Jack_K

One of my favorite fuel tanks has a crack at the bottom of the neck (the part the "cork" goes in).

I roughed up the crack with a coarse file and dabbed some MEK over it. Let it set a few hours and it seems to be just fine now. I pulled and pushed on the neck and the repair held. I put the fueling assembly back in and tightened the screw. It still held up.

Will this repair hold up? Any other way to repair it?

Jack

Tom Nied

I'd buy a new tank.

Jack_K

Thanks. I'll send you my mailing address.

spaceworm

MEK is a solvent but not for polyethylene which is what most fuel tanks are made of. I don't know how the MEK did anything except clean the area it was applied to. However, once an area is cleaned I have had limited success with applying a generous amount of silicone rubber sealant over the cracked area, and letting it cure. But, like others said, I would buy a new tank, unless it is an emergency and a leak in the tank would not damage anything. Good luck.

Jack_K

What can I say? It seems to have worked. I read about roughing the surface and using MEK (somewhere) on the web, so I tried it. What can I lose, a little fuel? NBD

HighPlains

My Feedback: (1)

"I'll send you my mailing address" - classic!

When I was a poor kid, I fixed tanks with strips of plastic and a Weller soldering iron. They looked like hell, but worked fine. The strips were made from plastic bottles that looked the same type of plastic.

Gizmo-RCU

My Feedback: (27)

Why tempt faith when tanks are so cheap? I predict you will regret trying to fix the unfixable (never really works out) the seam is weak no doubt and may well fail again in another location. Like batteries once they start going bad there is no going back and the results are never good?

Jack_K

faith?

HighPlains

My Feedback: (1)

I did it because everything was mail order 46 years ago, so most orders took about two or three weeks. Never had one fail, and I repaired several. On top of that, I often modify the shape of tanks by heating them up and molding them against a buck as they cool off. That way, I can fit a larger tank than I otherwise could. It's called modeling, try it sometime.

RAPPTOR

My Feedback: (41)

hot glue

Jack_K

Hot glue won't stick very long.

Twin_Flyer

My Feedback: (4)

Either use the soldering iron trick or go to the LHS or Tower Hobbies and order a new tank.

If not then one day you will find you just filled the plane with fuel and not the tank!

Bill S.

speedracerntrixie

My Feedback: (29)

These days a new tank can be at your door in a few days. If your too cheap to buy one ask around the field, I'm sure one of your flying buddies have one that will work. And before you ask........no a broken prop can't be repaired.

Jack_K

i appreciate all your help, but I just wanted to see if I could repair it. I'm going to use it on my engine test stand (if that's OK with you).

Sure, a broken prop can be repaired, but I wouldn't recommend using it on a running engine.

bikerbc

Years ago in an emergency some cracked props could be repaired by wrapping string saturated in glue around the crack equal amounts on both sides to balance but now adays its hardly worth it . I Think it would be better to make a new tank ,or buy a new tank sooner than risk a fuel leak inside an airframe ,however if you are just using it for a bench test tank then great idea..you will get to see how well your repair stands up . I would be inclined to wrap a small gear clamp around the neck for extra support maybe . I bet somebody at your club will have a used one they would either give you or sell you for next to nothing . We all have a few kicking around . You know this forum can be friendly we don't need to argue or insult each other like kids .

raptureboy

shoe goo works on everything

Jack_K

What's shoe goo?

Never mind. I found it.
https://en.wikipedia.org/wiki/Shoe_Goo

jetmech05

I wouldn't use it.

raptureboy

Good as anything else suggested but still a new tank is a sure thing and all of a few bucks. There's frugal and then there is just plain old cheap.

Jack_K

Thanks for the encouragement. As I already stated, I wanted to see if it would work. Well, guess what? It's working great on my engine test stand. I don't need to buy another tank; I have about a dozen already. You can save your criticisms for someone else.

aspeed

I use a dented/crunched tank on my test stand too. It is always good to try stuff out. Good education to learn plastic welding in case there is a bigger project to do. I have a windsurfer that needs a repair where plastic welding may save a few hundred bucks.

jetmech05

Jack please remember you asked us our opinions. We gave them and it seems you didn't like the answers you got a became nasty.
The RC community is kinda small.

Jack_K

Well you're right, I was a little nasty. However, being called "plain old cheap" required a response in my opinion. I apologize to everyone except that poster.

Yes, I did ask for opinions. But I asked about repairing a tank, not whether or not I should buy a new one. I did get several pertinent responses though.

jetmech05

Jack thank you for your response. You aren't the first by a long shot asking how to repair a tank.

049flyer

My Feedback: (18)

New tanks of the right size and shape are NOT ALWAYS available. Not nearly as many tank options these days as in years ago. Tank manufacturers are going away or reducing choices in their product lines.

I fly smaller planes and sometimes a particular brand and shape of tank will fit much better than another. If that tank becomes damaged and is not available, then a repair may mean the differences between installing a 4 oz tank and a 2 oz tank.

How to repair a tank or construct a new one is valuable information for a modeler.