rung fu clone RF-45 ZX45 cnc conversion

[Bernie_nor]

Re: zx45 milling machine cnc conversion

What was the size of the motors originaly?
(Nena 34 and Nema 43, but what was the torque?

parts list so far
3 motors, driver, power supplies ebay#170796217146 $896.00

The information is no longer available om Ebay.


Cheers!
Bernie

 

[jumps4]

here is a pic of the 3 axis motors I used. I purchased another motor, power supply and driver for the 4th axis.
the EBay item number is " 140906996891 " It has a nema 42, 4200 oz/in motor for the z axis and nema 34 1600 oz/in motors for the x and y. I used a nema 34 870 oz/in on my 4th axis.
steve

 

[jumps4]

also the breakout board that comes with the motors is useless, the optocouplers are too slow for any micro-stepping and speed. I used this 5 axis board, EBay item # " 280965437859 " and a UC100 usb controller from cnc4pc.com. I can run at speeds up to 200 in per minute if I wished. I keep rapids set to 100 max for safety. the 300lb Z axis headed down at the table at 200 ipm scares the heck out of me lol
steve

 

[Bernie_nor]

Thanks a Lot Jumps4!

I'm not sure when I'll be ordering the ballscrews and the motors. At the moment my liquidity is a bit low. But hopfully it'll improve in the next few weeks. Have sold a share in another project and that shuld be sufficient to finance this one. If the buyer is paying that is.

I'm planneing on using this USB interface: http://www.edingcnc.com/index.php?pagina=detail_producten&productenid=51 A friend of mine is using this on two machines. And he can help me out when I get stuck.



Bernie

 

[Bernie_nor]

Ballscrews and nuts are ordered: Will arrive before Christmas!
Total cost 156$ pluss shipping (69$). And this is with the screws machined according to my specifications.


I'm not planning on making a build thread here for my conversion. As I'm already having a build thread on a blog (in Norwegian).


Cheers!
Bernie

 

[jbolt]

Jumps4,

Very nice thread.

I'm curious how you arrived at using 16mm ballscrews for the X, Y and 20mm for the Z. I have been reading about other RF45 clone conversions and some have used 20mm on the X,Y and 24mm on the Z.

Have you counterbalanced the gear head at all? If not have you seen any wear on the Z ballscrew?

On the Z ballscrew, what bearings did you end up using? That part was not clear to me.

Thanks for taking the time to post all the information.

Jay

 

[jumps4]

hi jay
the X and Y ballscrews are 1605's because of the close opening between the y and x axis. there is not room for the 20mm ballnut without removing a lot of material from the underside of the table. I had to remove some to fit the 16mm.
The bearing I used for z is the same type as x and y except in a square block and larger.

the entire head weight is held by the screw and no lift cylinders are needed with the 4200oz/in motor. So far i have had no issues with any axis except to go back and reset bearing preload because i didn't tighten the set screws on the retaining nuts tight enough.
I use this mill almost every day for hours without any problems. backlash is running a about .002 - .003 and mach3 comp takes care of that. nothing on the mill or screws has shown any sign of wear so far. I use marine grease in the ballscrews and way oil on everything else.
One thing i did learn was to not overtighten the ways, to get everything set correct I had to loosen the ways, set my preloads and measure the backlash and write it down. then adjust each gib untill the backlash increases and then back off just untill it stays the same. any more and your not measuring backlash correctly because it included the torque required to overcome the gib tension, and it will through everything off. the table is actually snapping into the next position if too tight.
thanks for looking
steve

 

[jbolt]

Thanks Steve,

I have noticed that on the other builds with 20mm screws did have to remove material under the table. If the 16mm is working for you then it sounds like the way to go.

I take it the bearings were supplied with the ballscrew kits?

I won't have my mill for a couple weeks and then I won't be doing the conversion until after the high school robotics season ends in April.

Do you mind if I pick your brain about your low voltage setup as I get into building the controls?

Jay

 

[jumps4]

I'd be happy to help jay
start a thread in the cnc section here and i'll post any information you may need including wiring diagrams there.
using the words zx45, rf45 and cnc conversion in the title will also draw in other people to your thread who are searching the web
steve

 

[jbolt]

Ballscrews and nuts are ordered: Will arrive before Christmas!
Total cost 156$ pluss shipping (69$). And this is with the screws machined according to my specifications.


I'm not planning on making a build thread here for my conversion. As I'm already having a build thread on a blog (in Norwegian).


Cheers!
Bernie

Bernie,

What did you order and from whom? My mill is not here yet to measure and I am curious what lengths are needed for each axis.

Thanks,

Jay