Well, there you go Todd! I already suspected it had to be sought in the electronics/software combo. Glad you solved it.

 

Just did this test piece as a final precision test (didn't had much time lately to work with the Buffalo and tweak it to near perfection);


Result: Perfect circles, perfect square, perfect diagonals. Everything dead-on!!! I think I've now reached the point that the machine is fine-tuned to its maximum potential (and possibly mine too!) of precision and I feel confident enough to start making some serious chips.

Now it's to see how long it stays like this…..

Darn…now I have to start working on some nice designs to carve, cut and model. Off to pump up the skills in Aspire! Tjakka!

Again, Mark and team and everybody else here, thanks a lot for service, help, support (mental one included) and the tons of information here that helped this total nitwit in the field of CNC to reach this point.

 

I have been thinking about adding idler wheels to my X-axis to increase the belt wrap and couldn't figure out a good place to put them.

It never occurred to me to use longer bolts on the motor mounts!

 

Excellent solution @dddman

Tweakie.

 

I did it minutes after taking the picture, I was just too excited to show it to you all

 

Has anyone got a fix for 'spindle creep' ? Here I have a 1.5KW spindle, as a soon as the motors are off, the spindle races downward. I tried to tighten the eccentrics, but that doesn't help much...

 

I'm adding a 24V electromagnetic brake to mine... Just have to find how to make it work with mach3

 

What size stepper do you have on your Z?

 

@KerryH -- NEMA17

I think I'll go towards adding a pair of relays to short the coils when the Enable pin goes down. it brakes the motor quite convincingly -- not /totally/ tho, there's still a bit of creep down, but, at least the spindle doesn't plunge down toward the table!
I think that if I had a NEMA23 on the Z, it'd be enought to brake it entirely... Might see to upgrade it ..

 

I have a nema23 on my Z and w/ the dewalt dwp611 I haven't noticed any issues in that area.

Idk if that helps you any.

 

I have a Nema23 too with a 1.5kW 65mm spindle and in still creeps down when not powered.

 

Newbie question: In the process of planning out an OX build.
Do the 2 Y-axis Nema's connect to the same driver?
If not how are they synced? If separate drivers do I need a 4-axis controller for this?
I've been browsing the builds and forums and really have not come across a detail build guide on the electronics.

Thanks for any help
P. Ry

 

Normally people just use a small gas piston to counterbalance the weight

 

They will be synchronised with the software (very easy with Mach3) and yes you will need a 4 axis driver for that. You can also use the same driver and drive the motor in parallel, but you have half the available power to each motor.

 

Hi everyone, I'm planning to build a CNC mill, somewhat derivative from the OX design. Has anyone used nema17's for the X and Y axes? I'm coming in from the 3D printing world, so I've got a bunch of nema 17 motors lying around. I'm mostly planning on doing lightweight PCB engraving. I've started building a very light weight spindle something along the lines of this: http://www.buildlog.net/blog/2011/09/new-brushless-dc-router-spindle/ so I'm hoping the system won't get bogged down by weight using smaller motors.

 

What I have done is run step and direction wires to each driver from the same output of the bob "break out board"

 

I wonder if there is a way to use an eccentric spacer on that pulley for fine tuning.

 

I was thinking if making a new hole.

 

@Scooter You don't have the space for a bigger hole in the motor. But you can easily make another hole and don't use the screw from the motor

 

Yes that's what I was thinking. Just drill another hole in the plate. That way you shouldn't have to mess with the motor position anymore. if we could make it work for x axis even better. Thanks for the idea.

 

I think I may just add these holes as an option on my plates
Great idea guys

 

I have a new set of plates from Chris, and I was wondering just how tight these should be on the rails. I have them mounted with the white wheels that are supposed to be harder than the black.

I have the offset nuts set to their widest position, but the carriage and x-axis are not easy to roll on the rails they are so tight.

They don't look that tight in the build videos. He's able to move them with one hand. I have to use two hands to move the carriage along the y and x axis.

Suggestions?

 

Check if the distance of the holes in the plates are conform the drawings, if not, ask Chris to correct it. If drawing and plates are the same, check if you assembled everything perfectly right.

 

On the X axis make sure you have the correct spacers in the center and the two beams are tight together. My X axis setup was tight until I resolved this issue.

I found drilling and bolting the two extrusions together really made a big difference because the distance was then consistent.

 

An interesting observation-
I was trying to get my limit switches running yesterday, (I've got the cnc xpro card) and had the fans disconnected. I noticed every minute or so, the Z motor gave a little tick. It took a while to work out what was going on but it finally clicked the the driver chips were overheating and shutting down for a minute then switching back on. It normally would not be a problem with the fans running but it does make me think that I need to fit some heatsinks to the chips.

 

This is my first post here and I was wondering if you guys could help answer a few questions for me. I plan on building the standard OX machine as everything is readily available and I do not have the capabilities right now of accurately machining aluminum. I was wondering if there were any changes you've made to drastically improve the machine without altering the design greatly? I will be purchasing the Clockwerk plates unless someone states a reason I should buy the more expensive sets from fleabay.

Another question I had is that I saw that Kram changed the height of the bed in the later video updates. Does the current bill of materials reflect that?

Another quick question. while I wait for my order to ship, I'm going to be designing and building a custom enclosure for the unit. I was wondering if anyone knows off the top of their head, or can readily check, what the max height of the entire unit is when using the default build guide.

Last thing. To anyone that's built one already and have been using it, is there anything you would do/would have done differently? I plan to use this thing for a while, and use it to build a 4 axis, more rigid machine.