Question: I am attempting the oft-mentioned but apparently seldom-documented Taig headstock to 4th axis conversion. I have chosen to use an anti-backlash worm gear at 64 pitch, with 140 teeth, for a 140:1 reduction and 56000 steps/rev at half-step with a 200 steps/rev stepper, with 0 backlash! My question is, will a 64 pitch brass gear stand up to the task? Is 140:1 too ambitious? I've never built anything that takes significant torque before. I have never seen anyone use anti-backlash worm gears save for these people at 72:1, do they work well? http://www.kdntool.com/_sgt/m3m1s1_1.htm
And of course, anyone with links or information - any little bit helps!
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So, I've got a converted Taig (XYZ). Up until a little while ago, I thought I was happy, and then I saw this and thought of how completely insufficient my machine was for all the things I've never used it on before. All I can think of now are parts that require a 4th axis...:
http://members.shaw.ca/mryankey/4th%20axis.htm
I've always put away the idea of having a 4th axis since I don't have the budget for it, but I have seen 3 examples of the headstock to axis conversion (only 1 documented that I could find), and I think I can do it.
I'm ready to fire on the following parts:
$71.40 4-jaw self-centering chuck (Taig part #1060)
$60.25 Headstock & standard spindle (Taig part #100-00 or 200-60)
$6.00 Headstock mounting plate (Taig part #200-48)
$52.53 64-pitch 140-tooth Anti-backlash worm gear (SDP/SI part S1B86A-P064B140S)
$17.50 Worm (SDP/SI part S1D96Z-P064SS)
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$197.68 Total (w/o motor, versus $270 for the Sherline 3700CNC w/o motor)
I already have some pieces, but I priced them out for the benefit of those who don't. Buying your gears from Nordex instead of SDP/SI will save you ~$10, but you have to register (free) to see their prices. If you don't use anti-backlash gears you can save another ~$20, and about another ~$10 if you go down to about 72:1 ratio.
So I just have to make the NEMA 23 stepper mount (I'll post the 3d model later, nearly done) and fabricate an adapter to fit the anti-backlash worm gear (.25" bore) on the 5/8"? spindle. I can't just bore it out like a normal gear since the anti-backlash gear is composed of two halves. The worm itself is pre-bored to .25" in which is standard size for the motor so it will slip right on.
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