Magnetic slide of Z-axis

[Constantine]

Hi fellows, I'm new here.
I've checked some of your threads, and could probably contribute a bit.

The machine was designed for wood, plastic, soft metalls,
working envelope 200*230*65mm

fancy solution (miiiinnnneee :) ))) of Z-axis - neodymium magnets + Teflon as the slides and polished metal plate. the force required to tear it off - 20kg, to slide it - 2 kg, works pretty fine, no backlash at all ;) .

a bit of history in pictures, + work done so far.

X, Y axis - built using hardened 300mm D=12mm Thompson rods,
linear ball bearings, plastic bushings,
tools used for the build - lathe, milling machine, drilling machine, digital calliper, common sense.

[BillTodd]

Z-axis - neodymium magnets + Teflon as the slides and polished metal plate.

Great idea (although be careful not to generate any steel or magnetic swarf)

I wonder if it'd be possible to build a roller/ball slide using a similar technique???

[Constantine]

yes, it would be not a problem, but we would loose the main advantage - Simplicity:)

Any way lets say that we use at least 10kg*cm motors and screws of about 4mm pitch - that means a reduction from 2*Pi*1cm to 0.4cm = 15 - which means for a perfect screw you'd have a 150kg moment of force, those 2kg required for friction will simply disappear.

I'd place roller and magnet only where you need taking off and placing back the carriages.
Oh - by the way my Mark 1 machine was MDF based router. I've made them like that:

[Smiler]

Looks like you have quite a bit of chatter going on from the looks of the engraving, too much unsupported railage. Totally mad and wonderful idea tho, love it.

Jeff.

[Constantine]

well - that was 140 grams valentine greeting. Sad that this is now my Ex GF.

but as Italians say never run for a train or a woman, next one always come.

you haven't seen one Russian fellow' wooden CNC :)))) if you think that my idea is crazy :)