Homemade Fuel Tank

Nice work! From what I can see it looks great.

Looks good, and is most certainly safer than the tanks on Pinto cars

What is the thickness of the brass sheet?

That's great! Is their an internal wedge for the pick-up tube? Have you leak-tested it yet? Once it passes a leak-test.. be sure to flush-out any flux on the inside using solvent. Ken Cook has a lot of experience with hard-tanks. Maybe he'll check-in with suggestions.

I built my first hard-tank(s) about a year ago.. and found it really enjoyable! I used .008" Tin-plate sheet and plumbed with 1/8" copper tube. The Tin sheet I found at "Lowes" home-center in the Hdwe. dept. and the copper tubing I got at the auto parts store; near where they sell the instrument gages.

My tanks are tiny.. These were built for the CEF Speed Contest.

NEW222 wrote:Hi all yet again.  I have a set of Pinto plans here and I have an itch to try to build something nice over the course of a long time.  So I started tonight with it by making the fuel tank.  It is brass sheet with 3/32 brass tubing as per the plans.  I am a bit worried, however at the weight, so I was just wondering if my time, money, and efforts were wasted, or do you feel I can safely use this tank.  Please do not laugh at it, as it does have a few cosmetic issues, and was made by hand with crude hand tools.   Anyways, here are a couple of pictures for your enjoyment.

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I am not sure for what use (i.e. CL or R/C plane or car) this tank is intended for, but I like it and most likely could not build the same...no tooling, limited manual ability, good only for scratching my forehead when seeing stuff like this, but cannot make one

I still find the party-baloon tanks the best at least in my R/C planes, as these adapt their shape to the fuselage interior easily, the foaming of fuel in vibration is prevented, and this is darn simple to make and replace...

Thank you all for the kind words. It is greatly appreciated.

@KariFS - Thickness is somewhere in the .004-.005 range.

Now, roddie. roddie. I don't know about you. You are a great wealth of knowledge and thanks for all the help you have given me lately. Anyways, now to answer your questions.
1. No, there is no internal wedge installed in the tank for the pick-up. I will have to look at it better to figure it out, disassemble the tank carefully, and make and install them.
2. As for the leak test, no, I did not perform it yet, as I was waiting to see if anyone noticed I forgot to put my wedged for pick up in.
3. Thanks for the recommendation of flushing out the fuel tank with solvents before use. I thought and wondered about the insides after assembly, and forgot to ask this in my original posts, so thank you again. What kind of solvents would you recommend. I have mineral spirits here at home, would that be ok?

I will try to remember to take a couple of pictures of the inside after I disassemble it and build it properly.

@balogh - It is for a 1/2a sized control line plane called the 'Pinto'.

Also, roddie.  I will agree with you, that your tanks are small, now that I re-read your post and put together the size by knowing your tubing is 1/8".  But they look very nice and solid.

What flux did you use?  If water soluble, then use water, 3-5 fill and empty, at least 1 through each tube.  Follow this with some alcohol (denatured) to absorb the water and "dry" the tank.

I have about 3 olive oil cans to cut up as material for tinplate. When recycling food cans, open one end, wash with soap and water, then open and unroll flat. Using a rolling pin on the metal with a towel underneath works surprisingly well. The paint must be stripped prior to soldering. Finger nail polish remover often takes it off quick, but sanding is another choice.

Phil

Great idea with the recycling tin food cans. I never thought of that. And believe me, i should have.

NEW222 wrote:

Now, roddie.. to answer your questions.
1. No, there is no internal wedge installed in the tank for the pick-up.  I will have to look at it better to figure it out, disassemble the tank carefully, and make and install them.
2. As for the leak test, no, I did not perform it yet, as I was waiting to see if anyone noticed I forgot to put my wedged for pick up in.
3. Thanks for the recommendation of flushing out the fuel tank with solvents before use.  I thought and wondered about the insides after assembly, and forgot to ask this in my original posts, so thank you again.  What kind of solvents would you recommend.  I have mineral spirits here at home, would that be ok?

I will try to remember to take a couple of pictures of the inside after I disassemble it and build it properly.

Are there any other notes on the plan concerning tank construction? I asked about the internal wedge.. because of the pickup-tube being centered on the outboard-wall.. and the illustration shows what appears to be an internal V-shaped panel inside. A conventional wedge-tank's shape directs fuel to the pickup in flight because the pickup is located inside the bottom of the "V".. allowing all the fuel to be used. The tank-design on your plan is one that I'm unfamiliar with.

Since you're going to disassemble it, I would highly recommend using Copper tubing rather than brass, to resist corrosion. Use the same size if you want to stick to what the plan recommends.. but I personally would step-up to 1/8" Copper. Use an awl to enlarge the tube-holes slightly smaller than the 1/8" tubing.. and this will create a "pocket" for solder to fill around, giving you much stronger joints. Also.. be sure to solder (tack) the pickup tube to the tank-wall near the back as well.

dimples for solder to pool when installing tubes.



Below pic shows how I tacked my pickup tube at the rear corner. Be sure to leave room between the rear end-cap and pickup tube for fuel to flow! (The angled tube is a uniflow vent which wouldn't apply to your tank design)



I leak-tested my tanks using an empty fuel-bulb. Cap-off all but one tube and connect the fuel-bulb to it. Submerge in a glass bowl (or jar) of water and squeeze the bulb to pressurize the tank. If you see any bubbles.. mark the location(s) and re-solder. Re-test until it doesn't leak.

I flushed-out my tanks afterward using a solution of baking soda and HOT water in the glass bowl. Connect the fuel-bulb to the tank with all caps removed and submerge it. Rinse by drawing the solution into the tank and out.. by squeezing the bulb and letting it fill.. then squirting the solution back out several times. Afterwards.. remove the tank and force out any remaining water. Follow-up with a rinse using lacquer thinner in the fuel-bulb.. BEING CAREFUL not to squirt yourself!   Use an empty jar or tin can.. with a rag over it to avoid this. Force all the thinner out of the tank.. and you'll be good to go.

How will the tank be mounted? Is it a lot bigger than the measurements on the plan? Building another one to the proper dimensions probably wouldn't take as much time as the first one; now that you have the technique down.

@roddie - No, sorry, there are no other notes on the plans of construction, or installation of the fuel tank.  Just what I had posted.  It does most definitely appear to be  wedge in the design.  I just could not picture it, then got to building and then forgot to add it.  Call it weird, but after looking at the complete plans, the pick-up, wedge or not, is on the inboard side of the airplane.  Weird if you ask me, the novice control line flyer.  As far as I thought, it should be at the outboard side, no?  As for the tubing, I could look into the copper tubing in 1/8", just thought since my other small stuff has used 3/32 copper, I would continue.  And the dimples, I really like that idea, as I soldered inside and out for security.  As for disassembly, it is.  I saved the tubes, and large sides, the rest was scrapped, as it did not want to disassemble properly, so I salvaged what I could.  And as for size wise, it was at absolute max allowable for the location.  I will have to get a new sheet hopefully next week and try this all over again, only better.  Also, I will draw it out on cardstock, and slightly smaller than the original so I have a bit of wiggle room.  It appears to fit tightly in its location.  If time permits, I may try to find some thin tin so I could get back on it sooner.  Thanks.

I have two things I didn't see mentioned. Roddie did mention brass tubes and corrosion. Brass will turn green and slough off, but it's not a problem with a little preventive maintenance. defuel it after use. And if you aren't using it every few days, flush the tank after and the tubes won't gook up in a few months. If it's been sitting unused for a long time, I blast it out with brake parts cleaner and that gets the green out. I filled an old ugly mystery tank with BP cleaner and shook it a few times and it works great on my Yak-9. Brass tube is the choice of most tank builders I've ever seen. It's harder than copper and still easy to solder.

Speaking of brass, Tin is a better choice for the tank shell, much lighter and I think somewhat easier to work with, more malleable. Besides, brass tubes or copper, you still need to flush your tank to prevent corrosion if not in regular use .

If this is a tether car then a wedge tank would be best. The pickup and wedge need to be on the same side as the outside of the circle, whichever way you run the car.

I think airplane thought is invading our car design. Remember it doesn't go up and down, so it seems to me the wedge should be at the bottom where gravity holds the fuel. Look at this picture I drew. Does this make more sense for a car. This example would be for a counter clockwise car, wedge points to the outboard side just like a plane. Y'all analyze my idea. I've never had a car or even seen one, so don't go all Rusty says... lol
Rusty




EDIT: Actually the overflow vent should b a "J" shape dropping in and turning back up to the top. Chamfer the end in case you get it too close to the wall while soldering.

Sorry, I guess I should have been more clear when I said Pinto. It is a control line 1/2a design, flapped stunter. I will attach a photo of the plans. This is in case it helps anyone with what I am trying to accomplish. The tank picture I had posted earlier is in the bottom left corner.

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Oh. Duh. Yeah,I've even heard of that plane

Thanks RknRusty for the advice especiallyfor that of flushing the tankout if not inuse for a while. I did nt think of storage. Also, where would one source out the tin you mentioned to build with? Is there a standard use for the stuff other than modeling? Thanks.

New222 , I think Hobby Lobby has the tin as also brass sheets , tubes ect. http://shop.hobbylobby.com/products/-008-tin-sheet-107342/ Eric

The Pinto is a scaled down version of the Oriental. The tank is a version of George Aldrich's "pinch corner" tank, although others probably also used it. There is no baffle inside, the end of the tank forms a wedge.

Brass tubing will corrode and sometimes get a hole or a crack inside the tank over time. Copper is much better for long-term use.

Holes for the tank have more surface area to solder if they are punched (sharpened nail) rather than drilled when using tin can stock.

If you have not soldered much, make sure you can tell if it is a cold-solder joint...and use a big iron or a torch.

Of course these are only opinions. Your tank, your choice.  

George

Hi New, It looks like we're getting this figured out! I mentioned in my 1st post, where I got my materials. Other options would be to check your local hobby/craft stores. Call and ask if they carry "K & S" metals. If so; there's a good chance they'll have what you need. Tower Hobbies carries the K & S line too..

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXUTU8&P=ML

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXCGCJ&P=7

George (gcb) enlightened me concerning both; this model and it's "pinch-corner" tank design. This thread might help you to understand the tank-concept.

http://clstunt.com/htdocs/dc/dcboard.php?az=show_topic&forum=103&topic_id=43082&mesg_id=43082&listing_type=&page=25

http://www.aeromaniacs.com/Tips.html

At the very bottom of this page is a link to a GIF image of the template.  Import the template into a program that allows you to stretch and size it (most word processors can do this, but are clumsy), then calculate the correct dimensions and stretch till you have them.  Print it out and verify.

Working in metric might be easier since 1 oz is practically 30cc

Make a matching wood plug to have an easier time about it according to the CLstunt thread.

Phil

pkrankow wrote: Make a matching wood plug to have an easier time about it according to the CLstunt thread. Phil

Yes.. I used plugs to build my tanks. I had (fortunately..) aluminum bar cut-offs to form the main tank-body and end-caps. Cutting "wood" plugs and shims really helps when soldering your tubes in. The wood doesn't sink as much heat away.

Although I've never tried it; you could probably build a conventional wedge-tank by making a plug; using a scrap piece of balsa "leading-edge" stock and hardening it with thin CA glue. Build-up the back side with hardwood to the depth (capacity) you want.. and glue it together for forming the tin sheet around.

Well, that's great info give here. I now know how this tank is supposed to look, as well as how to build it. Well, as soon as I can get my grubby hands on some metal, I will build it. Thank you all again for your help.