I built a few of these for myself, but as good news travels fast, people found out about them and wanted them. I built them with some future-proofing as best as I could see by making the foot pedal for pullrod or pushrod configuration. Also putting in ten different axle pivot positions so you can choose the leverage you want.
I had ordered an Eastwood deep throat shrinker stretcher with stand to fulfill an immediate need during the chop on Richard’s Four-door Mercury and man was I ever disappointed. It didn’t even work as shipped without modification, the pullrod was about 4 inches short of working AND it needed to be bolted to the floor. Or at least a large plate that would be a pain in the ass to move about the shop. I needed mobility and stability. So a few hours of dreaming on my Alibre’ software and I came up with a base that would meet my needs.
Postprocessed the files and CNC cut the plates out of 1/4″ steel plate and TIG welded my prototype machine together. This first unit had a solid body 3/8″ foot pedal on it and I used a clevis to connect the pullrod. I found out shortly some limitations to this design so I cut a pair of 3/16″ plates and was able to use a HEIM joint instead of the clevis. This freed up the feel and gave me the range of adjustability I needed. The arm pivots on bronze shoulder bushings and has a 3/4″ axle retained by a pair of snap rings. With every hole reamed to size, changing pivot positions was fairly easy to do. Once I found the arc and foot position that felt the most comfortable I threaded some heavy wall tube and welded on a six pointed thumbwheel. This also was changed out to a lighter setup and I added a pair of counter springs to the back of it to improve the pedal feel, it was just too light and was far to easy to over shrink the workpiece.
It didn’t take us long to put it into use…
The most recent one out the door went to our new friend Douglas, member of the Arizona Artist Blacksmiths. He had me build an adapter to work with his Lazze branded Shrinker/Stretcher. I machined an aluminum base adapter and fabricated a new upper clevis to attach to the Lazze piece. I have these on file and can produce them for your machine also.
Other than the minor updates to the foot pedal arm and the pullrod itself, the design has worked fantastic. There are 7 of them in the world now with two available right now. Hit the E-store if your interested in one.