Rear Bulkhead Mod Done

Time: 4 Hours

I spent a couple hours this morning finishing up all the little tasks on the mod. I finished up the work on the notch on the top and deburred all the holes. I did decide to go with 3 CamLocs rather than the 4 I originally drilled for. I didn’t like the way the panel sat when I put pressure in the 4 spots I had, mainly the top corners. So I moved one to each corner and one dead center at the top. I had only drilled the rivet holes for the 4 so I will just dimple those and put a rivet in them, they will be covered up by the panel and will just add to the strength of the doubler. Once I drilled the new rivets for the CamLocs I used a #21 bit to drill down through the CamLoc main hole and into the doubler, upper bulkhead and the panel door. This allowed my to keep all the holes aligned. I then used my unibit to enlarge the door holes to 1/4″ and the bulkhead/doubler to 3/8″. The CamLoc stud won’t fit through the 1/4″ without compressing it. I bought a special pair of pliers just for this job. You can the rock the stud into place and release the pliers and it will stay in place. I will also add some retaining star washers that will hold the stud firmly in place so it won’t wobble around.

I then checko’ed the hinge and the platenut the will hold the hinge pin in place. I used the 3 CamLocs to hold the top of the door in place for now. I still have other work to do before I can prime and rivet these parts. All in all a fun project making a mod that will be really helpful down the road.

With all the paint on the gear towers curing and this mod done I decided to stop the work for the upcoming Labor Day weekend. When I get home from the ling weekend I will finish up the tower riveting so I can start on the forward baggage area. Have a great holiday weekend!

Rear Bulkhead Modification

Time: 6 Hours

I got most of the painting done on the gear towers the other night and will finish that up tomorrow. If you don’t get your second or third coat of Rustoleum on with an hour of the previous coat you have to wait 48 hours before re-coating. This is to prevent wrinkling of the next coat as there is a chemical process going on between the outer coat, which drys faster than the under coat. If you try to re-coat after the first hour you essentially have a wet coat on top of a dry coat on top of another wet coat. This lends itself to bad wrinkling. So with all that said I let the gear towers dry for over 48 hours and can re-coat them tomorrow. While I was waiting I decided to start the process of modifying the rear bulkhead for an access panel to make working on the avionics much easier.

This panel divides the forward baggage compartment from the avionics bay. There is an upper and lower portion. To work on the avionics under a normal build you would have to remove the instrument panel or crawl under the panel to gain access. A modification that makes that task easier is to cut out a hole in the upper portion to make access to the avionics easier through the baggage area. I took many notes and pictures from my buddy Glens -8 as well as several at OshKosh this year. I laid out all the parts and did some marking of the cuts.

After going over each part in my head I finally started the cutting.

I cleaned up all the edges with my Dremal, sandpaper and my files. I had ordered some sheet stock from Aircraft Spruce, one of which was a 2’x2′ sheet of .040 thick Alclad. I used this to make a doubler for the area I just cut out to stiffen things up a little.

Once that piece was fitted and cleaned up I measured out the rivet holes to hold it in place as well as the rivet holes that will hold the CamLoc 1/4 turn receptacles on. I’m using 4 CamLocs for this door and they will make it real easy to open it when needed.

The next few steps were to cut some piano hinge the right length and match drill it to the lower portion of the hole. I then grabbed some .025 sheet and fabricated the door. It was mostly a little measure then cut then measure then cut.

Before I could close the door I need to make a notch in the top of the door to make room for the baggage door hinge support bar the gets riveted to the upper portion.

It was getting late so I decided that was a good place to stop. I will get back at it tomorrow and try and finish up this mod. Lots of fun making this airplane all mine but it’s a lot of extra work! 🙂

Gear Tower Riveting

Time: 6 Hours

I got back to working in the riveting if the gear towers this morning. The rivets on the face of the towers I was able to get with the pneumatic squeezer which last night I thought I would only be able to get with the gun and bar. I used several different yikes in the squeezer to get all of them through the lightening holes. Once I had those done I did the next few steps in the plans which ended up with the gear towers clecko’d to the forward floor section.

Having these towers in position allows them to be lined up and secure so you can rivet the exterior side gear weldements. These have a bunch if rivets, both forward and aft. I grabbed the 4X rivet gun and the AN470 head and my new tungsten bucking bar. I wrapped the bar and the spring on the gun to reduce the scratching of the primer. I started with the forward side rivets first, mainly so that I could get my riveting “legs” back and if I made a smiley on a rivet head it would not ever be seen! I love the new tungsten bar! I’m in the same group of people who say “I wish I had bought this a long time ago”!! What a pleasure to use, it’s just very dense and hardly moves as I buck and was small enough for getting into tight spaces. I got all the rivets done on the right side forward edge with only one smiley but it will never be seen. I moved on to the aft side and had great results with no smileys. I finished up the left side in about an hour and half.

I am skipping a couple of steps in the build process since I’m going to paint these as a structure before bolting the weldements in and riveting to the forward floor. I then matched drilled the two upper supports, forward and aft. Van’s plans make a big note to not change or omit these parts as they are structural. I have heard of guys altering these so that certain avionics could fit behind the instrument panel. I also checko’ed the lower side braces.

I then took off the braces and inboard weldements off and cleaned up the new rivets for priming.

I had to stop there as I have a 4 day trip to fly. I will paint these parts when I return and let them cure for a while before riveting them all together. Next up the forward baggage area.

More Gear Tower Work

Time: 8 Hours

Today started all the match drilling of the gear towers. There are a lot if holes and it takes a while to hit every one. I then grabbed the countersink to hit one rivet hole on each tower. These holes are under the edge of a bracket that get riveted later. I have read where guys have missed this step and have to drill out later.

Like the change in rudder pedals for the pilot I added the option for the rear seat rudder pedals. I knew that the bracket will get bolted to the gear towers so I grabbed that bag and looked at the instructions. It’s nice to read ahead as these normally get added later as an after thought and you have to drill in a tight spot. I’m able to drill the matching hole with everything apart which makes it a ton easier. Here is what the bracket looks like installed with one hole that they provide. You have to drill the second by using the existing holes.

As with everything else after you get it all together you take it all apart to deburr all the holes, scuff, clean and primer.

I spent the next several hours scuffing and cleaning the right side tower and started the priming on those parts. In between the coats of the primer I started the dismantling deburring of the left side. I finished priming both sides and let them dry for an hour while I ran to do an errand. When I got back I started the riveting on the right side. I did all the rivets I could do with the pneumatic squeezer since it was getting into the evening and didn’t want to bother my neighbors with the rivet gun. I also riveted all the nutplates on for the access plate.

Another great day in the Hangar!!

Cooling Ramp & Gear Towers

Time: 8 Hours

Today started with a few work related tasks and a couple of errands. When I got home I got right to the Hangar for some more work. First task to rivet the cooling ramp stiffener in place and the cooling ramp attach bracket to the forward floor substructure. The stiffener was done with the back rivet set and I was able to get the others with the pneumatic squeezer.

After that I moved on to the gear towers. All the parts need to have all the edges deburred as well as all the lightening holes. That took several hours to get accomplished. Now on to one of the “mods” I will be doing to my RV-8. When the gear tower is completed it is a pretty tight space on the inside. The main gear attach bolts will be housed inside of the tower at its bottom going through the floor to the steel gear legs. You have to check and torque these at a regular interval. Van’s only gives you a stretched circular hole in which to access the nuts for torquing. It’s well known in the RV circles that this is a pain in the butt to say the least. So down the road someone came up with a modification idea that would help this task. Basically it’s a access plate that opens this area up for access. There have been several different styles or mods that various builders have used. I decided to go with what was proven, my buddy Glens style, and did a rectangular panel. This will allow me to use the angle structure for the support and will just replace the stock rivets with #8 nutplates to screw the plate to.

So I took several measurements ant came up with a good panel size. The top will be at a slight angle as the rivets are not matched between the forward and aft sides. This will allow me to have the screw holes in a straight line although at an angle. Once I had the idea on paper I transferred the lines to the panels.

I then made the cuts on the band saw going very slow to make nice straight cuts. My blade made about a 1/16″ gap between each panel but that will be backed by a filler piece behind which will have a couple nutplates in it.

Once I had the access plates cut and cleaned up I needed to fabricate 4 pieces of aluminum to act as backers to the top and bottom of the plate.

With the plate backers done and fitting just right I moved on to the top and bottom pieces of the panel. I needed to mark out 4 rivets on the ends that match up with the access plate. These will be flush rivets and hold the plate backers in place.

I enlarged all the perimeter holes to a #19 that will accept the #8 screws. All of the perimeter holes will need nutplates for the screws to go into. That’s where my new tool, the nutplate jig, came in to play.

I was able to get the 16 nutplates drilled in 10 minutes, man I love this tool! I put all the parts back together and cleaned up the Hangar. That’s 8 solid hours of build time and it was a great day!