and used to check the angle from the inboard to the outboard end.

Note:

The plans reference the dimension from bulkhead "F" to the rear of the stab spar as 2 3/4". When ours came out to 3 1/4" we were "concerned". A call to the factory confirmed that the 3 1/4" measurement was correct and that the 2 3/4" measurement was based off of the center of the inboard rib rear bolt hole instead of the bulkhead!

Also, an AN-6A bolt was substituted for the AN-7A bolt called for the rear hole on the inboard rib. The AN-7A would have bottomed in the nutplate without too many additional washers.

Vertical Stab Dorsal Fins

2007-11-08T10:55:00.000-05:00

Build hours: 277

Both dorsal fins have been installed. The steps were posterboard pattern, metal template, vaccuum formed radius, particle board form blocks, flanging, shrinking, drilling, deburring, riveting, ADMIRING!

Note:

Some of the rivet stems in our latest batch of Avex rivets have been breaking above the rivet. This may be due to the thinner materials being riveted or inconsistency in the Avex "non-structural" rivets. Either way, when the stem breaks above the rivet, the formed head is opened like flower petals. In the tail area, this has been happening approx. 1 out of every 30 rivets requiring the rivet to be removed and replaced.

After the dorsal fin high, we moved on to kitting the horizontal stab. The outboard ribs were shaped over form blocks with a small amount of shrinking work and all of the spar components were formed up in the break.

More formation flying

2007-11-02T08:16:00.000-04:00

Build hours: Who cares!

Coming:)

Going :)

Vertical stabs completed

2007-11-01T07:30:00.000-04:00

Build hours: 272

The top rib and forward spar were positioned. The lightening holes were left out because the weight removed is negligible (see weight calc below), stiffening is minimal and warping during flanging is almost guaranteed!

Weight calc = Holes * pi * radius^2 * thickness * lb/in^3

lbs = 14 * 3.14 * .75 * .75 * .016 * .1

lbs = .04

ounces = .63!

Top rib installed.
Here the skin is clecoed into position for the final riveting. The skin was vacuum formed instead of "carpet formed" as described by Bill Spring and Morry. We hated to break tradition but after seeing the Sonex guys form their wing leading edges on YouTube?? we had to try it. A short video clip will be added later when the horizontal stab skins are made but we had so much fun forming the vertical stab skins that we couldn't stop:)!

The process was - make a rough pattern from poster board, cut out a skin blank, tape the rear edges together, wrap with 4mil plastic, seal one end and stick the shop vac hose in the other and seal. Finally, hit the switch, and before you can say oh crap, the skin is formed and ready for fitting. The process is easy and repeatable.

Notes:

1) Cut your skins with the grain running in the same direction. The skin is stiffer and will form a different leading edge across the grain than with the grain.

2) The empennage skins do not require a mandrel since the skin stiffness stops the bend with a nice radius.

3) Clamp the skin on the vertical stab spar as plumb and true as possible checking alignment from every angle possible! Then, mark a line approx. 1/8" up on the bottom edge with a guide against the fuselage (just like Norm would do on This Old House:)). This will give the skin a good fit with the least amount of effort.

And here is the final product. The top rib has not been riveted so that the refuge from installation of the dorsal fin (coming next) can be dumped.

Bottom rails, vertical stab

2007-10-27T07:10:00.000-04:00

Build hours: 262

The bottom rails were drilled, deburred and riveted to the fuselage bottom. The area around the spar was left open until the actual spar bolt locations were drilled.

Many of the empennage parts had been precut in between other building task and were ready for forming. The obligatory particle board form blocks were cut, smoothed, rounded, etc and the rib were carefully formed. Of course, with the curved flanges, the parts came out of the forms with ripples in the flanges and curved like a banana :( It was finally time to use the shrinker. A few soft presses straightened the part and we drilled and clecoed the ribs to UCA and UCB.

"A" Bulkhead stiffeners

2007-10-26T07:09:00.000-04:00

Build hours: 252
The "A" bulkhead stiffener was added. The bulkhead tabs were drilled, the stiffener clamped and then backdrilled 3/32". The holes were then drilled with a 1/8" drill instead of a #30 in preparation for dimpling. The holes were deburred and dimpled and then the stiffener was riveted on. The stiffener was placed so that 1/4" turn fasteners could be installed in the front edge in their streamlined position and #6 nutplates could be installed in the rear edge.

Engine compartment completed

2007-10-22T14:37:00.000-04:00

Build hours: 244

Both engine compartments are riveted up and ready for the engine cover. The lower engine baffle and braces are under the skin for a smoother look. The nose cowl hole and slot is flanged and the engine cover will lay flush on the nose cowl ledge. The nose cowl will not be riveted until the engine can be test fit and the oil cooler baffle can be installed. Plan note:Our next step is to flush rivet every other hole on the side rails back to bulkhead "B" and add the angles to the bottom of the fuselage before retiring to some tail work!

Plan note:

We intended to flush rivet every other rivet on the siderails between bulkhead "A" and "B" per the plans. The plans do not mention the need to countersink the rail holes so that the skin can be dimpled for the flush rivets which would need to be done before installing the rail! (The catchall plan note is - prior building experience is required!) With only the rivets in the C to D skin needing removal, we could have accomplished the countersinking. However, a call to the factory suggested using the universal head rivets and then relieving the tank cover skin for those rivets. This is simpler and allows the entire rail to have a 1" rivet pattern showing.

Engine compartment

2007-10-07T19:47:00.000-04:00

Build hours: 230

Disassembled, deburred and reassembled both engine compartments. (The deburring fingers are now experiencing a minor numbness!) The front cowls need to be formed and the engine compartments will be ready for riveting! The next view of the engine compartment will be less prickly.

Engine compartment

2007-10-06T19:32:00.000-04:00

Build hours: 224

The front cowl needs a hole for the engine thingy to go through and a few air holes to keep the engine thingy cool. A hole is not complete without a flange so after some masterful routing and a mess of particle board dust in the shop these dies were created for flanging.

The first hole and slot in the test cowl was done by hand with the Morry stick method (labor intensive) and the last slot was made with the die with a few whacks from the deadblow.

Engine compartment

2007-10-05T19:14:00.000-04:00

Build hours: 218
Job and scheduling interfered with the important things of life but we are back and moving on the engine compartment. The side braces were added to both UCs.

A joggle was added at the upper end to stop the skin from being pulled in at the firewall.

The cowls were formed and mounted along with the lower firewall braces and the the lower engine baffle. The lower baffle and the firewall braces were put under the skin to create a cleaner look around the engine compartment. The oil cooler baffle has been formed but will go in after the engine is fitted.

Engine compartment

2007-09-25T13:26:00.000-04:00

Build hours: 210

Completed engine compartment on UCA to same point as UCB. Planned engine cowl and baffling arrangement since we are departing from the plans a bit in this area.

Engine compartment

2007-09-24T09:36:00.000-04:00

Build hours: 206

The filler pieces and skins for UCB were drilled and clecoed to the engine mounts. The skins were cut to their final dimensions and the double row of rivets and rivet pattern on the A to B skin was laid out. The skins for UCA were also hung for fitting to the engine mount.

A test was made on the front engine cowl to create a more finished look and appears to be workable. A 3/16" flange was added to the node cowl behind the spinner. This will cover the top of the slots in the attached flange and also give the engine cowl an edge to butt up against instead of being an overlap.

Engine compartment

2007-09-18T13:20:00.000-04:00

Build hours: 198

Jake, the shop rat, caught in the flash!

Anyhow, we riveted the top angle to bulkhead "A". Riveted the engine supports together and to the lower angle on "A" but did not rivet the lower angle to "A". We're planning to align, drill and rivet the engine skins before riveting the lower angle and supports to "A" so that blind rivets are not needed below the engine mount at the "A" bulkhead. This also means we have to order the nuts and bolts that become inaccessible after closure. Two additional changes are also being considered, see below. Installed the engine nutplates and mounted a plywood engine pattern to hold the mount square while fitting the skins.

Change 1 - Make the filler plates in two pieces. One piece rivets to the skin, the other rivets to the vertical engine support then the two pieces are riveted together when adding the engine ring.

Follow up: Decided to stick with the plan filler pieces and use blind rivets as needed.

Change 2 - Speaking of the engine ring... After looking at various examples of the engine ring implementation, we decided to purchase a real metal shrinker(Porto-Metal, I believe) and shrink the flange around the top of the ring. We needed the shrinker for the ribs anyhow to avoid fluting so why not!

Follow up: Fluting and hand skrinking aluminum in the T6 state is only practical for large radii and the metal shrinker must be used sparingly to avoid marking the material to much!

Engine compartment and tail components

2007-09-18T12:43:00.000-04:00

Build hours: 194

While waiting for some materials and our work schedule to synchronize, 10 hours was expended in cutting out blanks for the tail parts for both UCs. (horz. stabs, horz. stab forward spars, vertical stab forward spars, rudder spars and ribs) Additionally, the horizontal and vertical engine mounts were cut and flanged to the indicated angles and the "A" firewall angles were aligned and clecoed on.

When Rick and I got back together we were able to drill and cleco the engine mounts together and hang them on the firewall. The mounts were squared by clamping a wood spreader to the front and an engine compartment skin pattern was made. The engine mounts will be leveled when the skin is attached. Finally, all holes EXCEPT the firewall holes that hold the rudder bar attachment were drilled to 1/8".

We also gave metal shrinking a try on the filler plates for the front of the engine mounts. We flanged the straight edge of the filler plate in the brake and made a particle board form with a slot to accomodate the flange to tap the curved edge around. We bent the curved edge to leave 3 puckers. A wood block was clamped to each side of a pucker and the pucker was then flattened. The filler plate came out well but this method is not practical when a tight clamp cannot be applied to both sides of the pucker.

Shoudler strap doubler

2007-09-12T13:43:00.000-04:00

Build hours: 178

The shoulder strap attach brackets on top of the C bulkhead were added. The skin was trimmed to allow the plates to align with the bulkhead. The plate and doubler were given a mild radius to lay flat across the C to D skin seam since we attached the C to D skin in two pieces. We used driven rivets in this area - because we like to drive rivets. (If you choose to drive the rivets, be sure to wear hearing protection when you stick your head in the fuselage to buck the rivets:)) The doubler plate was attached with flush rivets so that any future bracket would not be hitting rivet heads.

UCB riveted

2007-09-08T21:38:00.000-04:00

Build hours: 174

Assembled and riveted UCB to the same point as UCA. Removed beam. The fuselages look great setting side by side!

UCB skin prep for riveting

2007-09-06T21:36:00.000-04:00

Build hours: 167

Clean and deburred bulkheads and skins.

UCB drilled

2007-09-05T21:31:00.000-04:00

Build hours: 165

Installed all skins on UCB and drilled up to 1/8". Removed all skins for cleaning and deburring. Moved bulkhead D supports to opposite side of bulkhead and removed beam beyond bulkhead D for easier removal later.

UCA riveted

2007-09-04T20:55:00.000-04:00

Build hours: 162

In a fit of progress, the remaining UCA skins were drilled up to 1/8" where possible, removed, deburred, clean and reinstalled. Rivets were installed and the beam was extracted leaving the following results:

UCA riveting

2007-09-03T22:04:00.000-04:00

Build hours: 157

Well, we finally get to complete assembly on some of these #!$ skins and bulkheads! Man, we've been doing this forever - isn't it done yet! Construction so far has always been hot, sometimes perplexing and once in a while just dang tiresome and frustrating. However, in the next few paragraphs, the plan comes together - who needs laser cut kits! Whoo-hoo!

The skeleton of UCA (refresher coarse for the slower readers - UCA = UltraCruiser "A") was further denuded as the last two skins, bulkheads and stringers were removed for riveting, deburring and trimming at the overlap. Additionally, the overlapping skin edge was inserted into the brake 1/8" and bent approx 3 degrees to create a tighter edge when riveted.

The skins had a lot of marking from skin oils and perspiration that was unattractive and could lead to surface corrosion on the 6061. Acetone or mineral spirits had no affect on the smudges. Some weak AlumiPrep (phosphoric acid etch normally followed by an Alodine treatment) on a sponge followed by generous rinsing was found to remove the smudges and return the aluminum to its originally bright state.

The E to F skin was wrapped and rejoined at the bottom stringer with clecoes and the top stringer was clecoed in place. E2 was riveted in followed by F and the stringers. The pieces were handled with cotton gloves during the riveting to avoid re-smudging the inside surfaces. Finally the three 1/4-28 nutplates were added at the appropriate E2 tabs.

Plan note:

F was not riveted where the tail wheel spring bracket will be and the top stringer was not riveted where the vertical stab lower rib will be added later.

Bulkhead E was put in place with a few clecoes and the stringers for the next section were riveted onto E. The D to E skin was rejoined on the bottom stringer and the top stringer was added. Bulkhead E was riveted in along with the stringers. Some denting or wrinkling as the rivets pull the skins to the bulkheads is inevitable at the change of angles on the skins.

Some more of the beam was removed (with joy!) and the D to F assembly was hung on the D bulkhead.

UCB was denuded so that we could get the original C skins back for UCA. C skins for UCB

(UCB = UltraCruiser "B" in case your still not catching on to the naming scheme) were cut from the originals. The original skins were repositioned on UCA ready to be drilled up to 1/8" holes.

At this point, there really should be a picture but I'm too pooped to walk back out to the shop!

UBC skin A to B doubler, vertical stab

2007-09-01T09:40:00.000-04:00

Build hours: 150

Drilled the A to B skin at bulkhead A and added the A to B skin doubler.

Notched the F bulkhead for the vertical stab and added the vertical stab as detailed on UCA. An ATS rivet gun was purchased from Aircraft Spruce for 97$. This rivet gun worked really well and made the riveting process enjoyable. It was well worth the expenditure. Even without prior experience, Rick was driving first class rivets on the first attempt. Well, I still hold the title of "Rosy (the Riveter)" for now.

UCB skins, A to B

2007-08-29T21:31:00.000-04:00

Build hours: 144

Drill and clecoed the previously fitted B to C skin. Moved the UCB fuselage into the saddle. Cut and fit the A to B skin continously checking the siderails for alignment. Drilled the siderails and clecoed up to bulkhead B.

UCB skinning, new B to C skin

2007-08-28T21:48:00.000-04:00

Build hours: 136

A new B to C skin was cut, fitted and ready for drilling. The siderails were aligned and leveled with the F bulkhead horizontal stab tabs up to bulkhead A. Looking forward to two skinned Cruisers in formation!

UCB skinning

2007-08-27T21:38:00.000-04:00

Build hours: 134

The first 3 skins sections were removed from UCA (sad moment) to be tested as patterns on UCB. The C to D section skins were tight but created an acceptable fit on UCB. After struggling with the B to C skin in an attempt to obtain proper alignment, it was decided to make a new skin using the exisiting skin as a starting point. There will be no pictures of this since this was not a particularly high point in the building process!

Vertical stab

2007-08-25T21:17:00.000-04:00

Build hours: 129

Parts to complete the vertical stab were completed in an earlier post. The E to F skin was notched to accept the vertical stab and the stab was carefully plumbed to the leveled fuselage. The 1" spacing holes were drill in the F bulkhead and the bulkhead was removed. On the bench, the doublers were drilled and clecoed leaving space for the rudder control hinge. This was a good warmup for all of the riveting to come as we calculated rivet lengths, finished head sizes and practiced on a few scraps. After botching about every other rivet on the test pieces, we became adept at rivet removal and boldly moved on to the vertical stab.

The doublers were riveted where possible on the vertical stab and bulkhead. The rudder hinges were then positioned on the stab, underdrilled and reamed to 3/16" for the An3 attachment bolts. The doublers were riveted on and nutplates were installed with 3/32 flush rivets. Again, stopped and admired...

A to B skinning

2007-08-24T21:07:00.000-04:00

Build hours: 123
Cut the A to B skin from the pattern and used the ratchet strap to pull it tight while drilling. Trimmed and installed the A to B skin and add the doubler at the A bulkhead. Also, trimmed the siderails square to extend past the A bulkhead by 1". Stopped and admired... Stopped and admired... Stopped and admired...

And the skinning still continues...

2007-08-22T21:43:00.000-04:00

Build hours: 117

This shows both sides of C to D installed, the C bulkhead bracing removed, and the B to C skin in place. Notice the level. Siderail levelness was checked many times to make sure that no twist in the airframe was being introduced.

C to D skin:

The C to D skin is easier to work in 2 halves. On the large skin, a slight adjustment on one edge can make a big difference in alignment on the other edges.

Plan Note:

The C bulkhead edge has to be notched to allow for the change of angle going forward. The plans do not indicate the number, placement or depth of notches. After looking at the factory skin picture, it appeared to be notched at the bulkhead tabs and again in the center of each tab. The notches need to be 1/2" to 7/16" deep. To shallow and the B to C skin will gap, to deep and the notch bottom will not be covered by the B to C skin.

B To C skin:

Three braces across the beam were used so that ratchet straps could be used to pull up the B to C skin. This allowed the skin to be positioned while remaining tight against the bulkheads, making sure the notches were covered. The joint on the C bulkhead does not lay as tight as the other overlaps so far but is acceptable. (There are several areas on the UC that only another builder would be able to appreciate the workmanship and this is one of them!) Wood strips and spring clamps were used to make sure the compound curve that occurs in the skin on the siderail was not getting out of hand which would cause ripples.

Finally, a saddle was made from the B and D bulkhead for fuselage support as the A to B skin pattern is prepared.

The skinning continues...

2007-08-12T21:30:00.000-04:00

Build hours: 110

The 3/32" clecoes were changed out for 1/8" clecoes and the tail was placed in a saddle so that skinning could continue. Bulkhead "C" was braced so that the edges would remain aligned during the pattern making and skinning process. The poster board pattern was fitted and trimmed for 1/2 of the C-D skin from the bottom stringer to the top stringer. The pattern was found to align correctly on the opposite half and also on both sides of UCB - we must have done something right! The C-D skin will be installed as 2 seperate pieces to reduce waste and make it easier to install. The additional seam will be covered by the turtle deck.

Pictures to follow...

UCB Skins

2007-08-11T21:30:00.000-04:00

Build hours: 105

Skins E-F and D-E along with the E2 bulkhead were completed on UCB. Both skins from UCA were used as templates for UCB.

E2 Installation

2007-08-09T10:21:00.000-04:00

Build hours: 97

After the E-D skin had been fitted and the E-F skin had been fitted and trimmed to the F bulkhead, the E-F skin was removed and a line was drawn 7 11/32" in from the F bulkhead edge. The beam was cut behind E and turned over. Bulkhead E2 was predrilled and then each tab was backdrilled after aligning the line in the tab hole. Tabs on alternate sides of the bulkhead were done until about 3/4's of the tabs were done. Then, one side was left open while the remaining tabs were completed to the center of the bulkhead.

Skin E-F

2007-08-05T10:02:00.000-04:00

Build hours: 91

Skin E-F was layed out and cut from the pattern. The .016 6061 is not very impressive while cutting and I was beginning to wonder if it was really better than the poster board. Anyhow, the wimpy skin was centered and clecoed to the top stringer and pulled together with strapping tape at three locations along the length. The holes were layed out to be centered on the front and rear flanges, drilled 3/32" and clecoed on the top fuselage half. The beam and fuselage was flipped and the skin was drilled and clecoed on the lower half. The .016 skin becomes amazingly stiff when wrapped and should be more resistant to weather than the poster board:)

Shop note:

The shop was 97 degrees and 60 percent humidity. Even with all the fans going and the excitement(?) of the first skin wrap, that temperature and humidity is a drag.Its obvious that the builder was suffering from too much heat (or.. if I only had a heart - The Tins Man's request from the Wizard of Oz)

Plan note:

You will screw yourself if you don't think far enough ahead since the plans nor the kit construction manual lays out a specific order or indicates why what your doing now will be IMPORTANT in the FUTURE! So... For the horizontal stab to be horizontal, the tabs on bulkhead F should be level. Its easy to lose a 1/16" while cutting and trimming the bulkhead. Add a lines width during alignment to the beam and the tabs will not be level when it time to add horz. stab doublers! To be continued and corrected...

Rudder Hinges

2007-08-04T09:47:00.000-04:00

Build hours: 86

The vertical stab and rudder hinges were made from 6061 1/8 square that was available. The hinge length was cut from the square stock and then multiple hinges were cut. After lay out the pilot holes were drilled, the angles were cut and a belt sander was used to finish and round piece.

Vertical Stab,Skin Patterns

2007-08-03T21:33:00.000-04:00

Build Hours: 82

The vertical stab blank was cut from .020 6061. The vertical flanges were made in the bending brake and 3" flanging pliers were used to bend the top tab. The vertical stab doublers were cut from 6061 .025 and formed in the brake. The vertical stab hinge doublers were cut and match drilled. This was completed for both UCs.

Plan Note:
The length for the vertical stab does not include the 5/8" tab. The plans could use more detail around the vertical stab. The information is all there but it requires coalescing information from 3 different drawings.

Patterns were made for skin E-F and D-E. The long edge of a sheet of poster board was taped to the lower stringer with 4 1" strips of masking tape and wrapped over the top stringer. Another piece was overlapped on the lower stringer 3/4" taped and again, wrapped over the top stringer. The top overlap was taped with a 2" wide strip of masking tape. The flange edges were marked on the inside of the poster board. The poster board was then removed and trimmed to shape.

Stringers

2007-08-02T09:24:00.000-04:00

Build hours: 76
The stringers for both planes were cut from the end of a sheet of .020 6061 with the Malco snips. Even though a shear would be nice, the big Malco snips make nice clean cuts with relative ease. The layout was done for the flange lines and relief holes were drilled at the corner of the tabs. The blank was loaded into the brake. Bend, flip, and bend again. Duckbill pliers was used to bend the end tabs. A small amount of length adjustment can be made by changing the tab bend. Two holes were drilled on the center line of each bulkhead, top and bottom, at 1/4" and 3/4" from the flange. Each stringer was then centered on the bulkhead and aligned with a wood block to be flush with the flange or tight inside of the flange, drilled and clecoed.

Plan Note:
The plans show a parts layout on the aluminum sheets. I would guess this is the layout used for laser cutting the parts. It is not always practical to follow these layouts if you are scratch building, i.e. - the stringers are made from .020 and are wedged in all around the a-b, and b-c skins that require patterns to be made at a later time. The stringers were cut from the end of the .020 sheet as required.

Siderails

2007-07-28T21:09:00.000-04:00

Build hours: 70

The horizontal stab inboard and outboard doublers were cut from .040 6061. The doublers were drilled with 3/32" pilot holes for rivets and the 1/4" stab bolts. The doublers were then formed on a 3" PVC pipe to conform to the bulkhead F radius.

The first siderail was time consuming because the plywood had to be trimmed multiple times to arrive at the correct radius. (see note) The bending process goes quickly and took every large clamp available. It seems you can never have to many clamps.

Plan note:

The plans indicate a 104" radius for the siderail plywood form. A 52" radius (half of the 104" indicated?) was used to get the desired bend after springback. Well... the plans said the plywood may need to be trimmed:)

The blank angle was loaded and the arc center of the siderail and the form was aligned.

Multiple clamps were used to keep the angle from twisting and raising the form.

Note the amount of springback after the siderail is bent and released.

An for the final results.

Bulkheads complete on UC 2

2007-07-27T21:03:00.000-04:00

Build hours: 62

The second set of bulkheads have been hung with bulkhead C taking the most time to align. The pushrods guides were added but the tabs still need to be adjusted. Here are the 2 Ultracruisers in there first formation shot.

More bulkheads on beam

2007-07-25T10:43:00.000-04:00

Build hours: 58

Bulkhead C,B and A were added to the beam as described previously and alignment was rechecked on all bulkheads. With the addition of the stringers and siderails, the bulkheads will be ready for skinning - time for another materials order.

The beam for the second fuselage was swapped onto the taller set of sawhorses. The beam center lines and bulkhead positions were marked, bulkhead supports were added and F was attached to the beam end.

Bulkheads on beam

2007-07-23T09:15:00.000-04:00

Build hours: 54

Center lines were snapped on the beam with a chalkline and plugs of 2x4 were cut and installed in each end of the beam. Bulkhead "F" was attached to the end of the beam with a 1/4" lag screw and secured from rotation with 2 additional wood screws. The bulkhead positions were measured and marked all the way around the beam and the bulkhead supports were attached checking for square, plumb, perpendicular etc!

The bulkheads were then secured in position with C clamps. Sounds simple but a lot of effort went into the alignment of the bulkheads with double checks on all measurements.

Lastly, an alignment tool was made from some scrap Al tube and PVC for positioning of the pushrod guides for installation. The guides have been drilled and clecoed in place.

Beam

2007-07-20T21:12:00.000-04:00

Build hours: 44

The beam was built from 16' #2 yellow pine 1x4s. The leftover 4' will be ripped to make 1x2s for mounting of the bulkheads.

Bulkheads near completion

2007-07-19T08:53:00.000-04:00

Build hours: 41

All of the corner tabs are in and the control pushrod guides are cut. Final positioning and installation of the pushrod guides will be done after the bulkheads are on the beam and the hole alignment is confirmed. Vertical center lines and horizontal positioning lines need to added to the bulkheads with a final inspection before going to the beam.
Also, the hand riveter head fits the air riveter which will make the next 3900 rivets a lot easier to pull!

Riveter head mod

2007-07-15T21:15:00.000-04:00

Plan Note:

The riveter head required modification per the plans to create a domed head out of a flush head rivet. The plans suggest the tip needs to be annealed to be drilled but the tip on the Harbor Freight Hand Riveter drilled without being annealed. The initial attempt with a 1/4", 135 degree drill bit was too deep and created more of a dome than we deemed desireable. Some of the tip (.015?) was remove and a 5/16" bit was used to shallow out the depression. This change created a flatter rivet head.

Bulkhead E2, F and corners

2007-07-15T21:00:00.000-04:00

Build hours: 37
Bulkhead E2 was cut from .025 2024T3. The bulkhead was cut, trimmed and filed as before. A 1 1/2" hole saw was then used to cut the lightening holes. The tabs were bent forward and the lightening holes were flanged rearward with a flanging die made from particle board. The flanging process created a bow in the bulkhead which should come out when installed otherwise the bulkhead will have to be remade.
Bulkhead corner tabs were made for bulkhead E and installed. Both bulkheads had some oilcanning after all the flanging so before installing the tabs, the bulkhead was C clamped back to the original form. One E bulkhead was completely drilled and clecoed before riveting and the oilcanning remained. The other was drilled, clecoed and riveted one corner at a time an exhibited almost no oilcanning. The 040 for bulkhead F was rough cut and the rudder and elevator holes were cut with a 2" hole saw. Scrap one piece of .040 when I pulled out the 2 1/8" hole saw! The .040 was tough to cut even with the 14" Andy Snips, luckily there is not a lot of .040 or thicker components!

Bulkheads B-E

2007-07-14T20:14:00.000-04:00

Build hours: 31

Bulkheads B through E and a second set of A-E were completed in the same manner as bulkhead "A". Tabs on curved areas of the bulkheads will not lay flat when bending. This was disconcerting at first but most of the tabs will be at some angle less than 90 degrees to match the skin. Tabs needing to be at 90 degrees or more will need fluting or shrinking. Next is to had the bulkhead corner tabs and control guides before moving to the beam.

Plan Note:

In preparation for cutting out E2 it was noticed that the bulkhead template specifies .016 material but the layout on Sheet 0 shows the bulkhead on the .025 sheet. A quick email response from Hummel indicated the bulkhead could be .016 to .025 - builders choice. We chose .016 2024T3 because of the strength and weight savings.

Bulkhead "A"

2007-07-11T14:50:00.000-04:00

Build hours: 17
Up the learning curve we go! It took 3 hours to turn out the first bulkhead. Hopefully the experience will allow the next 13 bulkheads to go quite a bit faster.
The bulkhead "A" template was outlined with a Sharpie Ultra Fine Point onto the .025 6061T6. The template was then rough cut with an air nibbler and then trimmed with tin snips. A metal hole punch was tried to punch a clean hole at the bottom of the bulkhead notches but the punch body obsured the hole outline. In the end, the hole was drilled with a 3/16" bit and deburred just as quickly. The notches were clipped and the entire outer edge of the bulkhead was smoothed with a fine metal file.
The blank was then bolted and clamped between the 2 forms. A dead blow hammer was used to tap the tabs over. After the bulkhead was removed from the form, the tabs were adjusted with pliers. The final step was to admire the completed bulkhead!
The pictures represent the steps taken but are not bulkhead "A" or the same bulkhead.

Bulkhead forms

2007-07-11T14:29:00.000-04:00

Build hours: 14

The patterns were outlined onto a piece of 5/8" particle board. A combination of bandsaw and jigsaw was used to cut the line on the particle board. Two forms were made for each bulkhead. The form were aligned with two 1/4" bolts and smoothed on a disc sander. The forms were then labeled and marked as TOP and BOTTOM and which way to bend the tabs to avoid a screwup later when metal was involved! Finally the bending edge was radiused with a coarse file, sanded and checked with a radius gage. A final check was made to verify the bulkheads matched the original plans outline.

Bulkhead templates prepared

2007-06-22T21:16:00.001-04:00

Build hours: 4

So it has been a few days since the last post. No, we haven't given up already! The bulkhead templates have been copied, cut and pasted to poster board to create a firm template. It was a real treat to create individual bulkheads out of the plans which have all the bulkhead outlines intertwined on 2 pages. In the hopes to document each step I will attach some pictures.

Also, after debating to buy or build some type of bending brake with shop space at a premium and budget to consider, I took a shot at building one. The 48" brake was built from red oak 1x4s, a piano hinge and a piece of steel angle from Lowes for approx. 40$. The brake bent a 45" piece of 2024-T3 .016 with no problem. The brake appears to be suited for the task.

Coming soon - bulkhead forming...

Tools Used

2007-06-09T12:31:00.001-04:00

Tool List Updated 8/29/2007

Hand Tools:

14" Andy Snips (Malco MC14N - this size is really needed on the .040 matl)

10" Tin Snips (Wiss)

10" Fine File

Countersink - small hole deburring and rivet countersinking

(100 degree required for AN countersunk rivets)

( 120 degree for Cherry-Lok countersunk blind rivets)

Deburring Tool - large hole deburring

Homemade 48" Leaf Brake

http://cwsnyder2001.blogspot.com/2007_06_01_archive.html

Homemade 17" Heavy Duty Leaf Brake

http://cwsnyder2001.blogspot.com/2008_08_01_archive.html

Dead Blow Hammers (Harbor Freight)

Cleco Pliers

Power Tools:

Drill Press

Dewalt 12V Drill

Band Saw - cut out bulkhead forms, could have used jigsaw

JigSaw - cut out bulkhead forms

Belt Sander - cleanup bulkhead forms

Air Tools:

Air Nibbler - rough cut inside bulkhead patterns

Air Riveter for blind rivets - Harbor Freight

Air Drill - good for tight spaces

Air Angle Drill - good for tighter spaces

Air Hammer - can be used for riveting on the cheap

(A model with 3000 bpm or less should be used)

Rivet Gun - ATS 2x from Aircraft Spruce

(because I want to be a REAL airplane builder:))

Misc:

1/8", 3/16", 1/4" drill bits

Unibit/Step Drill

1 1/4" hole saw

1 1/2" hole saw
6" Vise

2" C Clamps - 16+

4" C Clamps - 4+

Batting gloves

Compass

Sharpie Ultra Fine Pens

(Red shows up the best, also, it doesn't look like a shadow when viewed through a hole)

6" Machinist Rule

Bucking bar from A&P school days

3/32" Clecoes - 300 (Aircraft Spruce)

1/8" Clecoes - 200 (Aircraft Spruce)

The blog begins...

2007-06-08T13:52:00.000-04:00

Build hours: 0

A friend and I have decided to build two Hummel Ultracruiser ultralights. The plans have been purchased and reviewed. The shop is being updated and cleaned and materials for the bulkheads has been purchased. Hopefully, pictures of the build progress will follow shortly! In the meantime, I have posted a few pics of the Ultracruiser (UC) and prior projects.

Hummel UltraCruiser Prototype

Kolb Firestar I (current ride)

Titan Tornado I (prior project)

Pegasus Quantum 503 (last trike)