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spkrman15
02-19-2008, 10:24 PM
I mad an attachment for bending metal with my 20 ton, air over hydraulic operated press. I have since bent some of the parts i made for bending the metal, but wow is it amazing what these machines can do.

This is a lock for a farmers top link. You can't really see it, but i have a 1/2 moon machined in the lower end, so that when the arm is perpendicular to the top link, it rotates. Push it down and it locks.

http://i168.photobucket.com/albums/u172/Spkrman15/DSCF0159.jpg

This is the locking band

http://i168.photobucket.com/albums/u172/Spkrman15/DSCF0160.jpg

And my first try! Oops!

http://i168.photobucket.com/albums/u172/Spkrman15/DSCF0161.jpg

In total, about 1 hour of work, including the mistake and heating up the garage.
Rob :)

torker
02-19-2008, 10:44 PM
Rob, my 12 ton press is one of the most used tools in my shop. I've made all kinds of bending dies, fixtures for straightening snowmobile suspension arms, even made a set of dies that make 20 guage "weld in" Chevy Bowties for the hotrod crowd. The 12" wide 90* brake gets the most use. I've made hundreds of trailer stake pockets with this.
I still haven't mounted the new 20 ton air/hydro jack yet. I did try the air jack in the core splitter I just built and was amazed at how effortless the whole process was.
Russ

Bill in Ky
02-19-2008, 10:47 PM
Nice work there. A press would we handy.....

spkrman15
02-20-2008, 06:47 AM
When i did work an the brake press at the door factory, i looked at their dies. Their homemade dies were not as complicated as i imagined. Now the dies for the press those were precision devices, but the stuff for crimps, holes, etc weren't that difficult. You just have to use your imagination i guess. That Bow tie emblem would be cool. Have any pics ?

Rob :)

torker
02-20-2008, 07:19 AM
Rob...whew...good one! That die set is in the last stuff I packed to move up here. I'll have to see if I can find it.
You are right about some dies being simple.
I worked in the R+D dept at a larger farm equipment factory in Saskatewan one winter. We made a lot of prototype dies for the big presses. If they where in a hurry for parts some of our mild steel prototypes would end up getting used for short production runs. Some lasted pretty well... others not so great.
They had a big ol' mechanical press there. It was over 20 feet high and had an 8 foot diameter flywheel on it. That was the one that would eat our homemade dies for breakfast. That thing used to scare the crap out of me.
Used to make a "Clacketty BANG" noise everytime it came round. The building was about 1/8 mile long... huge by my standards. That big ol' press would shake the entire building.
Was sort of comical in a way... a small farm town turned into a manufacturing mecca of the praries. Everyone in the town worked there. You could always tell the people who worked on that big ugly press. They all had at least one finger missing :D
Russ

GKman
02-20-2008, 07:58 AM
They had a big ol' mechanical press there. It was over 20 feet high and had an 8 foot diameter flywheel on it. That was the one that would eat our homemade dies for breakfast. That thing used to scare the crap out of me.
Used to make a "Clacketty BANG" noise everytime it came round. The building was about 1/8 mile long... huge by my standards. That big ol' press would shake the entire building.
Was sort of comical in a way... a small farm town turned into a manufacturing mecca of the praries. Everyone in the town worked there. You could always tell the people who worked on that big ugly press. They all had at least one finger missing :D
Russ

Had a version of that at Greene Company in Kansas City named "The Killer" of course. Looked like an 8' tall horseshoe magnet bent out of 12" square stock in shape. As you say "Clackety Bang" as a dog engaged with a spinning flywheel (5' or 6' on this version. The bottom jaw would slowly raise crushing whatever was in it and USUALLY reset. when it DIDN'T it would double trigger and repeat about the time you were reaching in to retrieve the stamped part. The control? A big foot bar so you could crush both hands and your head in there all at the same time if you were so inclined. When OSHA started they gave up on the whole damned building and started over.

Your Old Dog
02-20-2008, 08:00 AM
I've had one as part of my museum and have just started getting some use out of it a few months ago. I'm fascinatted by press fits. Feel like I'm getting away with something !! I have the HF 20 ton on sale for $169, sure was a good buy. (the bird dropping weldment on this one look like maybe the bird was a little runny instead of the clumped up absolutly cold weldment stuff LOL)

BobWarfield
02-20-2008, 11:18 AM
Pix of fixtures and attachments?

BW

GKman
02-20-2008, 02:45 PM
Think I got the idea from Torker. Two sizes of dies and last project. Ten Gage roof truss hangers. With all the bends I only had to make one weld on each one. Six inch long 90* bend was all Harbor Freight 12 ton wanted to do. Everything has to be dripping with oil to do that.Tools just welded up mild steel. Accidentally put a piece of 1/2" hard round in one and it left a 1/2 circle dent made die look like it was made of modeling clay.

http://img.photobucket.com/albums/v494/gkman/P2200041.jpg

BadDog
02-20-2008, 03:32 PM
I've got the "20T" HF press and several dies that look almost exactly like that, longest is 20"...

BobWarfield
02-20-2008, 07:26 PM
Is there a particular book or books someone could recommend to learn more about these dies? I want the "How to Run Your Southbend Lathe" type of thing for presses and dies if someone could suggest such a thing.

GKman, you are right, the dies look easy and the results are pretty darned nice. Thanks for posting.

Reason I'm so curious is I got a deal on a 45 ton air-over-hydraulic press. It's a real beauty, but I've yet to think of something good to do with it. Looks like a few dies would help that out a lot!

Best,

BW

fishfrnzy
02-20-2008, 10:15 PM
for bending dies, a few rules of thumb.

for mild steel

Bottom die opening should be 6-8 X material thickness.

Top die (called punch) should have radius of 1 X material thickness.

bottom die for bending to 90 degrees should be about 85 deg inside angle to allow for sprinback of material.

do not try to bend flat bar in line with the grain beyond about 20-30 degrees or it wil likely crack.


I have seen dies made such as shown with cold rolled square bar(gives you sharp corners and straight stock) welded with corners vertical and have heard they ar very servicable. Also have seen them milled from solid bar and a;so made with angles welded with legs down on a flat plate and heel up forming a V between the two. Don't use the id of an angle or you will only be able to bend about 80 degrees and without alot of support it will fail.

some reference info below


http://midwestpressbrake.com/

wierdscience
02-20-2008, 10:58 PM
Good job!

One of the first jobs I did on my own was 60 bent step treads out of 1/4 x 6 diamond plate.The corners where knocked off at a 45* and the ends bent up with a 1" radius in the corners which basically made a 20" long 6" wide U shaped step. I did all those on a 20to Alcan press,manual.I used my left arm so it would bulk up and match my right:D

Scray presses?Not a press,but a shear,a 20x5/8" Chicago mechanical from about 1920.Two 70" od x 20" wide flywheels,one on each end.The guys put grease in the clutches which would make them stick in.It would cycle once,stick in and start picking up speed:D

It had these enormus springs up top to decelerate the ram as it fell through the lighter gauge steel.The springs were retained by some dish shaped steel caps big around as dinner plates and probibly 2" think.Over the years rain water would build up in the dish and rust the tie rods running up the center.Oneday they had rusted through enough to break sending springs,rods and caps raining down around the operator:D

ligito
03-05-2008, 07:32 PM
How can I make a die to bend 1/8 x 1, or 1/8 x 1 1/2 into a clamp that resembles a 3/4 in. ID double screw conduit clamp?
What would it look like and what would I need to make it from?
I have a 12 ton press.

spkrman15
03-05-2008, 09:07 PM
Ok i am not totaly sure what a double screw conduit clamp is. I have an idea so i will go with that. The best way is to build a male and female die. By pressing them together, the metal will be forced to take the form of the dies. I think your 12 ton press could do that easily.

Now i am not a press expert. There are many more on here that are. Maybe if you posted your question in a new thread you might get more detailed and acurate responses.

Good luck and let me know how it goes

Rob :)

ligito
03-05-2008, 09:12 PM
I will, thanks.

mr bill
03-05-2008, 09:27 PM
when making male and female dies - how much clearance do you make between the two? The thickness of the metal to be bent? plus a little? Example: If you are making a rib between the two dies.

tigmusky
03-05-2008, 09:52 PM
great thread guys, i'am in th middle of bluilding a 20n ton air/hyrd. shop press just to make some bending dies. keep the pics and rules of thumbs comeing. Hopefully next weeek i can add some pix. daye

torker
03-05-2008, 10:44 PM
Geez.. I almost forgot about this. Here's my ol' Bowtie Die. Found it in a bucket out in the snow :D
The "pressure cover" is missing. It's a piece that goes over the sheet stock when it's in the die. You clamp it down so the sheet edges can't crinkle up on you as you are shaping the bowtie. You have to get the clamping pressure just right or it'll rip the corners out as the sheet can't slide as you use it up by pushing it into the hole.
http://img.photobucket.com/albums/v210/torker/DSC00001-41.jpg
Russ

spkrman15
03-06-2008, 10:20 AM
Russ,

Did you use your Plasma to cut that out? Those are some pretty clean edges.

Rob :)

torker
03-06-2008, 10:27 AM
Rob...no I made this long before I had a plasma cutter. I used a torch, grinder and (gulp) files. Took a looong time. Plasma would be far quicker.

spkrman15
03-06-2008, 10:56 AM
Wow Russ,

That is some nice work. Filling after using a torche. UGH! Hehe how many did you end up making when all was said and done?

Rob :)

torker
03-06-2008, 11:36 PM
Rob, I forget how many I sold...maybe 30 or so. Was selling them for $25 each when I used to go to car shows.
How many I made??? I think I wrecked about 30 or 40 trying to get the die right. Had lots of trouble punching the corners out. Also had a lot of trouble figuring out the right pressure for the "pressure cover" or slip cover. That thing is the key to this die working. I have to find it then I'll show you the end product.