mdr
Active member
Hi.
I've got an older Inca planer for which I've lost the platen raise/lower crank (swept up with some chips I think.) The original crank was a bored crank handle with a hollow shaft pinned to the handle. The hollow shaft had a square broach (female) to receive the complementary square head platen raising shaft. Platen shaft head is 6mm square. The crank assembly has to be removable.
I'm currently using an adjustable tap handle to drive the platen shaft. Works OK, but difficult to move with any speed and chuck loosens too easily.
Purchased a 6mm tap socket, but the bore before the square broach was too tight to fit the shaft shoulder. I don't have the tools to accurately bore the hardened tap socket to allow it to fit.
I've tried 12 point sockets with a ratchet, but 6,7 are too tight, and an 8 too loose. I believe english sizing also won't fit - there's not enough purchase on a 12 point unless the fit is perfect.
I tried my favorite handle supply, reidsupply, but came up empty. There are handles with 6mm sq broaches, but there is no height or standoff in the bushing, so I have clearance issues.
The only other solution I can come up with is a kludge. square head shaft -> inverted 1/4" drive 1/4" socket -> hex bar stock (1/4") -> 1/4" socket -> 1/4" drive ratchet. Shapes fit, but there is noticeable slop between the 6mm square shaft and the inverted 1/4" socket drive.
Any other ideas? Anyone ever seen metric broached tubing stock?
I've got an older Inca planer for which I've lost the platen raise/lower crank (swept up with some chips I think.) The original crank was a bored crank handle with a hollow shaft pinned to the handle. The hollow shaft had a square broach (female) to receive the complementary square head platen raising shaft. Platen shaft head is 6mm square. The crank assembly has to be removable.
I'm currently using an adjustable tap handle to drive the platen shaft. Works OK, but difficult to move with any speed and chuck loosens too easily.
Purchased a 6mm tap socket, but the bore before the square broach was too tight to fit the shaft shoulder. I don't have the tools to accurately bore the hardened tap socket to allow it to fit.
I've tried 12 point sockets with a ratchet, but 6,7 are too tight, and an 8 too loose. I believe english sizing also won't fit - there's not enough purchase on a 12 point unless the fit is perfect.
I tried my favorite handle supply, reidsupply, but came up empty. There are handles with 6mm sq broaches, but there is no height or standoff in the bushing, so I have clearance issues.
The only other solution I can come up with is a kludge. square head shaft -> inverted 1/4" drive 1/4" socket -> hex bar stock (1/4") -> 1/4" socket -> 1/4" drive ratchet. Shapes fit, but there is noticeable slop between the 6mm square shaft and the inverted 1/4" socket drive.
Any other ideas? Anyone ever seen metric broached tubing stock?