Mechanical presses do they have any uses for forging?

[redbate]

Came across this thing at a used machinery dealer the other day. It's a John Heine 12 ton mechanical press. Can these be converted to be used for forging? Price is really good but that's all I would need it for. 

[ausfire]

Nice machine. John Heine made these punch presses way back in the 1800s. We have one in our museum but it's not as complete as the one in your photo. I guess it could be used for all manner of pressing applications with the right dies - making cup shapes, candle holders and so on. Especially good for repetitive work. Pity it's in NZ ... I would have it if it was for sale here.

[Carson]

Mechanical presses were preferred over hydraulic for hot forging for about ever. The only reason you see hydraulic used now is because they are easier to build and for modern operations, they can be set up to given strokes and pressures more easily. That is of course just my opinion, but not totally unfounded. The fact is that mechanical press will move metal and fast. There is no pump lag, fluid cavitation or anything in the way. 

[ThomasPowers]

Perhaps we differ in our definition of a mechanical press but they were used very little in the blacksmithing world; only when you get into drop forging do they excell and drop forging is a HIGHLY constrained process where each step MUST match the die perfectly in temperature and mass to be manipulated.

This has been discussed here a lot of times.  The problem with that sort of press is that there is no give in the system. A typical powerhammer can work stock that is a wide range of sizes over the finished size. A punch press cannot!  Furthermore It has to complete it's stroke . If not it can break or get stuck.  Breaking is very dangerous with chunks of metal flying around.

So fo an example; You heat a 25mm bar and stick it into your mechanical triphammer and hammer one end down to  a taper ending at 6mm (depending on your powerhammer that may be one heat.)  Now for your punch press you need to build a set of progressive dies to do that and it probably take several heats to use the progression.  If you decide to change the angle of the taper you just do it on the powerhammer starting and ending at differing points on the stock. For the press you make a different set of dies....

So if you have a specific size of stock and want it worked to a specific end point and can make the dies for each item then the press can be quite useful.  To randomly grab a piece of stock heat it and beat it into shape mabe changing that shape in process a punch press won't work and may cause severe injuries!

[redbate]

18 hours ago, ausfire said:

Nice machine. John Heine made these punch presses way back in the 1800s. We have one in our museum but it's not as complete as the one in your photo. I guess it could be used for all manner of pressing applications with the right dies - making cup shapes, candle holders and so on. Especially good for repetitive work. Pity it's in NZ ... I would have it if it was for sale here.

There's a few other they have for sale here <commercial link removed> feel free to impulse purchase and import them

 

12 hours ago, ThomasPowers said:

Perhaps we differ in our definition of a mechanical press but they were used very little in the blacksmithing world; only when you get into drop forging do they excell and drop forging is a HIGHLY constrained process where each step MUST match the die perfectly in temperature and mass to be manipulated.

This has been discussed here a lot of times.  The problem with that sort of press is that there is no give in the system. A typical powerhammer can work stock that is a wide range of sizes over the finished size. A punch press cannot!  Furthermore It has to complete it's stroke . If not it can break or get stuck.  Breaking is very dangerous with chunks of metal flying around.

Yeah this is what I was worried about. Thank you.

[JHCC]

@redbate, please don’t quote the entire post you’re responding to. It really eats up bandwidth and makes the forum run slowly for our members still using dial-up. 

Instead, highlight the key point you’re responding to, click the “quote this” button that will pop up, and type your own comment, thus:

4 hours ago, ThomasPowers said:

a punch press won't work and may cause severe injuries!

Yeah this is what I was worried about. Thank you.

[Frosty]

Welcome aboard Carson, glad to have you. If you'll put your general location in the header you might have IFI members within visiting distance. 

There have been stamping presses modified for some forging operations, the most successful I'm aware of was turned into a chasing machine by  fellow name of Roger I believe. Various chasing chisels and Roger was able to do some nice chasing in hot steel pretty fast. It was a small stamping press about 300 lbs. IIRC.

These things aren't designed to forge, they're designed to stamp sheet metal and punch holes, Dad had 3 in his shop and I used to spend plenty of time on them. 

A proper mechanical "press" would be more like a screw press when the tooling stops the flywheel does too. A stamping press's trip engages a dog between the flywheel shaft and the eccentric that drive the tooling. Lock one up before bottom dead center and you'll be LUCKY to shear the dog but those are really REALLY tough. You're  more likely to experience a catastrophic failure in the crank arms ( connecting rods between the eccentric and top die) right in front of your face.

We had a new acquisition in Dad's shop demonstrate why it'd been surplussed by jamming which caused the fly wheel to slip off the shaft and roll across the shop floor. Didn't upset Dad a bit, he heard what went wrong and fixed it without trouble. Losing the flywheel is why Dad preferred that particular make, they were designed to slip the wheel if they jammed. And no, nobody had a station down range from a punch press's flywheel.

It's a tempting thought but . . . 

Frosty The Lucky.

[Carson]

Ok, first let me say I'm new here and no one should take anything I say as gospel. That said, I'm going to try this one more time. I did do a search in presses form back a couple of years and do not think anyone has discussed this type of press. So here it goes.

This is not an arbor press or a dedicated punch press. What we are looking at here is an industrially produced mechanical press with an air clutch. It is not a blacksmithing tool any more then a mig welder would be. It is a machine for hot and cold forming, punching, and shearing. It is not a hammer and can not do what a hammer does. It can, however, do some things a hammer can not do.

Basic operation goes like this: 

You plug it in and the motor provides direct power for the press operation. The power from the motor can not actuate the press until air pressure is applied to the clutch. The regulated air pressure determines the point at witch the press will kick out. Maximum air pressure gives the rated pressure at the linear shaft by allowing a sun/planet gear to turn a crank. There is no ratchet or progressive lock pin. Foot pedal plus air to the clutch makes it go down and when it reaches the limit of the clutch or the foot is released, it goes up. Unless this machine has been thrown down a flight of stairs, it has a 50% catastrophic failure rate well beyond a hammer or hydraulic press. 

What it does and how it does it:

Simply, it will use open or closed dies to preform work. If your dies can reliably work at rated pressure, and you don't seriously overload them or use hot short iron, this is as safe as it gets for the pressure. Hammers will rip top dies off handles and send them flying. High pressure steam or hydraulic fluid will cut pieces off of you before you can flinch. This will only do the rated work. It will not send rays of hot metal through the air. If metal exits the die, it stops moving. Maybe it could fall, but probably just oozes like cookie dough. This is not a drop hammer. The dies do not have to contain the metal.

The active stroke is in the range of 0 to 1 or 2 inches. The daylight maximum is 6ish inches. More or less on a machine this size. You have to set the stroke, the throat and the dies. That takes 2 minutes or more. The kick out of the clutch can be adjusted on the fly. This machine will reduce, taper and form cross sections in material with open dies and can leave a smoother finish then a hammer much like a hydraulic press but at a faster rate with shorter stroke. It can head bolts, pins and rivets with closed heading dies. It can crimp, cabbage, bolster, and yes, pierce with either open or closed dies. 

It's limitations are a short stroke, it's smallish size and it's need to have both electrical and pneumatic service. As with any machine,  it would need to have all moving parts thoroughly examined up to and including a magnaflux. 

Tl;dr:

It's not that bad

Edit: Thanks Frosty, I'll do that. Only just read your reply. This is sheet metal sized, but Chambersburg was making air clutch hot work presses I know in the early 1970s. Not common, especially now with linear drive, but they do more then an ironworker.