Remaining time countdown in GroundControl?

Been working a lot lately and have not had a lot of time to spend on the Maslow, but I am dedicating today to building the permanent frame.
While cutting the frame pattern, I noticed the “Percent Complete” and wondered what it would take to add a “Remaining Time” countdown. I would really like to know how long these cuts are going to take and that would be the best place to display it.
How do you guys calculate the cut times?

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Welcome to our group. I’m guessing at the way this works. A tool path file is made up of lines telling the system what to do. So geting a percentage as an exmaple let’s say there are 12000 lines of instructions and you are on line 5467. It is easy to calculate.

Because 1 instruction could be move 1 unit up and antoher could be move from left to right the complete length of the sheet of materil it would be very difficult to calculare time based on the the file.

These are my thoughts. Maybe there is a more informed answer.

Thank you

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That makes sense. I was thinking to calculate at one minute at what ever the percentage value was. So, when one minute goes by, and Groundforce is at, say, 25%, then the total time would be 4 minutes. But, based on your answer I don’t see this being accurate at all. There’s got to be a way!

@brandon is correct, it’s pretty easy to say what percentage you are through
the file, but you would have to simulate all the actions to tell how long each
of them take

I previously worked for a CNC manufacturer and we had software notifications for unmanned operation. I would love to see ground control send email or SMS events.

Job Complete
Change Tool


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I think the real answer is to get grbl compatibility so that you can use
octoprint and similar things rather than trying to get every feature added to GC

use what everyone else has done rather than re-implementing it

I do believe that at the very minimum for unattended operation and notification when the job is complete is perfectly suited to ground control. I agree other features may not be.


There’s a point for discussion…

Maslow is robust for a set and forget if you have a Z-Axis so I cannot see why a completion notification at the very least for unattended cutting (You may be inside waiting for the job to complete) could not be accommodated.

If the update portion of Ground Control is implemented with the strategy pattern then and extension notification should be easy (I have not yet looked at the ground control software yet)

Kind Regards Stuart

I’ve had a few situations where the machine malfunctioned. Sometimes I was able to get it all under control before any damage was done. Other times not as lucky. This is hobby gear with restrictions, I’ll stay around and keep an eye on it :smile:.


Given that the system is a work in progress I take your point and it is very valid and prudent.

I do feel however if the unit is to get more widespread adoption sooner or later people will want limited supervision without something going wrong or concern over something going wrong.

Given the improvements seem exponential with community support I have every faith this will become a reality over time.

It is absolutely valid to say this is a hobby device but on the flip side if we were all to be scared to leave the device this will have a negative impact on new users wanting to get a maslow (Again I am not suggesting this is what you are saying).

Having some form of preemptive notification even fault events will only promote uptake.

Kind Regards Stuart

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it’s been discussed - don’t do it …


Not sure I follow Bee? Never leave the device ?


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with any CNC equipment, you really should be close enough to hear if something
goes wrong.

you don’t have to be sitting there and staring at it with your hand hovering
over the kill switch, but you don’t want to go take a shower or go to the store.

This isn’t just that the maslow is a hobby matchine, even the very expensive
professional systems want to have someone relatively close.

If something goes wrong and the system freezes in place with the router running,
there is a very real possibility that it can start a fire (a router bit spinning
in place against wood with no movement, think about starting a fire by spinning
a stick, and how much more friction is involved here)


Or a chain breaks (or other router releasing event) and the router takes off, the motor fails (they’re not designed for long cut times or lifetimes) and let’s out the magic flames on your piece of wood, or any other of a list of potential disasters.

Plus your insurance company may just say sorry, you’re negligent, no pay.

Just like a 3D printer, laser cutter, or a toddler (potentially more destructive…) don’t leave it unattended


I suggest never leaving any CNC device unattended. At best they rely on switches and CPU’s both of which fail. It is unadvisable to not attend to the machine when in use. There are a great number of things that can happen. Minor issues can involve loosing use of the machine. Worst case issue you can loose a structure or lives. This is general to all CNC and machinery. Each person has to decide what unattended means to them. For me I might start a job and set up a desk in front of it so I can see what is happening. There is another thread on this. I’m operating my Maslow in front of my garage if I leave it unattended a stranger could walk up.

I’ll put it this way. The last time I hot mopped a roof, I had a Tar Pot set up in the street. It was marked with a “safe until X”. I made my wife stand 10 ft away in the street to monitor it. She asked was it really necessary. We have lots of kids that go through the area on skateboards.

I explained she had to keep others away and keep an eye on the temperature. Either the gage was faulty or the information was wrong. Either way ~100 under the safe limit the lid blew open under an explosion. That is all that happened the lid blew open. If she were close enough she would have been injured. Being overly safe with tools results in 1 thing - nothing bad happens. Not being cautious enough can lead to catastrophic events. Ask the Moose here he’s a paramedic.

This is free advice

Thank you

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Thanks David,
I don’t share this view having worked for a CNC machine tool manufacturer for 15 years. Unmanned operation was the rule and not the exception however these machines were in the range of 500K to 1.5 Million with more checks and measures and safety systems than Maslow so I can appreciate your viewpoint.

Just felt it would be a useful feature.

Kind Regards Stuart


Thanks for your comments Bee, I can appreciate your viewpoint.



did you leave the machines running overnight and through lunch when there was
nobody in the building? or was there still someone within earshot to hear is a
machine generated an alarm or quit?

I’m not saying you have to be hovering, just that you need to be in earshot.

These were industrial grade CNC machines that would run overnight without supervision. That is not to say that under all scenario’s there were no staff on site as some companies run night shift while others did not. The CNC machines were suited to both manned and unmanned production floors.

You also had customers with loaders that would process batches of parts then send a message that the operation was complete. They also notified of fault conditions hence why I raised the idea.

Again we are referring to apple and oranges in terms of robust systems hence why I appreciate your viewpoint. Maslow does not compare to these machines in terms of their safety systems and cost so some level of supervision is wise as you note for the maslow.

I guess the logical question to ask is how often does the Maslow fail or has an issue as I have not yet completed by build so any guidance would be helpful . The threads would indicate there are issues but it is a work in progress so this is to be expected just not sure how often serious issues arise as looks like there is great stuff coming out of the Maslow Project and not a huge lot of complaints and understand that people will be sitting by their machines.

What I was leading to is remote operation where I could be inside, have a camera on the machine and if required and an error event occurred halt the machine and notify me that intervention was required.

Again they are just ideas and from this thread I can see it is something that would currently be a distraction from the great improvements that are being made as resources are finite to enhance the code.

Kind Regards Stuart