I just had an idea today for a self-centering vise stop. I don't recall ever seeing one, so if anyone knows of any on the market please let me know.
Anyway, the idea is to center pieces of stock that are different lengths (plus or minus a couple of inches), like for making vise soft jaws. You'd want the holes centered in the length of the stock but don't really care what the exact length is. Below is a sketch of the basic idea, I hope the lines show up dark enough.
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The two large circles represent spur gears with the teeth engaged (as one turns, the other turns the opposite direction). There can be replaceable arms of different shapes and lengths, for different ranges of stock lengths. The arms also have rollers on the ends. The unit would be mounted to a block with a couple of dowel pins protruding out the bottom that slip-fit in holes in another block that screws to the the back of your Kurt. The arms can be tied together with a spring. You basically put the stock in the vise and let the spring loaded arms rest against the ends of the stock which will center it. Tighten the vise, remove the stop unit, then mill or drill away. I thought "Equa-Stop" might be a cute name.
You know I would happily pay for a drawing of your triceratop lathe soft jaw measuring tool, if you were so inclined to sketch one up. I cannot believe how time consuming it is to re-set lathe soft jaws, and have never come up with a trick way to measure them.
Even better, I would model up a set of detailed fab drawings if you were properly motivated to make me a real one.
Looks like a good idea, it could centralize the work quite well.
What would happen if you got rid of the gears and placed a centrally pivoted vertical member in the centre with a tie rod from either end to the ends of your L shaped members. If this was practical to use it would perhaps save on a couple of gears etc.
mmm, must be me I thought mammaries rather than triceratops :)
Recall the old (and maybe not so old) three-hole punches for paper going into 3-ring binders. These do the exact same thing. I got one right here. If there were a god, you might even be able to cannibalize one of these punches to kluge sumpn up--hollow out the back jaw and stick this in there. Such a thing doesn't have to be very strong.
Have you thought along the lines of a double rack and pinion?
I did a quick search but couldn't find an example. However this one might give you an idea of the mechanism I am thinking of, look at figure items 5 & 9.
snipped-for-privacy@aol.com wrote in news: snipped-for-privacy@4ax.com:
Look at a Schunk PSH-22 gripper for that mechanism. You can buy just the rods and brass gears from them as "repair parts"...they are proud of them though.
You just reminded me of tooling we occasionally make for a window frame manufacturer. It uses a double rack and pinion to locate the hardware for various sizes of window frames.
Yeah, right after PV mentioned 3 ring binder hole punches. I think it would be a much better idea than large gears since the stop rods could move parallel to the vise jaw, wouldn't need roller tips, and could be more adjustable over a wider range.
Thanks. With a modification to using a double rack & pinion the basic self-centering idea would probably work better and be easier to make.
I drew it up in AutoCad about a decade ago, as an exercise when I was learning AutoCad solids. But it wasn't dimensioned, so would probably be useless for any manufacturing purpose.
I don't think the Triceratops would help you much in that situation. If you put the first jaw in wrong, all the Triceratops would probably do is help align the other jaws to to the first one. But when you turned on the lathe it would still wobble like a dog's wagging tail.
The laser pointer looked like a much easier to use idea. You could probably get a cheap Radio Shack laser pointer and make your own block to hold it in a mag base.
Properly motivated? LOL THAT's not likely to happen. Making ONE would probably take 30-40 hours, what with scouring surplus stores for gears, bearings, etc. and milling the parts. Even making them in quantity would be a nightmare, too many areas where close tolerances are necessary (to have any degree of accuracy) to be able to sell them at a reasonable price.
And even then it's a "feel" kind of thing (like using telescoping gages rather than a dialbore gage). You're certainly not going to measure your bores to tenths.
We could use one next week when someone will probably setup for a run of soft jaws. I would suppose our shop could use something like this about once every two or three months. Certainly not often enough for ME to go in on one of my days off to make one. LOL
I've got a notebook with little tooling projects I though of that could be useful. Maybe I'll make some of them on my Sherline when I retire in 10 or 15 years.
Dan: Actually I bought a CNC Sherline about 8 or 9 years ago. It's been in my closet ever since. I just haven't had time to play with it yet. Give me time though. LOL
HeHe... when I was how much effort you must have put into it, and I surmise while on the clock to boot,I thought, no way I will ever make one for myself, and if someone else were to to do it for profit, I would never be able to justify the cost...
The laser pointer only helps with getting all three jaws right, which is pretty simple, usually. What I am always after is, is the the ID bore close enough to what I need, or do I need to go one set of jaw-teeth more... I've thought about making a set of stepped plugs. simple enough since the ranges I am usually working with are fairly small anyway... but motivating you into another one was worth the try....oh well.
Not how I see it. Suggest you and your lover Cliff Huprich take a break from blowing each other and actually view the video of that laser pointer. Looks to me like you missed the obvious once again...sort of like upgrading Mastercam V9 to X2MR2 is a no brainer but is beyond your grasp.
I don't completely understand your wording, but I made my Triceratops (the only one in existence, as far as I know), on my own time.
I made some boring rings in three sizes, like the following:
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But that was for manual chucks where you can tell when you're overtightening. A hydraulic chuck might over-stress them before you find the right setting.
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