Making Lyman/RCBS type top punches.

[KeithB]

Had to replenish my stock of Lyman/RCBS type top punch blanks so I thought I'd post a video of the first step. The last time we ran these we had to change tools three times for each part. With a gang tool setup that we made several years ago this time all we had to do was operate the air valve to clamp and release the part and catch the part as it was cut off.

The second step - making the other end of the punch to be a specific caliber and flat faced or cupped - is done on a manual lathe.

Here is the first step

Here is the resulting output


Here are better shots of the tool holder setup. Everything is anchored firmly in place, no tool changes. Fast and accurate.

 

[Brad]

Kinda shocked at the number of passes to turn the shank.
Is that to reduce deflection of the material? To give better surface finish?

I would have expected maybe 3 cuts

 

[KeithB]

Three passes would be about right, the extra cuts come from using a couple of macro codes - G71 and G70 - to simplify the programming. If we ran more than one batch every 3 to 5 years I would write more code to take less time. As it is we ran several hundred pieces and only had to adjust the turning tool by .0002" throughout the run to hold size. There was no perceptible wear on the grooving tool. Surface finish was great, but that's 1144 for you. When we started the run we noted the program was written back in 2011.

 

[Brad]

Makes sense to me.
If it takes more time to recode than you save the it isn’t cost effective.

 

[Ian]

Production, Baby!

Having only a manual machine is why I buy blanks and finish them to my requirements. Producing a small run of identical parts on a manual machine, even being a hobbyist, is for me the definition of drudgery.

 

[Gary]

I've got some of those from Keith several years ago. Easy to finish turn into caliber specific, thanks to Keith.

 

[Brad]

Ian, I struggle to make one identical part some days.

 

[Ian]

I can identify with that.

 

[RicinYakima]

Hate to tell you how many times it took to make a Pacific push thru rod for a bullet sizer.