how to convert a mill to cnc?

[speedhound]

Ok, so can i get a simular system for nema 34s without costing a fourtune. I do not particually want it to be very fast, so dont mind if its a bit slow.

[speedhound]

I tryed pulling on the handels and measuring the weight and at about 2" away from the centre it took 4 kilograms and at 6" it to under 1 with no load to move the table. like i said i would say it has very low friction and have used smaller mills with more friction. so dont know how much power i need?

Thanks

[Robin Hewitt]

Interesting choice of units

I calculate 1 kgf inch = 0.25 Nm or thereabouts.

4kgf at 2 inches = 8kgf inches = 2Nm
1kgf at 6 inches = 6kgf inches = 1.5Nm

Table's kind of stiff if that's at no load.

You can get more Nm out of a motor with a belt reduction but that doesn't do your top speed any favours.

Q1: Can you free the table up?
Q2: Does it matter if it's kind of slow?
Q3: Could your budget stretch to servo motors?

best

Robin

[speedhound]

Ok, i dont mind if its slow, dont think i can free up the table anymore. I dont know how much a servo system would cost, so dont know about budget. I thourght they were a lot more so dont know anything about them.

Thanks

[BillTodd]

What type of Miller?

Bill

[speedhound]

Hi, ive got a thiel 158 tollroom mill. Ive seen this kit http://www.rhonmac-cnc.co.uk/index.htm and woundered if the one with the 5.8nm steppers would be enough to power it geared down 2:1, but dont quite understand about the driver, as it appears to me that it can run 4.2 amp but the motor takes 7?

Thanks

[Zadig]

I used to have a couple of Thiel 158's, excellent machines. I remember the X axis being nice and free flowing, but the Y axis was always stiff. The Y axis is created by an overarm coming forward and backward with the spindle is attached, this all added to the weight and stiffness. Have you thought how you will get the stepper/servo drive to the Y axis? I am assuming you have a fixed table and not the XY fancy one.




Mike