Trivia - Back to the Basics of Punching

Here at The Cleveland Punch and Die Company we are dedicated to providing our customers with the highest quality customer service in the industry. Our customer service personnel, known as "The Green Team", strives to provide our customers with a friendly and courteous experience every day. Our goal is to share the knowledge we have gained over the years with each and every one of our customers.

Determining the clearance between the punch and die is one of the most common issues we face on a daily basis. Today's trivia will help to address these issues!

Question #1:
If you are punching a 5/16" round hole through 1/4" A36 mild steel, what size die should be used?
Answer:
When punching 1/4" to 1/2" thick mild steel, a 1/32" clearance should be used. In this application an 11/32" die would be appropriate.

Question #2:
If you are punching a 5/8" X 1" oblong hole through 1/4" aluminum, what size die should be used?
Answer:
The suggested clearance for aluminum is 10% of the material thickness. In this particular application the clearance would be .025" (.250" thick aluminum X .010 = .025"), making the die size .650" X 1.025". While Cleveland Punch can manufacture our customers any desired die clearance, a .025" clearance would be a specialty made item. In many instances a standard 1/32" clearance would work just fine, but may produce a slight burr on the bottom of the material being punched.

Green Team Tip: The material thickness should never exceed the punch dimension!

Question #3:
If you need to punch a square hole for a 3/4" picket, what size punch and die should be used. (Material Thickness is 3/8" stainless steel)
Answer:
The suggested punch size for this application is a 25/32" to allow the square picket to be passed through the hole once it is punched. Suggested clearance for stainless steel is 18% of material thickness. This application would call for a .067" clearance (.375" thick material X .18 = .067"). This die would also be a special item. However, a 27/32" die (.843") would work just fine.

Refer to the following charts for the suggested clearance on various materials. If you have any questions please contact our "Green Team" for assistance. We can be reached at 888-451-4342 from 7am to 6pm EST.