These are my 4pc Slot Punch Sets for THIN Material
These slot punches are made from new 5160 spring steel and there are four sizes included in this set.
3/8-inch
1/2-inch
5/8-inch
3/4-inch
Each punch is made from 5/8-inch diameter steel and is about 9-inches long!
These flat slot punches are used for punching a rectangular hole in stock that is 3/8-inch or thinner. Slot punches are most often used along with an opener and drift to make a round or square hole for mortise and tenon joinery, bottle openers, pass-through, and other common blacksmithing operations.
To use these punches, place them on the stock where you wish to punch, hit once, remove the punch, inspect the mark you made, place the punch back on the mark, strike again. Repeat this process, removing the punch from the hole between EVERY hammer blow, until you have punched about 75% of the way through the stock. Flip the stock over and finish punching from that side.
Removing the punch between every hammer blow allows you to inspect the hole you are making and make any adjustments to keep the hole straight and centered. It also keeps the punch from overheating and then deforming. You may also use an oil-based coolant to keep your punch from overheating. DO NOT use a water coolant.
When used correctly, these punches will provide dependable, long-lasting service. Occasionally redressing the bevels will be necessary.
I use these punches every day for punching holes in mild and high carbon alloy steels.