Recently I've taken to making fuel tanks for model airplanes out of old
Dole pineapple cans (because they're tinned on both sides). The
construction is fairly simple: you make a tube, usually pentagonal,
that's the main body of the fuel tank. Then you make end caps for the
tube, you poke a few holes for the brass fuel lines, then you solder
everything up.

Right now I'm making the end caps the same way you'd make a box: I'm
cutting pie-shaped sections out of the corners, so that everything folds
nicely with no excess material.

But I'd like to do this the way the "big boys" do: I'd like to have an
end cap with no seams or slits or whatever. Is there a way to accomplish
this with hand tools? Somehow I think if I just made a female die out of
oak or whatever, and whacked a flat sheet into it with a male die, that
I'd end up with something either ripped or wrinkled.

So: How? Or, what terms should I be searching on?

--
http://www.wescottdesign.com

"Tim Wescott" wrote in message
...
Recently I've taken to making fuel tanks for model
airplanes out of old
Dole pineapple cans (because they're tinned on both
sides). The
construction is fairly simple: you make a tube, usually
pentagonal,
that's the main body of the fuel tank. Then you make end
caps for the
tube, you poke a few holes for the brass fuel lines, then
you solder
everything up.

Right now I'm making the end caps the same way you'd make
a box: I'm
cutting pie-shaped sections out of the corners, so that
everything folds
nicely with no excess material.

But I'd like to do this the way the "big boys" do: I'd
like to have an
end cap with no seams or slits or whatever. Is there a
way to accomplish
this with hand tools? Somehow I think if I just made a
female die out of
oak or whatever, and whacked a flat sheet into it with a
male die, that
I'd end up with something either ripped or wrinkled.

So: How? Or, what terms should I be searching on?

--
http://www.wescottdesign.com

TW:

You may want to look at a "dapping block" which uses
punches to drive sheet metal into correspondingly sized
hemispherical depressions. You could cut the
hemispheres out and solder on a ring for a neck which
would fit over your tube. That could could be threaded
or otherwise fixed onto your tube if you want to go that
far.

If you cut a circle of excess material in the dapped sheet
around your hemisphere, keep the punch in place and
hammer said surrounding material down to form a neck
assuming the diameter of the punch shaft is a little larger
than
the diameter of your tube.

Look up an image and the words will make more sense.
Dapping blocks are appropriate for malleable metals.
Harbor Freight is one site you may want to check for
an inexpensive offering.

If you have access to a punch press or more involved
tooling, there are other options.

Regards,

Edward Hennessey

"Edward Hennessey" wrote in message
m...

"Tim Wescott" wrote in message
...
Recently I've taken to making fuel tanks for model airplanes out of old
Dole pineapple cans (because they're tinned on both sides). The
construction is fairly simple: you make a tube, usually pentagonal,
that's the main body of the fuel tank. Then you make end caps for the
tube, you poke a few holes for the brass fuel lines, then you solder
everything up.

Right now I'm making the end caps the same way you'd make a box: I'm
cutting pie-shaped sections out of the corners, so that everything folds
nicely with no excess material.

But I'd like to do this the way the "big boys" do: I'd like to have an
end cap with no seams or slits or whatever. Is there a way to accomplish
this with hand tools? Somehow I think if I just made a female die out of
oak or whatever, and whacked a flat sheet into it with a male die, that
I'd end up with something either ripped or wrinkled.

So: How? Or, what terms should I be searching on?

--
http://www.wescottdesign.com

TW:

You may want to look at a "dapping block" which uses
punches to drive sheet metal into correspondingly sized
hemispherical depressions. You could cut the
hemispheres out and solder on a ring for a neck which
would fit over your tube. That could could be threaded
or otherwise fixed onto your tube if you want to go that far.

If you cut a circle of excess material in the dapped sheet
around your hemisphere, keep the punch in place and
hammer said surrounding material down to form a neck
assuming the diameter of the punch shaft is a little larger than
the diameter of your tube.

Look up an image and the words will make more sense.
Dapping blocks are appropriate for malleable metals.
Harbor Freight is one site you may want to check for
an inexpensive offering.

If you have access to a punch press or more involved
tooling, there are other options.

Regards,

Edward Hennessey


Harbor Freight calls it a doming block

http://www.harborfreight.com/25-piec...set-93539.html

"Edward Hennessey" wrote in message
m...

"Tim Wescott" wrote in message
...
Recently I've taken to making fuel tanks for model airplanes out of old
Dole pineapple cans (because they're tinned on both sides). The
construction is fairly simple: you make a tube, usually pentagonal,
that's the main body of the fuel tank. Then you make end caps for the
tube, you poke a few holes for the brass fuel lines, then you solder
everything up.

Right now I'm making the end caps the same way you'd make a box: I'm
cutting pie-shaped sections out of the corners, so that everything folds
nicely with no excess material.

But I'd like to do this the way the "big boys" do: I'd like to have an
end cap with no seams or slits or whatever. Is there a way to accomplish
this with hand tools? Somehow I think if I just made a female die out of
oak or whatever, and whacked a flat sheet into it with a male die, that
I'd end up with something either ripped or wrinkled.

So: How? Or, what terms should I be searching on?

--
http://www.wescottdesign.com

TW:

You may want to look at a "dapping block" which uses
punches to drive sheet metal into correspondingly sized
hemispherical depressions. You could cut the
hemispheres out and solder on a ring for a neck which
would fit over your tube. That could could be threaded
or otherwise fixed onto your tube if you want to go that far.

If you cut a circle of excess material in the dapped sheet
around your hemisphere, keep the punch in place and
hammer said surrounding material down to form a neck
assuming the diameter of the punch shaft is a little larger than
the diameter of your tube.

Look up an image and the words will make more sense.
Dapping blocks are appropriate for malleable metals.
Harbor Freight is one site you may want to check for
an inexpensive offering.

If you have access to a punch press or more involved
tooling, there are other options.

Regards,

Edward Hennessey


He's making pentagonal tanks...

"Rick" wrote in message
...

"Edward Hennessey" wrote in
message
m...

"Tim Wescott" wrote in message
...
Recently I've taken to making fuel tanks for model
airplanes out of old
Dole pineapple cans (because they're tinned on both
sides). The
construction is fairly simple: you make a tube, usually
pentagonal,
that's the main body of the fuel tank. Then you make
end caps for the
tube, you poke a few holes for the brass fuel lines,
then you solder
everything up.

Right now I'm making the end caps the same way you'd
make a box: I'm
cutting pie-shaped sections out of the corners, so that
everything folds
nicely with no excess material.

But I'd like to do this the way the "big boys" do: I'd
like to have an
end cap with no seams or slits or whatever. Is there a
way to accomplish
this with hand tools? Somehow I think if I just made a
female die out of
oak or whatever, and whacked a flat sheet into it with a
male die, that
I'd end up with something either ripped or wrinkled.

So: How? Or, what terms should I be searching on?

--
http://www.wescottdesign.com

TW:

You may want to look at a "dapping block" which uses
punches to drive sheet metal into correspondingly sized
hemispherical depressions. You could cut the
hemispheres out and solder on a ring for a neck which
would fit over your tube. That could could be threaded
or otherwise fixed onto your tube if you want to go that
far.

If you cut a circle of excess material in the dapped
sheet
around your hemisphere, keep the punch in place and
hammer said surrounding material down to form a neck
assuming the diameter of the punch shaft is a little
larger than
the diameter of your tube.

Look up an image and the words will make more sense.
Dapping blocks are appropriate for malleable metals.
Harbor Freight is one site you may want to check for
an inexpensive offering.

If you have access to a punch press or more involved
tooling, there are other options.

Regards,

Edward Hennessey


He's making pentagonal tanks...

R:

You're right. My bad. I'll wait awhile after running for
the brain to settle back in before taking the reading
comprehension
test again.

Regards,

Edward Hennessey

On Apr 2, 6:33*pm, "Rick" wrote:
"Edward Hennessey" wrote in message

m...





"Tim Wescott" wrote in message
...
Recently I've taken to making fuel tanks for model airplanes out of old
Dole pineapple cans (because they're tinned on both sides). *The
construction is fairly simple: you make a tube, usually pentagonal,
that's the main body of the fuel tank. *Then you make end caps for the
tube, you poke a few holes for the brass fuel lines, then you solder
everything up.

Right now I'm making the end caps the same way you'd make a box: I'm
cutting pie-shaped sections out of the corners, so that everything folds
nicely with no excess material.

But I'd like to do this the way the "big boys" do: I'd like to have an
end cap with no seams or slits or whatever. *Is there a way to accomplish
this with hand tools? *Somehow I think if I just made a female die out of
oak or whatever, and whacked a flat sheet into it with a male die, that
I'd end up with something either ripped or wrinkled.

So: *How? *Or, what terms should I be searching on?

--
http://www.wescottdesign.com

TW:

You may want to look at a "dapping block" which uses
punches to drive sheet metal into correspondingly sized
hemispherical depressions. You could cut the
hemispheres out and solder on a ring for a neck which
would fit over your tube. That could could be threaded
or otherwise fixed onto your tube if you want to go that far.

If you cut a circle of excess material in the dapped sheet
around your hemisphere, keep the punch in place and
hammer said surrounding material down to form a neck
assuming the diameter of the punch shaft is a little larger than
the diameter of your tube.

Look up an image and the words will make more sense.
Dapping blocks are appropriate for malleable metals.
Harbor Freight is one site you may want to check for
an inexpensive offering.

If you have access to a punch press or more involved
tooling, there are other options.

Regards,

Edward Hennessey

He's making pentagonal tanks...



Here is how to form the ends:

Make a male punch of seasoned maple, birch, beech; oak is too coarse
grained. Make its dimensions the same as the outside of your tank
body. Be sure to give those edges around which the metal forms a
generous radius... bigger is better.

Obtain a piece of polyurethane rubber medium hard, 1/2" thick, and fit
it into a pocket on a steel plate, ie. build a stout metal fence
around the rubber pad.

Place polyurethane pad and base into a 10 ton hydraulic press, place
your sheet metal blank onto the pad, place punch on top, and apply
pressure judiciously.

The blank should be prepared such that it is 3/16" or so wider all
around the punch.

Trim to fit.

Any remaining wrinkles can be ironed by gentle hammering onto the
punch.

Walla!

Wolfgang

On Apr 2, 4:27*pm, Tim Wescott wrote:
Recently I've taken to making fuel tanks for model airplanes out of old
Dole pineapple cans (because they're tinned on both sides). *The
construction is fairly simple: you make a tube, usually pentagonal,
that's the main body of the fuel tank. *Then you make end caps for the
tube, you poke a few holes for the brass fuel lines, then you solder
everything up.

Right now I'm making the end caps the same way you'd make a box: I'm
cutting pie-shaped sections out of the corners, so that everything folds
nicely with no excess material.

But I'd like to do this the way the "big boys" do: I'd like to have an
end cap with no seams or slits or whatever. *Is there a way to accomplish
this with hand tools? *Somehow I think if I just made a female die out of
oak or whatever, and whacked a flat sheet into it with a male die, that
I'd end up with something either ripped or wrinkled.

So: *How? *Or, what terms should I be searching on?

--http://www.wescottdesign.com

Metal spinning on a lathe?
http://www.youtube.com/watch?v=kqQdQ...eature=related
http://www.youtube.com/watch?v=um-biLfru-c

On Apr 2, 5:27*pm, Tim Wescott wrote:

*Somehow I think if I just made a female die out of
oak or whatever, and whacked a flat sheet into it with a male die, that
I'd end up with something either ripped or wrinkled.

So: *How? *Or, what terms should I be searching on?

--http://www.wescottdesign.com

I made some CPU water cooled heatsinks using wood male and female
dies. But I was using copper , not steel. Had no problems with
wrinkles or ripping. It was a while ago. I think I may have used a
three part die. A female die, A flat plate that clamped onto the
female die that held the copper to the female die. The flat plate
would have a hole for the mail die to go through. That would give you
a part with a flange on it that you would probably want to remove.

Dan

On 4/2/2011 8:55 PM, wrote:
On Apr 2, 5:27 pm, Tim wrote:

Somehow I think if I just made a female die out of
oak or whatever, and whacked a flat sheet into it with a male die, that
I'd end up with something either ripped or wrinkled.

So: How? Or, what terms should I be searching on?

--http://www.wescottdesign.com

I made some CPU water cooled heatsinks using wood male and female
dies. But I was using copper , not steel. Had no problems with
wrinkles or ripping. It was a while ago. I think I may have used a
three part die. A female die, A flat plate that clamped onto the
female die that held the copper to the female die. The flat plate
would have a hole for the mail die to go through. That would give you
a part with a flange on it that you would probably want to remove.

Dan

Here's a cheap dapping block set, might work on steel if it is thinish
and mild:
http://www.harborfreight.com/25-piec...set-93539.html


--
:3 )~

On Apr 2, 5:27*pm, Tim Wescott wrote:

So: *How? *Or, what terms should I be searching on?

--http://www.wescottdesign.com

You might have a look at electroforming.

Dan

" fired this volley in news:571be158-
:

You might have a look at electroforming.


Me... I'm going to try hydroforming at my first opportunity. That looks to
be the metal version of vacuum thermoforming, and I love the idea that I
might be able to make detailed sheet metal shapes without complex dies and
punches.

LLoyd

On Sat, 02 Apr 2011 16:27:47 -0500, Tim Wescott
wrote:

Recently I've taken to making fuel tanks for model airplanes out of old
Dole pineapple cans (because they're tinned on both sides). The
construction is fairly simple: you make a tube, usually pentagonal,
that's the main body of the fuel tank. Then you make end caps for the
tube, you poke a few holes for the brass fuel lines, then you solder
everything up.

As an alternative: Would Coke cans work? You can sand blast the
printing off of Coke cans with baking soda. I would think a small sand
blaster using canned air (like you spray out your computer keyboard
with) should be relatively easy to make. Cut the Coke cans to size.
And then TIG weld the two halves together. Probably would work best
with a backing ring (also cut from the Coke can) for the weld. TIG on
the fittings.

The aluminum construction would be less weight in an RC airplane.
Dave