No matter how you slice it, it's gonna be expensive. To get a fast action
you'll need a lot of flow from the pump, as well as high pressure, or a really
short stroke length which will limit the flexibility of the rig. Big high
pressure pumps aren't cheap; you get what you pay for. If you go the low
presure route, you'll need a large actuator piston to develop the force so you
can concentrate it in a small working area. Auto power steering pumps put up
around 500 psi, but you can run several in parallel to up the flow rate, and
they're fairly cheap and easy to get. You might consider an accumulator based
system, where the pump charges an accumulator which then feeds the power
piston. This will give you a high flow rate but a slow cycle rate, so you'll
get a fast stroke but slow recharge between strokes. Needless to say, having
lots of high pressure oil stored in tanks and plumbing can be dangerous, so
build with lots of overhead. SAFETY. If I was going the build one, I'd use at
least a 100% pressure overhead in the high pressure side ie 1000 lb limit for
a 500 lb system. Good luck...
Thanks for the info Charly.
I ahve about twenty vehicles out here in various stages of dis-repair so I
will be looking into the power steering pump method.
I need to learn some hydraulics anyway so this will be a good starting
I built a 30 ton forging press from Jim Batson's plans, which I highly
recommend. You can get them from Norm Larson ( firstname.lastname@example.org)
among other places (Norm is a pretty fine guy). There are two sets, the
first has a huge wealth of general info on how to put together a
hydraulic system like this and has plans for a floor standing I beam
based press. The second booklet has details on how to build a tabletop
model (same kind of tonnage, just sort of folded).
They are fine tools, you can do all kinds of stuff with thick metal. You
can't do a lot of forging on small stock. I've used mine to draw down
tong reins (with fullering dies). You can also take a piece of 3" round,
8" long and put it on end (hot) and smash it into a grapefruit sized
piece. I like taking large hex stock and squishing it into barrel shapes.
The way you make them move fast enough and have enough pressure without
a huge motor is to use a log splitter pump. These pumps are two
speed--at low pressure they pump fast, when the pressure goes above a
threshold, they slow down (about 4:1 I think). This way they don't chew
up a lot of horsepower. My 30 ton press moves at one inch per second
(no load) and runs on a 2HP motor. Their shafts can't take side
loading--you have to drive them with a coupler, not a pulley and belt.
If you're a good scrounge (very likely), the pump will be the most
expensive item. Cylinders can be bought new/surplus/used (see below); I
got mine at a country junkyard that had a lot of tractor parts. I bought
two 6" cylinders out of a trash truck for $75 (total).
Two mistakes in one that I made: the logsplitter pumps are rated to
operate at 3600 rpm. This is probably tolerable if they are on a gas
engine. On an electric motor, they absolutely scream. Don't run them
this fast, run them at 1800. Part two was that I originally set my
press up for 2" per second movement. This is ok if you're forging, but
the first time you bend something it gets really scary. 1" per second is
I built the I beam type. Mine is a 7' long beam with an 18" web (this is
a C style press instead of an H style). On the face of the beam is
welded a 3/4" x 8" wide piece of dozer blade for reinforcement. It is
large and heavy. Unless you absolutely must have a C style press, I
really recommend the H type. These work well in a 'table top' model. I'd
do it that way if I was doing it over.
A press *excels* at making pattern welded steel. Tack weld a billet
together on a handle (say 2" square and 6-8" long), flux it, get it hot,
and make it maybe 1/8 " thinner in the press. I do it once more just to
make sure (reheat and flux), then I go to drawing it out, flat or on
edge doesn't matter. No quicker way to make a bunch of pattern weld.
When I'm making tooling for the press, I try to figure out how to get
the most done in one stroke. Many times that's all you get before you
have to put the piece back in the fire (the dies suck the heat right out).
Pumps are not very expensive, they can be bought on industrial
liquidations for not too much and will have a lot of horsepower and
will likely be of exceptional quality. (of course you need to have 3
phase, which I assume most of you do).
You can buy hydraulic cylinders from a variety of sources, for example
I am selling cylinders with 8" bore, and about 24" stroke right now, I
have two. (shameless plug) They are from a military 50,000 lbs rough
Making a proper frame for a high power press is certainly a challenge
as far as making it safe and sound is concerned.
I would just look for a industrial A or H frame press at liquidations,
again, they are not expensive and it is easier to buy something made
than spend forever scrouging I beams and welding stuff and grinding
off bad welds.
600 ton press in Chicago. (A little hard to believe this number, be
I am not affiliated with the seller, though I bought quite a few
things on their auctions.
Same here. Could be a typo? That's not much cylinder _or_ frame for 600
tons, going by a guess at the size of the compressor next to it.
I could ask if my old employer is ready to sell the old press: 20' above
the ground, 20' in the ground, 40" ram, would reduce a 40" x 72" round
billet to 10" thick in about, oh, 10 seconds. Of course the billet was
at 2300 degrees at the time and the pressure was right at 5000 psi but
it was still one heck of a hydraulic forging press.
Oh, yeah, after the Big Squish, then they went and punched a hole in the
donut with an auxiliary ram mounted on the side of the main one. Somehow
I never got tired of watching that thing really: Squash, make flat!
Not _the_ biggest press around, but adequate for the home workshop.
Bring back, Oh bring back
Oh, bring back that old continuity.
Time for a gloat here. I just traded my monster Johnson gas
furnace for a pristine, 25ton,4 post shearing press! 7hp, 18x24 platen.
it's not the best configuration for forging but I'll make due or tear it
down and build it back as a c-frame design. I am more interested in
working sheet material anyway.
John Husvar wrote:
Does the flux ooze, or go supersonic? Sounds like too much flux though.
I have caught my share of it on power hammers. Owwww under my
gloove! left a 1/16" deep crater on my wrist.
Steve Smith wrote:
It reminded me a lot of someone spitting tobacco, much slower than flux
coming from hammering. Almost certainly too much flux on my part. I was
using plain borax.
What I picture is a pocket in the middle of a layer finally getting
enough pressure on it to find a outlet.
Not recommended for human tissue!! Ya think? I would like to do some
pattern welding on the press but it is set up more for die forming sheet
gauge metal. The top and bottom platens are about 24x18" with 4 corner
posts. So it is awkward to set up and change tooling. Better for forging
would be an open frame setup. A buddy used the hydraulics(25 ton 5hp)
from a wrecked cardboard compacting machine and built a double C-frame
from 16" I-beam. 36" throat and about 12"stroke. He shapes sheet and
plate steel on simple homemade dies. Works like gangbusters. It's a
good configuration for forging as well. Anyway, I'm waiting for enough
money to "rig" my press over to my shop. Got to scoot.
Steve Smith wrote:
I forgot to add sources:
If you're in Colorado, try Martin Salvage on Hwy 34 east of Loveland.
They have all kinds of interesting stuff off of old tractors and wagons.
Good for hydraulics
Steve Smith wrote:
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