seagull369

Anyone have experience gluing (glueing?) up a crack or 2 on their plastic nitro tanks? I have 1 small hairline crack (on a flat section) on mine and am curious what might work the best.

I was leaning towards using some epoxy meant for plastic, embed some fiberglass cloth in it and use some wax paper to spread it out. Prep would be to sand and clean with acetone.

To answer those that are wondering,,, yes I'm too cheap to buy one [:-]

dustin7837

My Feedback: (1)

Clean it really well, then just go down to your local automotive store and find an epoxy that is gasoline / alcohol resistant. yes I know that the fuel is actually nitro methane with oil, but any hydrocarbon resistant epoxy will do. There are tons to chose from, but the most important thing is to get the tank clean around the crack.

Another alternative is to clean all of the fuel out of the tank and use a low power soldering iron to melt the crack closed.

ImpalaPolicePack

quality epoxy will cost as much as a new tank... i wouldnt bother with it and id just buy a new tank.

SyCo_VeNoM

+1

seagull369

Thanks for the replies. I'll give the epoxy a shot (have a bunch of it anyways). The only hobby shop near me charges a fortune for parts (way above list) and I don't feel like paying shipping costs for just 1 item online. I'll report back on how it goes.

DaveG55

Do the soldering iron fix. The plastic of the fuel tanks will not bond to any glue that I have found.

SyCo_VeNoM

http://cgi.ebay.com/NEW-HPI-Savage-X...item45f8254724 $11 SHIPPED $1 cheaper than tower, and most hobby shops.

ZeroKelvin

I've fixed cracks by cleaning the area very well, then putting a thin layer of JBweld over it. JB weld epoxy is cheap and it holds up just fine to the fuel. It works perfectly.

Bluethunder3320

JB weld didnt work for me. it came right off in a solid piece.

if that was me... id say f**k it... and pull out the butane torch....

The_Shark

maybe in the future, ive seen RTV black silicone sealent seal tanks (my t-maxx's tank primer hole has that stuff in it from 1999)

ZeroKelvin

One thing I should have mentioned(didn't think about it when I first posted) is that I lightly sanded the surface around the crack prior to applying the JB weld. By roughing it up, the epoxy was able to bond to very well. Mine has been on since 2 summers ago and still holding.

1QwkSport2.5r

I was gonna say - to get a good bond you need to abrade the surface so the adhesive has something to "grab" onto. The only other thing I was going to mention is Nitro fuel will eventually break down the JB Weld. I tried "stuffing" an old crankshaft I had sitting around. Someone said JB Weld + nitro fuel = mush. I soaked the crank in fuel for 3 days and it came out in soft chunks. (The JB was fully hardened/cured) I'm sure it will hold for awhile, but it eventually will need to be fixed again or replaced.

On a slight side-note to the OP: How exactly did the tank crack in the first place, and where?

The_Shark

rtv silicone doesnt seem to dessolve, and it always stays elasticy and wont break off.

rc awesome

Install a new tank, its not too hard

Ybenjulkay2x

better be , rather getting a new engine, it will mest up your engine due to not enough gas (lean) coz of unpressure tank due to leak..

seagull369

I bought it second hand and it was that way when I got it (of course the guy didn't tell me that). Found out the hard way when I filled 'er up. Considering I only paid 75 for it, I'm not complaining! One of the tabs the tank clips is broken too.

I noticed some silicone spread over the crack, applied from previous owner I guess, but it didn't hold. I pealed it off with just a fingernail.

In my experience, JB works adheres much better to metal than plastic. I also have some PVC cleaner & cement (more meant to solvent join plumbing fittings to each other) I think I'll play with on some scrap t-maxx tanks I've held on to to see if that works.

In case anyone's interested in this kind of stuff, I found an interesting adhesive online designed to work on polyethylene-type plastic (which I don't think the savage's tank is made of), which ordinarily is very difficult to repair outside of welding processes. Here's a youtube vid (this company actually has a lot of vids there showing how to work with with lots of different resins): http://www.youtube.com/watch?v=h-9yhanz5DE

ZeroKelvin

For that price I wouldn't complain either. Just clean up the cracked area very well with rubbing alcohol, hit it with some sand paper, and give it a good coating of whatever you decide to go wtih. For me, JB weld is on it's 2nd year and holding fine, but I'm sure there are plenty of good sealers out there. Someone mentioned RTV sealant, and I imagine that would be fine.I use RTV sealant on my carbuerators and engine backplates to seal them from air leaks and it has worked fine for me over the decades, damn am I that old . Good luck

Bluethunder3320

I would not go and buy silicone just to seal the tank.

Ive been cheap in my r/c history... Lol... Once i tried making better teeth on bevel gears with j-b.

It never worked, and i eventually spent $5 on new gears.

The one way i can ever see a crack in plastic sealing is if the two pieeces are actually melted together.