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Jim2
05-25-2011, 10:29 PM
I bought a discount fuel bottle off the internet last year that came with a child-proof plastic cap. My intent was to put some gas in it to carry on my motorcycle because the tank is so small on that bike. Anyway, the first time I filled it with gas, and took it out on a ride, it leaked! It stunk up my saddlebags, and I was pretty disgusted with the whole thing. So, the bottle and cap has been sitting on a shelf since last year.

Now, it's riding season again, and I'm wondering if I could make a replacement cap. The bottle is aluminum. Would it be safe to make a replacement cap out of aluminum, brass, etc.? What metal would be best?

thanks,

Jim

Evan
05-25-2011, 10:32 PM
Buy a SIG fuel bottle. End of problem.

Lew Hartswick
05-25-2011, 10:34 PM
I wouldn't use aluminum for sure. It'll gall and that is the end. :-(
Brass may work BUT what about Delrin that should seal and not
cause thread problems. ???
...lew...

Jim2
05-25-2011, 10:40 PM
Evan:

Cheeses, you make your own mill, and I can't make a replacement cap for a fuel bottle! ;-)


Lew:

I'm not sure about plastic at all. I've never worked with it on the lathe for one thing. The other issue is that whatever the OEM chose didn't work *at all*. Last summer when I first noticed the problem it almost seemed like the cap had been melted by the gasoline. When I pulled the bottle down off the shelf this year, the cap can be removed from the bottle without turning the cap. It has shrunk enough that the threads on the cap no longer engage the threads on the bottle!

Would delrin work with gasoline? I just don't know.

Jim

darryl
05-25-2011, 11:49 PM
Check out the Cole Parmer chemical resistance database. You enter the two parameters, a material and a compound (like fuel of some kind) and it gives you the compatibility rating.

Evan
05-25-2011, 11:54 PM
Delrin is completely resistant to petroleum products.


Cheeses, you make your own mill, and I can't make a replacement cap for a fuel bottle! ;-)



You assume that the fuel bottle is worth making a cap for. What will it do under pressure full of fuel on a hot day?

I have carried SIG fuel bottles filled with white gas in my camping gear for decades on deep wilderness canoe expeditions and have never had a leak.

Evan
05-26-2011, 12:09 AM
I just uploaded an extremely comprehensive properties and chemical resistance chart for many plastics from my library to my server.

http://ixian.ca/pics8/Chemical_Resistance_Chart.htm

A.K. Boomer
05-26-2011, 06:04 AM
Its most likely not the cap or the bottle but the fit of the two together or a cheap seal their using - take some time to analyze the reason as to "why" and you might not have to make anything - just modify...

winchman
05-26-2011, 07:51 AM
Isn't it illegal to dispense, store, and transport gasoline in any container not specifically authorized and marked for that purpose?

ikdor
05-26-2011, 07:57 AM
Isn't it illegal to dispense, store, and transport gasoline in any container not specifically authorized and marked for that purpose?

Only if you live in the land of the free ;)

Igor

Evan
05-26-2011, 07:58 AM
Not if it is less than a certain quantity per container. That is why it is legal to store and sell propane in 1 lb bottles. Funny thing about that is a store may have a hundred lbs of propane sitting on the shelves along side 50 gallons of kerosene beside 50 of gallons of white gas fuel all in the camping equipment section.

Incidentally, the SIG fuel bottles are available in anodized RED.

Hopefuldave
05-26-2011, 08:57 AM
I just took a look at a "vintage" steel fuel can (2 gallon), it has a bronze cap with a cork seal - bronze is "non-sparking", cork's unaffected by petroleum solvents, so maybe they had it right 50+ years ago? It's still tight enough that it gave a good "pop" from vapour pressure when I opened it after at least 5 years, too!

Just my ha'pennorth,
Dave H.

Jim2
05-26-2011, 09:33 AM
Sounds like it's time for me to buy some delrin!

The seal on this cap isn't all that complicated. The cap threads into the bottle, which is one of these one-piece, extruded(?) jobbies. You know like the water bottles they make now--only this one was for fuel. There is an o-ring that seals the cap against the top of the bottle.

thanks all,

Jim

derekm
05-26-2011, 03:17 PM
Delrin is completely resistant to petroleum products.



You assume that the fuel bottle is worth making a cap for. What will it do under pressure full of fuel on a hot day?

I have carried SIG fuel bottles filled with white gas in my camping gear for decades on deep wilderness canoe expeditions and have never had a leak.
yep I can believe that but some of the gasket/o-rings they put on dont seem to like methylated spirits. (2 x primus 96, svea 123, 2 x tilley lamp :) )

derekm
05-26-2011, 03:27 PM
Only if you live in the land of the free ;)

Igor

in this country all the fuel cans must be "made in germany" :)

ikdor
05-26-2011, 04:26 PM
in this country all the fuel cans must be "made in germany" :)

Well, that's only fair. It's not called a jerrycan for nothing :D

Igor

rohart
05-26-2011, 07:20 PM
Evan - That's a very useful (looking) chartr, but I can't work out the key.

I mean, what do the entries G, NR, LR mean ?

I could hazard a guess at Good, No reactance, Low reactance, but that would be a stab in the dark.

Evan
05-26-2011, 07:34 PM
G= good, LR= low resistance, NR = not recommended.