I am considering getting this ATC for my AltMill. It says on the site ot works with MOST spindles. Will the AltMill’s spindle work with this ATC?
Thanks
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I am also interested to know if anyone has successfully setup a RapidChange ATC with an Altmill. The questions we would need to know answers to in order to know it’s compatibility are:
Can I create custom macros on the Altmill/SLB/GSender? Particularly M6?
Can I run the Altmill spindle counter-clockwise with g-code?
Can the Altmill spindle be programmed to run at a minimum of 1000rpm?
So, I have bought one, but have not had time to install it yet. Didn’t realize how difficult it was to get 19mm ER-16 collet nuts.
I have verified that the spindle can be run CCW. You can get the spindle to run at 1000 rpm, but you do have to modify gSender to set the minimum RPM and change settings in the VFD to change the minimum RPM. From what I understand at this point, the ER-16 uses around 2000 RPM. The only issue here is that this will allow gcode to run low. I ran into this problem on an old CAM that didn’t have a controllable spindle and the the RPM was set at 2000 rpm.
I hope to have it up and running in a few weeks. My collet nuts should be here by the end of the week.
Sounds like you have made good progress. I look forward to your updates once you have it working.
I may place my orders since it definitely sounds feasible. Though, the swing turret may be worth waiting for release…
Tagging along because I’ve got ATC at the day job and I’m spoiled.
A reference thread that might help discussion along:
Here’s my SLB+gSender+RapidChangeATC+AutoDustBoot setup.
FYI, I’m using custom gSender version that I modified to make the M6 works with grblHal and skips the dialog confirmation window for M6.
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Thank you. We got distracted, as we are redoing our wasteboard design based on poor performance thus far, so have shelved this until that is complete. This will help quite a bit.
I’m not familiar with how to make this device work with the AltMill or LongMill MK2 but if you could find a way for it to run the $31=1200; command just before doing the tool change then that would temporarily set the spindle’s min speed to 1200, then your could execute the tool change, and then lastly run the $31=7500; command to set the min speed back to 7500. That would allow you to carry on with your carve knowing that if you messed up the speed in your design software, you won’t inadvertently run your spindle at a low speed for your carve.
I got this idea after seeing Sienci’s updated Spindle configuration file that sets all the Firmware by loading the file and running it like GCode.
; SLB (Non-EXT) Firmware Configuration for Sienci Labs 1.5kW Spindle. Created 20241202 by Johann Chung.
$395=6; H-100 VFD Spindle. Default 0.
$374=3; Modbus baud rate. Default 3 (19200bps).
$375=50; Modbus RX timeout. Default 50.
$476=2; Modbus Address. Default 0.
$392=11; Spindle on delay. Default 4 (or higher on later versions).
$340=5; Spindle at speed tolerance. Default 5.
$30=24000; Max spindle speed.
$31=7500; Min spindle speed.
$37=4; Z-axis motor holding current.
Rob
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3 of my 4 Altmill boxes arrived for Christmas. As I await the rest with bated breath, I notice in Johan Chung’s setting the $31=7500; Min spindle speed. I thought the Rapid Change ATC required 1200 spindle speed. (assuming we’re referencing RPM’s) Can you point me to the right answers? I’m willing to read extensively… Thanks.
My suggestion for the RapidChange ATC is to use the grblHAL implementation. It’s much easier than creating macros in gSender. It provides a more natural implementation of the ATC, as you can simply send a command like M6 T1 to change to tool #1 either in your g-code program or through the console and the firmware will do everything for you.
I plan to create a tutorial video once I set up my Alt Mill. Hopefully, it will arrive next week. I’ve been using this with SLB + gSender on my Onefinity, although I had to use different firmware for the SLB and also compiled my own version of gSender. I’ll share both once everything is fully configured.
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If you have your spindle, you can look in the manual, as Sienci sets the low limit foe the speed on the controller as well as gsender. It is near the front of the list, I don’t have the manual in front of me.
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Yes those are RPM values. The Rapid Change ATC folks designed it to load and unload at 1200 RPM for various valid reasons. Spindles tend to not be designed to run at such low speeds. However, that doesn’t mean that they can’t run at low speeds for a short time. I’ve seen a few posts where people have said that they ran their spindle at the lower speeds (like 1200 RPM) to do the tool change and then brought the speed back up to normal for their carves, all with no problem.
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All as I am beginning to understand. I’m sure you’ll be thrilled to hear that my Altmill just arrived. Well, I am. I’ll spend a few weeks getting used to it before I invest in tool change.
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Here you go. First Alt Mill with RapidChange ATC fully working.
M U S T … H A V E !!!
Alas, I wouldn’t know how to set this up if it isn’t turnkey 
I will create a setup video if I got some time.
The only setting you need to adjust in the firmware is to allow a minimum speed ($31) down to 1200 RPM. I set mine to 500 RPM. You don’t need to keep changing this, as the spindle speed is dynamically controlled by your G-code during the job. The macros will also handle the spindle speed adjustment automatically.
Here’s how it works: In your CAM software, ensure it inserts the M6 Tx command for the toolchange, where x is the tool number. The firmware will automatically interpret the M6 G-code command and execute the tool change macros accordingly.
That sounds deceptively simple. Where do the macros come from? How does the Altmill know where the tool positions are? There has got to be more to this …
A setup video would be excellent!
It’s on their website:
https://rapidchangeatc.com/docs/integration/grblhal/
You create a copy of these macros and put it on the SD card. Modify the macros based on your setup, such as the X or Y orientation of your magazine, the location of your tool setter, etc. Then, insert the SD card into the SLB+EXT (Alt Mill Controller). Follow the remaining steps to execute the macro initialization automatically when the board starts.
It’s actually not that difficult. The owner of RapidChangeATC hasn’t created any video specifically for SLB yet. I think I’m the only one doing this so far. 
I’ve just been too busy working on my AutoDustBoot.