[cmaas]

I have been given an ex-Boeing 3 axis fabric cutter. I'd like to convert the machine to a router for wood, foam and, maybe, light aluminum cutting if the machine is up to it.

The table size is about 6'x6'.

Other than the servos none of the electronics were included. As I'm not very tech savvy rather than try to figure out how to get the servos operational I'm thinking of converting to steppers. Buying the 650oz-in stepper motors and electronics package from Buildyourcnc.com appeals to me but I am not sure how to figure out if those motors are the right choice.

The 500 watt servo motor runs the y axis with a 6:1 reduction and the 300w runs the x with a 3:1 reduction.

I'll build a new z axis. With that the gantry should weigh about 100lbs.

Can any one tell me if those 650oz-in steppers are adequate to take the place of the current servos? Thanks!

Here are some pictures of the servos and gantry:

[doorknob]

I have no direct experience in this area, so feel free to ignore what I say about it.

However my understanding is that typical servo motors are generally run at higher speeds (rpm) than stepper motors, which is why you will often see reduction gearing on servo motors, but not as frequently with stepper motors. So, neglecting torque discussions for the moment, you may find that axis speed is a concern that you should investigate.

[Al_The_Man]

My choice would definitely stick with the existing servo's, they are nice DC servo's so if you can detect the type and resolution of the encoders, you should have no problem finding drives.
Al.

[Marti]

I'm curious about the fabric cutter - I've been trying to figure out how to add a cutter wheel to the machine I am planning on building.

[cmaas]

Thanks for the thoughts guys.

I can reconfigure the belt pulleys to get the ratios closer to 1:1 if necessary.

I am really tempted to use those nice servos but I am worried about how expensive, time consuming and just plain beyond my capabilities piecing together that system might be. I am new to this CNC stuff an having been exposed to the chemicals used in composite boat building for 40 years doesn't seem to have made me any smarter!

I can't help with the cutter configuration. That whole set up was gone when I got the machine. I do know that it was some sort of reciprocating knife designed to cut stacks (like maybe 1"?) of pre-impregnated composite fabric. The machine also had a vacuum table made of plastic bristle. It's actually a really cool machine, very well made. The gantry is a carbon fiber box beam.

[Marti]

Thanks for the thoughts guys.

I can reconfigure the belt pulleys to get the ratios closer to 1:1 if necessary.

I am really tempted to use those nice servos but I am worried about how expensive, time consuming and just plain beyond my capabilities piecing together that system might be. I am new to this CNC stuff an having been exposed to the chemicals used in composite boat building for 40 years doesn't seem to have made me any smarter!

I can't help with the cutter configuration. That whole set up was gone when I got the machine. I do know that it was some sort of reciprocating knife designed to cut stacks (like maybe 1"?) of pre-impregnated composite fabric. The machine also had a vacuum table made of plastic bristle. It's actually a really cool machine, very well made. The gantry is a carbon fiber box beam.

thanks. You'd think it would be easy to find info on where to find cutters and knives and how to assemble them, but I'm not having any luck

[Bl@ckrat]

hi

did you ever convert this machine ?