Columbia 1937 board tracker real gas tank

I normally don't build on ~$150 wally world type bikes but this caught my eye.
http://www.walmart.com/ip/39801995?...7321352&wl4=&wl5=pla&wl6=105949407872&veh=sem

The 'tank' is two pieces of pressed formed sheet metal that butt together in the middle via 2 struts attached to the frame via cut outs, two screws on each side plate, and top mounting hole to strut between the split top bar.

I thought I'd see if I can make it wide enough to get a filler and petcock on it and seal it up like Sportsman does.

I made new inner struts to widen the front 7cm wider and the rear 3.5cm wider.
NOTE: flattening the front struts V mount out straight gives you the back strut.

That leaves me enough room for the petcock, and with the wider front enough room for the filler I hacked off an old kit tank.

I found a spiffy thinner steel filler and venting cap that that is pretty darn cool.
If the bike falls over all you get is a little drip from the tiny vent hole as the cap is threaded with an O ring seal.
http://www.ebay.com/itm/Custom-Fuel...h-weld-in-Bung-SMALL-CUSTOM-NEW-/191495380281


For the petcock I'm going with the new MB kit one with the threaded collar so you can orient the valve lever and it has a double long inner screen with a Normal and Reserve setting.
http://www.gasbike.net/gasoline-tank-switch-for-2.5-L-gas-tank.html

Reserve on this flat tank should be enough for 10 miles or more.

I got some poster board to cut out the templates for the sheet metal and thinking I'll just pop-rivet it on because I found this to seal up the tank.
http://www.caswellplating.com/restoration-aids/epoxy-gas-tank-sealer.html

A gas-proof liquid 2 part epoxy that creates a solid tank inside the shell.

Under $100 to NOT use a peanut tank is worth it, and the bike itself has potential for handlebars down board tracker feel or sit up nice beach cruiser.
Worth exploring for me ;-}

 

[butre]

the steel is likely 18 gauge or worse and it's just simply easier to solder the gaps in that case. chances are he wanted to burn as little paint as possible as well.

 

[KCvale]

the steel is likely 18 gauge or worse and it's just simply easier to solder the gaps in that case. chances are he wanted to burn as little paint as possible as well.

Exactly correct.
It just needed enough weld spots to make it a solid structure, not air tight.
In fact, I think rivets and thinner gauge metal would work just fine other than attaching the petcock tube and filler tube.

I just taped up the seams and holes and let the tank sealer do it's thing, and it's thing it did very well.
It's a dead solid one piece air tight structure now AND it retained it's paint and stickers.

Just some cosmetic work and mounting and that's a done bike, with the exception of maybe a Poo-Poo type pipe after it's broke in.

Just a WARNING about that caswell tank sealer...
Don't trifle with this stuff. Once mixed it shows no mercy to anything it touches.
It attaches to everything and there is no way to get it off, it impervious to most every chemical there is that wouldn't eat the work before it softened it, and it dries solid.

 

[james65]

That being said, it sounds like caswells will be my choice over kreem brand in the future!

Great thread

exactly correct.
It just needed enough weld spots to make it a solid structure, not air tight.
In fact, i think rivets and thinner gauge metal would work just fine other than attaching the petcock tube and filler tube.

I just taped up the seams and holes and let the tank sealer do it's thing, and it's thing it did very well.
It's a dead solid one piece air tight structure now and it retained it's paint and stickers.

just some cosmetic work and mounting and that's a done bike, with the exception of maybe a poo-poo type pipe after it's broke in.

Just a warning about that caswell tank sealer...
Don't trifle with this stuff. Once mixed it shows no mercy to anything it touches.
It attaches to everything and there is no way to get it off, it impervious to most every chemical there is that wouldn't eat the work before it softened it, and it dries solid.

 

[KCvale]

That being said, it sounds like caswells will be my choice over kreem brand in the future!

Great thread

The package hype says you just pour it into a previously Kreemed tank or even rusty tank and it will seal it, it sealed what I made is all I can say other than heed the handling precautions.

Unfriendly painting conditions today but I did a fluid test.

It holds ~6 Liters, ~1.6 Gallons, or triple the size of a typical 2L MB gas tank.
That should give it a conservative range of 150 ACTUAL miles (not the marketing hype) even running it hard.

I let it drain completely with the petcock in the On position to measure how much was left in Reserve but there wasn't any, bum petcock? or just not enough room and height in the tank to make a difference?

My Q-tip petcock tube fiasco ended up sealing the whole inner tube so I drilled it out today and it was pretty long hole to open cavity, too long for the secondary straw in the petcock to make a difference.

Certainly no biggie, top off the tank with an even gallon mix every ~150 miles or so and you're good to go with room in the tank ;-}

 

[Arty]

I think it turned out great.

 

[fattirejack]

Looking good, I've used Caswell before. It will fill some big holes, sealed 3/8 petcock bung on one of my sportster tanks, had to drill it out.

 

[KCvale]

Done

Done.

I'm happy with the build but not thrilled with paying over twice what I paid for the whole bike to make the tank.
That's OK, I learned gas tanks and know what to and what NOT to do on the next one ;-}

 

[fattirejack]

Your tank looks great, how about sharing the "what to and what not to do" with us.
Thanks

 

[PocketBiker]

KC Masterpiece!!

Looks like the "Kreem" of the KC Masterpieces! Man, that is so sweet! Yes, you spent a lot, but..... look what you got. I sure admire your quest for quality! That's one spoiled China Girl!

One always has to spend more than expected on the prototype. I would be fascinated to know, what changes you would make on the next one... No doubt, you might make a few changes on the tank procedure?

Congratulations on a beautiful bike!!!!!

Jim

 

[KCvale]

Thanks guys, I was having my doubts but I'm happy with the outcome ;-}

Considering how remarkable that caswell stuff is, the center does not need be made from welded heavy gauge steel.

I think chain guard gauge sheet metal formed to fit inside with a set of struts with screw holes to match the side covers holes.

Picture a box open at each end with a couple of struts for new end caps to attach to them like slip on lids.
Then mount the filler and petcock bungs to that.

Without sides you could use bolt on type bungs and secure them from the inside.
Then just trim the right cover were it hits the bungs, then screw both side covers on over the center structure.
Throw some pop rivets around the seams, tape them off, and let the caswell do it's thing.

The object it to not have to weld anything.
Lighter, cheaper, and no damage to the bikes covers.

A clever guy with time and a sheet metal shop could make the ready-to-go center structure with filler, petcock and mounts to sell to anyone that has the stock bike.
It's the end users job to paint it, install his side caps, and seal it up good.

That also means the end user can paint the tank and side covers anyway he wants.

It would still be a long project, but with a base you wouldn't need many tools or welding equipment.

Just a thought for someone with the resources, and if you make one I'll buy the first one.
Then again, since I just devised this as I tried to answer the questions, I may just see what one of my local sheet metal shops can some up for cheap and beat you to it ;-}

Build on guys, my next project has already started and it doesn't involve gas tanks.
(Spoiler) 10G long shaft shifting build.