Today we removed the baffle clamps, and checked the filler had set correctly. It all looks good!
Baffle Clamp Strips
Baffle Clamps, air ramps, & JDAir Latch
Today I worked on fitting the JDAir latch mechanism into the slot, including installing the “dummy” rivets which only fill the existing holes and don’t clamp anything together. One of these rivets interferes with the latch, so a countersink is needed on the latch mechanism to work around it. With the countersinking done, I was able to fit the bottom bracket, and match drill the new rivet holes into the fuselage. Once I cleaned up the holes, I dimpled using a pop rivet dimple die. They never dimple very well, but there’s not much I can do.
Meanwhile, Dad worked on sanding and fitting the air ramps to the top cowl. These are basically ready to be epoxied into position now.
We also shaped the air inlet baffle seal clamps. Once these are bent to shape, they are wrapped in packing tape, and filler is applied to the inside edge of the cowling air inlet. The clamps are then used to form the correct shape. We did that, and will let it set overnight.
Cowling and Exhaust
Today we continued working on the cowling and the exhaust system.
While Dad handled the sanding and fitting of the cowling, I worked on setting up the exhaust system. First I assembled the support clamps, then applied anti-seize lubricant to the sleeve and ball fittings, then set it up underneath the engine.
With dad’s help we were able to mount the pipes onto the cylinders, doing up the hardware finger tight.
Using a roll of 3/4 inch electrical tape, I set the spacing correctly and installed the support clamps on the aft edge.
Dad did another round of filling today, as there is still a ways to go to achieve the alignment we need on the cowling air inlets. It’s amazing to watch him work, knowing just what’s needed to get the perfect fit and finish. At 79 years old he’s still putting in very long days, with no complaints.
Cowling Air Ramps, Exhaust, and Oil Door
With my dad back in town and helping with the cowling again, we made progress today on a few fronts. Dad worked on installing the top cowl air ramps, and started on the oil door, while I focused on the exhaust system.
Before the air ramps could be installed, we needed to address the alignment issues with the front of the cowling. In a couple of sessions, Dad applied filler to the edges of the air inlets, and trimmed the air ramps to fit.
Meanwhile, I installed the first section of the heating system, the heat t-fitting. I left the clamps loose for now, as it’s hard to tell if this will need to be finessed into position later. I then drilled out a couple of rivets, and installed the FF-00084 cover. After some puzzling, I realized that this stops the hot air from escaping the system when the passenger vent is closed, and the pilot vent is open.
We then found and trimmed parts for the oil door.
Cowl Fitting
Last night I attempted to address an alignment issue on the right hand air intake. The outside edge was not lined up, so I added several layers of glass on the inside of the top cowl in the area near the prop. Tonight I test-fit the cowl. The good news is that I fixed the alignment issue, the bad news is that I introduced an equivalent alignment issue on the other side. I’m going to leave this for now and come back to the cowling at a later date.
Cowl Fitting
Today I cleaned up the excess filler by using a small chisel to gently scrape it away.
With that done I was able to fit both pieces of the cowling in position and confirm everything lined up as expected. It looks good!
Bottom Cowl Hinges
Today I riveted on the bottom cowl hinges. The boe-lube worked well as a release agent, and the clecos came out easily. With the hinges glued in place, I cleaned out the excess resin by running a drill through each hole. Before glueing I inserted the hinge pins, just to help avoid any deformation, and I left them in while riveting.
Progress was swift, and I had the hinges done within half an hour. I went to test fit the cowl, but found I couldn’t get the aft edge hinges to line up with the firewall-mounted hinges. Pushing the cowling back caused the cowling to bend outboard instead of seating into position. I took the cowling off, and realized that I had some excess glue between the hinge eyelets on the left hinge. This happened because I used filler to build up a bed of glue behind the hinge where it interferes with the foam section. I’ll try to clean it up tomorrow somehow.
Bottom Cowl Hinges
After clearing the excess resin, I started riveting the hinges on the bottom cowl. Immediately I realized I needed to first glue the hinges on, not just rivet these. On the aft edges, the interference between the hinge flange and the honeycomb meant that riveting the hinge could cause the rivets to tip, and leave a cavity between hinge flange and cowling. I mixed up some resin and glued all of the hinges into place. As a release agent, I used some Boe-lube on the ends of the clecos holding the hinges.
Riveted Top Cowl Hinges
Tonight I riveted the top cowling hinges on. I first cleared excess resin from the holes by running the drill through the holes. Then I clecoed and riveted the hinges on.
One thing I didn’t do on the top cowl was glue the hinges before riveting. The plans didn’t call for using any epoxy, and I decided it wasn’t really necessary.
It didn’t take too long to knock out the riveting. Once done, I mixed up more resin and coated the inside of the bottom cowl.
Cowling Work
Today I coated the interior of the top cowling with a layer of resin. This helps seal the cowling and makes cleaning oil and grime easier. I mixed up the resin and brushed it on.
