Hi all,
I have recently got a shaper in my H/ws, one of the projects I would like to do is a t slotted cross slide for my 10" lathe.
Im a bit puzzled as to how to make a tool to cut the bottom of the T, ie the undercut section of the T, Ive searched here and on some groups but not hit anything yet,
Any Ideas?
Lee
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Seems to me that whatever approach is used in cutting internal keyways (somewhat modified) is what you are looking for.
Ken.
It's just what you'd think, L-shaped, actually one right- and one left-handed. The books I have recommend locking the clapper block in use. Slot the center first, then work out the sides with the tools. The older books showed how to forge the tools. Sounded like a lot of work, so I found other ways to fabricate T-slots. If you're just cleaning up cored castings, that's different.
Stan
I've never tried this, but, since I have a shaper, I've paid attention to what various people have said on the subject.
Obviously, when the clapper block swings, it will bind the tool and something (probably the end of the tool...) will snap. You can lock the block, but the tool won't stay sharp for long. On some shapers, you can rotate the clapper block 90 degrees. Or you can make a block with a vertical axis. I heard of one fellow improvising one out of a door hinge!
The easy way, if the shaper is big enough and the work is small enough is to cut the center, then mount the work on edge and put a boring bar (smaller than the center slot) in the shaper and cut the edges like you would a keyway.
To line up the work, mount a dial indicator on the ram and turn the machine over by hand. You can indicate off the bottom of the center slot, if nothing else.
Jerry
You'd be far better served to use a Woodruff cutter in a mill in this instance. If you don't have that capability, it can be done with offset tools, but it will be somewhat challenging to accomplish without screwing up something along the way. If you stay with the shaper, pay attention to the clapper so it can't bind on the return stroke.
I assume your cross slide is cast gray iron. Luckily, it machines quite freely, which will help tremendously, regardless of the method chosen.
Good luck!
Harold
I'm working from memory here but IRRC teenut posted a way of doing this with the clapper loose. What I recall is that a spring strip is bent and attached to the clapper in such a way that the tool is pulled completely clear of the slot on the return stroke.
Wayne Cook Shamrock, TX
The door hinge method is to use a cut down hinge as a secondary clapper so that the tee slot cutter rides forward on the cut, then the hinge overrides the work. When the stroke returns, the hinge flops down and prevents the cutter from hanging on the work. I have, somewhere in my boxed up stuff, a shaper "jobs" book that describes the process and has pictures. It will, sadly, be a while till I can get the boxes unpacked.
To modify the hinge, skinny up the long strap to fit under the tool holder, with the wide side on the other side of the hinge line being the toolsaver portion.
The cutter is just an L shaped cutter with reliefs on any side that might rub, which is just about all of them.
Cheers Trevor Jones
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