Forging Press Design Question

[Dwane Oliver]

So I have finally gathered and scrounged enough materials to build a nice BIG forging press.
I want a single post press, I dont know what else to call it , that you can work from 3 sides.
Looking around the web and around here , I see some nice ones , like Mr Bumps.

http://knifedogs.com/showthread.php?14340-Basket-Weave-Damascus-in-a-Canister&p=133563#post133563

I was thinking.......(too much probably ) about putting the cylinder on the bottom, instead of on top.
This would drastically reduce the weight of the overall press, by not needing all of that beam below the dies.

Ok , I have never had the pleasure of using a press.
SOoo would this work ok?
Or would it be a PITA , with your material moving up and down with the cylinder.
OR are there other reasons that nobody builds them like that?


Thanks for any input you guys have


Dwane

 

[EdCaffreyMS]

I think that whether a press moves from the bottom or the top is gona depend on personal prefrence....and what an individual is accustom to. I've worked on both, and because I own the variety where the cylinder is top mounted, I prefer that type. However, my good friend Jim Clow has a super nice (an a monster of a press too) which presses from the bottom. I can do billets on Jim's press that are twice the size of what I can do on mine. The difference between the two is practicality....my press uses a 6" diameter cylinder, with an 8" stroke, whihc made top mounting managable. Jim's press uses a 10" (I think) diameter cylinder, which would be a nightmare to top mount. About the only thing I dislike about Jim's press is that is "hand" controlled, whereas mine has a foot control. Again, because I'm accustom to the fott control, I find I have more control with my press, because I can keep both hands on the billet/workpiece.

Usually folks refer to the type of press you're thinking of as a "C" frame. Genreally presses are built in either the "C" or "H" frame varieties.....each have it's own advantages and disadvantages.

YOU CANNOT "OVERBUILD" A PRESS! The last time I built a new frame for my press, I used nearly 20lbs of 5/16" wedling rod! I reguarly have to change out 3/4" thick dies because the force simply warps them to beyond unusable. There is so much heat and repitition of force with a press....you simply have to build it 2x what you think it needs, just to make is last for any amount of time. Flex is the biggest enemy of a press.....build it too light, which allows flex, and you make "diamonds" rather then squares, on the other side of the coin, I have never seen a disadvantage is "overbuilding" a press.

If you're not familar with working on a press, take your time to understand all of the forces involved.....keep your work under/over the "center of force" (keep the work/area you are pressing on, directly in line with the cylinder's ram). And finally, be aware that pressing something "off center" can easily result in the workpiece become a large bullet! As with an machine(s) we use....understanding it and respecting it are paramount to preventing accidents.

 

[rhinoknives]

Dwane,
I have never run a press myself ether, but before I built one I would see as many different and possible use as many before I commenced making one. Some day if I make a press it will be hydraulic because having teniduis ""Ringing in my ears" It was torturous after an hour or so the last time I was at a hammer in and they were running a 100lb Little Giant.

Good Luck, stay safe and most importantlyl! Have fun.

 

[Dwane Oliver]

Thanks Ed and Laurence for jumping in here and offering up your thoughts.

Laurence : I have done a ton of research on presses , but had never seen a bottom mount one. I'm going to build a "Rusty" power hammer as well : )

Here is what I have Ed.
8" cylinder with a 12" stroke , 2" rod
I have 12' of 10" X 10" 3/4" thick all around I beam , I dont know what it weighs total , but its all 2 guys can do to lift one end about 2' off the ground, LOL
I also have about 20' of 1" X 6" strap for the mounting points.
5Hp 220V 3 phase 11 GPM hydraulic pump , the pump specialist said it was a 2 stage pump , 1500 psi then 2200 psi
That , theoretically , should give me about 55 ton.
I definitely want a foot control for it.

This will be an ongoing build for a while , as I can only work on it in my spare time. Which there isn't alot of these days.
With the cows, pigs , and chickens.......hunting season , butcher time and the garden , AND keeping up with my orders.............well I'm pretty busy.
I will probably do a WIP in my forum on it.


Thanks again for the comments.
Dwane

 

[Travis Fry]

Only thing I can really add is some commentary to Ed's post re: Orange Crush, the press he describes that our mutual friend Jim owns. It's the only press I've ever used, so I'm not speaking from a position of a lot of experience here, but FWIW. A lot of folks prefer foot control rather than hand control, so I asked Jim about it one day. He told me he originally made it with foot control, but didn't feel like he had as much ability to apply force with precision, so he switched it over (or that's my memory of the conversation, anyway) for more finesse.

I'm used to hand control now, and will likely build that way when the time comes, but it sure would be nice to be able to use both hands on larger billets to save the shoulders. I haven't used foot control, but I agree with Ed 100% about the limitations of hand control. I'd recommend trying to use both types at someone else's shop(s) before you commit to a design on your own in order to experience firsthand the pros and cons of each. Or you could just build it either way with the knowledge that you'll get used to using whatever you end up with. If you've not had a press before, either way you go you wont regret whatever choice you make with respect to the controls.