OpenBuilds OX CNC Router in Australia

[ledaero]

The other alternative is a German-made AC spindle. No PWM control, but so what.

I would go for a Kress 800 or 1050. Awesome accuracy, AC easy. Adjustable speed.

Kress 06082101 FRÄS UND Schleifmotor 800 FME | eBay

[duke149]

I finally got around to working on my CNC again. Long story short, I had to build a shed for it...
But anyway. I am now using new stepper driver controllers as the old step stick ones kept failing. The project would start cutting properly until eventually they got hot and it would start skipping steps.

The new ones are a lot more powerful but I now have a new issue.
Each layer cut ends up in a different place.

Here is an example

The first one i tried cutting was a heart, the second was a square.




The new drivers I am running are




Does anyone know what I am doing wrong?

[duke149]

Hmm I think I fixed it by changing it to 16 microsteps and recalculating the steps per mm.
Still need to do some more testing.

[gava]

Hi All,

All the bits are in, and the build is coming to a close here is the pictures.

I built this CNC with my wifes business partners husband, we're building it for their work and it was a great little project to

The CNC is using the OX (1500x1000mm) plans with some changes (mild) a Nema23 for Z and got an anti backlash setup also double belting the tracks.

Here we find out how it goes together.


Putting the gantry together


Putting all the ends on, I did a stupid thing and when tapping the ends I snap a cheap bit off in the top hole which i thought he didn't need until we held down the belt. We worked around it but doesn't look as neat as the other ends


putting the Z on


attaching end stops (we've since change the micro switch to one with an arm not just a push button)


Found I had some cable covers I used for my power cables when buiding my brewery and it fits in the v-slot and covers the wires like a boss.


Mounting the Tingy within a project box, I kept it small so it wouldn't get in the road, however this made wiring a touch hard. (I didn't have the correct flame or head shrink so they're pretty much useless might change with something else)




Got a frame built for the CNC the guy that made it was fantastic mm perfect and fit like a glove, leveled then screwed into place.


Wired up and ready for the bottom board to go on. the wires on the side (red and black) have been fixed up this picture is a little old. Old mate is fitting the Y end stops.(the Z axis wire wasn't fixed correctly as you can see in this picture its since been fixed)


Wiring has been done for the motors and X Y end stops this picture is mid wiring.


Here is some test draws I did, Actually learning about CAM / gcode and chilipeppr. Slowly getting there. I changed up some speeds and limits so now its working pretty sweet. Next is to get a spindle and the base boards.



The build has been great! the v-slot and "kit" was good. If i'd make another one I'd defiantly find other screws from the local hardware store to save some cash. the only real need for the low profile screws are on the router bit that slides along the Y. I know i was told this in this thread but i didn't know much about it and though I'd just get the 'kit' and see.

I got my parts from makerstore and the guy was fantastic with help on phone/skype up until I brought the products then he went cold and never replied to any of my skype requests. Granted I never tried to phone him but he was so quick on Skype chat I thought why should I?

Cheers

[gava]

Little update....

Had an issue with not drawing/cutting correctly found a few issues with mine.

Double Belting - With the double belt system we glued the bottom belt on, on the Y axis the bottom belt some slightly to one side up one end this made the top belt move across to one side slightly. When the belt went over the sprocket it moved forward this then caught on the inside front of the sprocket and lost a few steps. I had to move the sprocket forward a little so it wouldn't catch. Issue with this was I'm using an Nema23 motor on the Z and the plate size is bigger than the nema17 I had to move the sprocket on the Y slightly forward and leave enough room for the Z nema23 plate to move down. If it was 1mm to far out the Z plate would catch and move the Y slightly when it went past. Once I dialed this in the Y movement was sweet!! So what did I learn? When/if you glue the bottom belt MAKE SURE all of it is in the middle and not off center AT ALL.

Loose/Missing bits - First test I should have done was put all my motors into 'locked' mode like when changing tools so it shouldn't move. When i did this I notice one X motor was moving, the grub screws hadn't been tighten or had come loose. Also I currently don't have the Z limit switches in and by mistake tried to move 200mm up in the Z my z is only 100~mm movement this obviously went a little bad, after awhile i went around and checked all my bits since it wasn't cutting correctly and found ANOTHER grub screw missing, this time on the bottom screw fastener. This allowed the bottom bearing to pop out of its spot and now the screw wasn't seated correctly. Found another grub screw put it in seated everything (Had to move the spindle 20x40 v-slot forward from the bottom nema23 plate since the grub scew was catching)

Bearings - I had a bearing that had been deformed somehow on the bottom on the Y - this was replaced but didn't really affect anything it was just sticking, once i got it out it look like it may have been over tightened.

From this I put my base and spoil board on and did a couple test cuts.. I moved the spindle into the known area where the belt was having problems and cut a 50mm circle, got the ruler out and it was pretty much bag on, give or take 0.05mm

Oh, also decided on a Matika trimmer (the older version 700w) there is a newer version floating around which is 500w.. the 700w version is doing what i need it to do so far but it's early days so lets see.

cheers