Got a guy who welds up dune buggies and whatnot..and called me today
about finding him a punch press so he can stamp out various bits and
pieces for the kits he is planning on selling
His requirement was 3/8" max and no more than a 3" diameter stamping
I told him Id study up on it and see what I could find him.
Smaller foot print is prefered of course.
Where do I start?
Any suggestions, ideas and so forth would be appreciated
Looked in my 1943 Die Engineering Layout and Formulas book. A nomogram
in the back only goes to 1/4". I checked a 3" circle at 1/8 and 1/4, and
it seems to a bit more than double the tonnage. So checked 3/16 and got
about 45 tons, to give approx 90 tons for 3/8. Clearance will have an
impact on actual tonnage. I'd say at least 100 tons, maybe more just to
Given that he's got to make dies for everything, might be better off
finding a used CNC plasma table?
3/8" and 3" will take a 100 ton unit for steel.
Maybe hunt up an Ironworker with the large punch option, those will take
up to a 4" punch. New they run about 16K. Should be able to find a used
one for 5-6K.
I have a 50 ton that I picked up years ago for 2K in VERY good shape.
I just talked to him..and he says he has a $30,000 CNC plasma
cutter..and under 1"..the sides of the holes are NOT square.
Its not a "high definition" plasma, but is only a couple years old.
Now he is talking about down to 2" holes in 1/4" plate..max....wish he
would make up his mind.
There are some 45 tonners in So Cal on Ebay I told him to check on.
Well I was thinking not only of saving the die making time and expense,
but the ability to crank out parts as he needs them. He could easily set
up programs to make a family of parts in one setup vs X number of setups
I think 45 is light for 1/4". I wouldn't put that job on my 60, the whole
building would shake. There are tricks of scalloping the die to reduce
needed pressure. It will deform the scrap strip. If you scallop the punch,
that will deform the blank. I would farm it out to somebody with the right
equipment or find a supplier for a standard blank.
As I understand it, a punch press typically has a motor and flywheel
and clutch. Sizing those for your parts is the task at hand, and...
in terms of building dies and handing them to a shop that has
a half-dozen punch presses, and asking for a small run of parts.
The footprint is just the storage rack of the dies, and a shop that
a variety of sizes of press can determine the best size for any given
part. You get the full benefit of their multiple presses without
the monthly upkeep and rent (for a few-minutes-per-month kind of
Many of the modern presses use hydraulics instead of a flywheel.
The guy builds dune buggies and race cars and is a full time LA county
fireman. So he has a full plate. I know Ive brokered a rather nice
LaBlonde lathe and a Bridgeport for him in the last 6 months..so he has
to be doing fairly well to be buying tools of this dollar value.
As a lot of his work is done when he is off shift etc etc..he cant
depend on needing a Lefthanded Widget made up for him at 4am, when he
suddenly discovers he needs one to bolster the trailing watchcallet on
the upswept doofunny.
So he needs to be able to do it himself when he needs one.
First law of stampings: If you don't need many hundreds of thousands, farm
it out! I have nine presses and I STILL farm out low-volume or intricate
parts. I'm lucky in that most of my parts are round and thin and the dies
are easy to make and last decades...or until an oops.
_Machinery's Handbook_ has a section on the calculation of the
tonnage needed for different thicknesses, different hole perimeters, and
different materials (brass and mild steel are what I remember being
3" diameter is 9.42" perimeter, or about a 3" square for this
I somehow don't think that this will be very small or light. If
he can be more patient, an eletrically pumped hydraulic press might do
better -- but you still will need a lot of metal to support the
I've got a 1-1/2 ton punch press which I can carry without too
much difficulty, but this would be on the order of about 1/4" diameter
hole in 1/10" brass - a *lot* less than what he wants. I think that
he'll need a fork lift to position what he needs.
Start with your copy of _Machiery's Handbook_ of course. It is
almost two o'clock (AM) so I hope you will forgive me for not looking it
up in my copy right now. :-)
I broker lots of short runs in funny shapes in metals from s/steel to
brass to titanium, in thicknesses from 1/16th in to 1/2in plate.
i use a laser profiling co. without exception. I either give them a
pattern to copy or a drawing. They then digitize it, and laser profile
Theres no cheaper or faster way to produce up to say 200 of any one
Thyey supply the metal as well. Turn round time is usually 5 working days.
They allways give me a price up front, and I allways pay on collection.
They can digitize up to A1 drawing size.
Great co.But there no use your friend as were in the UK.
They can also do 3D work on tube up to 4in dia.
In Dorset in UK.