Dummy radial – part 2.

Finished up the dummy radial today. Didn’t buy enough of the stainless steel tubing so had to get one more piece – just a 40 minute trek across town for a $3.00 part!

Start of Dummy Radial detailing.

With all the airframe in a no-work wait period, I started a bit of work on finishing up the cowl. I painted the chin divider and now the rivets look good. Before, you couldn’t see them too much, but with the gray paint the stand out just right. Also, the inside of the cowl has been painted with silver Rustoleum to get rid of the fiberglass color.

I bought some metal rod and have figured out a way to inset the finished pieces into the radial – not just a flush-glue joint.

Using a Dremel tool, I’ve deepened the holes around the crankshaft and in each of the rocker covers. I can slip in the cut tubing into the crankshaft, then slide it out a bit to fit into the rocker cover. A bit of epoxy should attach it all.

The first rivets.

Well, among the other 9,483 things I’m doing for the first time on this model, rivets are one of them. With the wing drying from the latest primer coats, and the stab curing, I decided to experiment on rivets.

Our neighborhood literally full of housewives who are also nurses. I talked with one of them at the bus-stop the other morning and explained what I was trying to do, showing her a few pictures. I wasn’t sure what size needle I needed and she offered to bring me a few samples.

Well, I’ve been experimenting with different techniques and found that using a thicker craft clue (like Wellbond) or carpenter’s glue (like Tightbond) works very well. I originally tried regular Elmer’s, but the rivets looked like dried prunes instead of nice, rounded rivets.

So, using the tiniest of the needles (a 29 gauge), I found the combination I liked. Here you see the result of the first rivets. I used Tightbond and it works pretty well. Also, I can wash it out of the needle with a little work, so I can re-use it for the next application.

Muffler & exhaust finished.

Now I feel better. After reworking the muffler and waiting for the JBWeld to set-up, I think I have a pretty slick, scale-like exhaust system.

Basically, it’s a composite plumbing hardware (two 1/2″ 45° elbows, one 3/4″ to 1/2″ T, and a 3/4″ 90° elbow) with a bit of automotive reinforced radiator tubing to connect it all.

The copper fitting have a very tight fit into the plumbing and all joints have a coating of hi-temp automotive gasket sealant to seal it. The joint between the muffler and the larger tubing (forward of the firewall) will be the “removable” section after all is finished (just in case).

This shot is the first time I put it all together (including the spark plug ignition cap). It all fits just fine and should have plenty of clearance. Even better, I can still get the cowl off and on!

Dummy Radial fitted.

Lots of cutting, filing, cussing, etc., but the dummy radial is fitted.

Decided to mount it to the cowl, rather than to the engine mount. Easier to get on and off.