Mini lathe conversion to CNC

More
31 Mar 2016 05:00 #72437 by tml
Hi all,
I have a Sherline lathe that I would like to convert from manual control to CNC. I have no real hands-on experience with CNC and am hoping that some people here could help me sort out a general plan of what to get in order to implement EMC2 software.
1. Stepper motor: I know that I would most likely use stepper motors because they are fairly inexpensive. Servomotors are great, but as a hobby for now, I don't want to invest too much. My machine will require NEMA 23 size stepper motors.
2. Hardware: Is there a specific motion controller board that you can recommend for running EMC2? There are many choices out there that honestly I don't really know where to start looking. I think I prefer to have one that can process stepper motor encoder signals as well so that it could be operated as a closed loop system.
3. Stepper motor drive: I see the Gecko brand comes up a lot. They also make a 4-axis motor controller. It looks like this controller allows you to directly connect to normal 4-wire stepper motors. I just don't know how well it works with EMC2. It doesn't support encoders connection either, so I guess there's no possibility to turn it into a closed loop system later on.

Please let me know what input you may have...

Thanks

Please Log in or Create an account to join the conversation.

More
31 Mar 2016 11:43 #72454 by Todd Zuercher
1. (and 3.) If I were building a stepper system I'd seriously consider one of the hybrid stepper setups from Leadshine.
www.ebay.com/itm/Leadshine-Closed-Loop-s...9:g:dxoAAOSwVL1V-OrR
They aren't that much more than an ordinary stepper, but are much better.

2. You don't need any motion controller boards a simple parallel port and breakout board should due. Software stepping with a parallel port should be good enough for a low speed mill. If you needed something fast (like for a wood router with speeds over 300ipm) then hardware stepping might be important.

3. Gecko drives are perfectly fine and work well with Linuxcnc, as do almost all other stepper drives. I think most stepper drivers are pretty equivalent and interchangeable. The only real questions is quality and is the drive the right size for your motor application. I think as long as you stay away from the really cheap nameless Chinese stuff you should be ok, and even those can work adequately.

Please Log in or Create an account to join the conversation.

More
31 Mar 2016 12:37 #72461 by andypugh

tml wrote: 1. Stepper motor: I know that I would most likely use stepper motors because they are fairly inexpensive. Servomotors are great, but as a hobby for now, I don't want to invest too much. My machine will require NEMA 23 size stepper motors.


On a Sherline you can probably use smaller steppers. I have NEMA23 on my 9 x 20 lathe and it works fine.

There are off-the-shelf kits from Sherline, but you probably know that: sherline.com/product/8765-cnc-ready-lathe-upgrade/
Those are much smaller than NEMA23.

Please Log in or Create an account to join the conversation.

More
02 Apr 2016 18:00 #72577 by tml
Replied by tml on topic Mini lathe conversion to CNC
Hi Todd,
The Leadshine hybrid stepper motor sounds like a good idea. With 286 oz-in I think it has more torque than what my machine needs but I'm sure they have more models to choose from.
I'm looking into breakout boards from PMDX. Would you recommend the PMDX-122?
www.pmdx.com/PMDX-122


Hi Andy,
I am using the Sherline CNC motor mounts and the mounting holes are sized for NEMA 23 stepper motors. www.sherlinedirect.com/index.cfm?fuseact...179&CFTOKEN=33914093

Please Log in or Create an account to join the conversation.

More
03 Apr 2016 02:44 #72606 by Todd Zuercher
I've had good luck with CNC4pc's C10 board ($28).

Please Log in or Create an account to join the conversation.

More
03 Apr 2016 12:07 #72620 by BigJohnT
IMHO for a nema 23 stepper system you can't beat the 5i25 7i76 with Gecko G251X stepper drivers.

JT

Please Log in or Create an account to join the conversation.

More
04 Apr 2016 16:00 #72725 by mblaszkiewicz
I had excellent results with automation technologies Inc. Hybrid stepper kit. The one I got had 2 drivers 2 hybrid stepper motors a c-10 parallel card a torrid power supply and a12v supply for the cards. I added an encoder and e stop to the kit.

Please Log in or Create an account to join the conversation.

More
10 Apr 2016 09:59 #73040 by pippin88
I'm a big fan of Leadshine digital drivers. I have DM556 and DM856. They are excellent. Available cheap on Aliexpress.

I used Mesa 7i43 (got second hand cheap) and 7i76. If I bought new, I would get 7i76E probably.

Please Log in or Create an account to join the conversation.

More
19 Sep 2016 22:58 #80644 by tml
Replied by tml on topic Mini lathe conversion to CNC
Hey all,
Firstly thanks for your help so far. I haven't come back here for a while but I'm still working on this project in my spare time. I had been learning more about steppers and servo motors and finally decided to go with some servos instead. It's probably a little overkill for such a small lathe like this, but I thought I would experiment with it :dry: Now I'm starting to think about the appropriate computer hardware and accessory for running Linux CNC. I've always used Windows computers and never tried Linux so I'm not quite really sure what to do now. Currently I'm using a HP laptop running Windows 7 that's about 3 years old, and I've been thinking if it's possible to simply convert it to Linux to get started? For CNC work, do you think it's better to get a dedicated desktop PC? If so, how do I go about choosing which one to get? Thanks again

Please Log in or Create an account to join the conversation.

More
20 Sep 2016 17:42 - 20 Sep 2016 17:43 #80679 by andypugh
Laptops often have too much power management to work well with realtime.
Also, they tend not to have PCI ports or parallel ports. LinuxCNC does not work with USB though Ethernet is an option.

I tend to use desktop motherboards, but not in a desktop case. I put them in the same box as all the other electronics.

(I just noticed. 10,000 posts. I need to get out more)
Last edit: 20 Sep 2016 17:43 by andypugh.

Please Log in or Create an account to join the conversation.

Moderators: piasdom
Time to create page: 0.099 seconds
Powered by Kunena Forum