There seems to have been an explosion in the last couple of years in the availability of new power hammers, but I haven't run across any new hydraulic forging presses sized and configured for a small artist blacksmithing shop / studio (say something in a 20 to 50 ton range). Can anyone point me to any manufacturers or importers of such presses? Google didn't turn up anything relevant. I have seen plans for building a press, but I'll have limited time to devote to smithing for the foreseeable future and would rather spend it making stuff with a press rather than making a press.
depends on how "small" an artist you are. You can buy a 20 ton hydraulic press from Harbor Freight and lots of other places for less than $200. Then, if you have an air compressor, you can replace the 20 ton bottle jack with an air powered jack that fits right in there. Works great. I added a 1 inch diameter by 1 inch throw air cylinder to the air power jacks release valve and put valves for both up and down on the floor. Even without the air powered jack, these presses sure do the job. It just depends on how fast you want to go.
Are there such things ? Hydraulic presses have high static forces but are slow acting. Forging is generally done with hammers, either manually, mechanical triphammers or pneumatic - a relatively light hammer travels fast, giving a blow with lots of momentum but minimal long-duration force. The effect on hot metal will be quite different.
There certainly are, I have one. I first thought to post a web link to BonnyDoon Engineering, but they seem to have stopped offering their forging presses to focus on jewelery presses. I made mine based on plans from Jim Batson. Norm Larson carries the plans ( snipped-for-privacy@impulse.net).
Mine is a C style, jaws open on one side, backed up with an 18" web I beam. It is motorized and will reach 30 tons (36 ton design value, but I haven't found the increase necessary). The hydraulic pump is a log splitter pump which has two speeds, moving 4x as fast until the pressure trips it into 1x rate. With this kind of pump, a 2HP motor will propel a
30 ton press at about an inch per second. I originally set it up for 2" per second, but found this much too exciting for things like bending. The 1" per second is the unloaded travel speed (and usually the hot bending speed). During actual forging it slows to about 1/4" per second.
A motorized hydraulic press completely changes the way you think about thick pieces of metal. It is trivial to take a piece of 3" solid round,
8" long and squish it into a grapefruit sized chunk. You only get one shot at forging a given section of steel, but with the right tooling you can do some pretty complex forming in one stroke. Your tooling is much simpler--no impact, so you just weld up pieces of mild steel.
Where a hydraulic forging press really shines is in making pattern welded steel billets. It is completely trivial to forge weld an 8" x 2" x2" billet. Weld it once and the weld is good enough to draw it out on edge without any delamination.
A fun tool. If you make much pattern welded steel, I really think you're foolish if you don't have one. If I were doing it over, I would probably go with an H frame style. Batson has an addendum to his first plans which goes into some of this. Norm Larson can tell you about both. If you're thinking of making one, the log splitter pumps are insanely noisy at 3500 rpm, run them at 1750.
How fast do I want to go? Fast enough to finish forging before the metal cools significantly. I don't know what minimum speed would be required, but Batson's design uses two-stage pumps that provide a ram speed ranging from 1 to 4 inches per second (unloaded). What kind of speed are you able to get with the air-powered jack?
I've been leaning toward a C-frame, thinking the additional access would translate into increased versatility, so I'm intrigued that you would opt for the H-frame. What advantage does the H-frame offer, other than potentially being stronger and more rigid for a given structural weight?
Is the noise from the log splitter pump anywhere near as loud as a comparably sized power hammer? Are you aware of any other suitable pumps that would be quieter?
Thanks for the link Kelley. At least now I know that *someone* makes them, though I think I'd rather have a C-frame design rather than the H-frame design used in this press. I'm also a little apprehensive about all those exposed high pressure hydraulic lines -- it wouldn't be pretty if a piece of red-hot steel rubbed up against one!
I actually built a press similar to the smaller Bonny Doon press a couple of years ago. It's great for cold work (punching or forming sheet copper, for example), but it's way too slow to be of practical use for hot forging.
I can go at about 1/2" per second. This is fast enough to get about 3 or 4 presses per heat on 1 1/2" wide damascus billets, because you only have to release the press by a 1/4 of an inch or to take the next "bite". The welds we have made so far have been good. Currently my press is not in the same room as the forge, but I will put it on casters soon, so I can roll it up close to the forge when I want it there. I intend to use it for punching eyes in hammer heads, etc., too. We also have made a couple of different 10" wide press brakes that work well. You might be amaxed at how well this press brake makes 90 degree bends in 1/8" plate.
My press is built on a 7' piece of 18" web I beam, reinforced on the front edge with a piece off of a road grader 1" thick and 8" wide, top to bottom. It seems to me that you could do a couple of different things with an H style. You could make a "tabletop" model with *much* smaller I beams that be almost as versatile. You could also make one with large side beams spread farther apart, potentially giving you a much larger pressing area. That said, I don't have any limitations with my C, and don't know of anything specific I'd like to do with an H that I can't with a C. I guess a smaller unit appeals to me, no real advantage.
If you have a problem, you should be able to work around it by rotating your dies (maybe making a 90 degree set).
My friend Steve Rollert built his C style with the cylinder underneath, driving the lower anvil upwards (usually the top is driven with the bottom fixed). This sounds pretty weird, but it really works pretty well, and cuts your I beam length almost in half. Another idea.
Log splitter pumps are rated in the catalog for their gpm at 3600 rpm. I originally set my press up for 3600 rpm and 2" per second. Not only was
2" per second way too exciting, but a log splitter pump at 3600 rpm just screams. It is hard to believe it will survive long. I dropped down to
1750 rpm and was much happier. The noise a press makes is continuous, while most power hammers are impact, hard to compare them. I have a 50kg self contained air hammer. Its noise is pretty much continuous and about at the same level as the hydraulic press. At 1750 rpm, the noise is tolerable without ear protection; probably not good for you long term. I wear ear goggles anyway as loud continuous noises tire me out. I'll bet more expensive pumps get quieter, but don't know. Keep in mind that the pump doesn't have to be right at the press. It could be through the outside wall of your shop, or close by but in a sound deadening box. Heat dissipation is mostly through the oil rather than air flow (the oil reservoir needs to be large enough to shed the heat caused by friction).
spaco wrote in news:FLSdndERnP1xOEvfRVn- snipped-for-privacy@bright.net:
presses?
Speed is neccessary for general purpose forging with a hydraulic press. I do not make knifes so I can not speak to knife making. I have two pumps for my press one for die pressing and one for forging with a valve that selects the pump source.
The die pressing pump is a two stage 1 1/2 hp pump that produces 3500 psi to a 6 in cyinder ~50 tons.
The second pump is a 1.00 cu single stage gear pump (I believe) powered by a 7 1/2 hp motor and produces 7 gpm at 1500 psi into a 6 into cylinder to produce ~21 tons. The 7 1/2 hp pump moves the cylinder at about 1 inch/sec. This press is a little slower than a manual fly press but much more powerful.
Here is a nice site with a bunch of different home-built presses.
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It sounds like a lot of the pumps/flow rates have been pretty high. Moving a 5" cylinder at 1"/sec only takes like 0.25GPM, which can be had with a pretty low HP motor.
Check out
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for some calculators, etc. Seems like there would be a a lot of room for playing around with speeds, etc with most designs.
You've got a mistake somewhere, I'm not sure where.
A 5" cylinder at 1" per second requires 19.6 cubic inches per second pumping rate. A gallon has 231 cubic inches in it, so you need to pump 0.085 gallons per second, or 5 gallons per minute. At 1500 psi, this takes about 5HP.
Ahhhh...I know where it is. The location would be in my brain.
I was using the calculator to generate inches/minute, but reading it as inches/second since that's what I was interested in. What's a factor of 60 between friends?
I was a little surprised to have calculated such a low number in the face of the other specs, but I didn't bother to check my work.
Thanks for pointing out my error. I guess I'll go trade that 1/2 horse motor in for something bigger now...
Did you look at fly presses? some of them can develop high pressures and are very fast to use...bonus is that it is completely mechanical...no power requirement. try here if you want to see one:
A C-frame press of the same capacity would need to be significantly heavier to keep it from flexing. Any configuration will flex some but IRRC a cantilever, which is essentially what a C-frame is, has an extra factor to the power of four in the design calculations. That is huge scaling factor in a practical design. That's why most forging presses are H-frame or straight frame ( attached to one side of an I-beam).
I always hate to see rubber lines around hot metal too. It's not as dangerous as it seems since they are steel reinforced. However, it smells really bad when you hit them with hot metal. You can cover the lines with braided stainless sleeving to protect them.
Bert there are several commercial offerings for forging presses currently. These are aimed at the pattern welded steel makers primarily. One is from Swains Spring Service located in Great Falls, Mt. - another is offered by Pops Knife Supply - another (and I believe it is the best currently offered) is being made by Ron Claiborne in Knoxville, TN. A link to one I made for myself is
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and click on the shop tour page. You should be able to get info on the above presse's by Googling them. If not drop me an email and I will try to help you some more.
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