Gas caddy

[cbrxx]

I want to make an aluminum gas caddy for a motorcycle dealership.The only ones I could find are only 30 gallons. So I want a bigger one about 2x2x4 feet. What thickness aluminum should I use and what kind of supports should I put inside it? I was thinking 1/4" thick and a cross brace inside the tank to keep it from bowing out or getting dented in.

[Rocky D]

It sounds interesting...I've never seen one...what is it's function?? Can you show us a picture of one?

[david_r]

Rocky,
Sounds like a gas tank on wheels to me.
If it was me, I'd go to the truck wrecker, get an aluminum saddle tank and make a cart for it.
Only problem is mounting a neck for the pump to screw into. I used one that was in the side of a 55 gallon drum. It had a near perfect curve in it. Rivets and Hylomar turned out to not be enough to seal it. Too bad they painted it before testing for leaks.

If this is going to be transported on the road for refills, you may want to check with DOT for max size. I think your 120 gallon tank may be over the limit.

If you are set on making your own, do include baffles. You can just notch opposite corners but should install drain plugs between each one if you go that route.

[Ken M.]

2x2x4 is about 120 gallons. Is it going to be 4 feet high or 4 feet wide? It makes a difference. Remember the pressure is a function of the depth. The specific gravity of gas is about S=.69. Thus, the specific weight of gas is .69 X the specific weight of water 62.4 lbs/ft^3. So the specific weight of gas is .69 X 62.4 = 43.1 lb/ft^3. 16 cf will hold about 690 lbs of gasoline. If it is 4 feet deep, the pressure at the bottom will be 43.1lb/ft^3 X 4 ft = 172.2 psf = 1.196 psi. For 2 feet deep it will only be about 0.6 psi.

One way you can get away with less material than the other. You also need to decide how much deflection you are willing to accept. With out going through a lot of calculations 1/4 inch material should be more than enough. You can also take some small angle and weld it to the inside in the vertical to act as as stiffeners which will keep the tank from buldging.

[Sberry]

I second getting a truck tank good idea and cheap too compared to building.

[Rocky D]

I'd recommend using baffles rather than angles inside...more support. and to keep the gas from sloshing around.

[LeonS]

I agree the semi fuel tank would be the simplist of all, and there some pretty large size tanks out there. Ofcourse flushing the tank of residule diesel will be in order and that could take some time and not sure how good a job one could manage due to possible impregnation of the Al. Either way vapor venting is also a concern since the Al will heat up faster than black iron. With baffling necessary for this size tank, venting between the baffles is something to look at. Back in the early '80s my Bud, who owns a fab.shop, one of his vendors and myself had Suburans, got the bright idea to fab up side tanks. I wanted to use black metal but the salesman wanted Al., since we were building 6 tanks I lost out.
The problem was the heat expanding the gasoline and out vent pipe between the baffles would push the gas out the fill neck in to the wheel. The only remedy was to NOT fill the tank to their 24 gal. capacity. Dang, didn't mean to run on so, sorry about that.
One other thing though, while in the Military, A.F., loading recip.air craft, as a rule of thumb we used 6#/gal-summer, 7#/gal.-winter. So I assume you will be towing this w/an ATV.
Good day to all
L*S

[Sberry]

There would be no problem cleaning diesel out of it.

[cbrxx]

You can see a picture of it here http://www.handyindustries.com/gc.asp . Its a gas tank on wheels. After new bikes are sold they need a full tank of gas, so you roll the caddy over to the bike and use a hand crank pump to fill the bike. It will be 2' wide and 4' tall. I've never seen baffles before, should they run the full length of the tank or half way, and how many will I need?

[Rocky D]

Baffles can be made in different ways, they basically are a plate with a big hole or two in it, welded all around inside making sections, or cells and they stiffen up the wall at the same time. Hard to explain without a picture

Anybody else want to explain what a baffle is??

[cbrxx]

So if i was to make a baffle I would need another 4' sheet of aluminum inside, splitting the tank into 2 tanks, with some holes.

[Old Man Stick]

Anybody else want to explain what a baffle is??

LOL I 'll try

Baffle is a brake wall of sorts. Each baffle should go from top to bottom (Or close to) of a tank with pass holes cut in them to let fluid pass thorough. This helps keep sloshing down. There used in bigger hydo tanks to keep the oil form a worlpool affect. In your gas caddy here thay are saying a baffle to go from top to bottom not only to help keep the gas form sloshing but it would help suport your tank.



OMS

[Zrexxer]

Its a gas tank on wheels. After new bikes are sold they need a full tank of gas, so you roll the caddy over to the bike and use a hand crank pump to fill the bike.

Maybe I'm missing something obvious, but why do you have to roll the gasoline to the bikes? Bikes have wheels of their own. Wouldn't it make more sense to install an stationary aboveground storage tank on a stand and just roll the bikes up to it?

[cbrxx]

That would be great, but its not permitted by the town and if it was the tank would have to be outside. So I need something on wheels. Most of the time the bikes will be rolled to the caddy, but with big atv's and side by sides its eaiser to move the caddy.

[Rocky D]

I was thinking of the baffles going not top to bottom , but side to side to support the sides, They could be one or two 2 x 2 squares with the corners snipes for pass through. I see now how you use it....the vehicles are so close together, it is easier to run the caddy by and fill 'em up...makes sense when you could have a row of 50 of 'em to do.