@Robert Hummel

I am using the setup in the OX build ... Arduino with gShield v5. Current is set by 3 pots by turing up until keeps running without heat issues.

• 2.5 Amps per winding
• 12-30 Input Voltage
• Open Pin Pass Through
• 8x Microstepping
• Screw Down Terminal Voltage Input
• Hardware 3x Axis (x,y,z)
• 3x Robust TI DRV8818 Stepper Drivers

The motors I am using are not the best Nema 17's ... they are
Kysan Electronics NEMA 17 Stepper Motors for 3D Printers 42BYGH4803-DC

• High Torque: 5.5 kg-cm, 53.9 N-cm, 76 oz-in, 4.77 lb-in
• 4.2 Volt, 1.5 Amp, 1.8 deg per step
• 21 mm long, 5 mm Shaft with D Cut
• 2 Phase, Resistance per Phase 2.8 Ohms
• 200 Steps per Revolution, Inductance 4.8 mH, Class B Insulation

I plan to change to Nema 23's per OX build with OX plates and use a 1 hp router.

You have 360 watt supply, more than twice what I have now ... I have 480 watt (24v, 20 amp) on order from the store here, should have it on Thursday.

I can cut Garlite OK with my setup now, will try it again soon to cut OX plates ...

@Robert Hummel

I cut the Garlite dry ... and have seen some people cut aluminum dry, blowing or vacuuming out the chips. I think I will try some 3-in-1 oil, or some other light cutting oil next. Crisco seems like it would eventually go rancid?

@Robert Hummel

Thanks for the tip about Crisco oil.

I realize the Garlite dust is carcinogenic, so OK, will try a bit of soapy water .... but dust is not too bad, does not get more than a foot or two from the bit, and I vacuum lots.

For aluminum I have been trying these bits from LakeShore Carbide, seem like well made bits:
1/8" Rougher/Finisher Variable Flute End Mill for Aluminum ZrN
1/8" Rougher/Finisher Variable 2 Flute End Mill for Aluminum ZrN
maybe these are the wrong bits? But I have tried a few others also.

Really seems like a power issue that is also affecting the Arduino, as it looses the USB connection at times. When I air mill, no problems.

@Robert Hummel
Yes, helps to know I have the right bits.
Yes, good idea to use the powered hub, I certainly have done that with Raspberry Pi, and even have one on the shelf, so will use it. Actually I was thinking of powering Arduino from separate 5v supply and using Bluetooth Arduino, but not sure if I can get that working yet ... I left my Blue Tooth Arduino in Beijing apartment, where I play around with simple robotic stuff. Maybe I will try to source some good stepper motors, etc. next time I am there.

Made a bit of progress today with powered USB hub, and unplugged and re-plugged everything ... but still seems X and Y motors are underpowered. I will play with current limits a bit, and see if I can keep the motors running and moving the bit correctly. Checked 24v, seems to be holding up OK. So seems to be a matter of finding the right settings ...

Got most of my parts in for my build starting on it soon. About to find out the quality of the parts list I got. (hopefully good)

When I switched back to cutting Garolite for OX plates, which I have modified for 60 mm rails to run on the Routy base, I had to tweak setting for motor current on the gShield. Seems I had them set for too much current, they would run the motors a few minutes, then overheat. And it seems slow speeds make for more tendency to overheat. So now cutting Garolite with same bit I had for aluminum at 450 mm and 0.667 depth per pass, with no problems (have completed about 20% of cutting for the 4 plates in about an hour). Seems to be cutting true ... logos look good in black Garolite. But I will switch the build to OX X and Z build and add Nema 23 motors before I try aluminum again, with a 1 HP spindle also.

About to give the electronics their first run. Hoping my ineptitude doesn't rear it's ugly head.

@Bryant
Good luck. Just so long as you get the power hooked up correctly, rest seems pretty forgiving based on my experience

Good to hear. I'm using the 12V 30A power supply I bought from the parts store. Should I be adjusting that down in Amperage at all? As near as I can tell that is the only adjustment available.

IF you are using the gShield .... you need to follow the procedure to set the small pots on each x, y, and z driver .... turn them gently all the way CCW then slowly CW until motors begin to run steadily, then a bit more CW. Warm motors are OK, hot ones are not, they will stop working. Did you read the WIKI on the shield and on the TinyG ... I think the motor adjustment procedure is actually in the TinyG WIKI.

I'm using the Protoneer shield. I've got GRBL installed and the Universal G-Code Sender is communicating with the board. However, I am not getting any movement when I send commands. The protoneer shield doesn't appear to have a whole lot of documentation so I'm working through it.

Wasn't the shields fault at all. Evidently I should look at the correct driver board when orienting them on the shield The Pololu DRV8825 has the pot on the opposite side. Once I lined up the enable pin on the driver board and shield I have movement. Now to tune them in.

Lucky you didn't fry it

@Robert Hummel

OK ... thanks. I will try a bit of wax ... when I try again.

@Bryant

Docs on the Protoneer shield seem pretty good actually ... I assume you have looked here?
http://blog.protoneer.co.nz/arduino-cnc-shield-v3-00-assembly-guide/#FirstRun

Forrest,

You are quite correct. Once I figured out that it was my positioning of the Pololu drivers that was the problem the shield's documentation was just fine. And to be honest, if I would have stopped and read the part about lining up the enabling pin on the shield and the board I would have saved an hour of head scratching

Chris, I do feel lucky that I didn't either kill the shield or the drivers. I did just find out that pololu is here in Las Vegas so I guess I have quick access if I do blow one of these boards.

On another note, can anyone explain how to test the current your stepper is pulling. I'm a bit of a electronics newbie (computers fine, electronics - not so much).

Bryant

I'm no expert, but the pololu website suggests putting a multimeter on one of the pins going to your motor (i.e. measure the current across one coil) with the stepping set to single step (no microsteps) and the motor stationary. This will then be 0.7x the max current the driver will draw. The max current value should be just less than the max current specified for the motor.

I finally got my machine built guys. Its a bit of a black sheep though because the parts list was (as expected) wrong and had to just make it work. 20x80 on the side for the gantry supports and 20x60 for the Z and Y axis. A bit of a hack but it should work just fine.

I got to the electronics portion thinking this would be the easy step. lol. Has anyone flashed an arduino with the grbl shield hex file using an arduino? Is such a thing even possible or must I buy an Amtel programmer for this. Basically I need to get this .hex file on the chip but everything I have tried in avrdude has not worked. The arduino i'm using is a ATmega328P on an uno board. Connected via USB on com5. Each attempt has ended in "avrdude: stk500_getsync(): not in sync: resp=0x00 avrdude done. Thank you."

I love how it thanks me for the fail

Thank you. I will give a shot as soon as I'm back from a business trip. Glad someone has done this before

Just got back from the trip and thought I would post my results. I tried to upload my hex file but I'm not sure it is working or if it even worked. I'm guessing no because XLoader still has "Uploading..." down in the status bar for about 5 mins now. 5 mins for 74 k tells me that something is wrong. I followed your instructions and didn't change anything, I only selected the port my arduino is connected to and pointed it to the .hex file.

I just tried to click the application and it doesn't seem like its responding at all.

Dis-regard that.... stupid me choose the wrong chip. In my defense its late and I've been flying all night. Say's upload complete. I'm going to power it up and see if I can get it to respond to grbl controller now.