Punch Press: Recommendations?

[gr8legs]

If you have a table on your turret press you could just clamp a stop to it like this.
Just line it up with the punch that is the diameter of your washer.

View attachment 228280

Denny

That is an excellent suggestion - unfortunately neither of my punches has an attached table . . . . but making a jig will be pretty easy so no worries. Thanks!

Stu

 

[Glenn Brooks]

So what is the thickest diameter a small punch press will 'punch'? Less than 3/16" mild steel?? So a better question is, Is there some kind of rule of thumb between the relationship between tons of pressure and thickness of the work? Iam mostly intrigued by what it would do with steel.

Thanks
Glenn

 

[Ken from ontario]

So what is the thickest diameter a small punch press will 'punch'? Less than 3/16" mild steel?? So a better question is, Is there some kind of rule of thumb between the relationship between tons of pressure and thickness of the work? Iam mostly intrigued by what it would do with steel.

Thanks
Glenn

It is mostly a relationship between the top punch and the bottom die, if the material is of heavier gauge, the wider bottom die is used, for example, to punch a 0.250" hole in (14 Ga) mild steel, the top punch would be .250" and bottom die would be around . 265". the heavier/thicker the gauge(in mild steel), the wider the bottom die will have to be.

 

[Rustrp]

So what is the thickest diameter a small punch press will 'punch'? Less than 3/16" mild steel?? So a better question is, Is there some kind of rule of thumb between the relationship between tons of pressure and thickness of the work? Iam mostly intrigued by what it would do with steel.

Thanks
Glenn

In addition to what Ken stated, the general rule of thumb is to not punch (attempt) with a punch smaller than the thickness of material being punched. The best answer to the actual tonnage required would be to look at the chart. If the punch is rated at 20 tons and .250" thru .250" then anything larger based on the material thickness you could get off the chart. Of course most charts are based on a flat punch so when the punch is ground (usually larger diam.) on an angle the tonnage required changes.

I have a 20 ton ball bearing (ball screw) punch, hand operated rated at .3125" thru .250", that is limited to what I can muscle. An chance of punching anything larger isn't happening. A hydraulic press with a small punch in thicker material can results in a shattered punch. When in doubt I drill.

 

[Uglydog]

Thought I'd update you on my progress.
Below is a pic of the Carver Lab Press (10ton hydraulic) I already had.
I traded the die shoe for some supervised mill time with a local blacksmith artist.
Added a shop made stripper and a holder to hold the punch holder.
I'm punching holes!!
Note that this is clearly not a production set up....
A sincere thank all of you for the encouragement and ideas.

If anyone has any extra punches with a 1/2" shaft and/or 1.25" dies they might want to sell or trade please PM. I've already got a few. A wider selection would be nice.

Daryl
MN

 

[dennys502]

Looks good Daryl.

I used to use urethane for strippers on a single punch. Different grade for hardness depending on material thickness being punched.