Rendegade

Hey all, I'm just about to start knocking together a shark, and i've got a 25fp to go into it. Now I notice that everyone's running muffler pressure with these, but I take it you're not still using the uniflow tanks anymore, so what gives?

Is it a simple clunk tank or what?

Jim Thomerson

Uniflow with muffler pressure is the way to go. Some guys fix the tank like an RC tank with the uniflow and pickup lines connected and flexible. I run metal tanks with fixed uniflow: open air, muffler pressure, or crankcase pressure.

downunder

Plastic clunk tanks set up as Uniflow are the way to go. I set mine up with a solid (copper tube is best) Uniflow line bent so it goes from the stopper to the outside wall of the tank then runs along the centre of the wall almost to the clunk feed line. That just makes sure the clunk line doesn't get obstructed by the Uniflow line. Usually the tubing used for the Uniflow line will have a slight bend in it (from being coiled up) so use that bend to help point the clunk at the centre of the outside wall when you hold the tank on its side (simulates what happens in flight). Fit the tank to the model so the back end of the tank is further outboard than the front to use the last drop of fuel (that accounts for the natural yaw of the model in flight).

Set up like this you can experiment with using muffler pressure or not or by blanking the Uniflow line and venting the other (with or without muffler pressure) you can find the set up that works best for you. Chances are the best will be Uniflow with muffler pressure although right now my latest model is Uniflow with no pressure, mainly because the engine/muffler combination I'm using didn't have any provision for muffler pressure so I gave it a try as is and have been perfectly happy with it. It works in Adelaide, not sure about Perth though .

Rendegade

Yeah, things are bit weirder here than in adelaide. Over here the sun sets over the ocean, how weird is that?!

Thanks for the info, I'd had in mind that a uniflow clunk would have to really have two clunks tied together (I think Al Rabe messed with that didn't he?) or it'd pretty muchly be an RC tank turned on it's side.

All I have do no now is build the goddam thing!