Forging press I-beam length

JTknives

JTknives

Blade Heat Treating www.jarodtodd.com
Knifemaker / Craftsman / Service Provider
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Jun 11, 2006
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So I'm getting much more serious in at least rounding up the parts for my press build. I got to use salems C press and like that style. So with that in mind I came across a section of I beam that I'm thinking might work. It seams rather beefy and from flat to flat measures 16". The only catch is that it's only 36" long and I'm wondering if I can squeeze in all the required "stuff" onto this 36" area and still have a usable stroke.

I was looking at different rams from surplus center and it seams like you can get some rather short ones. I'm looking for some advice on weather or not this is worth going after. I will try and get a pic and some actual dimensions. Thanks guys.
 
Here are a few pics, as you can see it's rather beefy

Photo%20Aug%2012%2C%205%2006%2018%20PM.jpg


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Photo%20Aug%2012%2C%205%2006%2039%20PM.jpg
 
I think you're onto something with the idea to use a trunnion mount cylinder. Then you could have fairly long throw still. And, the lower die/foot it sits on can be butt-welded and scab-plated onto the bottom end to conserve more space. Mine is made that way with full pen 7018 stick welds and it's held up great.
 
I'm going to draw something up when I get home but I think I can make plates that bolt on each side with a trunnion hole. This way it's locked into place and all the load goes into bolts in a shear load. I wonder if my AC buzz box can handle this kind of welds. Maybe if I do some heavy weld preps. If not then I guess I will just have to load up and go visit my good budy on the other side of the Columbia ;), he needs more 15n20 any way.
 
A trunnion mount may not be as good as an end mound due to the possible vector. Those type cylinders at used where the cylinder has to rotate to maintain a straight line to the point of force ( like moving an arm at an angle). Because the pivot is forward if the line of force, some of the energy will be transferred into trying to rotate the cylinder. This will put side force on the guides. It probably isn't a big deal until you start using many tons of force, then it may cause a problem.

I would cut that big I--beam in half to make the top and bottom of the C-frame, and get a 5' long piece of something heavy for the spine.
 
You have some good information on that beam. It is a wide flange 16x57 (57 pounds per foot of length.) You can T that beam and weld a cap on the web side of the beam and still retain strength. They do it in structural applications all the time. You should be able to find all the info you need with a search. It will most likely be a 4x5.4 channel.
 
I think I'd use that for the top and bottom of the press and hold out until I got a longer piece for the vertical.
I know you're anxious.
This is something you only want to build once and you don't want to look backwards wishing................
You may regret not having a longer stroke.
 
So just for the sake of asking what do you consider a good stroke for a press.
 
If you want to use it to do a feather pattern

You need double largest billet thickness plus a little clearance for the chisel

If you use a eye punching tool for axes ans hawks, it will have to account for that length


Make it big enough that you can make a press brake attachment and get it in there
 
JTknives said:
So just for the sake of asking what do you consider a good stroke for a press.
Click to expand...

I built my H-Frame to have 14" of daylight between the die plates and 10.5" of stroke. It means I need relatively tall forging dies but I figured at some point having that much daylight available would be useful.
 
kuraki said:
I built my H-Frame to have 14" of daylight between the die plates and 10.5" of stroke. It means I need relatively tall forging dies but I figured at some point having that much daylight available would be useful.
Click to expand...
I built mine so that with 1/2" thick die plates + 1" thick dies I would be 1/2" short of extending the ram to full length with the dies touching. That way I would never risk extending the cylinder beyond its limits and causing unintentional damage.
 
Karl B. Andersen said:
I built mine so that with 1/2" thick die plates + 1" thick dies I would be 1/2" short of extending the ram to full length with the dies touching. That way I would never risk extending the cylinder beyond its limits and causing unintentional damage.
Click to expand...

Yep, it's good insurance I think. My cylinder should be fine being fully extended, but my draw dies and flat dies will be tall enough to do exactly what you're saying too.
 
If your beam has a little flex in operation, you can always buy and cut plate gussets to fit in as an added web on either side. I'd almost recommend doing that anyway for most presses, it makes the beam rock solid and closer out towards the edges of the flange where you slider plate goes. I think I paid 80-90 bucks for enough new A36 plate to add webs to my H beam. It can be stitched in with interrupted beads, continuous is not necessary.
Kuraki has a good point there about having more daylight than ram extension, and then normally using tall dies or the lower die on a riser... this gives the ability to remove the riser to begin a tall cut, and then finish the cut with the riser in, on a second heat, if you want to cut feather with a shorter ram.
The trunnion mounts on cylinders are right in line with the axis of force, and indeed if your press is beefy and built straight with a heavy slider adjusted to have minimal play, the cylinder will see a whole lot less side load or deflection than it would in many heavy machinery applications, even when drawing and doing things not strictly in the center of your dies.
I'd think the trunnion mount, if properly fabricated on your frame, is a very good way of compensating for a relatively short beam. I have a couple 8" trunnion mount cylinders with 21" stroke, recently I found some very large beam to build a press upgrade with one of them, but it would be too short I believe without taking into account the cylinder mounts. So I think for my next press build I'll be going the way you are contemplating.
 
I agree that with good guides, the defection issue will be largely moot. I was mainly pointing out that it would need to be addressed in the build. I am looking at this from an structural engineering point of view.

The other thing to consider is the strength of the trunnions, since they only seat in sockets, not a through pin.
A 2" through pin run through a 1" plate on each side of the eye would be plenty strong in a standard build for almost any size press. All the force would be delivered straight up into the header beam. As long as the header was strong enough, there would be no issue.
A 2" trunnion pin would need to be seated in a large and heavy steel block on each side. The block's welds and bracing would carry the entire force of the press - roughly 10-15 tons each side. This isn't all that hard to deal with on an H frame, but on a C frame, you only have one side to attach the blocks to. Still, doable, but to be considered.
 
You're spot on there... should work fine, but has to be built very stout at the mounting blocks. "Doable, but to be considered" describes very concisely much of the crazy stuff we do!
 
I have wondered how many large cannons blew off their mounts because the trunnions sheared off, or the mounting blocks tore away. I know I have seen salvaged cannons with one sheared trunnion.
 
you can forge with a cannon? sounds like a good video
 
If your press has a trunnion won't it have to wear orthopedic shoes?:eek:;)
 
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