How to fuelproof properly
 

Hi all,

I'm an experienced glider and electric pilot and am now building my first glow model. I seem to be having some trouble with fuelproofing. The model is a Herr Cloud Ranger and I've got a Norvel .074 mounted on it. After running it for a tank or two... the covering around the fuse just aft of the firewall and on the cowl cheeks is starting to bubble very badly. I'm positive it's due to the fuel.

I glassed the firewall and inside of the cowl cheeks to add strength as well a fuelproofing. However... I just don't see a way to keep the covering from getting fuel behind it. Is there something I'm missing or is this typical?

Any help would be appreciated.

Eric

How to fuelproof properly
 

Eric:

It's probably too late now, but on the next one flow CA along the edges of the covering before you trim it at the firewall. Since I've been doing this I've never had the film separate from the wood. I'll do this at all places where the covering ends on wood. The overlap in the wing saddle, for instance. Where the covering laps over covering I've never had a problem.

HTH

Bill.

How to fuelproof properly
 

Bill,

Thanks for the info. I have uncovered the blistered areas and was waiting for a tip like yours before I recovered it. Should I also be fuelproofing the inside of the fuse around the tank?

Thanks,
E

How to fuelproof properly
 

Eric:

Any place fuel is likely to wet should be fuelproofed. With the tank shoved up inside the nose, fuelproofing the tank area is difficult. My somewhat effective method is using a spraycan of fuel proof paint and fogging the inside. Doesn't get everything, but it's better than nothing. Theoretically, the entire inside of the plane should be treated, but worst case is usually a burst tank, when that happens the engine quits and you land. The fuel seldom gets further than the radio area anyway, often doesn't get that far. So, if you seal the tank area and the floor of the radio box, maybe a bit up the sides of the radio area, you have all you need. You can overdo it - the paint or epoxy adds weight.

Hope this helps.

Bill.

How to fuelproof properly
 

William, Eric,

I have suggeted this before-some said it wouldn't work, but I've done it for 15 years, and NO PROBLEM.
Get the least expensive thin CA you can, (sometimes you can get a yellowing bottle cheap from your LHS) and squeeze it in the tank/firewall area. Fuel proof up to about 20% nitro, and you can get it everywhere.
KEEP YOUR FACE AWAY FROM IT WHILE YOU ARE DOING THIS!
It will fuel proof EVERY nook and cranny.

Jetts