Shopmade Rotary with Laserweb and GRBL LPC.

Shopmade Rotary with Laserweb and GRBL LPC. I’m sorta cheating right now as I didn’t configure an A-Axis. While the Multi-Axis GRBL Firmware worked, it broke the homeing functions on the standard engraving mode. So I switch the Y Axis stepper with the Rotary and then make adjustments to the Steps per MM using a Macro in LaserWeb.

In case someone wanted to see it running…
missing/deleted image from Google+

@Kelly_Burns ​ are you sharing the files?

I thought I had posted a rotary version with working homing for the c3d mini. I have to look into it. I run the 3axis version on my laser currently.

Nice work!!!

@Ariel_Yahni_UniKpty I will certainly make everything available as soon as I can organize and clean them up.

@Jim_Fong That would be great. The one you gave me worked great, but didn’t accept the a-Axis commands. The latest multi axes version, didn’t seem to help me correctly.

@Kelly_Burns try this version. Make sure you save/write down your current grbl settings before flashing the board.

@Jim_Fong thanks Jim. I’ll try this out tomorrow.

Kelly is on a smoothieboard, no? C3D build has no digipot, sb needs digipot.

@raykholo would have to compile a special version for him then.

My last version of the multi-axis branch should work, you just have to connect all endstops to the negative endstop pins (even if they are physically on positive side).
There is also a endstop pin for the A-axis at p1.29 (Z+).

Gentlemen, thank you for the interest and help… here are some answers and information to fill in the blanks…

  1. I am actually running an MKS sBase controller because I fried the x and y drivers on my original Smoothieware board. I am currently using Jim’s GRBl LPC firmware that he compiled for me a month or ago. I did not realize this until I went to enable the rotary and it didn’t work and then could not get back to working order.

  2. I won’t have access to the machine until this evening, but I’m fairly certain I’m using NC setup. I use RipRap end stops because they are inexpensive and provide easy mounting. I modify them so they behave correctly. Provide Ground until the switch is triggered. I have done this with other GRBL setups in the past. In that case I was modifying source and compiling my own and maybe that’s the difference.

  3. With the 3 axis version (compiled BIN from Jim) I do not have any connections on the Z end stop and it seems to work perfectly. Perhaps this is something that is different in Jim’s Version?I don’t have the source, so I couldn’t tell.

  4. Whenever I make progress with configuration, I save the firmware and the current config to a backup folder. It only takes one time to screw something up.

  5. I changed my settings in my Smoothie setup to match the GRBl LPC ones. I am able to switch fairly easily between Smoothie and GRBL by swapping out SD cards. There are no wiring configs.

  6. My year long medical treatment ended about a month ago. Now that I’m off some medication I had been on for a while, my mind seems to be more clear and I am better able to think critically. Hopefully I won’t require as much maintenance and hopefully become a contributor to the group.

  7. I purchased another K40 a few months ago. I bought it with the sole purpose of documenting the conversion and mod end to end. I will likely do this with a 3CD as I like the support Ray provides. Unfortunately, this one doesn’t need the ribbon cable conversion and it already has mechanical end stops.

@Kelly_Burns not familiar with mks board but if my 3 axis version works then the 4th axis version should too since the end stop pin settings are the same. If not, I have to check the source code to see the difference. Let me know…

@Jim_Fong I guess it’s the same or similar microprocessor. But it isn’t nearly as nice. I would rather not be using it, but after I fried my SW, it was going to be 2-3 weeks to get replacement SW board or C3D. I had this one on-hand for a future 3D printer build. I have the Bad Smoothieware board working as a 3 axis controller using external drivers, but I wouldn’t want to rely on it. At some point if you could share your source code, I would appreciate it. I feel like I will be able to tackle that once this med is completely out of my system.

@Kelly_Burns its @cprezzi grbl-lpc branch. It’s an older version where I had to change the end stop pinout myself. His latest version already has the correct changes made. Probably better to use his latest version.

I don’t think using your smoothieboard with external drivers would be a issue unless there is something else damaged on the board. As long as the step and direction lines are isolated away from the damaged on board drivers, you should be ok. Sometimes external drivers are better. Most decent ones have opto isolation to protect the the controller board from damage. Besides my laser, all my other machines use external stepper or servo drivers.

@Jim_Fong thanks, that’s what I was going to look at. I’ll use yours for backup since I already switched my pinout physically, but I will start with Claudio’s source. Thanks again to both of you.

@Kelly_Burns here’s my compile instructions

https://plus.google.com/114592551347873946745/posts/4zw8XvssFMu

@Jim_Fong funny you mention opto-isolation. That’s how it got fried. I didn’t disconnect the steppers when I was aligning the laser and Generated. Some voltage moving the axis manually. Was shocked to learn the controller didn’t have the protection. I actually do not like internal drivers for this reason.

@Kelly_Burns if you manually move the stepper shaft fast enough, it will generate voltage that will back feed into the stepper driver output stage. High enough voltage will damage almost any stepper driver. A optocoupler won’t save the driver in this situation. It will protect other parts of the controller board. The gecko drivers I use are good for 90volts or so. You really need to spin the stepper fast to damage them but you can if you tried hard enough. I think the ones built into the smoothieboard are rated to about 45volts max then they will pop.

What actually helps in this situation is using a good old linear type power supply for the stepper drivers. The big capacitors will help absorb the back fed voltage and prevent driver damage.

Modern switching power supplies don’t have big output capacitors.

@Jim_Fong All is well with the 4 axis version except the “Set Zero” command in LaserWeb is not actually setting zero on the controller and the numbers do not change. In addition to homing, this is the issue I had with @cprezzi compiled version. And thoughts gents? I’m assuming its a setting I’m missing. Homing works perfectly.