TOPIC:

wrote:

Flush your tank with denatured Etylalcohol or Bio Ethanol to prevent flash rust.






 

A good idea if going for a tank liner but,like I said, plating wont work as the surface of the anode needs to be bigger(or equal) to that being plated. No problem if you can cut your tank in half.Easily platable then but you got to find someone to weld it back together,which would burn off some of the plating,leaving it prone to rusting again and defeating the purpose.

A long time ago i had read an artikel about rust protection of fuel tanks. I don´t know for sure if it´s true but you can lead or tin plating the inside of the tank. You have to fill grains of lead or small lead balls and have to shake and roll the fuel tank in all directions for hours. A small layer of rubed off lead adheres to the surface as rust protection.

Sounds interesting. Any other details?

Phosphoric Acid is the go for stopping rust dead,  POR15 has a product that uses Phosphoric acid and Zinc oxide ?   The acid stops and converts the rust and the zinc put a thin layer over it stopping further rust. Phosphoric acid is the main ingredient in most rust converters, mixed with water at about 15 to 20 to 1...

Ok. Thats something to think about.I might end up going the tank liner route in the end,though It will be the last resort. Ive been busy with another possible solution. I thought id have a go at making a new tank from Carbon Fiber!!!
 No idea if its going to work but I don,t see why not. If it does work, no more rust in the fuel system. Eva Eva!
If not,I'm sure it'll be a mess.
 I found an epoxy resin that is meant to be fuel resistant, heat resistant and with a high abrasion resistance,so that sounds like the stuff to use. The problem is that it mentions the heat resistance on the spec sheet,but I cant find anything about fuel resistance. I've emailed the company and I'm waiting for a reply.
 In the meantime,Ive been busy making a fiberglass mold of the tank and figuring out all the details Ill need to sort.
 
 
 
 
 



Its not as straight forward as it might seem. It is quite an awkward shape and there's all the hardware to think about. The rear mount the front mounts,the fuel tap and the filler cap.
 
 
 
 

For the rear mount,I riveted a strip of 8mm alu onto a 2mm plate to spread the stress.I made a recess for it all in the mold but it will be fitted at the end when everything is together. 

 For the fuel tap, I drilled out another piece of 8mm (maybe 10mm) tapped the holes and routed it to fit nice and snug in the mold.
 
 
 
 
 

 I'm still working on the fuel cap recess. Not figured it out quite yet. I've prepared the mold to accept the front tank to frame mounts but they wont be fitted until the bottom of the tank is cast.
 The idea is to cast in two pieces the pretty much glue them together. Easy peasy.What could possibly go wrong?!

Cool idea. If the resin you use isn't fuel-resistant you could probably line the new tank - Iooks like Caswell might make their kit in clear, if you're going for translucent (?)

Davido I love your "outside the box" problem solving throughout your project, I assume a "non-OE" composite fuel tank is legal for road use in your part of the world (or are you working on the "once it's painted who's gonna know" theory) 

wrote:

I thought id have a go at making a new tank from Carbon Fiber!!!
 .... What could possibly go wrong?!

I wonder if using an internal bladder would make some things easier? Essentially making a fuel cell for a motorcycle. I don't actually know what the inside of a fuel cell looks like, but I think they use bladders.

fuelsafe.com/fuel-cell-facts

If you could find someone to make you a bladder, that would minimize the worry about fuel compatibility as well as bonding strength of the two halves. And you already intend to assemble it from halves, so you can pop the bladder in place before assembly.

Of course I'm not sure how you'd get the fuel out...

A guy over at ZRXOA made a carbon fiber tank. Carefully reading that thread may help you avoid some of the pitfalls he encountered.

The thread is titled, Carbon Fuel Tank Build. The user name is Peter.

wrote:

A guy over at ZRXOA made a carbon fiber tank. Carefully reading that thread may help you avoid some of the pitfalls he encountered.

The thread is titled, Carbon Fuel Tank Build. The user name is Peter.
 

 A 'BIG' thanks for that, TexasKZ. A great link to a fantastic thread. Exactly what I needed.
Like I said earlier,I was waiting on a reply from the company that makes the resin I was recommended.(Smooth-on). They replied today saying that the product is NOT fuel resistant,they would not advise using it and they don't produce anything else that might work!!
I'm almost at the stage where my molds are finished, just some final sanding and cleaning up, then they're ready to go. So that was quite a blow,to be honest .I'm now questioning everything I've been told by my supplier.
 Then I saw this post and sat down to read Peters thread.Lots of info and ideas.Even more,the fact that someone else has actually done this has given me a boost.I'm going to try and get in touch with this guy. I have lots of questions.

When you finish the tank then its only a short sprint to full carbon, i can imagine how cool it will look, flicked through that guys thread, talented man.
 

Not interested in the look. Never really liked it (and a mess if you don't get the weave sitting right).I was planning on a gel coat first to give a solid black finish. (Though the Rex does look great.) Im in it to be done with rust in the fuel system. No steel,no rust. 'Its the only way to be sure' (as Cpl Hicks once said.)