ClarkFlyer

Hey, Folks....I'm assembling a Speedy Bee Arf.....actually it is done. I did everything by the book and decided to test run it and make sure the engine was plumbed ok. Well, while I didnt time it, I'm guessing I got about a 4 minute run. Looking closer, I see the tank is wayyyyy too little. The ARF calls for up to a .28 size engine. They provide a rectangular 85CC ( little less than 3 oz) tank. The manuel for my OS .25 FX calls for a 6 oz tank or about 200 cc. In this plane, the tank mounts as normal inside the firewall with the rear 1/2 going into the wing/fuse assembly. The only way that I can see to install a 6 oz tank would be to put it inside the wing/fuse. This would put the tank about 3 inches back from the needle valve. In addition , I'll need a few extra inches of fuel line so that I can attach/detach it every time I fly. Is this going to work? Any other ideas?

MinnFlyer

My Feedback: (4)

That should be fine

Salty25

My Feedback: (9)

I have this ARF waiting to be built. I opened the box but did not pay attention to the tank included.

I plan on using a 30FS for power. Post pics of how you finally mount your tank and how it works. I'll have to do that mod soon it seems.

ClarkFlyer

Salty, I did the modification and it works fine. I can't post pics but I'll describe it. Keep this post and refer to it when you're ready. The stock tank mounts in the fuse right behind the firewall...like most planes. The rear half of the tank extends into the wing/fuse assembly. The problem is that a 6 oz tank is too big for the openings, both in the fuse and the wing. If you enlarge the whole large enough for the tank, you'll lose all the strength. I cut the covering on the bottom of the wing so as to access the area where the tank would go. You have to cut away some formers and braces. The tank mounts so that the nipples on the tank are about even with the opening in the wing. I then drilled holes in the top fuse area behind the firewall. Leave the fuel lines a bit long. So...putting the wing on, you attach the aileron wire and then you run your two lines up through those holes and out the top of the fuse to the carb and the muffler. I hope this makes sense when youre holding the parts and looking at it......sorry, can't post pics. feel free to ask questions when you get to this step.

Salty25

My Feedback: (9)

Have you flown the plane with this mod yet? Was wondering about any fuel draw issues with the long lines. If you put the tank on the CG line there shouldn't be any problem there.

I can picture the mounting of the tank from the bottom of the wing. But, what did you use to keep it up there?

Which tank did you put in?

ClarkFlyer

I haven't flown it yet but bench tested it. I held the plane at various attitudes and it seemed to run fine. I happened to have an old 180cc rectangular tank from a previous plane. I removed enough of the formers to allow the tank to sit where I wanted. I put a piece of foam in, then the tank. I then laid another piece of foam on the tank. I cut a piece of thin plywood and glued it in to hold the tank rigid. I didn't worry about cutting the formers as I think the tank probably adds quite of bit to strength to that area. Given the way it ran on the bench, I'm not anticipating any problems in the air.

DVI

How about using the tank mounted in it now, and put a 4 to 6 oz tank behind it plumbed togeather. The forward tank would be the header tank.
I have used a header tank years back, now I just install a fuel pump.

ClarkFlyer

Thats a good idea but I don't think there would be room. I used a 180 cc tank, which is a bit less that than 6 oz. You could probably could use a tank maybe as big as 8 oz...maybe...Its important that the tank be not too big in the width/height measurememnts. I used this 180 cc tank with the .25 before and was happy with the flight times.

Salty25

My Feedback: (9)

With a header tank can't you have the larger tank lower? I've never used one before but have seen them on heli's.

If I remember right they have the smaller tank mounted higher then the larger one. Would that cause a fuel draw problem?

I'm not sure if you could even do that on the Speedy Bee. The tank in its normal position sits with the fule tubes sticking out of the firewall, no room to run the extra lines to the lower/other tank.

BillS

I have used a number of header tanks and they work well. It is probably best to keep both tanks close to horizontal.

Bill