# Rotary tripping A-axis limit switch **URL:** \ **Category:** General Chat\ **Tags:** rotary-axis\ **Created:** [April 6, 2025, 11:54pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583 "2025-04-06T23:54:57Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![ebeeks](https://avatars.discourse-cdn.com/v4/letter/e/a183cd/32.png) [@ebeeks](https://forum.avidcnc.com/u/ebeeks)\ **Post date:** [April 6, 2025, 11:54pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/1 "2025-04-06T23:54:57Z")
I am trying to carve something on the rotary. Rounding and Rough toolpaths work fine, but when I get to the finish toolpath it says, I have tripped my Limit Switch on the A axis and I notice the GCode has an F0.0 entry in it. Not sure that has anything to do with it, but I tried a couple different things and a line with that entry is what trips it. I am still a novice on the rotary having only completed a few jobs so far. Is this a mechanical issue or did I set my job up to where it will fail? I am attaching a preview of what the finished item is supposed to look like when finished. ![Screenshot 2025-04-06 185344](https://canada1.discourse-cdn.com/flex027/uploads/avidcnc/original/2X/8/8cd339da6d26a7a85e1275908f44d5a83172d95d.jpeg) ---
**Author:** ![Eric](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/eric/32/3220_2.png) [@Eric](https://forum.avidcnc.com/u/Eric)\ **Post date:** [April 7, 2025, 12:33pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/2 "2025-04-07T12:33:32Z")
What control are you running this on? Also, very cool carving ---
**Author:** ![ebeeks](https://avatars.discourse-cdn.com/v4/letter/e/a183cd/32.png) [@ebeeks](https://forum.avidcnc.com/u/ebeeks)\ **Post date:** [April 7, 2025, 12:56pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/3 "2025-04-07T12:56:09Z")
Its Mach 4 and Aspire 10.5 is generating Gcode ---
**Author:** ![Eric](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/eric/32/3220_2.png) [@Eric](https://forum.avidcnc.com/u/Eric)\ **Post date:** [April 7, 2025, 2:41pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/4 "2025-04-07T14:41:58Z")
You might dig around in here to see if you see any answers: > **[Rotary Axis - Troubleshooting](https://www.avidcnc.com/support/troubleshooting/mach4ControlsProCnc/rotaryAxis/)** I don’t know the answer myself, but it sounds like the proximity sensor is triggering a limit error on the machine when it shouldn’t… Maybe check to make sure it’s plugged into the right port? Or go over the rotary assembly to make sure everything is good… ---
**Author:** ![ebeeks](https://avatars.discourse-cdn.com/v4/letter/e/a183cd/32.png) [@ebeeks](https://forum.avidcnc.com/u/ebeeks)\ **Post date:** [April 7, 2025, 3:39pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/5 "2025-04-07T15:39:24Z")
I just went out to the machine and fired up the job again. Here are the screencaps from the screen and the state of the sensor for the a axis when it stops. Sensor isn’t tripped. I keep looking at F0.0 as part of the cause, but I don’t know gcode enough to be sure. ![20250407_152415985_iOS](https://canada1.discourse-cdn.com/flex027/uploads/avidcnc/original/2X/6/662cb3b695a8475dcd52e90e53920ce0ed8f353a.jpeg) ![20250407_152442712_iOS](https://canada1.discourse-cdn.com/flex027/uploads/avidcnc/original/2X/7/7469e6d5330da14b4cc6bc9bb582e9842fc21872.jpeg) When I ran the job last night, I changed from raster to offset to get it to start in another area and when it stopped, the gcode command ended in F0.0 as well. ---
**Author:** ![Eric](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/eric/32/3220_2.png) [@Eric](https://forum.avidcnc.com/u/Eric)\ **Post date:** [April 7, 2025, 3:53pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/6 "2025-04-07T15:53:48Z")
My only guess… and this is a guess is that perhaps you have another sensor plugged into the A port? I’d open a support ticket and you’ll get someone who would know better than me 🙂 ---
**Author:** ![ebeeks](https://avatars.discourse-cdn.com/v4/letter/e/a183cd/32.png) [@ebeeks](https://forum.avidcnc.com/u/ebeeks)\ **Post date:** [April 7, 2025, 3:58pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/7 "2025-04-07T15:58:39Z")
Will do. This is just happening on the fiinish pass. The roughing and rounding paths are fine ---
**Author:** ![berrianmtn](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/berrianmtn/32/4852_2.png) [@berrianmtn](https://forum.avidcnc.com/u/berrianmtn)\ **Post date:** [April 7, 2025, 4:36pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/8 "2025-04-07T16:36:50Z")
I might be missing something here, but how can you have a zero feed rate? Isn’t that saying “rotate to position y at zero speed”? ---
**Author:** ![ebeeks](https://avatars.discourse-cdn.com/v4/letter/e/a183cd/32.png) [@ebeeks](https://forum.avidcnc.com/u/ebeeks)\ **Post date:** [April 7, 2025, 5:08pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/9 "2025-04-07T17:08:11Z")
Why would Aspire generate that in the code? And why would it result in a limit switch trip error? I have run a few other items on the rotary without issue. Could it be because I am going through 0,0 on the rotary? I opened a case, but hope to get a quicker resolution as I have a live job sitting waiting to finish. ---
**Author:** ![grossmsj](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/grossmsj/32/4903_2.png) [@grossmsj](https://forum.avidcnc.com/u/grossmsj)\ **Post date:** [April 7, 2025, 7:12pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/10 "2025-04-07T19:12:40Z")
Did you try editing that line to something like F10 (slow) or F10000? ---
**Author:** ![ebeeks](https://avatars.discourse-cdn.com/v4/letter/e/a183cd/32.png) [@ebeeks](https://forum.avidcnc.com/u/ebeeks)\ **Post date:** [April 7, 2025, 7:24pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/11 "2025-04-07T19:24:05Z")
I haven’t tried editing anything as I didn’t know what I was doing. Is the just speed for feed rate? ---
**Author:** ![grossmsj](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/grossmsj/32/4903_2.png) [@grossmsj](https://forum.avidcnc.com/u/grossmsj)\ **Post date:** [April 7, 2025, 7:49pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/12 "2025-04-07T19:49:43Z")
Yes. F is the feedrate. So in a text editor change it to something other than F0.0. You have to save it in the same format it was in originally, not as a text file (eg, not ending in .txt). That line is telling it to rotate to a position at zero speed. I have no idea why that would happen, but its easy to find out if it works. The other thing that worries me about this is that the command is to Z0.0 in the line before, which for rotary would be the spindle axis or the middle of your work. Are you actually running this file? I don’t want to see the work ruined. ---
**Author:** ![djdelorie](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/djdelorie/32/515_2.png) [@djdelorie](https://forum.avidcnc.com/u/djdelorie)\ **Post date:** [April 7, 2025, 9:37pm UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/13 "2025-04-07T21:37:43Z")
Beware the system might be in “inverse time” mode, where F0 means “complete the operation in 0 minutes”. Commonly used with a rotary axis, else is the F value inches per minute, or degrees per minute? > **[Mach4 G-Code and M-Cod... | MachMotion](https://support.machmotion.com/books/software/page/mach4-g-code-and-m-code-reference#bkmrk-g93-%E2%80%93-inverse-time)** > > Introduction > G-code is a special programming language that is interpreted by Computer Numerical C... ---
**Author:** ![ebeeks](https://avatars.discourse-cdn.com/v4/letter/e/a183cd/32.png) [@ebeeks](https://forum.avidcnc.com/u/ebeeks)\ **Post date:** [April 8, 2025, 12:08am UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/14 "2025-04-08T00:08:47Z")
I ran it and it just quit there. I got some time this evening and tried some fiddling with it. Changed bits, tried running in the air above the piece, tried just one of the pieces on the spindle. None of them worked. Then I decided to insert 1/2” diameter rod model down the center to prevent the bit from extending past Z0 and that worked! I just have to cut that part off and clean it up when it’s done. Not ideal, but it worked and got me moving again. ---
**Author:** ![ebeeks](https://avatars.discourse-cdn.com/v4/letter/e/a183cd/32.png) [@ebeeks](https://forum.avidcnc.com/u/ebeeks)\ **Post date:** [April 8, 2025, 12:09am UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/15 "2025-04-08T00:09:43Z")
I am using the avid post processor and I believe that is in degrees, but not certain. ---
**Author:** ![grossmsj](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.avidcnc.com/grossmsj/32/4903_2.png) [@grossmsj](https://forum.avidcnc.com/u/grossmsj)\ **Post date:** [April 8, 2025, 1:03am UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/16 "2025-04-08T01:03:36Z")
That’s pretty bizarre, in a lot of ways. It sounds like Aspire tried to create a toolpath incorrectly, the post processor spit out some mangled G-Code, and Mach 4 misinterpreted that mess with an errant error code. Sort of a CNC version of Air Disasters. 😉 I’ve never tried to make anything even remotely like that on the rotary. Glad you got your piece out of it. If you figure this out down the road, I’d love to hear what is going on. It would be very instructive. ---
**Author:** ![ebeeks](https://avatars.discourse-cdn.com/v4/letter/e/a183cd/32.png) [@ebeeks](https://forum.avidcnc.com/u/ebeeks)\ **Post date:** [April 8, 2025, 1:50am UTC](https://forum.avidcnc.com/t/rotary-tripping-a-axis-limit-switch/4583/17 "2025-04-08T01:50:24Z")
I did open a case with Avid. However, I don’t think this is an Avid problem now. Something to file away in case you need it. :). Thanks for the feedback. It got me thinking and helped me solve my problem.