# Better Acme Screws for the G0704



## OakRidgeGuy (Oct 11, 2012)

Just being curious if anyone has a lead on where I can get some better acme X & Y screws and nuts for the G0704 that I am fixing to order. I don't plan on making this machine a CNC machine, but will install a good DRO kit on the machine. I want to reduce the backlash and I figure that while I have the machine torn down for cleaning, it would be a good time to install the new screws and nuts. I read on another forum about Kerk screws, but I have no idea of the cost. Any other options?


----------



## Rbeckett (Oct 11, 2012)

ORG,
The difference in Acme screws and ball screw is not really large.  I would opt for ball screws to eliminate most or all backlash for your DRO set up.  Jumps4 will definately have a decent supplier and will know how to get what you need.  I'll make him aware of this thread and see if we can't get you fixed up nicely. 
Bob


----------



## 7HC (Oct 11, 2012)

OakRidgeGuy said:


> Just being curious if anyone has a lead on where I can get some better acme X & Y screws and nuts for the G0704 that I am fixing to order. I don't plan on making this machine a CNC machine, but will install a good DRO kit on the machine. I want to reduce the backlash and I figure that while I have the machine torn down for cleaning, it would be a good time to install the new screws and nuts. I read on another forum about Kerk screws, but I have no idea of the cost. Any other options?



I think I'd wait until it arrives before worrying about changing the screws.  Those mills have a good reputation for quality and once you you fit DROs to the X and Y (you will already have one on the Z), it'll be easy to compensate for any backlash that can't be adjusted out.

Backlash will be more of a problem if you go to CNC.  With the DROs you can position and re-position the workpiece accurately by hand every time.


M


----------



## OakRidgeGuy (Oct 11, 2012)

Mr Beckett, 

The problem with ballscrews is that you may pull the tool into the work pcs because of the lighter tension of the ballscrew from what I understand, so hence I was wondering about the acme screw. 

7HC, 

Thank you for your input, I think that I am planning ahead more than anything. I will be indeed wondering just how good it will be. I had found a good deal on a Mitutoyo DRO, but after going back and rechecking the specs. The Y axis scale is too long for mounting. But for 499 vs 1099 it was at a great price. dang it.


----------



## jumps4 (Oct 11, 2012)

I would not put ballscrews on a manual mill because there is not enough friction to keep them from turning on their own if you forget to lock an axis. and if i understand you correctly you are buying a new machine? if so i just converted a new zx45 to cnc and the screws and nuts i removed to install ball screws where really nice and well fit. there was a backlash adjustment on the nut and the preload on the thrust bearings was adjustable. if i was not converting to cnc i'm sure they would have outlived me with proper lubrication and cleaning.they were also imperial screws not metric screws with imperial dials. your machine may be just as good.
if your still wanting to buy better acme screws and nuts you can try mcmastercarr.com they have precision acme screws and nuts.
I hope that helps
steve


----------



## OakRidgeGuy (Oct 11, 2012)

Thanks Steve for the input, I will keep that in mind. I know that sometimes, I can get my head before my donkey. But either way, it is still a learning experience and there is never a stupid question! 

Doc


----------

