Or an alternative of course is to just buy all the metal parts for $599US. This is what I have to build. Kind of intimidating when I look at how much needs to be made. Baby steps I guess.Thompson and NSK did have some ‘nice’ preload able ball screws with screw brushes to prevent chips from getting in the balls.
....yup, just like eating an elephant, one bite at a time. Looking forward to how you cook each piece up....Or an alternative of course is to just buy all the metal parts for $599US. This is what I have to build. Kind of intimidating when I look at how much needs to be made. Baby steps I guess.
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John, I was just suggesting where you could buy the Ball Screw components, but . . . your time is your own, so go for it !! If you have all the tooling in your workshop.Or an alternative of course is to just buy all the metal parts for $599US. This is what I have to build. Kind of intimidating when I look at how much needs to be made. Baby steps I guess.
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Hey Len,John, I was just suggesting where you could buy the Ball Screw components, but . . . your time is your own, so go for it !! If you have all the tooling in your workshop.
I am still working on my ‘Linear Slides’, when I can get my hands on affordable material inputs.
Prioritize your efforts.Hey Len,
Thanks for the suggestions.
I had the set for my mill in my Misumi shopping basket at one point.
I've done all the CAD drawings to see what can fit and where for the ball screws. But then I got distracted with other projects like the power draw bar. Then the Knee upgrade from Stepper to AC Servo and I haven't properly finished that one mounting plate or the pulley covers.
There's no end to projects. <sad face>
Here's the X axis lead screw on the mill. Pretty ugly and explains the backlash.John, I was just suggesting where you could buy the Ball Screw components, but . . . your time is your own, so go for it !! If you have all the tooling in your workshop.
I am still working on my ‘Linear Slides’, when I can get my hands on affordable material inputs.
I've looked at the double stacked versions too. Not sure if they are worth it. Thing is right now a lot of backlashFYI - Even brand new lead screws have some backlash.
You have to learn to compensate for it.
Don’t try to TOTALLY eliminate the backlash, a leadscrew without some play (backlash) will bind and gall the threads.
The Ballscrew & Ballnut will also have a small amount of backlash.
The solution is to make sure you adjust for it during operation's.
OMG. +/-0.0004 in my dreams...I recently replaced the leadscrews with ballscrews on my 8x30 knee, was a bit easier than I expected.
A few FYI that might be useful:
- Mocking up with 3D models sped up the process.
- IIRC the Y nut (and for sure the leadscrews) can be removed with the X-table still on and at one extreme (although the extended table should be supported)
- The cheap ballscrews I used (eBay e-convenience) did have some backlash just less than the original leadscrew, I tweaked them for less. I also had some slop in the bearings and reduced that to near zero with matched angular contact bearings, the super cheap non matched angular contact bearings on Amazon etc are complete junk, don't waste the few dollars they sell them for.
- When adding the ballscrews to your one-shot oil distribution, be aware more than necessary oil will flow through the ballscrews, so you might want to add a restrictor(s)
- Looks like you have modeled most of what you need, but if you want any of my step models just ask and I will send them your way.
It is nice to have a machine that goes exactly where it is told to go. +/-0.0004"
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That is a pretty high degree of accuracyOMG. +/-0.0004 in my dreams...
I won't pretend to have any expertise in this area. My comment is based on the value displayed on the linear scales.That is a pretty high degree of accuracy
When we were inspection ground and lapped parts at Ex-Cell-O we would have stacked gauge blocks with a dial indicator on a marble table to verify those dimensions.
Maybe @slow-poke can provide some examples of his work.
Well a different approach I think to the tapered pattern is to do a bit more at the front end. I'm trying to create this part which is 3.5" diameter and the small bore is 2.5". Two tapered roller bearings fit in either end.Or an alternative of course is to just buy all the metal parts for $599US. This is what I have to build. Kind of intimidating when I look at how much needs to be made. Baby steps I guess.
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