I find myself in a somewhat awkward position with this subject,
being a person who often gets asked what sort of equipment is needed
to use the dies that I make for people. I have always simply told
folks about the various varieties of mechanical device that involve
being able to squash small items with varying degrees of pressure.
The discomfort comes from knowing about several versions of hydraulic
press that are made by very nice people, most of whom have bought
custom dies from me at one time or another, and knowing that when I
recommend one option, Iâm leaving someone else out.
I have a lot of experience with crude, manual contraptions that I
started with, before I was aware of a press designed specifically for
this type of work, then a 50 ton Carolina H-frame shop press, and now
the original recipe Bonny Doon models, 20 and 50 ton. I have also
just recently talked with Phil Poirier about the re-design and
upgrade of the BD press line, and am convinced that those are
certainly the toughest, most durable ones available. I do not have
any engineering education or training â being a former jeweler,
designer, bench-working monkey, etc.-- so I am not qualified to offer
an in-depth, comparative, technical analysis of all the different
competeing presses, but Philâs detailed explanations of the upgrades,
and some of the research behind that, made it clear that the BD
presses are top of the line products.
They tested the 20 ton frame with a 100 ton ram and did not destroy
it. Impressive. I also got good advice on how to reinforce my old BD
50 ton frame, which will save me the trouble of building a custom one
myself, something thatâs outside my comfort zone of capability. While
itâs clear to me that those are the toughest frames, it should not be
taken to mean that I think other metalsmith-targeted presses are not
good, or are not worth buying. (here I am, right in the middle of the
mine field again, same as it ever was⌠(cue âOnce in a Lifetimeâ by
Talking Heads )).
The most important thing for me in this position is to be honest, and
I feel better too, giving the disclaimer that I am not knowledgeable
about engineering. So, my opinions are my opinions only and I donât
claim to know all there is to know about presses in this field. Maybe
I should just overstate the obvious,that there are several options
and possible choices to be decided between, for the prospective
press- purchaser. If someone tells me that they tested their 20 ton
frame with a 50 ton ram, I canât argue that this is a sturdy, useful
product, and I would tell a person interested in presses the same
thing Iâm saying here : that I know of some (20-ton-rated) that I
wouldnât even feel safe using at 20 tons, that I know of one that
works at 20 and was tested to 50, and that Iâve heard of one that
tested to 100 tons. The decisions about which to buy are not mine to
make. If an apparently good product fills a desirable price range
itâs hard to say to a person that this is not a good choice, because
it may be a good choice for them.
The thing about the BD design is that the original was around for a
long time and was proven reliable, and the upgraded ones are made to
far exceed the rated capacity and far exceed the original design.
The Potter press hasnât been around long enough to have been time
tested, but it looks to be a good unit, and fills the price-range
gap left by the upgraded BD line. None of this is a secret, or hard
to grasp, so in that regard perhaps Iâm being overly cautious in
expressing myself. There are other people making presses designed
after the original BD, and they are what they are, which is to say,
one could do better and one could do worse. People needing long
term, maxed-out-pressure cycles should definitely look at spending
more, but not everyone can afford that route, or needs to go that
route. Again, this is common sense, not biases, or personally
motivated ideas.
Phil also explained why the H-frame shop presses are not a very good
way to go, certainly not for forming work, and as it turns out, not
even for blanking, long term. I did use a 50 ton âHâ for several
years, but not even the heaviest blanking jobs, with several pancake
dies being used at once, ever took more than about 20 tons. So that
frame was never really taxed, and we never found out what itâs long
term life was going to be. Phil can explain it better, but those
frames are designed for slow buildup and release of pressure, and
the relatively rapid rise (I used air/oil pumps on this one after a
while) and definitely-immediate release of pressure causes extreme
flexion in the frames, which will lead to metal fatigue and eventual
failure. Another concern with cheap imorts is materials and
construction quality. So itâs âbuyer bewareâ (maybe even âbe afraid,
be very afraidâ) with those.
Arbor presses work well on small items. I have a 1 ton that I use
and abuse for breaking in dies after heat treating, and itâs the
only way to go for that particular job, which does involve blanking
parts out to get the dies loosened up after I crack them open the
first time. Of course the Rio screw press was designed for pancake
die use, and (checking to see if itâs still being made⌠nopeâŚ)
is/was well suited for blanking small to medium parts. But this
topic is âhydraulic pressesâ, so Iâll leave off now, and with a good
feeling, that Iâve been honest and fair, and maybe a little
informative.
Dar Shelton
SHELTECH