Making a new drive block for the Scotch Yoke

[Shawn]

I recently bought a Douglas 10.5 shaper that was in pretty decent shape. The only real issue with the machine is the drive block in the Yoke seems to have either worn down or was never the correct size to begin with. When the shaper is working the drive block makes a clunk at the beginning and end of each stroke due to the gap between the block and the yoke. I would have probably just ended up living with this issue as with the amount of use any of my tools get it would probably never get worse.

A fellow member here on the forum asked me what the size of the block was and then offered up a chunk of NiBrAl, I had to do some research to even know this was an aluminum bronze alloy and pretty tough stuff. Thanks Dallen, the block arrived in the mail today. It's bigger than what I need so I will have to sort out a way to hold it in my bandsaw and see how much I can save for other projects. The generosity of professional and hobby machinists is something I have not seen anywhere else, online or in life in general.

If someone has a shaper that is in good working order and doesn't have the clunk at each end of the stroke I was hoping you could measure the gap between the block and the yoke for me. I haven't measured the gap in mine but I'll bet it's close to 1/16th of an inch.

Thanks again Dallen, the block is sitting on my desk just begin me to get into the shop.