Inlet ring to plenum conection?

[bret]

Going to try my non artistic hand at shaping some foam for the diffuser connection thing to the baffle-plenum contraption, how are you guys making an air tight connection from the fiberglass to sheet aluminum? I would like to keep everything smooth and flowing without much of an overlap or joint?

[Mike S]

Anything here that could help?

http://www.vansairforce.com/communit...ad.php?t=43391

[bret]

I was watching Crabandy's build using Dan's rubber ducky mold technique, not sure if I want to tackle a new skill, just now getting the hang of FG, It looks like Dan used a Nutplate strip to sandwich the boot. I may be overthinking all this, been reading too much on here about all this cooling drag, baffle, plenum stuff, funny, starting the build 6 years ago I never even had one thought about this part of the build. now I need to stop and think what I should do here.....time to go spray top coat on baffle-plenum stuff and air out house before the wife gets home..........(What dear? what paint smell?).........

[WAM120RV]

Hi Bret

I made my own plenum and reshaped the inlets on the vans cowl to make them round. For a connection from the cowl to the Plenum I used some 3mm neoprene. It is cut so it fits over the cowl intake stub where I use a large jubilee clip to hold it in place.


The neoprene then sits inside to plenum intake to a depth of about 3 inches and is held by nothing more than its shape and air pressure. I used 5 inch diameter intakes on the cowl and T's and P's are spot on.

There is photo on the first place of my blog which capture this and a better one of the plenum about 5 pages back.

[Raymo]

I plan to do like another in my hangar, which is to use some neoprene or similar tubing material (flexible) to tie them together and allow for engine movement.

[BillL]

Having gone down the path of fiberglass inlets with the SJ cowl for use with the neoprene boots, I might go a different way.

I think there might be a good opportunity to make a hybrid approach. That is to make the aft 2/3 of the inlet in glass, then graft on a custom urethane boot bonded to the glass, and bonded to the SJ inlet ring. This given that I already have the ring glassed in. This way it is custom fitted to this plane, and no straight section needed for a clamp. A gentle expansion could begin much sooner. Even better if the inlet ring was shortened or modified.

Just a thought.

[868RM]

Maybe thin wall silicone turbo hose ?

[bret]

Got any Pics Bill?

[airguy]

Very interested in what you guys come up with, I've got the Sam James cowl and plenum and I'm not happy with the neoprene junction either.

[Carl Froehlich]

Originally Posted by airguy

Very interested in what you guys come up with, I've got the Sam James cowl and plenum and I'm not happy with the neoprene junction either.

I'm using a James cowl on the RV-10 as well. The first time I did the neoprene junction I was not thrilled with the looks. It worked for four years but they were not pretty. I called Will James and he walked me through the process (which was as provided in the instructions but I was too bull headed to follow them). I just finished doing a new set and they came out perfect. Total time was less than an hour.

The part I kept tripping on was making the butt joint alone the seam of the cylinder as I figured it would not hold. This time I did a pull test after gluing a couple of scrap pieces and was surprised to find the neoprene ripped before the joint failed.

Here is the contact adhesive I used and recommend: http://www.amazon.com/dp/B002DZRFIK/...140_TE_3p_dp_1

Carl