Messages

1

General Mach Discussion / Re: 4th Axis PID

« on: November 22, 2016, 07:27:04 AM »

I've just come across this which seems very interesting and may be a way of having a closed loop system that is cost effective.
http://elm-chan.org/works/smc/report_e.html

2

General Mach Discussion / Re: 4th Axis PID

« on: November 22, 2016, 05:06:03 AM »

I forgot to add also that I would like to use this as a turning centre also with threading capability. This is the reason for a dc motor so I can get the rpm and torque required without to much loss in torque or rpm with gear reduction or increase.

3

General Mach Discussion / 4th Axis PID

« on: November 22, 2016, 04:13:06 AM »

Hi all, firstly I'd like to say hello as this is my first post, also thank you for all the help you have provided with me building my DIY cnc router/mill.

I have an idea for a project as we all usually do. I apologise in advance if this has been covered before. I can't find a relevant thread, if there is one I would be great full for a link.

Ok, so my idea which isn't new is to create a 4th axis with a dc motor with a encoder attached via a belt or gear arrangement. Something like this;
http://uk.rs-online.com/web/p/rotary-encoders/9189086/

So my thoughts are if I get a nice big dc motor and have control over position using from my UC300 from mach 3 USB port, this would then output to an arduino or a pic IC custom board with the relevant coding to then give rotation direction and position to the motor using the encoder as a feedback to correct for any errors.

I understand that a stepper is probably the easiest route but as you know a large stepper motor or servo for that matter is very pricey. Also less challenging

Can anyone firstly see a flaw in my very embryonic idea firstly and secondly if this has this been done which I'm sure it has does anyone have a link for the c++ code of arduino to save me a lot of headaches and surely weeks of time haha.

I look forward to your replies. Thank you in advance.

Kind regards
Dave