Main Landing Gear

Time: 4.5 hrs

Things done today:

  • Fill primed and sanded main gear
  • Fit back of main wheel spats to wheel spat brackets on left and right main wheels
  • Filled unused holes and blemishes on back part of main wheel spats
  • Mounted axle to main gear
  • Moved brake bleeder on left caliper to bottom

Finished up priming and sanding the main landing gear. I used a fill primer and did about 3 or 4 heavy coats. I then sanded with 320 grit paper. The sanding paper gets clogged a bit, but worked well. Only a few small blemishes in the gear now and the ends are all primed. I also primed a bit more on the top side as well since it looked like they didn’t paint enough there either.


All nice and smooth and can’t really see the seam where they stopped painting.

 

I also did some work fitting the rear part of the wheel spats to the brackets on the main gear. This ended up being a lot of work and more work still needs to be done after I mount the gear and get the wheels on. I had to bend the tabs on the brackets in a bit to get the rear spat piece to sit a bit closer to the landing gear. There’s still about 1/2-3/4″ of a gap, but I think it will get pulled in a bit when the front part of the spat goes on. One thing to note is that you shouldn’t use the pre-defined indents on the spats to drill the holes because they don’t really line up. I was lucky with the left one, but kind of messed up the right one (am going to try to fill the part of the hole that’s not needed). If you are using the newer spat bracket (the one that lets you remove the brake caliper) then you definitely won’t use one of the pre-defined holes because one of the screws is in a completely different place. So just pick one of the two front pre-defined holes and drill it out. Get the screw in and mount it to the bracket, then set the part the way you want and mark the location of the new holes from the back of the spat (through the back of the rivnuts). The holes will be close to the pre-defined ones, but off enough). You can only get the top of the rear spat piece so close to the gear because the piece hits one of the bolts ends that holds the axle onto the gear. I tried using a shorter AN4-21 bolt and a thin AN4 washer but it was just a bit too short (you should have at least one thread after the nut).

Outside of the left spat mounted to the gear (upside down). You can see the unused hole just to the bottom of the bump out (to the left of one of the mounting screws) on the spat. This would normally have been used with the older style mounts, but I have the newer spat mounts. The rear part if the spat is mounted using 5M screws and 222 loctite. I purchased 5M X 12mm Class 12.9 Alloy Steel screws from Bolt Depot since I didn’t have any screws with the kit.

Inside of the rear spat. It’s a very close fit to the brake caliper.

The axle went back together pretty quickly since I had test fit everything before. The only change I made was I used thick AN4 washers rather then thin ones called out in the manual because the nuts were bottoming out on the non threaded part of the bolt.

All primed, axles mounted and bolts torqued to 7ft/lbs. I’m wondering though if this will all have to come apart when the gear gets painted.

Close up of the left axle mounted to the gear. I had to remove and reinstall the bleeder valve on the left caliber so that it was on the bottom. Also the caliper is only in the top hole. The pins should go in the two holes in the axle.


The garage is a disaster. I need to move the tables out and build some saw horses. I’ll then get some friends over so we can flip the fuselage upside down. Then I’ll fit the main gear, install it and rivet the gear skin. Lastly I’ll fill and sand the rivets. I’m hoping the plane will fit with the engine mount. I think it will 🙂

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Right Fuselage Rivets Filled

Time: 4.5 hrs

Finally was able to get back to working on the plane after some family events. Today I filled and sanded the right fuselage side. Now that the fuselage is on the ground it’s very easy to move it from side to side to fill the rivets. The tough part will be to turn it upside down so that the bottom rivets can be filled. I’m still not totally sure how I will do that.

I also worked on the main landing gear a bit. The factory didn’t prime all the gear and there were some spots that need some filling and sanding. I still need to do a bit of work on it. After it’s primed I’ll put the axels on and get it ready to mount in the plane.

The ends weren’t primed so I need to clean them up and prime. This part is under the wheel spats, but it will eventually get painted so it needs to be primed now.

More Filling and Sanding Rivets

Time 1.25 hrs

Just filled and sanded some rivets on the top of the rear fuselage. Not too many rivets so it didn’t take too long. Next I need to roll the fuselage over to the left so I can fill the right side. After that is the hard part of rolling the fuselage over so I can fill the bottom rivets. I’m not exactly sure how I’m going to do that yet. I’m thinking of maybe hanging it from the garage rafters with some straps with Come-Alongs.

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Here’s what I’ve been using to sand the rivets. I’m also using the tool I made (posted in a previous post) that protects the skin when you are sanding the rivet. It’s very quick to sand off the resin. I just sand until I see the rivet get a little brighter which means I’ve sanded all the resin off that doesn’t need to be there. Don’t sand too much because you can sand down the actual rivet. The only issue I have with this is my drill weighs a ton so ideally it would be better to use a lighter drill. I originally was thinking that you want a high RPM drill, but I end up running my drill at around half speed anyways so probably around 800-1000 RPM. It makes the process a bit more controllable with slower RPM.

Main Gear

Time: 1.75 hrs

Wow I figured I’d quickly put the axels on the main gear… well it took a bit longer then anticipated. There was one bolt on each side that seemed to have been drilled out a little off in the main gear (at the factory) so that made putting the wheel spat bracket on very difficult. I did manage to get everything together after some gentle hammering. It should be fun taking it apart again. Also it seems that the factory didn’t prime the whole gear so I’m thinking I should prime everything.

Note: I assembled this with the main gear upside down… which makes it even more fun   :-). I flipped the photos over so that it’s a little easier to get the orientation. If you notice things hanging from the ceiling that shouldn’t it’s because of that.

Everything assembled looking from the axel side.

Assembled looking from the wheel spat bracket side (inside). finally got that sucker on. Also you can see the M5 rivnuts installed in the wheel spat bracket. This is the newer bracket which gives you access to remove the brake pads without having to pull the whole wheel apart. The old bracket is wider in the back and covers part of the caliper.

You need to align the axel and brake caliper bracket so that one of the holes for the brake caliper bracket lines up with the cut out in the gear (top right of photo) otherwise the brakes won’t fit back on.

Sanding Rivets

Time: 2.75 hrs

Today I sanded the left side fuselage rivets that I filled yesterday. The process is a bit slower then filling them, but still moves along pretty quick. No real tips here, just don’t sand too much. I made a tool to protect the skins when you sand the rivet. I made the tool with two different size holes (one of 4mm and the other for 3.2mm) but you really only need the larger one since the sanding disc won’t get in between that small gap. The width of the tool (about 1-1.5″) was pretty good. I was able to get in between most rivets and have the tool sit flush on the skin. A few places I just had to be careful with the sander and not use the tool. And the few countersunk rivets needed to be done with care as well… just a few light scratches on the skins.

This is what I’ve been using to fill the rivets and the tool I made to protect the skin when sanding. I’m using a small 3″ sanding disc on my electric drill with 240 grit paper (will need to get a photo of that).

 

Filling Rivets

Time: 1.5hrs

Started to fill the fuselage rivets. Yesterday we had a party at the house so what better way to get some help to move the plane. I rounded up a few friends (before we starting drinking) and we managed to lift it and gently place it on its side on the ground. I bought some flotation noodles which work really well to keep anything from getting dented or scratched. I was able to fill the whole left side today so I don’t think it’s going to take as long as I was expecting. 

The process goes pretty quick. Most of the time is spent mixing small quantities of resin, hardener, and talc. I’m mixing very small quantities because you can’t use that much by the time it starts to dry. I use about a teaspoon or resin, 4 drops of hardener and about a teaspoon of talc. The talc is just to make it a little more pasty. You don’t want it too pasty because you want the resin to flow and fill down into the rivet. I use a plastic (Chinese style) chop stick to dab the mix onto each rivet. Just a few notes that I should mention about the process:

The process requires gravity to be on your side so whatever you want to fill needs to be somewhat flat and horizontal. 

Make sure to put plenty of resin mix onto the rivet head. When I started I was being stingy and not using much. However the resin does seep into the rivet so if you don’t fill enough then it may dimple in the middle and you’ll have to add more. This is mostly on the larger 4mm rivets and for some reason the countersunk rivets. 

Don’t fill your static port 🙂 

The mix. This was the first one I made so I made way too much. Also in the photo is the chopstick for dabbing the mix into the rivets which also doubles as the mixer. 

The plane on its side. One noodle cut in half was used. I just put them under the front fuselage at about 3 and 6 feet from the front. 

Filled rivets. Will try out sanding tomorrow. 

Main Wheel Spats

Time: 2.25hrs

Worked on fitting together the spats for the mains. I followed the same procedure as was done on the nose wheel… clamp and tape into place, drill pilot hole, drill 4mm hole then use the hand reamer to ream the inside hole to fit an M4 rivnut. These didn’t seem to come out as well as the nose wheel spat. I couldn’t get the join to sit flush and having to put in the rivnuts made the seam even more pronounced. I’ll have to look at the ones at TAF to see if the job I did is acceptable. I think they came out pretty good so I’m probably just being a bit too picky. 

Finished. The tops will need to be cut down, but I’ll need to fit them into the main gear to see how much to cut. 


A little closer photo.