Anybody built a fiberglass/carbon fibre tank?

Airwolfie

Airwolfie

XS650 Guru
Messages
2,023
Reaction score
70
Points
48
Location
United Kingdom
I was wondering if anybody has done or attempted to build a fiberglass fuel tank?

My main concern is fuel proofing it, and also how to get the fuel cap and petcocks into the glass.

I am sure I am capable of making one, just if it lasts would be the worry!

I am thinking of making a male plug, get it sorted, and then make a three part mould to fab the tank.

Thoughts and suggestions are greatly appreciated!
 
Hi wolfie,
not gas tanks, no.
But one time I had a weekend and evening business building 15 foot fiberglass sailboats.
You'll need a temperature controlled building with really good ventilation.
Tyvek suits and a breathing mask.
Realizing that your first, and perhaps the second attempts will be a total screw-up.
Have several paid up orders in hand to help pay for the mold and set-up costs.
And a really understanding spouse.
Trust me, it ain't worth the effort.
Buying an aluminum and stainless capable TIG machine and taking a welding course would be a better thing to do.
 
Checking out the similar threads at the bottom of the forums page, looks like fiberglass may not work well. I've been molding, shaping and repairing ABS plastic and wondering if a tank could be made of ABS, I sure could mold and paint a nice one. After checking out ABS vs gasoline, not a good material either.

Scott
 
mrtwowheel said:
Checking out the similar threads at the bottom of the forums page, looks like fiberglass may not work well. I've been molding, shaping and repairing ABS plastic and wondering if a tank could be made of ABS, I sure could mold and paint a nice one. After checking out ABS vs gasoline, not a good material either.

Scott
Click to expand...
mrtwowheel,
I belive HDPE plastic, as well as PEX would be suitable for a fuel tank. However, these materials are not suitable for DIY or even small scale commercial production, as a mold would be required.
 
HDPE and Polypro are good but difficult to make look nice. They are is soft and easily scratched, and cannot be painted easily. But they are completely ethanol proof. Fiberglass is a problem these days with ethanol, but some have had ok results with sealers. I found that both epoxy and polyester resin is no good with ethanol. The biggest problem with all of the plastic materials is safety. Plastic and fiberglass will always rupture if impacted in an accident. That is why they are not DOT approved for motorcycle fuel tanks.
I am in the prosthetic and orthotic business and have access to a 5 axis CNC and all materials that could be used for plastic / fiberglass fabrication. I went through all of this with building my last café project and wound up having an alloy tank made.
 
Gibson said:
I am in the prosthetic and orthotic business and have access to a 5 axis CNC and all materials that could be used for plastic / fiberglass fabrication...
Click to expand...

Very interesting! Would you happen to know if those materials have a better tolerance to isobutanol, which is the ethanol substitute used in some 'ethanol free' fuels?
 
One option not discussed in this thread, is an actual steel, aluminium, or PEX/HDPE tank, covered by a fiberglass shell. This is not an uncommon route, even for some stock bikes. This would allow the actual tank to be quite crude/boxy, thus easy to fabricate. Welding HDPE using an extruder is fairly easy, but buying an extruder is very expensive. Then, after the builder is satisfied with the look of the fiberglass shell, it should be possible to fill the void between tank and shell with building foam or similar, so the "fake" tank feels solid. I guess one could use some kind of release agent inside the shell, to make it removable.
 
Twomany, LDPE is resistant to isobutyl alcohol. The epoxy chemical resistance table says NR (not recommended). Polyester I did not check but I'm relatively certain that the answer is no...It would be nice if there was a resin out there that is chemically resistant for lamination. A metal tank inside a glass shell is a good idea, and will be safer too.
 
Thanks for the replies guys! I guess I won't be going this route! It was just a thought anyway!

Interesting things have been said though!
 
I'm building one right now (For a motorized bicycle project)... and have done some tests with fiberglass/epoxy resin (MAX GRE Epoxy).

Here's the epoxy I'm using: http://www.ebay.com/itm/EPOXY-RESIN...429e8c9&pid=100005&rk=2&rkt=6&sd=310219838956

I just simply laid up some glass/resin and then poured regular gas (10% Ethanol) into it and let it sit for a few days. So far, it seems to be holding up. It's not breaking down nor getting soft. I'm still working on the tank's core (using insulation foam) so I haven't made up the tank yet...but I think the Epoxy is going to work.

As to actually making the tank, I've seen some vids that have been helpful.

I watched this guy's entire build (30+ videos)--there's a lot of video to cover since he's doing a lot to the bike, but throughout the build he works on the tank and his process is pretty cool and does a great job with showing how he built his tank... and I'm going to do the same for mine:

And then this one for adding hardware:

Good luck!
 
Great stuff! Fiberglass is great stuff to work with and makes a beautiful finished product. Its easy to fix and modify also. I've used West System epoxy products a lot for boat building. I would use a sealer inside though for sure.
 

Similar threads

SpookyWizard
Popping my XS650 cherry, the Journey so far.
2 3
Replies
43
Views
3K
nj1639
nj1639
MaxPete
The Big Sue resto-mod thread
2 3 4
Replies
72
Views
2K
MaxPete
MaxPete
M
Fiberglass Question
Replies
2
Views
988
Max Midnight
Max Midnight
Bewarethemoon
Your ‘Two Cents Worth’
Replies
4
Views
460
Bewarethemoon
Bewarethemoon
Mailman
Boyer Bransden Ignition installation on my XS2
2 3 4
Replies
70
Views
11K
JRay77
JRay77
Back
Top