[erikjgreen]

Greetings, all;


I'm planning to build a wood router table to sit next to the milling machine in my shop, and I'm doing some designing and collecting of useful parts.

I'd like to recycle and use the gantry I took off an old CMM system last week, since it's rather nice. It's made of steel tubing with some reinforcement, all welded. It's about three and a half feet wide and two feet high, which I want to put on a 6 foot table. It's in three pieces and bolts together with socket head cap screws through flanges.

I'm wondering about weight... the gantry weighs about 100 lbs empty, and I'll have to bolt on carriages, a drive mechanism, the Y/Z system, and the spindle, so probably something like 150-ish pounds when done.

It is really solid, rigid, and precision formed so I can basically skip gantry design and construction, plus it should be capable of handling a lot of force.

I'm planning on using a set of 5 phase steppers, 697 oz/in, for this machine. I'm suspecting I'd have to use a pair of them locked in step to move the gantry to avoid any racking. Or could I get by with one?

Probably the X axis would be geared 4:1 to move the gantry with belts.

Your thoughts?

Erik

[Mountaincraft]

The Mechmate Gantrys are heavier than that with similar sized NEMA 34 motors.. They use a R&P drive with two motors on the X... I think most builders use a 3:1 ratio..

I would imagine my Gantry weighs in that neighborhood too.. It's 6 feet wide on an 8 foot long table... I use dual 906oz NEMA34's with a R&P drive at 2:1... It flies... I've taken it up to 1200IPM Rapids and it didn't even blink.. I haven't tried faster....

I am currently running the table from 300-400 IPM while I work out the kinks... Fastest I've cut at so far has been 300 IPM...

[CarveOne]

I have a 5' x 12' homebuilt machine with 3:1 R&P drives on X and Y driven by four 495 oz NEMA 23 steppers, G203v drivers, and 72vdc PSU. X is dual drives slaved in Mach3. My gantry is 185 pounds and can jog at 1,400 ipm. I run accel at 30 to 40 and haven't snapped a motor shaft yet.

I have had racking problems, but it was a Mach3 settings issue that was resolved and no problems with racking since then.

You should have no problem with power or racking.

CarveOne