This prompted me to design my own hollow square punch – not only because I needed a 3/16” size, but also one that is specifically designed to be hand held.
My early attempts did not meet expectations, but after a few tries, the new tool was actually outperforming expectations. Dozens of these were machined and made for me, by my friend Bob Hadley. Thanks BOB!
Once I had a working tool in hand, I submitted the idea to Lee Valley Tools. They liked it and turned it over to their R&D department. The Lee Valley folks made improvements and sent me the prototypes for testing. My friend George Knutson helped me run the punches through their paces. I then returned them along with comments and suggestions. We went through this process twice. I was greatly impressed with the Lee Valley R&D people – they really brought the tool to perfection!
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Later this month Lee Valley Tools will have available for purchase the hollow square punches in six sizes -3/16” - ¼” - 5/16” - 3/8” 7/16” - ½”.
Use the product code 50K5920 to check on the punches availability.
I will follow up soon with a blog that details the use of the punches.