[How do I?] Need Some Help. Need To Make A Lock Washer Stamping Die?

[Mutt]

Hey y'all, I am sure there are some real experienced minds here. I have never needed to make something like this, but I need to now. I can't use hardware store stuff, it has to be this size.
Can someone explain how to make this die, so I can stamp out a bunch of these? They will be for actual use and resale as "new", so they can't be just a haggard piece of metal/ I got a 20 ton press and I'm sure it will stamp 21 gauge.
.032" thick, .170" i.d., .412" o.d. I've tried a few washer makers. They either won't do it at all, or want me to buy 1 million of them ..............

 

[TOOLMASTER]

USUALLY MADE OF SPRINGS I BELIEVE

 

[TOOLMASTER]

 

[TOOLMASTER]

...........

 

[Mutt]

I know there has got to be a way other than buying a $50000 machine, I saw one guy using his chuck on his lathe and his tail stock to punch the center hole. Any one got any other ideas?

 

[TOOLMASTER]

.......CLOSE

 

[Terrywerm]

If it were me I would be taking a real close look at something that is commercially available already. You will probably need to have them heat treated after they are stamped so that they retain the correct amount of 'spring'. Will they need to be plated too?? I don't know how many of these you need, but making them will drive the actual cost per piece awfully high compared to what is already available.

 

[JimDawson]

By the time you get done building the die for these, you will understand why they want you buy a million of them. There are 3 operations there, punch the center hole, blank the outside, and split/form. Blank and split/forming could be done with a compound tool, but it would add a layer of complexity that may not be worth doing for a low volume production run.

A .170 punch and die button, and the .412 blanking punch and die is readily available from Dayton Progress http://www.daytonlamina.com/punch-die

They could also make the split/forming punch and die, or you could do that one yourself.

Given the material thickness of 0.032 you will want about 0.003 clearance between the punch and the die. So a 0.172 punch will require a 0.175 die button. Urethane strippers should work well in this operation, they would save you the trouble of making stripper plates.

What material do you plan on using and will it be heat treated after forming? How many parts do you need to make? Is it worth getting a small punch press?

The blanking operation will require the most tonnage at about 2 tons assuming 1095 steel, annealed. The tonnage (and tool wear) goes up if it is hardened. It looks like this could be done in a 20 ton press. You will need a die set or other method of holding the tooling in precise alignment. I would recommend a 4 post like below for use in a hydraulic press, much more stable than a 2 post. I would also recommend ball bearing slides.


This sounds like a fun project.

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[Mutt]

If it were me I would be taking a real close look at something that is commercially available already. You will probably need to have them heat treated after they are stamped so that they retain the correct amount of 'spring'. Will they need to be plated too?? I don't know how many of these you need, but making them will drive the actual cost per piece awfully high compared to what is already available.

I have found nothing close enough any where. I have a nice digital Paragon heat treating oven, so that's not a problem. the plating is also not a problem as I have parts cad plated quite often.

 

[Mutt]

By the time you get done building the die for these, you will understand why they want you buy a million of them. There are 3 operations there, punch the center hole, blank the outside, and split/form. Blank and split/forming could be done with a compound tool, but it would add a layer of complexity that may not be worth doing for a low volume production run.

A .170 punch and die button, and the .412 blanking punch and die is readily available from Dayton Progress http://www.daytonlamina.com/punch-die

They could also make the split/forming punch and die, or you could do that one yourself.

Given the material thickness of 0.032 you will want about 0.003 clearance between the punch and the die. So a 0.172 punch will require a 0.175 die button. Urethane strippers should work well in this operation, they would save you the trouble of making stripper plates.

What material do you plan on using and will it be heat treated after forming? How many parts do you need to make? Is it worth getting a small punch press?

The blanking operation will require the most tonnage at about 2 tons assuming 1095 steel, annealed. The tonnage (and tool wear) goes up if it is hardened. It looks like this could be done in a 20 ton press. You will need a die set or other method of holding the tooling in precise alignment. I would recommend a 4 post like below for use in a hydraulic press, much more stable than a 2 post. I would also recommend ball bearing slides.


This sounds like a fun project.

.
.

I need to make 500 of them. Thanks for the link to the punch/dies. That will be a big help. 1095 is a good choice, hopefully I can find some in a sheet form and I can shear it into strips. What do I look for in a "small" punch press? I am sure I could find other uses for it down the road