New Shopbotter here, with a stalling problem?

[mercuru049]

Greetings!
New to the forums. I am linking a video here to YT that shows the problem I'm having. I'm not new to CNC, I built my first two by hand from scratch and wanted a nicer, larger platform. I bought this one at auction and have loved it for the last 3 months. But I was running small size jobs. no problems. But now that I'm wanting to run a full sheet, it seems to be "stalling". I don't know what's really happening honestly, but it just makes a bad sound as soon as it tries to get to it's max move speed. I've tried changing speeds, I've checked for heat on the controllers, I've run it WITHOUT my dust collector, without the router running, nothing fixes it. It usually happens when I run an SBP, but I've gotten it to happen just when telling it through SB3 to move between coords at opposite ends of the table. The video shows it and you can hear it too! I'm hoping one of you all can tell me what I'm missing and what the problem could be. Also, and this will sound crazy, I'm also hoping one of you can tell me what kind of machine I have. I believe it to be a PRT. The control board says it's a PRT, but there's a white sticker that has PRS at the beginning? Thoughts?

I will reply to this threat with a link to the video in YT as soon as the upload finishes. Thanks!

[mercuru049]

https://youtu.be/RW6EKpfryoo

[Tom Bachman]

Your machine is a PRT looks a lot like mine. It also sports an upgraded board to a V4.17. Looks just like the one I just installed on my PRT. Other than that I can't help you much.

[mercuru049]

Your machine is a PRT looks a lot like mine. It also sports an upgraded board to a V4.17. Looks just like the one I just installed on my PRT. Other than that I can't help you much.

Thank you very much for the information on my machine! Now I'm hoping someone can tell me what the issue is.

[bleeth]

When you first zero and you say it does fine actually it doesn't. The noise is too loud and sounds like you have a binding issue.
On a PRT there are several things that can cause that.:
1. Your springs are too tight.
2. your rails are not properly aligned.
3. One of your x motors is not running (Listen carefully when you turn it on-Do both x motors "clunk"? When they are on but at rest does one move more easily when trying to move it by hand than the other?) Do NOT push the gantry far or quickly when motors are on-you can blow a driver, but just shaking back and forth a bit will tell you since when on they don't move easily.)

You can only track this by going through all the physical set-up routines, from making sure everything is square and parallel to making sure your Y carriage and x car are riding properly on the rails It doesn't take much.

Make sure you have properly tightened the springs. It should just be a couple turns past proper seating. Make sure when you move the gantry or the x car that the x wheels and y wheels stay properly seated on the rails and all roll smoothly. Check your pinion gears for wear. Make sure you have appropriate grease on the racks-Not too much since it gets messy quick. The manual on the PRT is pretty good about explaining all the set up needs. Go through it again. You may be surprised at how much a small issue in rail misalignment or incorrect motor spring adjustment can toss your operation down the drain.

I have a vague memory of hearing that movement notification alarm before-who did you get it from? In any event, once it is moved from one location to another everything needs to be rechecked to the nth degree for accuracy. These big "tinker toys" have tighter adjustment tolerances than some people think.

And yes-It is a PRT. The upgrade board was designed for a PRS frame but works fine (much better than original) on a PRT. The motors are the same and so can be controlled by the same board.

[Brady Watson]

The machine is a 3rd Generation PRT, also known as a 3G. The control box is considered a 4G, probably from a PRS machine.

The problem isn't anything to do with the machine. The problem is your computer. You showed a quick glance of your monitor in the video - and it showed multiple tabs of Chrome running & who knows what else. That's a no-no. The PC needs to be optimized to run the CNC because it is an extension of the controller itself. Anything that competes with SB3 needs to be shut down or culled from the PC, including: anti-virus, background services like Windows Update, change the power settings for everything to stay on, including advanced settings like 'USB Selective Suspend' to off. NOTHING besides SB3 should be running.

If you need to browse the net or use something else on the PC, you either have to stop running the machine or just use your phone or tablet. If the PC can't output the pulse stream to the control box cleanly without being interrupted, it will choke and stall.

You may also have to turn down your jog speed (JS) to something more reasonable like 6"/sec - as top speed is reliant on clean communication from the PC and every PC is different. I've had some that were able to jog up to 20"/sec, while others will only do 6"/sec.

Good luck!

-B

[bleeth]

Quick eyes Brady!
I also would recommend stripping that computer ala "Black Viper" (do a web search) and making sure your screen saver is off, automatic updates is off, no anti-virus, etc.
When I upgraded my old PRT with a custom 4g controller jog hit 12 ips. Cut max for plywood, etc. was 4ips.

[mercuru049]

When you first zero and you say it does fine actually it doesn't. The noise is too loud and sounds like you have a binding issue.
On a PRT there are several things that can cause that.:
1. Your springs are too tight.
2. your rails are not properly aligned.
3. One of your x motors is not running (Listen carefully when you turn it on-Do both x motors "clunk"? When they are on but at rest does one move more easily when trying to move it by hand than the other?) Do NOT push the gantry far or quickly when motors are on-you can blow a driver, but just shaking back and forth a bit will tell you since when on they don't move easily.)

You can only track this by going through all the physical set-up routines, from making sure everything is square and parallel to making sure your Y carriage and x car are riding properly on the rails It doesn't take much.

Make sure you have properly tightened the springs. It should just be a couple turns past proper seating. Make sure when you move the gantry or the x car that the x wheels and y wheels stay properly seated on the rails and all roll smoothly. Check your pinion gears for wear. Make sure you have appropriate grease on the racks-Not too much since it gets messy quick. The manual on the PRT is pretty good about explaining all the set up needs. Go through it again. You may be surprised at how much a small issue in rail misalignment or incorrect motor spring adjustment can toss your operation down the drain.

I have a vague memory of hearing that movement notification alarm before-who did you get it from? In any event, once it is moved from one location to another everything needs to be rechecked to the nth degree for accuracy. These big "tinker toys" have tighter adjustment tolerances than some people think.

And yes-It is a PRT. The upgrade board was designed for a PRS frame but works fine (much better than original) on a PRT. The motors are the same and so can be controlled by the same board.

Thank you for the information. I just went through a "rebuild" of sorts. I noticed I wasn't getting square cuts. I basically rebuilt/realigned it. Now I'm getting perfectly square cuts. VBearings are perfectly on rails, everything is snug. Springs aren't too tight (at least to my definition). Both motors are working properly. It's hard to tell if they both "Chunk", but I did check by hand and they both have holding torque.

[mercuru049]

The machine is a 3rd Generation PRT, also known as a 3G. The control box is considered a 4G, probably from a PRS machine.

The problem isn't anything to do with the machine. The problem is your computer. You showed a quick glance of your monitor in the video - and it showed multiple tabs of Chrome running & who knows what else. That's a no-no. The PC needs to be optimized to run the CNC because it is an extension of the controller itself. Anything that competes with SB3 needs to be shut down or culled from the PC, including: anti-virus, background services like Windows Update, change the power settings for everything to stay on, including advanced settings like 'USB Selective Suspend' to off. NOTHING besides SB3 should be running.

If you need to browse the net or use something else on the PC, you either have to stop running the machine or just use your phone or tablet. If the PC can't output the pulse stream to the control box cleanly without being interrupted, it will choke and stall.

You may also have to turn down your jog speed (JS) to something more reasonable like 6"/sec - as top speed is reliant on clean communication from the PC and every PC is different. I've had some that were able to jog up to 20"/sec, while others will only do 6"/sec.

Good luck!

-B

I will go through and strip down ALL un necessary services and run another test this evening to see if gets any better. Thank You.

[EricSchimel]

You can check the speed of communication from your computer to the control box by doing this:

Jox 12-24" on X and type in "UD" into the SB3 control software. You'll see a blue screen with a bunch of information on it. Near the bottom is transmission time, that should be at or under 20ms. I'd run it a couple of times too. Try jogging in one axis, then two, then three.

This will help you determine the quality of your USB communication. I've found them very different between computers. The machine I have now is around 16ms and it's rock solid reliable, even when jogging at over 20 ips (your machine won't be able to go that fast though..)

[pro70z28]

Quick eyes Brady!
I also would recommend stripping that computer ala "Black Viper" (do a web search) and making sure your screen saver is off, automatic updates is off, no anti-virus, etc.
When I upgraded my old PRT with a custom 4g controller jog hit 12 ips. Cut max for plywood, etc. was 4ips.

I learned the hard way about screen saver and sleep mode. Puts the shopbot to sleep mid job also.

[mercuru049]

Since I now know I have a PRT-3g, but I have a PRS Control Box, when I install the SB3 software, what should I pick for it to use a configuration file? I plan to do a complete reinstall on machine and want to make sure I'm setting it up right.

Thanks!

[jerry_stanek]

Also what version of Shopbot software are you running

[mercuru049]

Also what version of Shopbot software are you running

SB3. I downloaded the newest software when I set it up. But I remember when I was going through the setup it wanted me to select the machine I had. I believe I had the right one, but then I also remember something not being right and me reloading it. I think it auto selected that time? So this begs 2 questions. 1. Which machine should I tell it I have? PRT or PRS? It's a PRT machine with a PRS controller I believe. Also, I notice that not matter what I set the Speed settings to, it doesn't seem to adjust the speed at which the machine moves?

[Brady Watson]

Since I now know I have a PRT-3g, but I have a PRS Control Box, when I install the SB3 software, what should I pick for it to use a configuration file? I plan to do a complete reinstall on machine and want to make sure I'm setting it up right.

Thanks!

You should be running v3.6.46 (http://www.shopbottools.com/files/Setup_sb3_6_46.exe) with a 4G control on that tool. If input 4/e-stop light flashes invert the e-stop from normally closed to normally open with the VN command. Be 100% SURE to run UI and install the firmware that matches the v3.6.46 front end or it won't run right. You should pick the config file that matches a PRT 4G with old stop (if that option is there & you have a normally open e-stop). You must install the firmware any time you change a version of SB3.

FYI - Factory spec on the turnbuckle/springs is 3.5 turns out from when the spring starts to expand. That is the correct tension. Consider making new mounts for the X&Y axes as those angle iron ones suck. 1/4 or 3/8" aluminum ones will be fine & will make the tool tighter and less sloppy when it comes to gear mesh - plus pinions will last longer. I would go so far as to make PRS style mounts where there is no spring and the flat mounting plate is just rammed up into the rack and tightened down with at least 2 bolts. This involves some fabbing and drilling etc. I believe the springs were present to make up for sloppy manufacturing, steel tolerance and slip-shod assembly on the customer's end. You can try calling SB to see if they still make the PRT 4G/Alpha spec motor mounts for the X&Y if you don't want to fab anything. They are way better than the ones you have.

Also...Gear racks must be lubricated with grease...not WD40, not silicone spray - actual grease - any you have is fine. A small DOT is all that is needed every 6" or so and run it back and forth - and wipe it down & off anything that doesn't have teeth. Steel on steel without lube will smoke a set of pinions in only a few weeks - and while they're consumables on the machine, they aren't as cheap as they used to be. Worn pinions will kill the edge quality on plastics, aluminum and any other dense material.

-B

[Brady Watson]

You can get an idea of the 4G/Alpha spec XY mounts I mentioned looking at the first pic in this thread: http://www.talkshopbot.com/forum/showthread.php?22359-PRT-Alpha-48-x-96-with-custom-steel-table

Also note the gantry is PRTAlpha spec, which is essentially identical to the 4G (no more unistrut) except for the stepper motors.

-B

[mercuru049]

You should be running v3.6.46 (http://www.shopbottools.com/files/Setup_sb3_6_46.exe) with a 4G control on that tool. If input 4/e-stop light flashes invert the e-stop from normally closed to normally open with the VN command. Be 100% SURE to run UI and install the firmware that matches the v3.6.46 front end or it won't run right. You should pick the config file that matches a PRT 4G with old stop (if that option is there & you have a normally open e-stop). You must install the firmware any time you change a version of SB3.

FYI - Factory spec on the turnbuckle/springs is 3.5 turns out from when the spring starts to expand. That is the correct tension. Consider making new mounts for the X&Y axes as those angle iron ones suck. 1/4 or 3/8" aluminum ones will be fine & will make the tool tighter and less sloppy when it comes to gear mesh - plus pinions will last longer. I would go so far as to make PRS style mounts where there is no spring and the flat mounting plate is just rammed up into the rack and tightened down with at least 2 bolts. This involves some fabbing and drilling etc. I believe the springs were present to make up for sloppy manufacturing, steel tolerance and slip-shod assembly on the customer's end. You can try calling SB to see if they still make the PRT 4G/Alpha spec motor mounts for the X&Y if you don't want to fab anything. They are way better than the ones you have.

Also...Gear racks must be lubricated with grease...not WD40, not silicone spray - actual grease - any you have is fine. A small DOT is all that is needed every 6" or so and run it back and forth - and wipe it down & off anything that doesn't have teeth. Steel on steel without lube will smoke a set of pinions in only a few weeks - and while they're consumables on the machine, they aren't as cheap as they used to be. Worn pinions will kill the edge quality on plastics, aluminum and any other dense material.

-B

Great information here, thank you!

[mercuru049]

You should be running v3.6.46 (http://www.shopbottools.com/files/Setup_sb3_6_46.exe) with a 4G control on that tool. If input 4/e-stop light flashes invert the e-stop from normally closed to normally open with the VN command. Be 100% SURE to run UI and install the firmware that matches the v3.6.46 front end or it won't run right. You should pick the config file that matches a PRT 4G with old stop (if that option is there & you have a normally open e-stop). You must install the firmware any time you change a version of SB3.

FYI - Factory spec on the turnbuckle/springs is 3.5 turns out from when the spring starts to expand. That is the correct tension. Consider making new mounts for the X&Y axes as those angle iron ones suck. 1/4 or 3/8" aluminum ones will be fine & will make the tool tighter and less sloppy when it comes to gear mesh - plus pinions will last longer. I would go so far as to make PRS style mounts where there is no spring and the flat mounting plate is just rammed up into the rack and tightened down with at least 2 bolts. This involves some fabbing and drilling etc. I believe the springs were present to make up for sloppy manufacturing, steel tolerance and slip-shod assembly on the customer's end. You can try calling SB to see if they still make the PRT 4G/Alpha spec motor mounts for the X&Y if you don't want to fab anything. They are way better than the ones you have.

Also...Gear racks must be lubricated with grease...not WD40, not silicone spray - actual grease - any you have is fine. A small DOT is all that is needed every 6" or so and run it back and forth - and wipe it down & off anything that doesn't have teeth. Steel on steel without lube will smoke a set of pinions in only a few weeks - and while they're consumables on the machine, they aren't as cheap as they used to be. Worn pinions will kill the edge quality on plastics, aluminum and any other dense material.

-B

When I installed the SB3 software the first time, I remember that it did update some firmware, it did at least one separate download for firmware. Yes, my EStop is reversed. I didn't know how to reverse it in the sofware and basically just depressed the EStop to get the machine running ( I know I know, shame on me ). Will be working on some of what you have said here when I get home. Hoping to not have to mahine new brackets right away though, but I appreciate the upgrade advice. Will only dot hat if I have to. Also appreciate the 3.5 turns, now I can have a better idea if I'm tensioned properly.

[Brady Watson]

The firmware is never automatically installed. You are probably thinking of the USB drivers. You *must* install it manually. It won't hurt to load it again anyway via UI command.

Smart thinking with the estop. Just type in the VN command and change the estop from NC to NO. There are actually 4 wires on the estop (2 are hidden because they were cut back) - you *could* rewire it NC by just wiring the 2 that are hidden - your choice.

-B

[mercuru049]

You should be running v3.6.46 (http://www.shopbottools.com/files/Setup_sb3_6_46.exe) with a 4G control on that tool. If input 4/e-stop light flashes invert the e-stop from normally closed to normally open with the VN command. Be 100% SURE to run UI and install the firmware that matches the v3.6.46 front end or it won't run right. You should pick the config file that matches a PRT 4G with old stop (if that option is there & you have a normally open e-stop). You must install the firmware any time you change a version of SB3.

FYI - Factory spec on the turnbuckle/springs is 3.5 turns out from when the spring starts to expand. That is the correct tension. Consider making new mounts for the X&Y axes as those angle iron ones suck. 1/4 or 3/8" aluminum ones will be fine & will make the tool tighter and less sloppy when it comes to gear mesh - plus pinions will last longer. I would go so far as to make PRS style mounts where there is no spring and the flat mounting plate is just rammed up into the rack and tightened down with at least 2 bolts. This involves some fabbing and drilling etc. I believe the springs were present to make up for sloppy manufacturing, steel tolerance and slip-shod assembly on the customer's end. You can try calling SB to see if they still make the PRT 4G/Alpha spec motor mounts for the X&Y if you don't want to fab anything. They are way better than the ones you have.

Also...Gear racks must be lubricated with grease...not WD40, not silicone spray - actual grease - any you have is fine. A small DOT is all that is needed every 6" or so and run it back and forth - and wipe it down & off anything that doesn't have teeth. Steel on steel without lube will smoke a set of pinions in only a few weeks - and while they're consumables on the machine, they aren't as cheap as they used to be. Worn pinions will kill the edge quality on plastics, aluminum and any other dense material.

-B

So, I tried this and no dice. I've installed/uninstalled a bunch trying to get config to work. The closest I've gotten is when it loads, it ays "Shopbot seems present but is not responding...." and wants me to keep trying other ports. It's set to correc tport and I've let it search too. I pulled that and put the newest version of the software up and it runs fine (except for stalling) Also noticed though that on the newest version of software, it doesn't seem to matter what I set the speed to, it has no effect. Thoughts/

[jerry_stanek]

With the newest software did you reload the firmware

[mercuru049]

Yes, should I not?

[mercuru049]

Ok, just reinstalled new software. Did not update firmware and it would not work. Updated firmware and it works. But I'm wondering if I'm using wrong software. Other poster said I should be on 3.6.46.

Intereeting though. Ran my test file, it was finally slower! And didn't stall on long run! I think the speed was overloading the motors...

[mercuru049]

Ok. The stalling has STOPPED! The problem is that no matter what I set the speed settings to in the software it was apparently trying to use 30 (or 1800ipm). Once I reloaded everything, i set it to 10 (600ipm) and the problem is fixed. But I took a video of the sounds its making and I'm hoping one of you can confirm these sounds to be normal. Seriously, thank you all for the suggestions and help, even though a lot of the suggestions turned out to not be the problem, I know my setup is better for having had this conversation.

https://www.youtube.com/watch?v=wx7ZFarQcK4

[coryatjohn]

I suggest instead of running circles, you run each axis by itself to isolate which one is making the noise. It doesn't sound too bad though. It might be normal for your machine.

[jerry_stanek]

That is what my PRS sounds like when cutting circles. You may want to slow it down just a little yet

[mercuru049]

Thank You All For the Help! I'm up/running great now.