I have a 2.5mm pitch ballscrew and I need to set up the overall turns ratio in the wizard. How do I set up a units equation to convert a metric screw pitch to one in inches?
I have a 20 tooth gear on my motor belted to a 50 tooth gear on my ballscrew. That gives me a 2.5:1 gear ratio (50/20). So my initial overall turn ratio should be 2.5*ballscrew pitch.... I did some incorrect assumptions and made the ballscrew pitch just a simple mm to inch conversion (2.5mm = 0.0984252in) but that gave me a pully reduction ratio of 0.25 and some change which is extremely low. My mill axis doesn't even noticeably move with that input. I know there is the measurement method to get the overall turns ratio but I'm still on page 53 of the setup manual getting my initial numbers roughed out.
metric thread pitch to SAE question
Moderator: cnckeith
-
- Posts: 2189
- Joined: Sat Nov 18, 2017 2:32 pm
- Acorn CNC Controller: Yes
- Plasma CNC Controller: No
- AcornSix CNC Controller: Yes
- Allin1DC CNC Controller: No
- Hickory CNC Controller: No
- Oak CNC controller: No
- CNC Control System Serial Number: Acorn 238
- DC3IOB: No
- CNC12: Yes
- CNC11: No
- CPU10 or CPU7: No
- Location: Bergland, MI, USA
- Contact:
Re: metric thread pitch to SAE question
25.4 / 2.5 = 10.16 * 2.5 = 25.4
(mm per inch) / (metric pitch) = (ballscrew turns per inch) * (screw pulley) / (motor pulley) = (turns per inch)
2.5 seems awful fine for a ballscrew. Are you sure?
(mm per inch) / (metric pitch) = (ballscrew turns per inch) * (screw pulley) / (motor pulley) = (turns per inch)
2.5 seems awful fine for a ballscrew. Are you sure?
-
- Posts: 51
- Joined: Tue Sep 29, 2020 10:00 pm
- Acorn CNC Controller: Yes
- Allin1DC CNC Controller: No
- Oak CNC controller: No
- CNC Control System Serial Number: none
- DC3IOB: No
- CNC12: Yes
- CNC11: No
- CPU10 or CPU7: No
Re: metric thread pitch to SAE question
Thank you! Now that I see it I feel a little dumb for not initially knowing how to do the conversion lol. I guess I'm not 100% positive it's a 2.5mm pitch ballscrew, the companies out of business and I got that info from a very knowlegble ex-employee. Now that you have me questioning it I'll measure a rough estimate tomorrow to see if its close.
-
- Posts: 7327
- Joined: Wed Mar 03, 2010 4:23 pm
- Acorn CNC Controller: Yes
- Allin1DC CNC Controller: Yes
- Oak CNC controller: Yes
- CNC Control System Serial Number: none
- DC3IOB: Yes
- CNC11: Yes
- CPU10 or CPU7: Yes
- Contact:
Re: metric thread pitch to SAE question
turn the screw one revolution and measure how far the axis moves.
what type of machine is this on?
common milling machine metric pitches are 5 and 10
router 20 for XY and 5 for Z
related reading.
https://centroidcncforum.com/viewtopic.php?f=63&t=1801
and please always post a fresh report.zip when requesting support.
what type of machine is this on?
common milling machine metric pitches are 5 and 10
router 20 for XY and 5 for Z
related reading.
https://centroidcncforum.com/viewtopic.php?f=63&t=1801
and please always post a fresh report.zip when requesting support.
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html