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I Forge Iron
Derek Melton

Bliss\Punch press?

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It's been covered multiple times here already.  Difficult as a press like that has to turn over if it locks up due to the workpiece being too thick it  can self destruct.

powerhammers have built in springiness to allow for differing thickness without resetting it in the middle of a heat.

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It's an interesting thought but it'd take some serious re-engineering.  Punch presses are all about inertia to move a specific pre-set stroke.  That stroke doesn't vary (unless mechanically reset) so if you were to hit an immovable object like trying to whack a hot bar that didn't want to move, the press crank will fail with a spectacular show.  Therefore you'd need a flexible link between the hammer and the fly-crank system to absorb the material variations.  

Then you have the issue of not being able to vary the inertia of the blows-no such thing as making a light blow because the mechanical linkage is not designed for that.  

Stroke speed is not remarkable on these either.  Nor is effective stroke length, most being in the range of 4" at their maximum stroke setting (that'd affect the available inertia of the hammer blows)

By the time you resolve the issues, you are probably into the time and cost to start with a proper hammer in the first place.  Not that you couldn't make an interesting project of it but so much would have to be modified that if you chose to take that route, you should probably start with a rusty old trashed press to begin with.  It'd be quite a hack job to make happen and you'd probably end up using little but the main frame--the easy part to fab from scratch int he first place.

However, at times those old presses show up dirt cheap so it's at least worth some thought....Sometimes doing things the hard way is a reward in itself.

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Thomas & Kozzy have covered this well, a few yrs. ago I helped my brother in law clean out his shop and we scrapped 10 of these  a couple about 3 times this size.  I was offered any of them for my shop but passed will not do the  job of a hammer.  Great for what they  were designed for. 

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Definitely not a power hammer but I know of several (at least 5) commercial blacksmiths' shops that use these for tooling intensive repetitive operations.  The late great Grant Sarver shows forging under one in one of his videos.  Note that they are for high precision highly repetitive production situations, not a flexible multi purpose machine.  A single die pack used in one will probably cost more than a hobbiest's yearly tool budget many times over.

Pull off the flywheel and crank and install a hydraulic cylinder and you will have a general use tool. 

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These machines are undervalued today.

For those capable of building tooling themselves the uses are limitless, from punching holes in strap hinges to blanking flat stock or bending an offsett or notching pipe. It is a production machine though, 1000 hinges at $15 each not one pair at $200.

Several local blacksmith shops have a row of punchpress for hardware manufacture.

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On 28/10/2016 at 3:48 AM, Judson Yaggy said:

[...]Pull off the flywheel and crank and install a hydraulic cylinder and you will have a general use tool. 

hi! is there any example of that ?

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I wouldn't mess with it, that is a very nice machine. I have access to one, and I came here asking the same question. It seems more practical to leave it as it is and find dies for it. This bad boy has no problem eating sheet metal for breakfast. 

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these mechanical presses store masses of energy in the flywheel, if they are set wrong and cannot complete a stroke it will be bad.

something will break

had a flywheel come off when a van I was driving at high speed, luckily it stayed on the crankshaft but there was not much left of the shaft or the casing when it stopped spinning.

the flywheel on this press may weigh 50 times as much

a hydraulic press or a power hammer comes down with a controlled amount of force, a mechanical one comes down until it stops the flywheel dead or something breaks.

when I first left school in 76 a place I worked at had 2 that stood about 16 feet tall, they each had flywheels weighing between 3 and 5 tons, they were not in use whilst I was there

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