Reproducing a forged part
 

I need to reproduce a medium sized truck part from the 40's.

The original part had steel channel supports with various bends (90,
45deg) and radii (1 in, 4 in) made of 1/8th in steel. I looks like an
'S' made of steel channel.

Best I can tell is that the original parts were forged. No shop I
talked to would touch the part due to cost of dies etc. They assumed
that I would not spend the money (which I would have if they even
produced a quote).

ANyone have a source of practicle info on bending thick steel with a
plug mold (correct term?) type setup?

Thanks.

"P. Farber" wrote in message
...
I need to reproduce a medium sized truck part from the 40's.

The original part had steel channel supports with various bends (90,
45deg) and radii (1 in, 4 in) made of 1/8th in steel. I looks like an
'S' made of steel channel.

Best I can tell is that the original parts were forged. No shop I
talked to would touch the part due to cost of dies etc. They assumed
that I would not spend the money (which I would have if they even
produced a quote).

ANyone have a source of practicle info on bending thick steel with a
plug mold (correct term?) type setup?

Thanks.

Well, it actually sounds like a stamping, rather than a forging. Reproducing
the part by any kind of forming, in 1/8" steel, with 1" radii, would involve
enormous tooling expense.

However, you probably can have a perfectly serviceable replacement made by
weld-fabricating strips of 1/8" sheet, probably MIG-welding it together.

It still isn't going to be cheap, if you need to have someone else do it
all. Welding/fabricating experts no doubt will chime in here shortly and
explain the practical ways to get the pieces cut, welded, and finished.

BTW, what is the part, a frame cross-member?

--
Ed Huntress

Ed Huntress wrote:
"P. Farber" wrote in message
...

I need to reproduce a medium sized truck part from the 40's.

The original part had steel channel supports with various bends (90,
45deg) and radii (1 in, 4 in) made of 1/8th in steel. I looks like an
'S' made of steel channel.

Best I can tell is that the original parts were forged. No shop I
talked to would touch the part due to cost of dies etc. They assumed
that I would not spend the money (which I would have if they even
produced a quote).

ANyone have a source of practicle info on bending thick steel with a
plug mold (correct term?) type setup?

Thanks.


Well, it actually sounds like a stamping, rather than a forging. Reproducing
the part by any kind of forming, in 1/8" steel, with 1" radii, would involve
enormous tooling expense.

However, you probably can have a perfectly serviceable replacement made by
weld-fabricating strips of 1/8" sheet, probably MIG-welding it together.

It still isn't going to be cheap, if you need to have someone else do it
all. Welding/fabricating experts no doubt will chime in here shortly and
explain the practical ways to get the pieces cut, welded, and finished.

BTW, what is the part, a frame cross-member?

--
Ed Huntress


I think Ed is on track . Weld it up . I used a 50 ton press to form
1"X2"X1/8" channel . In a more open bend with home made dies . The dies
took no time to make but there was a fair bit of distortion . For my
application did not matter . Luck
Ken Cutt

I don't know where you are but You may want to check with Joe @
www.merlimfgco.com . I don't see it on his web page but he does reproduction
parts for old cars and locomotives. I know him form the Capital District
Blacksmiths, he host a demo for us every year. I don't know how busy he is
but a phone call might work better then e-mail.

Good luck

Andrew V

"P. Farber" wrote in message
...
I need to reproduce a medium sized truck part from the 40's.

The original part had steel channel supports with various bends (90,
45deg) and radii (1 in, 4 in) made of 1/8th in steel. I looks like an 'S'
made of steel channel.

Best I can tell is that the original parts were forged. No shop I talked
to would touch the part due to cost of dies etc. They assumed that I
would not spend the money (which I would have if they even produced a
quote).

ANyone have a source of practicle info on bending thick steel with a plug
mold (correct term?) type setup?

Thanks.

What was the part originally used for? S shaped... maybe a bracket on
the engine, or part of the suspension?

In many cases you can replace complex pieces with simple flat plates,
if you've no need to to look original and don't mind the extra weight.

Tim.

On Tue, 22 Feb 2005 00:20:40 -0500, "P. Farber"
wrote:

I need to reproduce a medium sized truck part from the 40's.

The original part had steel channel supports with various bends (90,
45deg) and radii (1 in, 4 in) made of 1/8th in steel. I looks like an
'S' made of steel channel.

Best I can tell is that the original parts were forged. No shop I
talked to would touch the part due to cost of dies etc. They assumed
that I would not spend the money (which I would have if they even
produced a quote).

ANyone have a source of practicle info on bending thick steel with a
plug mold (correct term?) type setup?

Thanks.

Without knowing the truck part you are talking about at all (I'm
guessing some sort of A-arm from the description) one way to
functionally reproduce a curve in bent square tubing like that would
be to fab it together as a box beam yourself.

Can you throw a picture or two in the Dropbox?

Have raw pieces for the sides of the curved box beam made by cutting
them out of flat plate with a plasma, water-jet or laser cutter, hand
bend strips of flat stock with a Hossfeld or roller bender to match
the curves for the flat sides, and weld together to taste. (If it's a
compound curve, both pieces would need to be CNC cut from plate, then
hand bent for the flat bends.) If you do a nice job of grinding the
welds, after paint they would be hard-pressed to tell it from bent
tubing. And I'd guess a lot stronger than the original bent tubing of
the same gauge, since the sides remain flat and parallel.

Does the part really need to be curved? Or can it be simplified
using cut and welded angle 'bends' on the square tubing, with gussets
or fishplates to spread the load? If you need custom A-arms to get
the vehicle back together and running (and are not looking for a
Concours D'Elegance win for a 100% accurate restoration) that will do.

Do more searching - if you come up with a way to duplicate the part
easily and make their availability widely known, you could make a nice
little cottage industry selling them. People ram cars into curbs and
break suspension bits all the time... And someone else might have
gone through the same trouble already.

(One big problem with selling them, though - you need product
liability insurance. Welcome to our sue-happy society.)

-- Bruce --

--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
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