Search found 59 matches

by roberlin
Wed Aug 01, 2012 1:28 pm
Forum: Design Ideas
Topic: Belt on outside
Replies: 56
Views: 130112

Re: Belt on outside

If you don't mind ebay, this guy seems to have 12"x12"x1/8" sheets of 6061 for about $4 cheaper than om ... 27c181d5c3
by roberlin
Wed Jul 25, 2012 9:14 pm
Forum: Design Ideas
Topic: New X-axis plates
Replies: 112
Views: 136360

Re: New X-axis plates

I thought I would point out that it seems like the pieces of 2040 from Misumi should be strictly longer than the Makerslide for the x-axis. From looking at the plate diagram and my Shapeoko I'm thinking 2cm longer if you want everything flush (feel free to jump in and contradict or affirm this, Edwa...
by roberlin
Fri Jul 20, 2012 10:59 pm
Forum: Assembly
Topic: Missing steps while cutting
Replies: 11
Views: 4701

Re: Missing steps while cutting

I'm struggling with dropped steps too. Cutting eighth inch plywood with a 2-flute sixteenth inch endmill 0.1mm per pass 300mm/min horizontal feedrate (z limited to 150mm/min via a controller setting). The controller is TinyG on a 24v supply. I added a fan blowing over the heatsinks and have been mes...
by roberlin
Tue May 01, 2012 8:52 pm
Forum: Software - CAD, CAM, Workflow Help
Topic: GCode Sender (Linux)
Replies: 13
Views: 5090

Re: GCode Sender (Linux)

I think the job of the gcode sender is to send the gcode at a rate that your controller can handle (don't want to overflow the buffer don't want it to go empty), and the method of flow control depends on your controller. For grbl it looks like you send a block, then wait for it to say OK then send a...
by roberlin
Tue May 01, 2012 12:23 pm
Forum: Electronics
Topic: Measuring RPM?
Replies: 6
Views: 2024

Re: Measuring RPM?

if it is a brushless motor (seems unlikely I guess?) you can measure the rpm electrically by monitoring the pulses (say with an arduino) coming off the motor controller.
by roberlin
Thu Apr 26, 2012 2:13 am
Forum: Electronics
Topic: Has anyone built a Shapeoko with a tinyG?
Replies: 14
Views: 2512

Re: Has anyone built a Shapeoko with a tinyG?

I'm in the same boat -- after much indecision I finally committed and ordered the tinyg a couple of days ago.

Doesn't seem like it should be radically different to set up than the gerbil. May require slightly different feeding?
by roberlin
Fri Apr 20, 2012 2:25 pm
Forum: GRBL
Topic: Grbl on Arduino Mega
Replies: 7
Views: 5304

Re: Grbl on Arduino Mega

So, I assume these second arduino addons would work simply feeding the GRBL arduino its gcode via serial pins directly? (bypassing the usb) I like this idea. It seems like you could do the same thing with tinyg in place of grbl. Does anybody know for sure whether the stock tinyg firmware supports so...
by roberlin
Wed Apr 18, 2012 8:12 pm
Forum: Electronics
Topic: Stepper motors
Replies: 32
Views: 10094

Re: Stepper motors

I noticed that NEMA 23's seem to be mostly 6.35mm drive shaft vs the NEMA 17's 5mm.

And the default pulley in the shapeoko parts list is 5mm bore.

So, to use the NEMA 23, does one drill out the pulley. Or order a different one?
Or is it a nonissue for some reason?
by roberlin
Wed Apr 11, 2012 12:56 pm
Forum: Electronics
Topic: Stepper driver and Stepper shield
Replies: 28
Views: 10000

Re: Stepper driver and Stepper shield

I also like the idea of the pololu compatible ti-driver board. Something else that might be cool is if there was a grblshield 3d printing upgrade board containing the 4th driver and other necessary components. These could be on a separate shield that is sandwiched between the arduino and the grblshi...