So the Strega was built and flown on a ro-jett 61, and then i believe a .75. But no pipe. I want to run a ro-jett 61 on a pipe. Because it was built with no pipe in mind, i am now tasked with installing a hole... Haha.

Before getting started, i decided to make a tunnel out of foam. If nothing else, it's a good starting point for a mold. I'm thinking of slotting the belly, installing the foam tunnel and light glassing it over. Then paint it to match. Sounds easy enough i suppose...

How warm do things get around a pipe?  CF-epoxy can survive much higher temperatures than foam.

Just thinkin', here -- dunno if it's a valid worry or not.

All excellent points. I don't know about temp... The main thing i wanted the foam for was just a shape. I'm thinking more and more it's only going to be a mold to make a fiberglass tub.

For the fuse rigidity, I'll add formers that are shaped to the tub, and inside the fuse.

...

All excellent points. I don't know about temp... The main thing i wanted the foam for was just a shape. I'm thinking more and more it's only going to be a mold to make a fiberglass tub.

     It doesn't get that hot towards the back. I would suggest you leave the foam in place, put medium glass over the foam, and move on with your life.

    BTW, the danger point where anything will melt, if it ever will, is about a minute or two *after* a flight

      Brett

Doesn't Dubby have a mini muffler for that?  I have one on the Ro-Jett 40 RE.

It's a Randy pipe Dave. Here it is laying into the chamber i cut. I'm thinking my thoughts of the job were bigger than what the job is ending up being. The entire section of the fuse was hollow enough to accommodate the pipe. I'll use a Macs pipes mount basically on the wing inside the fuse. Then just box in the hole i cut as you described. I'll clean up the cut out with a dremell and sand paper. Should come out pretty good.

Doc, i thought about the mini muffler, but i bought a ro-jett so i figure I'll make the most of it. Dive all the way in, you know?i could have just bolted in my k&b 61 or the saito 72 fs and made it really simple. But i just wanted to learn how to tune a pipe set up.

Oh, and pic two shows the only former in the way. I'll notch it down about 3/16 and it'll clear the joining area

Ok, here it is before the paint. I just boxed in the area. The pipe mount is a piece of 1/2x1/2 hard wood jb welded to the wing (which was glassed). I cut it to the same angle as the wing, so the top mount portion is parallel to the pipe. Then the mount piece is bolted to that hardwood.

Hey Charles. I'm just using my phone camera.
I wanted to just leave the pipe outside completely, but the header sinks into the fuse, so the pipe had to be lower. I didn't build this plane, it's pretty descent but not too pretty anymore. Lots of flight hours. Seen a fair number of contests too. So i know the plane flys. Great test bed to learn about piped engines!

I guess that depends on the size of the pipe? Oh!

Oh, and i glassed it after sanding a lot. It came out better looking than that, but i don't have a pic i guess. I'll get it after paint