Ball Screw Pitch

This forum is dedicated to those Hobbyists Interested in CNC machining in their home shops. (Digital Read Outs are also topical, as is CAD/CAM as it relates to CNC)

Moderator: Harold_V

ed92254
Posts: 3
Joined: Thu Nov 16, 2017 10:55 am

Ball Screw Pitch

Postby ed92254 » Thu Nov 16, 2017 11:05 am

Setting up a lathe for CNC and was wondering if ball screw pitch can be different between the Z axis (5MM) and X axis (4MM). Had to get a smaller ball screw for my X to physically make it fit and found out it was 4MM pitch.

User avatar
ctwo
Posts: 2510
Joined: Tue Mar 27, 2012 12:37 pm
Location: Silly Cone Valley

Re: Ball Screw Pitch

Postby ctwo » Thu Nov 16, 2017 11:10 am

I believe this would be addressed in your controller software - which one are you using?.
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
Disclaimer: I'm just a guy with a few machines...

ed92254
Posts: 3
Joined: Thu Nov 16, 2017 10:55 am

Re: Ball Screw Pitch

Postby ed92254 » Thu Nov 16, 2017 11:16 am

Mach 3

User avatar
Dave_C
Posts: 868
Joined: Mon Apr 21, 2008 10:34 am
Location: Springfield. MO.

Re: Ball Screw Pitch

Postby Dave_C » Fri Nov 17, 2017 1:16 pm

Yes, Mach 3 will let you set up each axis with different leads or different motors. It is calculated in the turns per inch entry if your are using imperial setups. If you are setting up a metric setup it wants distance of travel per one turn of the motor.

So a .200" lead would be 5 tuns per inch and so on. You can use metric ball screws and still set up your machine as "inches" but you'll have to do some extra math.

Dave C.
I learn something new every day! Problem is I forget two.

User avatar
SteveHGraham
Posts: 6563
Joined: Sat Jan 17, 2009 7:55 pm
Location: Florida

Re: Ball Screw Pitch

Postby SteveHGraham » Fri Nov 17, 2017 2:01 pm

Wow. A CNC question I could have answered.
Don't trigger me, bro!

ed92254
Posts: 3
Joined: Thu Nov 16, 2017 10:55 am

Re: Ball Screw Pitch

Postby ed92254 » Fri Nov 17, 2017 5:02 pm

Thanks for the help guys its been a fun build so far and sorry if I ask some scary questions?? lol

dash9
Posts: 49
Joined: Mon Oct 09, 2017 9:02 pm
Location: Barnesville , PA
Contact:

Re: Ball Screw Pitch

Postby dash9 » Mon Nov 20, 2017 9:13 am

Sling Mach 3 out get the Centroid Acorn.

http://www.centroidcnc.com/centroid_diy ... oller.html

User avatar
Dave_C
Posts: 868
Joined: Mon Apr 21, 2008 10:34 am
Location: Springfield. MO.

Re: Ball Screw Pitch

Postby Dave_C » Mon Nov 20, 2017 4:38 pm

I'd second that, even though I am still running a Mach 3 lathe conversion. Centroid is Funac compatible and runs a full set of G-codes while Mach 3 runs a partial set and is not compatible with anything else, as far as I'm aware. You will need a spindle encoder, a real one and not just the indexing type like mach uses, if you want to thread or do rigid tapping with the Acron/Centroid setup.

I'm in the process of reading the entire manual right now for the Centroid lathe and mill software. It is written very well, more like the way I understand tech manuals.

Dave C.
I learn something new every day! Problem is I forget two.

User avatar
Bill Shields
Posts: 4803
Joined: Fri Dec 21, 2007 4:57 am
Location: Somewhere in the World
Contact:

Re: Ball Screw Pitch

Postby Bill Shields » Mon Nov 20, 2017 9:05 pm

actually you want an encoder WITH a zero pulse index point so that you can reliably find home every time.

User avatar
Dave_C
Posts: 868
Joined: Mon Apr 21, 2008 10:34 am
Location: Springfield. MO.

Re: Ball Screw Pitch

Postby Dave_C » Mon Nov 20, 2017 10:02 pm

Ok, My poor explanation! Mach 3 uses a single slot spindle index and nothing else. So basically you make a disc with one slot in it, use an optical reader to read the slot or you can use one of those other type single pulse per rev encoders like a photo tac.

Mach 3 can't read a real 2000 line encoder for spindle positioning. Mach 3 also can't use CSS and FPR at the same time. (constant surface speed and Feed per Rev) One or the other but not both!

So no rigid tapping!

Dave C.
I learn something new every day! Problem is I forget two.

User avatar
ctwo
Posts: 2510
Joined: Tue Mar 27, 2012 12:37 pm
Location: Silly Cone Valley

Re: Ball Screw Pitch

Postby ctwo » Tue Nov 21, 2017 6:09 am

I'd have to spring for the Centroid Pro CNC. Looks like an interesting solution.
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
Disclaimer: I'm just a guy with a few machines...

User avatar
Marty_Escarcega
Site Admin
Posts: 1689
Joined: Wed Dec 18, 2002 8:17 pm
Location: Mesa, AZ USA
Contact:

Re: Ball Screw Pitch

Postby Marty_Escarcega » Wed Dec 13, 2017 7:39 pm

ctwo wrote:I'd have to spring for the Centroid Pro CNC. Looks like an interesting solution.


You WON'T be dissappointed!
Marty
"Jack of all Trades, Master of None"


Return to “Home Shop CNC”

Who is online

Users browsing this forum: No registered users and 3 guests