Converting an inverted hydraulic press into a light-duty forging press

[JHCC]

Eliminating the horizontal bar would certainly make it easier to get the pieces I need out of my chunk of 1/2” plate, but I’ll still need a 5” x 5” piece in the center as the core of the upper die holder. Probably be good to add a gusset in the middle to keep that from bending.

 The diagonal stiffeners can’t run from the die holder to the upper corners of the bridge without hitting the corners of the posts. However, I could clip those corners and weld the stiffeners to them thus:

[JHCC]

On a bit of a tangent, it’s kind of interesting to know when your drops were made and where they came from:

And speaking of such information, I found a small label on the side of the press frame that says "Property of A & I Products". A little internet research tells me that A & I is a manufacturer of aftermarket replacement parts for agricultural and industrial applications, based in Rock Valley,  Iowa. I suspect that my press may have been left over from their days as a machine shop and sold to HGR when they were retooling or something like that.

[Frosty]

If you make the 5" x 5" die holder from 1/2" or thicker it will be very rigid. The diagonals are 1 1/2" wide each. 1 1/2" x 2 + 1/2" for the bridge member = 3" this only leaves 1" on each side unsupported. The vertical members you sketched don't add to the structure, they focus the upwards pressure in ONE point. The diagonals distribute the bending moment of the die over the entire length of the bridge member converting it from bending moment into tensile. 

Lose the vertical stiffeners, they make it structurally weaker.

Consider how much harder it is to pull a piece of 1" sq. mild in half compared to 20" of it. I don't have numbers in front of me but they should be available if you're interested. Bending 1/2" x 6" the hard way is so far beyond the capacity of a 25 ton cylinder almost any reinforcement is over kill. 

Clipping the inside of the posts won't hurt and welding the diagonals to them will make it even more rigid. The diagonals don't HAVE TO extend into the corners, they'll do more than enough where they reach.

Or, you could raise the bridge member an inch. This will help make up for the posts being shorter than you'd prefer.

Good sketch, no need to draw the parts we aren't talking about.

Frosty The Lucky.

[JHCC]

24 minutes ago, Frosty said:

If you make the 5" x 5" die holder from 1/2" or thicker it will be very rigid.

Hmm...I think I might have a sufficiently large chunk of 3/4" thick in the back of the bin. I will check.

I'm also thinking of not having the bottom die holder extend the full width of the opening. Instead, I'll make it 5" x 5" -- the same as the top die holder -- and put a piece of the 1/2" x 1-1/2" on edge at either end of the removable guide, thus:

This will enable me to weld almost the entire perimeter of the die holder onto the angle iron. I don't know if the pieces on the ends are strictly necessary, but they'll give a bit more bearing surface to the guides and also keep the ends of the angle iron in a fixed position relative to each other.

26 minutes ago, Frosty said:

Clipping the inside of the posts won't hurt and welding the diagonals to them will make it even more rigid. The diagonals don't HAVE TO extend into the corners, they'll do more than enough where they reach.

In that case, I think I'll leave the posts as-is and simply have the stiffeners go from their locations on the die holder to the inside of the tops of the posts, welded top, bottom, and sides. Less cutting, and easier to fit.

29 minutes ago, Frosty said:

Or, you could raise the bridge member an inch.

I think the bridge will end up being a hair under 7". My chunk of 1/2" plate is 11" wide, so if I cut 4" off the bottom to make the bottom guide, that will leave plenty for the bridge -- and will save me having to make a second lengthwise cut. Again, less cutting, and as long as the bottom edge is straight and both ends are square, whatever happens with the top edge doesn't make any difference.

[Frosty]

1 hour ago, JHCC said:

I'm also thinking of not having the bottom die holder extend the full width of the opening. Instead, I'll make it 5" x 5" -- the same as the top die holder -- and put a piece of the 1/2" x 1-1/2" on edge at either end of the removable guide, thus:

YES. Making it full width WILL tempt someone, maybe even you to use it off center. If you keep all the forging centered over the ram it'll hold itself together. Thicker die holders is good but don't get too carried away, I wouldn't go heavier than 3/4".

1 hour ago, JHCC said:

This will enable me to weld almost the entire perimeter of the die holder onto the angle iron. I don't know if the pieces on the ends are strictly necessary, but they'll give a bit more bearing surface to the guides and also keep the ends of the angle iron in a fixed position relative to each other.

I'd weld the die holder to the angle iron saddle/clamp pieces.

The guides I don't see YET are the ones on the bottom guide that prevent it from cocking between the posts. It won't take much, four each square bars welded parallel with the posts on the die guide. Use a business card spacer between them and the posts to allow clearance so nothing jams in use. Yes?

1 hour ago, JHCC said:

I think the bridge will end up being a hair under 7". My chunk of 1/2" plate is 11" wide, so if I cut 4" off the bottom to make the bottom guide, that will leave plenty for the bridge

Perfect. I use a guide when making long cuts, just a straight bar thick enough it won't heat and warp while I'm cutting. The major trick is keeping the torch tip the right distance off the plate so it cuts nicely. 

I'm not normally into cosmetics so long as a thing looks like it works properly. However the cut across the top of the bridge member is going to be like a billboard, I'd go to a little extra effort to make it a pretty torch cut. Of course that's just me and I take pride in not having to hide my welds, torch work, etc. under paint. Vain ain't I? 

Frosty The Lucky.

[JHCC]

43 minutes ago, Frosty said:

YES. [...] Thicker die holders is good but don't get too carried away, I wouldn't go heavier than 3/4".

Sounds like a plan.

43 minutes ago, Frosty said:

I'd weld the die holder to the angle iron saddle/clamp pieces.

Yes, that's what I was thinking.

44 minutes ago, Frosty said:

It won't take much, four each square bars welded parallel with the posts on the die guide.

Are you suggesting welding them to the 1/2" x 4" guide that's running on edge? That's an option, but would make it impossible to remove that bar. I could weld them to the inside of the angle iron saddle/clamp pieces, though. That would give me as much bearing surface but still allow disassembly.

49 minutes ago, Frosty said:

I use a guide when making long cuts, just a straight bar thick enough it won't heat and warp while I'm cutting. The major trick is keeping the torch tip the right distance off the plate so it cuts nicely.

Not having a cutting torch, I'm planning to make the cut with a cutting disc in an angle grinder. The bottom edge of the plate is (I believe) already nice and straight, so that won't need much adjustment, and a good disc cut will mean less cleanup after.

51 minutes ago, Frosty said:

However the cut across the top of the bridge member is going to be like a billboard, I'd go to a little extra effort to make it a pretty torch cut.

That edge of the plate was torch-cut, so I'm prepared to blame whoever cut it originally.

[Frosty]

11 minutes ago, JHCC said:

Are you suggesting welding them to the 1/2" x 4" guide that's running on edge? That's an option, but would make it impossible to remove that bar. I could weld them to the inside of the angle iron saddle/clamp pieces, though. That would give me as much bearing surface but still allow disassembly.

It was too late to edit my post when that occurred to me. Weld them to the angle iron clamp, ayup you got it. 

 

13 minutes ago, JHCC said:

Not having a cutting torch, I'm planning to make the cut with a cutting disc in an angle grinder.

Cutting disk in an angle grinder. . . UGH! Better than turning the blade 90* in a hack saw, using what you have is the rule.   

Oh yeah, take credit for the good stuff. Another fine tradition to observe.

Frosty The Lucky.

[JHCC]

6 minutes ago, Frosty said:

Weld them to the angle iron clamp, ayup you got it.

It occurs to me that if I weld up the saddle/clamp first, I can grind the ends nice and smooth (and square), bolt it to the lower guide, and use that as a jig for welding the posts both to the table and to the bridge. Since the lower guide and the bridge are coming from the same stock, that would align the posts perfectly, and I could then skim the bearing surfaces off the guide to get just enough clearance for smooth operation.

Since those joints are all under compression, I suppose I could get away with wire welding them before Tom & I get together to weld up the frame.  

[Frosty]

Using the saddle as a jig to weld the posts is a nonstarter where I'm concerned. The welds WILL pull and either clamp the guide tight or open up. No, you need to jig and weld the posts as stand alone structure so you can tweak it square. 

The posts need spacers to form guide tracks. 1/2" strap stock with a business card spacer. The bridge member should also have card stock spacer to prevent the pull from warping the structure. The spacer on the table top can be removed after the posts are welded IF you can get it loose.

The bottom die guide  is floating. The dies, the center of  the bridge member and angled stiffeners are under compression. The posts from the bridge member to where they weld to the table are a tensile structure and need to be welded properly. A poor weld is a failure initiation point, literally a COLD SHUT.

I see where I threw confusion into the discussion. When I said it's all under compression and will hold itself together I meant the die holders where they connect to the guide and bridge member and dies.

That's my bad, I'll have to watch what I say more closely. 

Frosty The Lucky.

 

[JHCC]

2 hours ago, Frosty said:

you need to jig and weld the posts as stand alone structure so you can tweak it square. 

OK, that makes sense. 

So if I understand you correctly, the sequence would be something like this:

1. Weld right front post to table, making sure it is square to the top.

2.Weld left front post to table, exactly 10” to the left of and coplanar with the right front post, square to the table top. 

3. Using a piece of 1/2” bar stock and a business card as a spacer, weld the right back post in place.

4. Using the same size spacer, weld the left back post in place.

5. Put the bridge in place with a piece of business card between it and the front posts on both left and right. Weld in place. (This means that we’ll be welding over a business-card-thickness-sized gap, yes?)

6. Weld on stiffeners.

7. If possible, knock out spacers.

Sound about right?

 

[Frosty]

Yeah, that's about got it. I'd still weld in a couple 1/2" + card stock spacers between the legs mid point or spaced to prevent flexing in use. Yes you'll be welding over a gap, it's insignificant if you clamp it hard before tacking. 

Rather than square to the table top as your final say, double check the table isn't slightly warped or doesn't move when you run a bead. It's thick enough it shouldn't pull much if any but it's been in hard use it's whole life and may have taken a bit of a bow. That ram has been pulling up to 25 tons on that spot for who knows how many years. Or does the tag say? It's an easy check and too easy to not get surprised. Your framing square should be plenty of good straight edge to check it. Yes?

Frosty The Lucky.

[JHCC]

2 hours ago, Frosty said:

The dies, the center of  the bridge member and angled stiffeners are under compression. The posts from the bridge member to where they weld to the table are a tensile structure and need to be welded properly. 

Understood. What I’m saying is that (as discussed previously) the posts at very least need to be stick welded top and bottom, and probably the top die holder and the stiffeners as well. However, since the saddle, its gussets, the bottom die holder, and the dies are all under compression, they can be wire welded if necessary, right?

[Frosty]

3 minutes ago, JHCC said:

However, since the saddle, its gussets, the bottom die holder, and the dies are all under compression, they can be wire welded if necessary, right?

Correct, you could probably silver solder them but don't get silly. 

Frosty The Lucky.

[JHCC]

38 minutes ago, Frosty said:

it's been in hard use it's whole life and may have taken a bit of a bow.

Actually, it’s bowed up about 3/16”-1/4” across 24”, so more than a bit. However because most of that is in the center where it’s not a problem, I might be able to fix it with a little judicious grinding in the areas where the posts will attach. Frankly, as beat up as the top is, some pre-weld cleanup is probably a good idea anyway. 

In other news, I got most of the pieces cut out and mocked up:

[Frosty]

As long as the bow in the table doesn't throw the posts off it's all good. 

The mock up looks pretty good. Do you have enough to run the diagonal stiffeners higher? They'll be okay but higher is better.

Are we having fun yet?

Frosty The Lucky.

[JHCC]

5 hours ago, Frosty said:

Do you have enough to run the diagonal stiffeners higher? 

Maybe; I’ll check later. 

[JHCC]

5 hours ago, Frosty said:

As long as the bow in the table doesn't throw the posts off it's all good. .

Unfortunately, it does: it drops a fat 1/32” over the width of each post, which means each post leans outward about 5/32”. Added together, that means the tops are about 5/16” farther apart at the top than they are at the bottom. 

I’ll double check the squareness of the post bottoms and see if there’s any arrangement that makes them all stand straighter relative to each other. 

[JHCC]

Would it be possible/worthwhile to weld up the frame nice and square, and then weld it down onto the table?

[Dasher]

Sorry for dropping in JHCC, just offering my 2c worth.Without going to the rigaramol of straightening your table top, that would be a good option for mine, fully assemble the upper works, nice and square, then seat, and trim as necessary for a good , full pen weld on the verticals, the table top probably has an induced curve from it's previous life, and would be a beast to get dead straight again, depending on your expected loadings, you could reinforce the underside with 2 pfc's back to back, but unlikely needed for your intent, once the upper works are fully completed and landed, they will in turn reinforce that small span with sound welds.

[JHCC]

Welcome to the discussion, Dasher; all suggestions welcome!

15 minutes ago, Dasher said:

Without going to the rigaramol of straightening your table top

I wouldn't need -- or want! -- to straighten the entire tabletop, just where the posts attach to it. That would be two areas about ~5" square, 10" apart. The space in between isn't critical, as it isn't in contact with any part of the mechanism or structure.

18 minutes ago, Dasher said:

you could reinforce the underside with 2 pfc's back to back

"pfc" = "parallel flange channel" = "C-channel", for those who don't speak Strayan. And yes, that would be unnecessary: the top isn't under any load that would require that additional reinforcement.

[Dasher]

Better to trim your verticals to suit, rather than trying to level 2 small areas for them, the working distortion between the risers is minimal, and will have near nil effect on your pressings I feel, keep it simple I'd suggest and not overthink it. [ it's nice to say that 'cos I overthink stuff all the time] lol.

[JHCC]

4 minutes ago, Dasher said:

Better to trim your verticals to suit

Definitely worth considering, and fairly easy to do on the belt grinder. 

.

[Dasher]

Thinking about it a bit more JHCC, I don't think I'D bother trimming them 1/32" over that distance, just do a normal weld prep, and may be a little less on the on the web and outside flanges  as it gets higher, and just run your fillet weld , major loading is going to be on the inside flanges anyway, and a sound weld there will make all the rest insurance anyway

[JHCC]

The bottoms of the posts are already ground really clean and square, so I wasn't planning on touching those. I do need to prep the tabletop, though, so I can go a bit deeper on the inner part of that cleanup.

It occurs to me that if I clamp the pieces together really, really solidly, that will give me a good reference for how much (if any) needs to be removed from the table and where.

[Dasher]

For 1/32" over the length of that channel web, I wouldn't bother, just a tiny bit more gap for penetration on your weld.