CactusChip
06-30-2003, 11:12 AM
Hi all,
I've been asking in a few places about this little mill/drill machine (with some very good responses), and thought I'd check here, too.
I bought my machine when it was on sale for around $260, so I thought it would work out well for my first CNC. After polishing the dovetails and counterweighting the head via a pulley and weight, I can move the x,y, and z screws fairly easily. I ordered some timing pulleys to provide a 3:1 reduction of my 150 oz-in steppers (5V, 1.4A). I'm now pumping in 24V with current limiting power resistors. However, I'm still worried that I might miss some steps when working with hardened aluminum or somewhat "sticky" delrin.
Has anyone upgraded this little machine to ballscrews? I priced some 5/8 screws and nuts at Mcmaster, and think I can upgrade for less than $150 (of course I'd have to buy another $90 set of pulleys to clamp to the large diameter screws). I have not worked with ballscrews before, but have seen them mentioned in many places. Do they make that big of a difference in backlash and the torque required to push the beds?
Does anyone have any other friction reducing hints? Is there a way to mount a row of bearings on the contacting surfaces of the dovetail slides? I've seen linear bearing type things designed to roll over rods, but I don't think there is enough room to replace the dovetails with rods and the bearings.
Thanks for any tips. I'd love to make this a nice little machine for my desktop, especially at the low prices I've paid for the machine and motors.
Billy Byler
I've been asking in a few places about this little mill/drill machine (with some very good responses), and thought I'd check here, too.
I bought my machine when it was on sale for around $260, so I thought it would work out well for my first CNC. After polishing the dovetails and counterweighting the head via a pulley and weight, I can move the x,y, and z screws fairly easily. I ordered some timing pulleys to provide a 3:1 reduction of my 150 oz-in steppers (5V, 1.4A). I'm now pumping in 24V with current limiting power resistors. However, I'm still worried that I might miss some steps when working with hardened aluminum or somewhat "sticky" delrin.
Has anyone upgraded this little machine to ballscrews? I priced some 5/8 screws and nuts at Mcmaster, and think I can upgrade for less than $150 (of course I'd have to buy another $90 set of pulleys to clamp to the large diameter screws). I have not worked with ballscrews before, but have seen them mentioned in many places. Do they make that big of a difference in backlash and the torque required to push the beds?
Does anyone have any other friction reducing hints? Is there a way to mount a row of bearings on the contacting surfaces of the dovetail slides? I've seen linear bearing type things designed to roll over rods, but I don't think there is enough room to replace the dovetails with rods and the bearings.
Thanks for any tips. I'd love to make this a nice little machine for my desktop, especially at the low prices I've paid for the machine and motors.
Billy Byler