Carbide motion automatic homing not a good idea


(Miguel Castillo) #1

I just destroyed my dust shoe as carbide motion moved the cutter to home position after stopping a job. IMHO I do not think it is a good idea to start the homing cycle automatically. This should be an user’s option.


(Richard Cournoyer) #2

Wait, so this is the first day you tried Carbide Motion? Because we ALL know that there are a few automatic moves (when the program ends, when a program is paused, and when it is stopped). So as an engineer, and as a long time user, your dust shoe was poorly designed.

Now, this may make you mad, but it is my opinion, just like “homing is not a good idea,” is your opinion. You have several options on how to operate your machine and Carbide Motion is just one of them.


(Miguel Castillo) #3

I respect your credentials and experience. I just wanted to point out that the control should be on the user not on the machine. When stopped it, the cutter should go to a safe position and should not start a homing cycle that is not required at that moment. I did not want to offend you in any way and honestly minimizing my opinion is not going to improve the software, I just wanted to mention what happened so other inexperienced users be aware of this risk. I never used the homing cycle before. In fact it was set to false in my settings but I decided to give it a try and it took me by surprise. I do not like to post too much in any forum and based on your response I will try to minimize my participation in the future.


(Jerry Gray) #4

Don’t worry about it.
Some people will agree and some won’t.
Who knows, someone might be in the same boat as you, and come across this thread just in time, and remember to keep the power switch in their hand for an e stop.

Sounds like a hint.


(Chris Bottino) #5

I agree - and I do take this as something to remember, when I get my dust show in the mail anyday!! Thanks again and I am an engineer too (just not like the android type)!


(Carl Hilinski) #6

I wouldn’t mind if the spindle just returned to x0 y0 at the end (with some “tall” z).


(William Adams) #7

The problem here is, one can automate, or one can require the user to manage everything, or one can strive to find some appropriate balancing point in-between. Obviously we’re still trying to find the balance point for Carbide Motion — anyone who has feedback on this, please send it in to Carbide 3D or start a discussion thread as has been done here.

@mecas bummed to hear about your damaged dust shoe — please let us know at support@carbide3d.com and we’ll see what we can do on that.

For everyone else, please remember that on the internet, no one can hear your emotional overtone, so we should always strive to err towards politeness and an effort to understand. I guess emoji are supposed to address this, but I can never bring myself to use them (and ages ago, I used to go to the effort to select emoticons to add to messages).


(Miguel Castillo) #8

Thanks William. Jenn from Suckitdustboot learnt about my problem in this forum and offered to replace the damaged parts for free. What a wonderful customer care.


(Evan Day) #9

Thanks for the additional info Miguel. I have a Suckit on order, and this is good info to know. I assumed from your original comment that it was a homemade dust boot. So now I need to be concerned as well. Do you think anyone with a Suckit model should be worried?


(William Adams) #10

FWIW, there are a lot of dust shoe designs at: https://www.shapeoko.com/wiki/index.php/Spindle_Options

I’ve never liked the idea of fixed dust shoes due to the potential of their getting hung up on clamps and so forth. Went through my design process for my original mount / dust shoe design for the Makita RT0701 at: http://www.shapeoko.com/forum/viewtopic.php?f=8&t=3658 (still using the dust shoe — worked up a mounting system to allow me to use it on an SO3 w/ a variety of mounts)


(Miguel Castillo) #11

Personally I have used both: a home made model attached to the router and the suckit. I have to say that the suckitdustboot is an excellent design and have a higher efficiency in collecting dust. What happened shouldn’t be any different if I had used the home-made model since the clamps I used were fasten with a screw that was too tall. My comment on the homing cycle was more related to the machine moving to home when it was not needed. For my this is not a safe behavior since anything could be on the way of the machine beyond the working area.


(mikep) #12

The new suckit it a lot better than the original SO3 design. That said, you do still need to be aware of where it is, and how big it is, and what your control software is going to do. I do wish that the vertical brackets were magnetically attached to a plate that allowed adjustment vertically, instead of directly to the vertical adjusters…then it would be a lot easier to “break away” on a crash without damage.

I personally would prefer it if on a “pause” or “Stop” the machine would retract, but stay x/y where it is, and not home until I said it was ok. They’re probably not going to make us all happy. If what you wanted was an “emergency stop” that’s officially the power switch. I don’t like that either, but it is what it is. If you don’t like it, the SO is basically just a really complete kit, you’re expected to know sort of what you’re doing, so go add one (the pins are there, and they’re cheap).


(Evan Day) #13

Thanks for the info mikep. I opted for a hardwired e-stop button that kills power to both router and machine at the same time, giving me a true emergency “all stop” capability. That’s mainly there to save me in case I do something really dumb like put my hand into the router bit. But I agree with you, a “short hold” where the machine would go to rectract height but maintain current x-y on “pause” would be great, as well as using the existing rapid position functionality to choose where you want the machine to home to upon job completion.


(Daniel Loughmiller) #14

The only thing I don’t like is that when the job is finished the automatic move lifts the bit and moves to some +Y point. When you cancel a job it lifts and goes home. I do think it should go to the same place, I had a close call with a clamp bolt almost getting hit when I had to cancel a job. Yes the retraction could have been higher but I was peck drilling at a slow vertical feed and it does the slow speed from the retraction height instead of moving more quickly to material 0 then using the slow speed to cut.


(Adam X) #15

I’ll pile on here: The auto-homing post-job in carbide motion seems odd to me as well. My job finishes, then the cutter flees for the hills with the bit still spinning. Yikes. I’m used to it now, but maybe a GUI prompt on the CM side along the lines of “Job complete, please shut off your spindle and press OK to return to home”. Same net effect of keeping things automated, but prevents the machine doing something that (to many, myself included) seems un-commanded.

Emoji, just for Will: :slight_smile::beers::sunglasses:


(Malcolm Overend) #16

I have to agree with the OP. I wasn’t expecting it to auto home and it ran into one of my clamps. I’d love a checkbox option of where to send it after finishing the job. One of the quick positions would be just as good.


(Phil Gorsuch) #17

Have to say I don’t really feel qualified to comment here, particularly as this appears to be more of a SO discussion, but will throw it in here anyways.

Seems to me there can be an opposing pull between proper retraction height and speed of milling when it comes to plunge rates. If one sets retraction height ‘properly’ there should be no problem with crashing on a job stop or job finish. That is, retraction height is set to clear all vertical protrusions such as clamps. The downside is you immediately pay the price in terms of a massive increase in machining time, particularly with low plunge rates. I have to fall in line with general consensus (I think) and say a homing cycle coming off a stop or a job finish should start with maximum Z height retraction whilst keeping the X and Y stable. This might add a little time to that one operation, but allows a better margin for safety in terms of clearing clamps/odd part protrusions.


(kirby) #18

I have noticed this too with mine that I need to look out for where I place clamps to hold down the material. Due to this I think in the future I will be using screws or hot glue to attach work piece to bed for smaller items.

A longer brush may help but then you run the risk off the router hitting the clear plate with the cutout. Or power cord hitting the arms holding the dust boot.

Some jobs may just require working without it on also.


(mikep) #19

This is why some cam systems allow you to specify a “safe” height instead of a just a retract height. If the mill is going outside the envelope of the part, it must use the safe height (specifically to avoid clammps, tooling, etc), but only needs to use the “retract” height inside the envelope. Some systems are even smarter and don’t go to the retract height if they can move directly without hitting material that isn’t cut yet. We’re off into pretty complex features now.


(Dan) #20

I will be upgrading from my 3D printer dust shoe soon to a suckit. Would be keen to see pictures on what exactly happened and how to avoid this. Sounds like it was a unique situation though.

Carbide motion is great in its simplicity and it got me started on my CNC journey. Only new at this. But learning is a process and sharing opinions helps us newbies learn.

Since putting on my homemade dust shoe I have realized and learned that positioning clamps and looking for possible obstacles i.e. Z height are a vital part of the process before hitting begin.