May 27, 2022     Gear door link - (2 hours) Category: Landing Gear

Spent quite a bit of time doing some trial and error to determine the right length for link and the location for a pivot point to connect the gear door to the landing gear. This is a continuation of the work I was doing on the gear on May 22nd. I think I finally found the right pivot location and the corresponding length of link.

  May 25, 2022     Wheel well skin doublers - (1.5 hours)       Category: Landing Gear

Made some doublers for the skin at the edge of the wheel well cut outs. Epoxied doublers and support pieces into place.

  May 22, 2022     Gear door and gear clearance - (3 hours)       Category: Landing Gear

I spent some time over the last couple of days fitting the gear door and ensuring clearance for the tire, wheel, and brake assembly when fully retracted.

There are no drawings for the links that connect the gear door to the landing gear. With the exception of a couple of bent and broken pieces, there is nothing left over from the original gear door supports. From photos and what I can gather from the broken pieces, it appears that the gear door is connected to the lower leg of the gear through some rods that pivot on the door itself. Because the gear door hinge is about 4 or 5 inches from the gear pivot itself, the door travel doesn't match the gear leg travel, but travels parallel to the gear leg, exposing more of the wheel as the gear is retracted. This requires a link that is the correct length to pull the gear door in fully when the gear is retracted, but also provide sufficient clearance for the wheel when the gear is extended. The location of the pivot point on the gear door is also critical to this to operate properly. Lastly, since the rods are connected to the lower, unsprung, section of the gear leg and the door hinge is on the wing which can move relative to the lower leg as the gear compresses, the door will draw closer to the wheel when the gear leg compresses.

I had to trim down the upper skin stiffener in the wheel bay. The new wheel and tire combination being wider than the original means that the original dimensions of the structure didn't provide sufficient clearance.

  May 09, 2022     Skins around wheel bay - (3 hours)       Category: Landing Gear

Made some adjustments to door hinge.

Fitted skins for wheel bay area. A lot of trial and error to get the correct fit around the wheel without the cutout becoming excessively large. Some doublers will need to be installed and some further trimming around the tire.

  May 04, 2022     Gear door hinge - (2 hours)       Category: Landing Gear

Spent some time resurrecting the bolts and nut plate from the original gear door. The original hinge was destroyed and its matching partner was long gone.

Built up a spacer as per original, and duplicated the bolt spacing as per the original. Ready for install.

Did some more sanding in prep for leading edge installation.

  May 01, 2022     Gear Door Layout - (2 hours)       Category: Landing Gear

Established size and shape of gear door based on position of ribs, gear, and skin.
Lots of thinking, a bit of taping, some measuring, some marking, and finally, some cutting.

Of course, I cut the door based on the wrong marks. Measure twice, cut once right? It doesn't help if you cut to the wrong marks.

So, I got an extra, albeit smaller door if I ever want to build a 90% scale version of the Dalotel. Cut out a second door to fit properly.

  Apr 22, 2022     Assembled Landing Gear into wing - (2.5 hours)       Category: Landing Gear

With the wing inverted for the final skinning, I was able to install the landing gear. I installed the gear leg, the retract arm and link, the lower fork, the brake and axle and finally the wheel. This is the first time everything's been together. I will take it apart a couple of times before I'm done.

The gear is another area where Dalotel and St. Poulet et Fils did a fantastic job on the build. The lower bushings for the leg are held in place by four set screws that were custom machined just for this purpose. Once fully installed, a wire ring wraps around the gear leg in a machined slot that lines up with the screw slots. Very clean.

Assembling it will allow me to raise and lower the gear to determine the skin cutout for the gear and gear door.

  Mar 28, 2022     Machined Pin - (1 hour)       Category: Landing Gear

Refer to Jan 14, 2020 for the first pin to crank assembly.

Recently I had a second pin machined for the second landing gear crank. I was able to use natural cooling to reduce the size of the pin back in 2020. I hadn't gotten around to getting the second pin machined until recently and it's not so cold outside. Last week I tried fitting the pin in place by only heating the crank with the pin chilled to the outside temp of around 0 degrees C. The pin dropped in about a 1/16" before it got stuck. I was able to use a punch and drive it out. It certainly confirmed that I'd need to chill the pin to get it to fit in.

So today I got a few pounds of dry ice and got the pin nice and cold (and small).
I also heated the crank with the propane torch. Between heating the crank with the hole and cooling the pin, the temperature difference was ideal for the pin to drop right in.
Just for giggles I got an infrared thermometer to measure the temperatures. I got the crank close to 200 degrees C. The lowest temp the thermometer would read was -40 degrees C. Because of the dry ice, the pin was obviously much colder than that.

  Mar 05, 2022     Machine work - (2 hours)       Category: Landing Gear

Had the landing gear link machined down to 10 mm thick to match original. Had the end holes bored out to fit bearings. Heated the ends of the link and fit the bearings into the holes before the ends cooled. Used a punch to dimple the link, preventing the bearings from coming out.
Had a new link pin machined. It didn't turn out as good as it should so it's going to be redone. No pics.
Also had the bent landing gear torque tube straightened so that it can be reused. It now slides in and out through the splined section. The cut off end will have to be rewelded.

  Feb 28, 2022     Landing gear link - (1 hour)       Category: Landing Gear

I needed to feel like I was making some progress so I took a break from the electrical work.

Back in June 2020 I had the missing retract link cut out on a waterjet table. This worked out beautifully but it did leave the edges a little rough. I spent some time cleaning those edges up. The link is thicker than the original. I may get it machined down to match the original thickness when I get the bearing sockets machined out. Or maybe not. Once I get that done, I'll clean up the edges of the lightening holes too.

  Dec 01, 2021     Retract Motor Assembly and Install - (3.5 hours)       Category: Landing Gear

Reassembled and installed retract motor. Took longer than it should have but isn't that the case with all projects? It was a challenge to reinstall due to the lack of clearances and such. This required the heavy motor, the manual retract crank assembly, the outboard bearing set, the supporting frame assembly, and all the associated bolts to come together all at the same time. The plane wasn't designed for serviceability.

There is a hand crank that engages to the motor to manually crank the gear up. This crank assembly slides on a rod that is mounted under the floorboards and engages and disengages from the output shaft of the retract motor. The cranks are mounted right in front of base of the rear control stick. It will be very awkward for the pilot if they need to use the manual crank.

It takes 10 full revolutions of the hand crank to get one full revolution of the retract motor output shafts. These shafts feed the torque tubes that are the input to the retract gearboxes in the wing. The input to the wing gearboxes require 37 revolutions for one full cycle of the landing gear. My math tells me that it will take 10 x 37 = 370 revolutions of the hand crank to cycle the gear one full cycle. Assuming extending the gear from retracted to full extension is exactly half that, it's a measly 185 revolutions of the hand cranks to lower the gear in the event of a failure of the retract motor. Let's hope that's never happens.

  Oct 18, 2021     Retract motor and gearbox disassembly - (2.5 hours)       Category: Landing Gear

Pulled the retract motor apart. Found the gearbox at the end of it full of 50 year old grease. Although it wasn't dried out, it wasn't exactly fresh. Took an awfully long time to scoop, scrape, and force the grease out. It was tough to get out from underneath the central gear and shaft. I put it in a varsol bath to get the last of the grease out. Unfortunately the varsol also removed the 1960's era hammered finished paint. Check out the beautifully machined gears and casting for the gearbox though. This motor and gearbox assembly is one-off so I have to get the retract motor working properly. Once the gearbox was fully cleaned, I filled it back up with fresh grease and reassembled.

  May 25, 2021     Cleaned up manual retract assembly - (1 hour)       Category: Landing Gear

Disassembled and cleaned up the manual retract assembly. Re-lubed and reassembled.

  Jan 20, 2021     Painting - (1 hour)       Category: Landing Gear

Painted the forks and the re-welded gear leg. Unfortunately one gear leg was scratched a little bit when the fork was welded up. You can see the scratches in the photo of the assembled gear. Dennis buffed out the scratches as best he could but they still show. They look worse in the photo than real. As ugly as they are, they won't impact operation of the gear. The gear is suspended by a stack of rubber blocks so the seal between the upper and lower gear legs isn't critical.

  Jan 17, 2021     Gear leg update - (1 hour)       Category: Landing Gear

Just got my gear legs back from the welder. They look great. Dennis had the pieces for many months but this wasn't a problem. He was working on my gearlegs between his other, bigger projects. Since I don't need the legs for a while yet, I wasn't worried. It was exciting to get them back though and see how they looked and fit together. I test fit the axle and brake assembly on one of the legs. It all fit as planned. Thanks to the 3D design and water jet table work that Grant at Excalibur did to cut out the pieces, they all fit for Dennis. Dennis did a beautiful job welding it all together and keeping the fork straight and true. Additionally, Grant matched the welding pattern to the welding that was done on the gearlegs 50 years ago. It all looks like it was done by the same person. Very nice touch. Thanks Grant.

Lastly, Grant repaired the upper gear leg where it had cracked below the pivot. This crack was easily identified when I did the dye-penetrant test on the pieces. See January 30 / 2020 entry for picture.

  Dec 02, 2020     Landing Gear Welding       Category: Landing Gear

I haven't worked on the project for the past month or so as I've had some other projects to attend to. However, I have had the gear legs and forks at my favourite welder. Dennis Brown of Dennis Brown welding has accepted the challenge of welding up the new forks and repairing the damaged gear. As a reminder, the fork on each leg was damaged beyond repair in the accident 40 years ago. I cut them off and re-engineered some new forks that would work with the new wheel assemblies. The original wheels were a one-off design that fit an obscure tire size that's no longer available. Only one of the original wheels survived the accident and the subsequent 40 years of storage and movement. It was a custom machined magnesium wheel to fit the oddball tire size. Not only that, but the original plane had drum brakes from a Citroen. This is understandable since the plane was designed and built in France over 50 years ago... So, the new forks were designed to fit a Matco axle, wheel and brake assembly with a fairly conventional tire size. The new tire is almost the same outer diameter as the original and it still fits into the wheel bay when retracted.

Dennis has done some preliminary welding, tacking the pieces we'd cut out on the waterjet table a few months ago.

  Jun 19, 2020     Cut out plates for landing gear - (3 hours)       Category: Landing Gear

Ok, so I didn't really do much today other than provide some clarity to the design and drawings (including my modifications required to mount the new wheels and brakes.) But it took about 3 hours of attention to provide that guidance and to watch the cutting out of these plates.

The first one to be cut was the retract link. One of the original links was destroyed or lost in the accident. The second one is still in great condition and will be used for the plane but a second one needed to be cut. The original link was 10 mm thick. Ray, the original restorer couldn't get 10 mm 4130 when he sourced the metal so he got 1/2" thick instead. 1/2" or 12.5 mm is slightly thicker and slightly heavier but it's not an issue at all for this purpose. We had enough material to cut out two links (one for a spare) and rough cut the holes for the bearings. I'll take the links to a machinist to have the holes cleaned up so that the bearings can be pressed in.

We also cut out the pieces to make the two landing gear forks. I took the original Dalotel design and modified it to fit the Matco axle, wheels, and brakes that I'll be using. The original forks were not only damaged beyond repair in the accident but they had an axle welded to them. The axle fit the custom, one-off magnesium wheels that Dalotel made for the plane. Like the retract link mentioned above, one of the wheels has long since disappeared. The forks are made from 0.080" or 2 mm thick 4130 welded into a box section. It will be exciting to see them fully welded up.

  May 08, 2020     RH gear work - (2 hours)       Category: Landing Gear

Hung RH landing gear and spent some time cleaning the bushing that the gear retracts on. It had a little bit of surface corrosion and with a bit of work with a scotchbrite pad and then some polishing compound, aka toothpaste, got the gear to rotate much more smoothly. Did the same on the landing gear retract gearing. Of course, cleaned up and greased the bushing for use.

  Apr 11, 2020     Cleaned up RH landing gear retract assembly - (1 hour)       Category: Landing Gear

Cleaned off old grease and dirt from RH landing gear retract gearbox. Even found some of the barley or wheat or whatever the crop was that the plane was put down in on its last flight.

Reassembled retract gearbox including mounting old electrical switches. These switches will be replaced with new ones when the time comes but the old ones were mounted to show how they go.

  Feb 11, 2020     Removed damaged fork - (2 hours)       Category: Landing Gear

Had fun making sparks, grinding the welds that held the original forks to the landing gear legs. Need to prep the legs for the new forks.

Started with the angle grinder to remove the large sections, then used the grinding wheel to smooth things out a bit, finished with a file and some sand paper.

  Feb 08, 2020     Landing Gear Fork Design - (1 hour)       Category: Landing Gear

After Grant and I drew out the spar plate drill guide, we spent some time on the computer designing the gear leg fork. The fork is a slight modification to the original design from Dalotel. We had to make some changes to allow for the slightly wider but smaller diameter wheel and tire. Additionally, the new axle and brake assembly are bolted onto the fork rather than welded on. These and a few other changes will result in a stronger but easier to construct fork.

Attached are some images of our design so far. There are going to be some minor changes and I'm going to review the design with my welder to see if he has any suggestions to simplify manufacturing for him. All in all a great day of progress. I'm most grateful to Grant for the time he spent with me working on this design and the drill guides that he'd cut out. Absolutely beautiful.

  Feb 01, 2020     Tie-downs - (2 hours)       Category: Landing Gear

Tested the squat switch again. Was hoping that the spray electrical cleaner from yesterday would have worked it's way into the contacts and gotten the switches working again. No such luck. It looks like I'm going to have to rely on a single gear squat switch and maybe a shield to prevent inadvertently hitting the retract switch while on the ground.

One thing that's missing from this plane is/are tie-down points. I've been looking at various spots to mount them. I considered different areas within the wheel well but those locations would either be in the way for the retraction gear or the tie-down rope could potentially drag on the linkages or the gear door. I could have chosen a location outboard of the wheel wells, secured to the spar somehow, but I didn't want to mess with the spar. I'd rather use hard points already part of the spar assembly. I've decided to secure some brackets to the backside of the spar using the bolts that hold the landing gear mounting plate to the spar. If that area is strong enough for the landing gear, then it's also strong enough for a tie down point.

I fabricated the pieces from some steel angle. A few minutes drilling holes, a few minutes making sparks with the angle grinder, and then a bit of clean up with some more delicate tools resulted in a decent pair of brackets. Further cleanup and then a coating of primer and they're ready for install.

  Jan 31, 2020     Squat switch testing and gear door connections - (1.5 hours)       Category: Landing Gear

Did some further testing on the squat switches. Used a long piece of music wire to reach into the landing gear and touch the electrical connections on each of the switches. This allowed me to test the continuity of the wiring for each gear leg. The good news is that the wiring is intact. The bad news is that it proves that the switches are faulty. After more attempts and inspection, I'm still at a loss on how to remove them and replace them. I don't think switch accessibility and maintenance was considered during the design of the gear. I put a long straw in the nozzle of some switch contact cleaner and gave the switches a generous spraying. My hopes was that cleaned the contact points and got the switches working. So far, no luck. Worst case scenario; I only rely on the working squat switch in the LH gear. I could install a cover on the retraction switch that's on the panel. That could help prevent inadvertently retracting the gear when the plane is on the ground.

Had a look at the links that connected the landing gear doors to the gear itself. Only 3 of the 4 links "survived" to make it to me. One of the 3 was badly bent and when I attempted to straighten it, it cracked. It actually made it to within about 1/4" of being straight before it cracked. I was surprised that it made it that far. Each of the links were made like turnbuckles with opposites threads on opposite ends. There are some beautifully machined fittings on either end that threaded into each end allowing one to rotate the link to shorten or lengthen the connection without having to disconnect it from the gear door. Unfortunately only one of the fittings survived undamaged. So I'll have to make something to replace them.

  Jan 30, 2020     Inspection and measurement - (2 hours)       Category: Landing Gear

Used the dye penetrant to check the RH gear legs for any more cracks beyond what I could see with my naked eye. Fortunately no more cracks. See attached picture of the crack. I'll get that fixed up when the fork is welded on. Once the gear leg was all cleaned up I took measurements of everything to make the necessary design changes to get the ideal fit for the new wheel/tire combo.

While I was in the cleaning mood, I cleaned up the retraction link and reassembled the entire upper leg and retract system. The link had 50 years of staining on it so a bit of time with some 600 grit sandpaper and elbow grease and it's nice and shiny. Not really important for the operation of the plane but it felt like the right thing to do. Gave it a coating of spray wax to seal it and protect it for another 50 years.

  Jan 29, 2020     Squat switch - (2 hours)       Category: Landing Gear

Today I finished cleaning up the RH landing gear and tried to figure out the wiring of the squat switch.

The squat switch is used to identify when the landing gear is supporting the weight of the plane. Most importantly, this switch provides the lockout logic so that one can't retract the landing gear when the plane is resting on the ground. That would be a bad day.

A simple switch is either open or closed requiring two wires. The existing wiring that's coming out of the gear legs is 4 wires. What do all these wires do? What is the logic? I figured this would be a simple and fun process to determine the switch operation and logic. I should mention that the switches are buried into the landing gear and I hadn't been able to figure out how to see them let alone access them. It goes without saying, that the switches are not shown in the drawings. Anywhere. And the drawings of the gear legs are at best vague, and in some cases, different from what was built.

By removing the central rod from the lower leg, I was able to manually feed it through the centre of the upper leg and I could hear it tripping a micro switch. This rod is about 1/8" diameter and is normally secured to the bottom of the lower slider. It slides up into the upper housing when the gear is compressed with the weight of the plane to trip the squat switch.

I stripped the insulation from the four wires and labelled them 1 through 4. The numbers really didn't matter, they are just to identify one wire from another. I tested the continuity between each wire with the rod out and with the rod in. In all cases the circuits were open. That is, it didn't make a difference whether the rod was in or not. Well that won't do. Doing the same thing on the LH gear I was able to determine that there were two pair of circuits. When the rod is inserted (weight on the landing gear) each pair of circuits are closed. When the rod is removed (weight off the landing gear), all circuits are open.

Unfortunately I'm not getting that output from the RH gear.

Going back to the RH gear, I could see that the central hole in the upper leg has threads in threads in the fitting. As luck would have it, the hole was an 8mm thread and I just happened to have some long 8mm bolts that were used to bolt the landing gear assembly to the spar. I drilled a 3/8" hole through the centre of a heavy steel plate and passed the bolt through it, threading it fully into the end of the fitting within the upper leg. Turning it over so that the weight of the plate was hanging on the bolt, I gave the gear leg a couple of vertical jolts. Success! The inertia of the heavy plate pulled the fitting from the gear leg. The fitting was just press fit into the inner cylinder.

With the fitting removed I could see that the squat switch is actually two microswitches. Hence the four wires coming out of the top of the gear legs. These switches are installed in an assembly that's mounted about 6 inches into the gear leg. I'm still not able to access them yet. I believe the inner cylinder is press fit onto a boss at the opposite end of the gear leg. At this point I don't know how to access them or how to remove the inner cylinder. I might have to sleep on it.

  Jan 28, 2020     New Wheels and Brakes - (3 hours)       Category: Landing Gear

My Matco wheels and brakes arrived today from AC Spruce. Yay! I took the angle grinder to the original fork to remove the brake mounting post and axle. I am just using the original fork to test fit the whole assembly and solve any fitment issues. Once I have determined the fitment, I'll design a new fork for the new wheels and brakes.

Since I was back to the landing gear, I decided to have a good look at the RH gear and start figuring out what needs to be done with it. I disassembled and started cleaning it. Discovered what appears to be a crack in the upper end of the outer housing. This isn't surprising as there was a lot of force applied to the gear when it last "touched down". I'll check the entire assembly with dye penetrant.

  Jan 14, 2020     Inserted landing gear crank pin - (1 hour)       Category: Landing Gear

Took advantage of the cold outside to chill and shrink the newly machined pin for the landing gear crank. This pin is designed to have an extremely tight fit in the landing retract crank. My machinist had used a 10 ton press to push the damaged pin out. Since I don't have anything as powerful as that I wanted to ensure that I had the greatest chance of success by using temperature difference. Since it's -32 C outside, there's a lot of temperature difference from when it was machined. I also heated up the aluminum crank arm that this pin fits into. I used a propane torch and gently heated it to get the maximum potential difference in temps between the two pieces. I prepared some wooden blocks to fit into my vise to protect these pieces and to provide room for the pin to protrude once it was pushed into place. I practised the motions and prepared everything for this critical activity as there would be no second chance. Wearing gloves I pulled the pin back in from the cold and brought it to the nice warm aluminum crank. It just dropped right in. There was no effort at all. I couldn't believe how much expansion there was on the warm aluminum and how much contraction there was on the cold steel. Within seconds the aluminum had contracted and the steel had expanded. The pin was as snug as a bug and it didn't require any effort with the vise. It would have been interesting to see if the pin would have dropped in if the aluminum hadn't been heated.

I then added the safety wire to the cap screws that connect the arm to the shaft and reinserted the assembly into the wing and reconnected the retract linkage.

  Jan 06, 2020     Picked up new pin from machining - (1 hour)       Category: Landing Gear

Picked up newly machined pin from machinist. This pin is part of the landing gear retraction linkage. I've had a wooden dowel in it's place for the time being so it will be nice to get this pin into place for complete assembly. I'll have to press the pin into the idler arm on the retraction system.

  Jan 05, 2020     New Torque tube and Universal Joint - (1.5 hours)       Category: Landing Gear

Compared new retract torque tube and splined section with original, undamaged torque tube. The new torque tube is the splined section and universal joint from a steering column. It will replace the torque tube that was bent in the accident. Test fit new tube and universal joint to confirm it will work.

Good news, it will. It will require a bit of machining to get the ends to match up and such but it's all doable. Certainly less work than trying to machine a brand new torque tube and splined section as per the original one.

  Jan 02, 2020     Remaining bolts arrived - (1 hour)       Category: Landing Gear

The AN5-60A bolts from AirCraft Spruce arrived earlier this week. Installed them in the landing gear mounting plates. This effectively ties the landing gear to the spar. Ideally, I should have ordered bolts about 1/4" shorter but these will work with a few extra washers.

  Dec 21, 2019     Retract indicator pin - (1 hour)       Category: Landing Gear

Took a break from sanding and gluing and decided to fabricate a new indicator pin. There are indicator pins at the top of each gear leg that extend upwards from the top surface of the wing when the gear is down. They retract flush with the wing surface when the gear is retracted. One of the indicator pins was damaged and unusable. To create this pin I took some 1/2" aluminum rod that I had laying around and turned it on the lathe bringing it to match the 8 mm (approx 5/16") diameter of the original rod. I machined an indicator grove in the rod just like the original and drilled a hole through it to secure it to the landing gear with a clevis pin. Even though it's only aluminum, drilling directly through a small diameter rod is a challenge with a simple drill press. The drill bit doesn't want to penetrate and wants to wander as you're starting the hole. A little bit of patience and careful application of pressure allowed me to get the drill to start properly. Thinking about it some more, I could have run a small diameter file across the edge of the rod to provide a shallow for the drill bit to start in making the process easier. Oh well, next time. To cut the slot in the indicator pin, I carefully used a hacksaw to make two parallel cuts and then widened the slot with a narrow file and some sandpaper. A little bit of red paint to match the original markings and voila. I was pretty pleased with the results considering it was all done by hand.

  Dec 16, 2019     Wheel fitting - (2 hours)       Category: Landing Gear

I took the grinder and cut away the buckled and damaged section of the landing gear fork. This allowed me to pull the remaining side of the fork back into approximately the correct position. I then reassembled the landing gear and mounted my tire on the axle to test fit.

I sourced a Goodyear 500 x 5 tire that seemed to have all the right specs. It was the largest diameter tire that I could find with the smallest width. Since the original tires are no longer available I'm having to find something that will fit. The originals are much larger in diameter and very narrow.

Have a look at the last photo. From left to right: A 5.00 - 5 from Aero Classic. Slightly larger diameter is a 5.00 - 5 from Goodyear. Even larger diameter again is a 380-150-5 from Aero Classic. Lastly is the original Dunlop 400 - 100 tire. The first three all fit on a standard 5" wheel. The original tire fit on an 8" wheel with drum brakes. The original wheels and brakes were all custom built for this plane. Only one wheel survived this long and the brakes aren't worth reusing. So even if the original tires were still available, it means new wheels and brakes.

I mounted the Goodyear 5.00 - 5 tire on my plywood "wheel" and mounted it onto the landing gear axle. It will fit easily. I then mounted the 380-150-5 on my plywood "wheel" and tested it for fit. It looks like it might work. It will give me the largest diameter possible and although it's fairly wide, it might just fit into the wheel wells without protruding below the lower wing skin. Since I'm getting new forks built, I'll design them to provide clearance for the wider tire. Since I don't actually need the tires right away, I'll wait until I get closer to completion before ordering new ones. I'll order up some new wheels, brakes and axles from Matco. Once I have them I'll be able to get a better idea on the actual fitment.

  Dec 14, 2019     Prepped landing gear pins - (1 hour)       Category: Landing Gear

Cleaned up bearing area on pins that connect linkage to landing gear. Drilled through threaded end to permit a cotter pin to pass through.

Cleaned up and painted landing gear plates for RH wing. I don't need them for a while but I was on a role.

  Dec 12, 2019     More test fitting - (1 hour)       Category: Landing Gear

Although I'm still waiting for some critical pieces to be machined by Pierre, I was able to assemble everything for the landing gear as though I did have the missing pieces. There's a critical pin that connects the pitman arm to the link that connects to the landing gear. I'm hopeful that Pierre will have it done within another week. Instead, I mounted the link to the crank arm with a wooden dowel and held it in place with screws and oversized washers on either end. This allowed me to cycle through the landing gear by rotating the input shaft to the landing gear gearbox. I also identified the direction that the torque shaft will turn during operation. (Top will move forward, towards the leading edge of the wing, similar in direction to reducing the throttle on a motorcycle). This identified the direction the crank arm will move (counterclockwise).

By rotating through full travel operated by the gearbox allowed me to see full travel and all clearances required. Everything looks good, even with the nylon sleeves mounted around the springs. After I'd cycled things I spent some time to clean the nylon sleeves. They had dirt on them that had been there for 40+ years. I should have done it previously but I didn't realize how dirty they were until I grabbed them for the test fit.

I was also able to turn the AN5-80A bolt around such that the head was in the wheel well bay. I wouldn't have been able to remove it the other way, once the skin was on.

  Dec 02, 2019     Retract gearing torque tubes - (1.5 hours)       Category: Landing Gear

Worked on torque tubes that operate retract gearbox. Cleaned up surface discolouration and burrs. Realigned ��ingers��on end of damaged torque tube. This tube was damaged in the accident. Obviously from the RH wing which was destroyed in the accident. The universal joint fingers on this tube were spread slightly and tube was bent significantly. I won't be able to reuse this tube and to machine of a new tube would be quite an undertaking. These torque tubes are also beautifully made. The assembly is comprised of two tubes, one sliding inside the other. The inner tube has external splines machined partway down the tube. The outer tube has matching internal splines machined at the end of that tube. The tubes slide in and out and when connected on either end, the splines line up such that when the inner tube is turned, the outer tube turns as well. No play whatsoever in the assembly. To get the splines in the outer tube, they would have started with a thicker walled tube and machined it down to a smaller external diameter except where the splines are. A lot of work. So I'm going to have to figure out a new way to actuate the RH retract mechanism. Besides, one of the universal joint balls is missing. It's long gone. Checked the condition of the bolts that are part of the torque tube. Other than a bit of surface rust on the head, they are in good condition. Removed the rust, repainted and then sprayed the bolt shank with surface protectant.

  Dec 01, 2019     More parts prep - (1 hour)       Category: Landing Gear

Removed the metric threaded bosses off the second landing gear backing plate as described initially on Nov 25th. Cleaned up the plate and the additional plates that are part of the landing gear. Painted them with a rust primer. Awaiting special length AN5 bolts from AC Spruce and from Airfasco, then install!

  Nov 27, 2019     Travel contact switches and mounts - (1 hour)       Category: Landing Gear

Worked on retract mechanism some more. Had a good look at the electrical switches used to indicate retract travel. These switches are strictly used to illuminate the lights on the panel to show if the gear is UP or DOWN. Not surprisingly considering where this plane was designed and built, these switches were made in France. Interestingly considering the age of them, a couple of these switches still work and a couple of them don't. Surprisingly, these exact switches are still available! Online sources like DigiKey have hundreds of them in stock. Easily replaceable.

The first photo shows the switches mounted on the RH gear assembly with the switches mounted. It'll need cleaning in the future. The third picture shows the pieces that were made to mount these switches to the gear retract assembly. The shorter, curved pieces mount into a channel machined into the assembly housing. They are wedge shape such that when the plate is mounted above and the screws are tightened, the shape wedges itself tighter into the groove preventing any inadvertent movement. Notice too that the screws pass through some bushings. Two of the bushings have their hole offset from centre. This eccentricity allows the builder to mount the switch on the curved plate and then rotate the bushing to set the distance as required. To adjust the location of the switch, the plate is rotated around the retract housing with those wedges riding in the machined grove. Once again, beautiful pieces that were much more complex than necessary. A simpler way to mount them would have been to have a simple bracket with some elongated holes to allow adjustability.

I ordered the AN5-80A bolts required for landing gear mounting. I need four of them, two for each wing. These are significant bolts because they are the second longest AN5 bolts available. Imagine 5/16" diameter bolts that are over 8" long. AC Spruce couldn't source them so I found a manufacturer for them that sells them for $15 US a piece. During my search, I'd found a couple of places who offered to source them for me. One place quoted me $2500 per bolt! Needless to say, that place is off any future search list of mine.

I also placed an order for some AN5-60A bolts from AC Spruce for the other mounting holes. I need 22 of those bolts (11 per wing) and AC Spruce can provide them. These bolts are a measly 6" long.

  Nov 26, 2019     Disassembled gear legs for rebuild - (1.5 hours)       Category: Landing Gear

Removed gear from wing. Disassembled gear leg assembly to take lower gear leg with damaged fork to welder/machinist friend to inspect. Need to start planning gear leg with new brakes, wheel, and tire to fit within wing.

Upon discovering the corroded landing gear mounting bolts, decided it's prudent to inspect all bolts.
Removed bolts on gear retract shaft. Bolts looked fine but cleaned them up, repainted the heads, and put in new safety wire. Much better.

  Nov 25, 2019     Parts cleaning and Prep - (2 hours)       Category: Landing Gear

I had a few questions regarding the servo tab on the aileron. I've attached a few photos of it to help explain. The role of the servo tab is to lighten the control forces on the stick. Light control stick forces is something desirable on aerobatic planes. A lot of aerobatic planes have spades on the ailerons to lighten the loads and a servo tab on the elevator. I guess Dalotel wanted to use servo tabs on the ailerons as well. The servo tab works by automatically moving in the opposite direction to the travel of the control surface. Check out the attached pictures and you'll get a better idea.

Also note the addition of the metal plate added to the original tab. This plate extends beyond the trailing edge of the aileron and more than doubles the surface area of the tab. I don't know when in the plane's life that this was added but I'm sure it was helpful. Those original tabs were pretty small to begin with. You may have noticed that there's a 90 degree bend with a 1/4" flange perpendicular to the airflow at the trailing edge of that extension. I'm going to have to speak with an aerodynamicist friend to inquire about that bend and see what he thinks about it. Maybe it was just to stiffen the edge of that plate.

I identified more parts and did some more cleaning. I also worked on the landing gear backing plate. I drilled out the integral threaded bushings to allow a 5/16 bolt to pass through. I then cut off the majority of the bushing depth and finished the plate to allow conventional stop nuts to be used. I took a wire brush and removed the last of the 50 year old paint and then cleaned and repainted the plate in my home made paint booth. The booth is a large plastic tub that sits on its side with a bathroom fan mounted on the tub's bottom and a furnace filter stuffed in front of the fan. It does an tremendous job at keeping the overspray to a minimum.

  Nov 24, 2019     Hung Landing Gear and cycled through retract - (1 hour)       Category: Landing Gear

Removed bolts that were holding the landing gear mounting plates in place and discovered that the bolts had some corrosion on them. Time to replace them too. They were custom made by Dalotel, and I'm going to replace them with some brand new AN5 bolts. My order for AC Spruce is building. The challenge with replacing them with AN bolts is that the backplate will need to be modified. The backplate currently has some custom made nuts that are press fit into the plate that Dalotel's bolts thread into. They're kind of like nutserts but more robust looking. I'll have to remove those nuts and use normal AN365 nuts. See attached drawing. In fact, the drawing shows nuts in addition to the press fit nuts. This is another case where the drawings and the actual build are not the same. All the bolts with the red circles will need to be replaced. The pin in the yellow circle is also custom machined. The threaded end of that pin was broken off on each of the existing landing gear legs. I suspect they hammered them off to disassemble the landing gear after the accident because the pin itself is fine and the bearing that it fits into is fine. I'll have to order some bar stock from AC Spruce and put that on the lathe.

I assembled everything today and cycled the landing gear through it's motions. It required a few extra hands (and feet) to operate. The video's a little rough but hopefully it helps explain how the retract system works. Assembling everything helped me identify some of the unknown parts and how it should go back together.

I guess the video isn't going to load. Sorry about that. I'll see what I can do to about that in the future.

  Nov 21, 2019     Reinstalled landing gear gearbox on LH wing - (0.5 hour) Category: Landing Gear

After cleaning up and prepping some of the mounting area I installed the gearbox assembly. Used original bolts to hold it in place for now. Chased threads on bolts and nuts to allow easier threading. M8 threads. I will replace these bolts with AN5-60A and AN5-80A bolts when sourced. AN5-60A bolts are available from AC Spruce for about $14 Cdn. per bolt. Not cheap for a bolt but let's see. Awaiting quote from AC Spruce for the AN5-80A bolts. I got quotes elsewhere for those bolts. One company quoted me a pricy $125 per bolt. I thought that was crazy until I received a quote from a second company. $2500 US per bolt! I'm sorry but that's absolutely ridiculous. If you don't want that business, just decline to bid.

  Nov 20, 2019     Messing with retract system - (2 hours)       Category: Landing Gear

Started prepping the retract gearbox for LH wing. I had done a quick cleaning on the retract gearbox when I unloaded and did inventory. I really cleaned it well today using a brass bristled brush and some brake cleaner and rags. The gearbox is truly a work of art. It's a shame that it will be hidden away in the wing once done. It's amazing, even after 50 years it still runs as smooth as butter.

The retracts are operated by a single motor in the fuselage. The motor runs through a gearbox with outputs running outwards towards each wing. Each of these outputs are connected via a torque tube to the smaller splined input shaft of this gearbox. This gearbox is mounted behind the spar and a shaft runs forward, through the spar to a series of levers that raise and lower the gear. See Nov 4 entry for a brief description of the operation of this unique retract system.

This gearbox is geared 37:1. That is, the input shaft must complete 37 turns for 1 single turn of the output shaft. Lots of mechanical advantage there. It will be interesting to figure out the ratio of the gearbox that's in the fuselage that takes the motor output.

This gearbox is mounted to the backside of the spar with 4 bolts that run through to the pad/bushing on the front side. The bolts for this plane were custom made by Dalotel. Just like everything else on this plane. I've found drawings of these bolts in the 300 pages of drawings. They are effectively AN5 bolts. I'm going to replace them with new bolts as these ones are showing some surface corrosion. The "shorter" ones can be ordered as AN5-60A from AC Spruce. The longer ones would be AN5-80A, the longest AN5 bolts made. It looks like those critters are available but they may have to be sourced elsewhere.