C&P crank throw

On a mid-size C&P old-style, I’m looking for-

the crank throw (distance between centers of main and offset shafts)
diameter of the offset shaft
I think the main shaft is 1.5”(yes?)

I think the throw is around 2” but I can’t get near one to measure anytime soon.


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do you plan on trying to make one? roughly measuring, my 14 x 22 shaft seems close to 2 “. Maybe 1.75”. the 12 x and 14x are probably the same shaft

The 8x12 and 10x15 apparently used the same casting for the treadle-cranks shafts, then turned the straight bits to size for each model. A machinist friend once successfully turned a 10x15 to fit an 8x12. No idea if larger sizes have size similarities.

Yes, making one. I have the shaft size, I need the offset from the main shaft to the crank part (where the drop to the treadle connects). It probably doesn’t matter the exact size, but I’d like to be similar.

without bearings to support the center, you will need a very good welder.

Good thing we have one. We have the capability of casting the entirely piece in iron but it’s a lot easier to fabricate than make the pattern (and we already have the necessary metal on the rack or in the scrap pile). Heck, I think we fab’d the existing straight shaft in the press.

The only thing we’re missing is some dimensions, and they’re not really that critical (a photo showing the crank and a ruler would do for this).

your going to need to find a very good welder. Trying to bolt together the “throw” won’t work long.

As I already said, we _have_ a very good welder, don’t need to look for one. (Who said anything about bolts? I know that won’t work well unless the parts are machine-keyed together. Welding is easier and faster.)

Still doesn’t answer the question.

if it’s for a treadle, go 2 in throw.