Pilot Shoulder Strap Clip

Time: 2 Hours

One thing I have read about is the complaints of how the pilots shoulder straps don’t stay into position on the roll bar behind their seat. The straps are held on with a loop of the strap around the roll bar. Since the roll bar extends outward for a little bit and bends downward the straps have nothing to retain them and can slide outward. This means you have to fidget with them to get them into position. Big deal? No but since I have time on my hands I decided to come up with a solution. In the shop I have these wall units that have a bunch of little drawers in them. They are clear plastic and house all my rivets, screws and so on. I have had them since I started my build. Anyways these set of drawers came with these flat clips on the back that you could use to hang on the wall. These clips were meant to slid into a receptacle that would get screwed to the wall. I held on to these receptacles for some reason. While I was digging thru some parts I found them and a light bulb went off. They were the same width on the inside as the width of the shoulder straps. So I devised a plan to screw these to the underside of the roll bar to hold the straps in place. You may be having a hard time picturing these but in the following photos hopefully they make sense. First I did some test while sitting in the seat as to where I wanted these to align on the roll bar so they were comfortable. Then I marked the location and removed all the parts. I fine tuned the marks on tape that I put around the roll bar to protect the paint. To get the two holes aligned and marked for drilling I attached them to the roll bar with zip ties. In the photo you see the clip zip tied with two small washers taped to the clips. This was to make up the space of the clip so the zip tie didn’t squeeze the clip too much so I could get a good mark on the holes.

Now you have an idea what these clips looked like. On each end is a hole that’s countersunk for a flat head screw. This hole fits a #8 screw perfectly. So I marked the holes through the clips onto the tape after I had them aligned along the roll bar. I removed the zip ties and the clips and drilled and tapped for #8 screws while laying down inside the fuselage. I tell you having a bunch of Harbor Freight moving blankets is key to protect your back from all the protruding parts. With the holes drilled, tapped and cleaned up I put then shoulder straps in place and attached the clips with screws.

Another little project done and making progress. Simple yet effective solution to a problem.

Canopy Skirt Seal

Time: 2 Hours

Earlier on in the canopy build I installed a felt strip running along the inside bottom edge of the canopy skirt. This was supposed to help seal the gap between the skirt and fuselage when the canopy was closed and reduce wind infiltration. After the canopy was all done I wasn’t happy with the end result, at least how it looked. So while I had the canopy off to Pro-Seal the aft end I decided this would be a good time to fix it. So I worked for 1.5 Hours pulling the felt off, rubbing and using Goo-Gone to get all the 3M adhesive off. I worked slowly so I wouldn’t damage the paint while I removed it. After I cleaned the skirt up and had all the residue removed I replaced the felt with a adhesives backed 1/8” x 1/2” foam strip. Here is what it looks like now and I’ll see how it seals when I replace the canopy back on the fuselage.

The nice thing about this stuff is that it will be easy to replace when needed.

Pro-Sealing

Time: 3 Hours

I removed the canopy structure and flipped it over into the cradle. I have a slight “squeak” when the aft section of skirt moves. It sounds like it’s the fiberglass skirt rubbing or moving ever so slightly on the canopy. So I decided that I would fill the gap between the skirt/canopy and the canopy/frame with pro-seal. I taped it all off to protect the areas that I didn’t want to get a mess on. I also taped of the inside of the forward baggage area were the top skin meets the firewall for sealing that gap while I was gonna have the pro-seal out.

I bought the premeasured type from Aircraft Spruce that fits in the special gun.

After the required mixing I went to it making sure I had all the required items out for clean up including the MEK and tons of rags…this stuff is messy!

With a quick pull of the tape while it was still wet I had nice clean lines. Hopefully the squeak will be gone once this cures in a few days.

SkyBolt Install

Time: 8 Hours

I need to explain to those who are unfamiliar with how the RV-8 has its fiberglass cowl attached to the aluminum fuselage. The stock way of doing this is with piano hinge mated to the aluminum and fiberglass using the center pin to hold both halves tight together. This has worked well on thousands of RV’s out flying. There are challenges to this method, including difficulty getting the pin in and out when removing or replacing the cowl. Especially along the top and bottom of the cowl due to the curve. Another option out there is to use the Skybolt fastening system like many production aircraft. Even the Lear 45 I fly has similar fasteners holding the avionics doors in place. The Skybolt system uses receptacles mated on the fuselage and spring loaded pins mated on the fiberglass. When the two parts are brought together the pins get pushed in and turned to lock into the receptacle. These make installing and removing the cowling incredibly easy and reduce the risk of chipping/scratching the paint that’s usually associated with the hinges. I decided early into my build that I like the look of these fasteners and would use them on my RV-8. So like many projects in the build in order to do one task there are always other tasks that need to be finished first. I started out wanting to seal the firewall inside the baggage area and realized that I needed to have the Skybolt tabs riveted in place first. So that’s what led me to this task. Show my goal was to get The tabs riveted along the top curved edge of the firewall leaving the sides for later. The cowls have two main sections when it comes to the Skybolts, the perimeter of the firewall and to sides of the cowl the run from the nose aft to the firewall. The goal will be for the aft Skybolt of the sides, running from the nose aft to the firewall, will be in sync with the perimeter Skybolts. That way everything looks symmetrical, this will be much easier to show later on in the billed as I get to that stage. But for now I have to do a lot of planning so that that winds up. I will have some lead way in moving the tabs to get that all to work if I leave one or two tabs above the center line open. Those will be able to be moved or spaced so that all line up just right. For now I just need to be close so that a 1/8″ here or there won’t be noticed to get the spacing right. So for now I started working on the tabs which included cleaning up the edges and countersinking the holes that will attach the receptacles.

To start I’m going to center one tab, dead center of the top of the firewall. From there I will work my way outboard until I get to the sides and see how the spacing looks.

As I worked my way outboard I need to find out a rough area for the centerline of the cowl. I got a pretty close location mark with the help of my buddy Glenn. With that mark I was able to figure out the line that would represent the centerline of the Skybolts that will be above the cowl centerline.

With that one tab set I adjusted my spacing on the remaining tabs between this one and the top one to get even spacing. Once I was happy with this I removed the two lower tabs on both sides as I will drill those later. Then I match drilled the tabs with the firewall and forward skin.

I marked each tab with a piece of tape and a number so that I could replace them exactly where they go. After drilling I remove them all and deburred the holes. I also countersunk all the holes on the forward skin for flash rivets. After all the tabs were returned to their correct spots I used my pneumatic squeezer to rivet them all in place. Keep in mind I left the lower couple of rivets on the lowest tabs out so that I could get the next tab in place once I need to. My goal is that I will have some wiggle room up or down with the remaining tabs to get them aligned with the ones that will be on the cowl sides. That way they all look symmetrical. I made quick work of riveting the tabs in place after getting all the holes cleaned up.

After those were finished I moved to the bottom of the firewall. Here there are two small areas that would normally have small hinge sections but will now have two Skybolts.

I added a small piece of .032″ aluminum to the corners to close up the gap that will be between the cowl and firewall. It should also help align everything when installing the cowl. I cleaned up all these holes and got them riveted as well. Slow progress only because I have so little to do and 55 days until I go build my engine.