More punching on the Hydraulic press...

[Larry L]

I did some playing today and built a table with a through hole for the press.... I wanted to see if I could do a pretty big hole .... 1 5/8" was the largest round alloy bar I had so I made a 1 5/8 punch and drift..



In the press




And the hole..... 1 5/8 through 1 3/4 thick by 2 1/2 wide.... Not quite in the center but not bad for a first go....

I did learn I need a more secure way to hold the tooling... my 1/2" set screw is not cutting it.. I need to figure out a quick change bolster set up as well...

[Larry L]

Here is a video to give you an idea how fast the press is moving..


its a 6.5" bore cylinder 25gpm max pressure about 40 ton

http://www.flickr.com/photos/28780485@N08/4962801724/

[Grant]

Sorry Larry, I don't think you're even moving 10 GPM! Take a look as the speed of my 8" cylinder with a 12 GPM pump: Upsetting tongs

[david hyde]

Good stuff Larry

Kinda curious about the bottle in the right of the lower picture which seems to have "Nitro Monster" written on it

[david hyde]

Larry the threaded end to my cylinder gives me more options but how about the idea below for a quick and easy, almost quick change punch holder. You don't have to unscrew the bolts all the way out, just a few turns.

Quick change bolsters should be easy

[Larry L]

Larry the threaded end to my cylinder gives me more options but how about the idea below for a quick and easy, almost quick change punch holder. You don't have to unscrew the bolts all the way out, just a few turns.

Quick change bolsters should be easy

Attachment 870

The thing that would concern me with that system is upsetting the shank in the holder... I suppose if you where using all tool steel the chance would be smaller but still you wouldnt need to swell the shank much at all for it to become welded in there.... If the base was broad and flat (rather than skinny and deep) maybe that would be less likely to swell?

[Larry L]

Sorry Larry, I don't think you're even moving 10 GPM! Take a look as the speed of my 8" cylinder with a 12 GPM pump: Upsetting tongs

Yeah Grant your cylinder is hummin.... I dont know. This is the third power supply I have tried all with known output.... The previous two where a 10HP 8GPM and a 15HP 13 GPM and this one is significantly faster than the 15HP unit....

[Larry L]

Good stuff Larry

Kinda curious about the bottle in the right of the lower picture which seems to have "Nitro Monster" written on it

Yep thats right..... Nitro Monster it is.... The energy drink of choice for those late night monster metal forging sessions.... Also goes quite well with a quality Blanco Tequila

[david hyde]

The thing that would concern me with that system is upsetting the shank in the holder... I suppose if you where using all tool steel the chance would be smaller but still you wouldnt need to swell the shank much at all for it to become welded in there.... If the base was broad and flat (rather than skinny and deep) maybe that would be less likely to swell?

Not the best of engineering drawings!!! I should have shown a bit of clearnace between the walls of the "hole" that the top of the punch sits in (ie the punch will rattle without the collar). This stops any problems with upsetting. The 45 degree shoulder on the punch and the female 45 deg on the collar will locate the punch as the bolts are tightend and stop it moving sideways. If not punching off centre, most of the force is straight down so you don't need large 45 degree shoulders.

My Kingsland (none quick change) steelworker uses the same principle and 45 degree shoulder to locate the punch and the shoulder is only about 4mm wide. It's only a 40T machine but some of the bigger beasts use the same punches. It has a screw on collar (which takes time to unscrew) but the path of the forces involved would be more or less the same as with a bolt on collar

[Larry L]

Interesting. I'll do some playing and report back