Hi Martin,

You should be using a separate stepper driver for each motor then the two axes (Y & A ?) are slaved together. Connecting two motors to one driver is really not a recommended practice.

Tweakie.

 

Is it normal to refer to the siteside to side gantry as the X axis?

I always thought front to back was X, side to side was Y, and up/down was Z

 

Mine is finally alive and kicking. I'm still finalizing all the working wiring and the electronics box, but it was moving today.



I'm being super picky about the wiring. I bought the correct color wires to match the stepper, 2x2 molex connector parts, braided cable sheath, cable chain. The whole nine yards.


I also built a BLDC spindle based on the parts from Robert and it rocks. Once I get the PWM signal from the TinyG worked out to control the spindle I'll be happy.


I also have to find a good way to mount the stops.

Overall I'm super excited.

 

Nice work, all the extras and fine details will save a ton of head scratching.
We'll done !

 

I had an "oh s#!t" moment tonight when I hooked up the X axis for the first time and had the polarity for both motors set the same. The machine tried to rip itself in two.

 

Lol bin there hahaha
I did the same with my laser v build, glad the motors stalled before bending anything

 

Oh and for me it's always bin, if standing in front of my mill.
Y Axis = forward backwards
X Axis = left right
And Z lol up down

 

Since I'm still in the middle of wiring up the electrical box and limit switches, I haven't wired up the e-stop yet. I had to listen to the horrible sound of the pinion spinning against the belt.

As for the XYZ thing, I always think of X first and the front to back axis as the first as well.

 

It could be that I'm a Mach3 user also and that's how they have the jog interface setup so I always went with that
Really all that matters is that you end up with the finished results you expected

 

Hi Lee,

It is conventional to have the Y axis 'towards and away' and the X axis 'left and right' as you stand at the machine.
This is the same convention by which most CAD / CAM software produce their GCode but the choice is yours and there is nothing wrong with using conventional or not.
However, there is some advantage with having the X axis as the axis with the lowest total mass. This enables better overall machine performance when producing work (such as images, lithophanes etc.) which requires a 'raster scan' type of movement.

Tweakie.

​

 

Thanks for that. I am very new to this and possibly naively thought that my machine would come with a full set of build instructions and a wiring diagram purpose made to the supplied components, Wrong! Using OpenBuilds YouTube video I have constructed the Machine but my weakest aspect is electrics and I am really struggling, is there anywhere I can go to, to get a wiring diagram or instructions for my configuration:
3 x Nema 23 Motors
1 x Nema 17 Motor
CNC USB Controller MK2/4
4 x TB6600 Drivers
Professional Power Supply
4 x Micro Switches
I have watched the above video from GRAYUK but straight away the terminals he talks about have different names to ones on my controller! Thanks,

 

I have this for the driver

 

Most people use of the router is based upon a "Cartesian Plane". Where the movement away from zero is always positive. So if you lay out the "Cartesian Plane" then use the upper right quadrant as your plotting point you will have the methodology used in most CNC machines. Also the directions of movement are usually based upon standing in front of the machine. Remember that this design is based upon the 50's and 60's and there was no such thing as "new math".

Bob

 

Mark, when would you have everything in store? I would love to build the larger OX, but some things are out of stock? I'm in Thailand, and sourcing things here is to say it friendly, extremely difficult.

 

Thanks Chris, for the offer. But What's missing for me at the moment are the v-slot 20x80 and the nema 17 stepper motor. The plates and the other stuff I can machine here.

 

I try opening up the "OX Plates True Circles_mm.dxf" file in the Files section in DraftSight but the objects are all messed up. Individual holes aren't holes and the outlines seem to merge at random with the holes. Can someone help me export that dxf file to svg? Has anyone have much luck opening the dxf file in Draftsight?

 

Try librecad. I had trouble with DS and iirc, librecad worked.

 

Hello everyone, I am mechanichally inclined and a hobbyist woodworker. I'm new here and planning to build a cnc router (most probably the OX). Thank you Mark for sharing the build and details it is very generous of you.
I do however hope to make a full 4' x 8' one with a 1617 bosch router and hopefully it is possible, my question after going thru most the messages in this topic is.... Can I use a stiffer aluminum for the gantry cross-beam (z-axis) maybe the 25-5010 from 80-20 inc. http://8020.net/T-Slot-5.asp
I plan to use it mainly to cut sheet goods to dimension and shapes..
I know I would be having problem with the groove slightly wider for the wheels to slide onto, but is there another option that you can suggest? I do wish to get most parts here but to save a bit, the extrusions might be sourced locally here as I am in the Philippines.
Mabuhay (long live)......
Sonny

 

Hi Gray,
Tthanks very much for your help, the hyperlink was helpful, I now know a hell of lot more about stepper motors than I ever did, full movement, 1/2 movement and micro movement! Anyway PlanetCNC have sent me a wiring digram which looked perfect all the terminals on my Driver and Controller named 'Common Cathode' but then I scrolled down to find another diagram labelled 'Common Anode' the only difference appears to connecting GND in Cathode and *5v in Anode. I feel I'm getting really close to being able to wire them up but just wanted to check, does it matter which option I go for?

 

I found these wheels a while ago. They'll supposedly work on larger 15 series extrusion from 8020

 

Rick, thank you for the reply. Very much appreciated especially having another extrusion to stiffen the cross beam on the gantry.

Lee the link definitely very helpful, thank you very much. Now I believe I might end redesigning the gantry sides just to be able to make use of these. I do hope everything else need not be changed though....

 

I tried opening the file in librecad. Still has the same issues. Some holes are incomplete. Can someone help me convert Ox Plates True Circles_mm.dxf to a format that can be open by Draftsight or other similar programs?

 

The DXF I used to have my plates waterjet cut is attached in this forum post, http://www.openbuilds.com/threads/waterjet-cut-aluminium-ox-gantry-plates.389/

The circles are not true circles, but many segments. I used Draftsight to read it.

Cheers
Anthony

 

Hi Martin & Gray,

It is perhaps a point best taken up with PlanetCNC - Although I can see possible applications with 'common anode' all of my machines are 'common cathode' and that is the system I would recommend you adopt.

Tweakie.

 

I designed a 3D printable clamp to suit my Makita RT0700C Router but it would work with any Router or Spindle with a 65mm body diameter.

I can alter the design for other diameters if requested.

I've uploaded the STL's to thingiverse, http://www.thingiverse.com/thing:398695/#files

Cheers
Anthony