# New Shapeoko Upgrade Day! Buh-Bye Belt!



## Randy (Feb 9, 2020)

I know there's a few guys on here with the Shapeoko so I figured I'd share.

It's a great machine that I've gotten a lot of use out of but the Z axis has been an issue since day one, and that seems to be a common experience. I get a lot of skips or slips, and it's easily bound up because the inside traps sawdust easily and it binds up the wheels.

Because the G code usually sends a single up or down coordinate, any skip or skip means the unit can either dive too far or not extract fully and cuts where it's not supposed to. It got to the point I was partially disassembling after every use and cleaning the wheels or tensioning the belt to keep from ruining a project.

I was googling Z upgrades literally just as this guy got posted and it looked like exactly what I was after at a reasonable price.

http://rover.ebay.com/rover/1/711-5...0001&campid=5338014327&icep_item=233480338446

I know Carbide has the HD-Z but that's too much ($400) and they've got a dumbed down version on the way but I needed this fixed ASAP and the limited supply of these seemed like it was worth a shot, especially with the return policy.

Anyway, I ordered it and it came in yesterday. Installation took way longer than expected but that's mostly my fault. Directions are okay but left some things out. I spoke to the designer and he clarified a few things, so installation worked out alright in the end.

Haven't gotten a chance to use it yet other than tramming but moves nicely and accurately when homing and returning to zero. The Z motor sounds noticeably less strained.


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## IGC (Feb 9, 2020)

Looks like a switch from the original belt drive to a direct lead screw? Did you need to re-flash the arduino firmware or is there a setting in GRBL or Mach3 ?


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## DickyTripleD (Feb 9, 2020)

IGC said:


> Looks like a switch from the original belt drive to a direct lead screw? Did you need to re-flash the arduino firmware or is there a setting in GRBL or Mach3 ?


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## Randy (Feb 9, 2020)

IGC said:


> Looks like a switch from the original belt drive to a direct lead screw? Did you need to re-flash the arduino firmware or is there a setting in GRBL or Mach3 ?



Basically, yeah. Same motor just mounted on top, bottom belt tensioner repurposed as a lower guide for lead screw, then a piece screwed to the sliding plate using existing holes with a brass ferrule that mates with the lead screw.

Directions include two small codes you punch into MDI in Carbide Motion and directions on how to reverse it if you so choose. That part is super simple.

I'll report back when I get to actually cut something. Returning to home and to zero back and forth seemed to be as good as stock.


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## Randy (Feb 9, 2020)

Main thing that ate up time was my fault, I dropped a screw between the 'X' belt bearings and it was almost impossible to get out.

Second install issue was the drag chain mount. There's no mention of it in the directions but it doesn't work with the mount in the stock location, there's an extra piece to use as a 'stand off' and you need non-stock, longer screws to attach it. I was able to work around that by bending the mount a little and that seemed to work okay. Hopefully he adds that to the directions and includes the longer screws in future versions.

Overall I'm digging the design and the fact it uses 99% unmodified stock parts and stuff from the kit. If you know what you're doing it's probably a 10 minute job.


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## IGC (Feb 10, 2020)

@Randy , 
Lately I'v been questioning how well the belt driven cnc routers work under the load and potential problems if using them . Seems like belts are fairly common use for this type of equiptment. I'v been contemplating a belt driven design anti - skip and foreign debris optimal. 
Do you have a dust shoe?


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## cip 123 (Feb 10, 2020)

IGC said:


> @Randy ,
> Lately I'v been questioning how well the belt driven cnc routers work under the load and potential problems if using them . Seems like belts are fairly common use for this type of equiptment. I'v been contemplating a belt driven design anti - skip and foreign debris optimal.
> Do you have a dust shoe?


From what I've heard Belts are generally less accurate than Lead Screws, I'm not particularly experienced in the components of CNC, but hearing this from a few people was enough for me to go for a screw driven machine.


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## IGC (Feb 10, 2020)

cip 123 said:


> From what I've heard Belts are generally less accurate than Lead Screws, I'm not particularly experienced in the components of CNC, but hearing this from a few people was enough for me to go for a screw driven machine.



Thanks for the insight.

You check out the Shapoko xxl review and it seems pretty good, at least for wood cutting, it's what got me considering belts. 
https://www.matterhackers.com/store/l/carbide-3d-shapeoko-xxl-cnc-router-kit/sk/MH3XDXDJ



Btw @Randy yes or no, did yoy notice skipping before the foreign debris ?


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## MikeNeal (Feb 10, 2020)

cip 123 said:


> From what I've heard Belts are generally less accurate than Lead Screws, I'm not particularly experienced in the components of CNC, but hearing this from a few people was enough for me to go for a screw driven machine.



I've got my belt driven shapeoko 3 very accurate +-.005", which honestly is good enough for anything wood. it has taken me a ton of time to get this repeatable though. I've been working at it for the better part of 2 years.

As for belts vs screws - generally its screws for accuracy, belts for speed. If you try and move a screw design at the speeds you can move a belt, you will get screw whip and loose accuracy significantly.


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## Randy (Feb 10, 2020)

IGC said:


> @Randy ,
> Lately I'v been questioning how well the belt driven cnc routers work under the load and potential problems if using them . Seems like belts are fairly common use for this type of equiptment. I'v been contemplating a belt driven design anti - skip and foreign debris optimal.
> Do you have a dust shoe?



I think @MikeNeal covered it pretty well. I'm getting within .1mm accuracy on my X and Y motion consistently. Even though they're belts, they're kevlar reinforced and don't flex to the point of losing accuracy very easily, if at all. The Z is a little different between the enclosed space, the belt doesn't seem reinforced, its especially hard to adjust tension because of the confined space and overall design, and the nature of Z coordinates in general.

I'm not running a dust collector currently, partially because I previously had concerns about it getting in the way (I'm less worried about that now) and mostly because the wiring in my shop has limited amperage supply, and overloading the circuit can cause the controller to lose G code lines in my experience. I tried running a ShopVac off the same outlet a few times and the machine lost where it was on the piece. If you've got a better supply or run off a different circuit, I guess that likely isn't an issue.

The wind generated from the machine repels sawdust pretty well, and then I use a brush between procedures or even during. I'm sure the lack of dust collection has something to do with my buildup but it specifically happens during really deep cuts that would likely make the dust shoe setup hard to use.


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## MikeNeal (Feb 10, 2020)

Randy said:


> I think @MikeNeal covered it pretty well. I'm getting within .1mm accuracy on my X and Y motion consistently. Even though they're belts, they're kevlar reinforced and don't flex to the point of losing accuracy very easily, if at all. The Z is a little different between the enclosed space, the belt doesn't seem reinforced, its especially hard to adjust tension because of the confined space and overall design, and the nature of Z coordinates in general.
> 
> I'm not running a dust collector currently, partially because I previously had concerns about it getting in the way (I'm less worried about that now) and mostly because the wiring in my shop has limited amperage supply, and overloading the circuit can cause the controller to lose G code lines in my experience. I tried running a ShopVac off the same outlet a few times and the machine lost where it was on the piece. If you've got a better supply or run off a different circuit, I guess that likely isn't an issue.
> 
> The wind generated from the machine repels sawdust pretty well, and then I use a brush between procedures or even during. I'm sure the lack of dust collection has something to do with my buildup but it specifically happens during really deep cuts that would likely make the dust shoe setup hard to use.



one of the things we did is run a dedicated outlet on its own breaker for the cnc machine. i had the same issue of skipping a step here or there.


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## IGC (Feb 11, 2020)

@Randy seems like a dust shoe would also be more load for the -z- to move around. And you don't want to stand there holding a shop vac hose right next to the cutter every move it makes.


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## Bobo (Feb 15, 2020)

MikeNeal said:


> I've got my belt driven shapeoko 3 very accurate +-.005", which honestly is good enough for anything wood. it has taken me a ton of time to get this repeatable though. I've been working at it for the better part of 2 years.
> 
> As for belts vs screws - generally its screws for accuracy, belts for speed. If you try and move a screw design at the speeds you can move a belt, you will get screw whip and loose accuracy significantly.



Can you give a summary of why it takes so long to get acceptable accuracy? If it's not the belts, is it something else about that specific machine? Or is it just in the programming? These are questions from a cnc noob btw.

Sorry if this is somewhat of a highjack Randy


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## Randy (Feb 15, 2020)

IGC said:


> @Randy seems like a dust shoe would also be more load for the -z- to move around. And you don't want to stand there holding a shop vac hose right next to the cutter every move it makes.



Most of the popular dust shoes attach to the carriage at the back, not necessarily the part that raises and lowers with the Z. You manually raise and lower them to match with the height of the workpiece, which is probably fine for a lot of things but when I'm cutting 1.75"+ deep and it's at the extreme end of what the cutter will do, I'm weary of any potential drag over the surface. I'd also imagine it's only marginally effective when you're cutting out contours like this and the gap is so narrow.






Bobo said:


> Can you give a summary of why it takes so long to get acceptable accuracy? If it's not the belts, is it something else about that specific machine? Or is it just in the programming? These are questions from a cnc noob btw.
> 
> Sorry if this is somewhat of a highjack Randy



No hijack, I think this is the perfect place to ask.

Because of the way the machine goes together, you have to consider how square you have the frame of the machine, how well adjusted the V wheels are into their channels (no wobble), how straight and square the spindle is to the work surface, how level the work surface is and how tight your belts are.

The two year number is potentially how long something like that can take from trial and error, but if you're focused specifically on taking dial indicator readings and making adjustments, I'm sure you can do it in a few hours.

I was getting what I'd consider acceptable results after my initial assembly (I'm sure that's most people's experience, Mike included), so it's not like the machine is especially in need of fine tuning to work; if anything, quite the opposite. I only started needing to fine tune adjustments after my belts initially "broke in" (I needed to tighten my X belt by a tooth or two because it was skipping under load), after I added a spoilboard (had to resurface it because of inconsistencies in thickness and how well seated it was), and after initial wear on the Z axis delrin V wheels (they started to clunk back and forth under load, just needed to adjust the asymmetrical nuts to seat the wheels tighter in the channel).

The machine worked fine up until that stuff, which came on after using to for a couple months. Since then, it's needed very little adjustment besides maintenance for over a year. It always helps to test on scrap and monitor what the machine is doing, as opposed to bolting in an expensive blank and walking away.

As far as accuracy, I did a personalized brass plated sign for somebody where I engraved it with their name. The plate was .063" thick and I had to cut a max of halfway through it's thickness without cutting too deep or to shallow (so, .0315" with a maximum deviation of maybe .015"), across about 30" wide and 8" tall, and it did it perfectly.


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## IGC (Feb 16, 2020)

Randy said:


> Most of the popular dust shoes attach to the carriage at the back, not necessarily the part that raises and lowers with the Z. You manually raise and lower them to match with the height of the workpiece, which is probably fine for a lot of things but when I'm cutting 1.75"+ deep and it's at the extreme end of what the cutter will do, I'm weary of any potential drag over the surface. I'd also imagine it's only marginally effective when you're cutting out contours like this and the gap is so narrow.
> 
> View attachment 77545
> 
> ...





.015 over a 30-inch span is pretty darn acceptable for this type of machine/ guitar cnc. I've been checking out those Delrin V wheels and their eccentric spacers online, interesting to hear about possible issues with them. I guess you could use use the eccentric spacers to tram the gantry?

I also hear that with belt driven the belts can stretch at higher feeds if you don't ease your moves...accel and decell


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## Randy (Feb 16, 2020)

IGC said:


> I guess you could use use the eccentric spacers to tram the gantry?



I suppose, although you can tram it by hand when you have the controller powered off anyway. My guess is that they're just there to adjust for wear on the wheels over time.

Speaking of Z upgrades, Carbide released this and surprise, it sold out in hours (minutes?). $250, which is better than the HDZ ($500) but not as inexpensive as this thing. Design looks similar but looks like the whole piece got redesigned. The big upgrade on the Z-plus over the True-Z is the elimination of the wheels, but how necessary that is, I won't know until I make some cuts.

https://shop.carbide3d.com/collections/accessories/products/shapeoko-z-plus?variant=31524471144509


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## IGC (Feb 17, 2020)

Randy said:


> I suppose, although you can tram it by hand when you have the controller powered off anyway. My guess is that they're just there to adjust for wear on the wheels over time.
> 
> Speaking of Z upgrades, Carbide released this and surprise, it sold out in hours (minutes?). $250, which is better than the HDZ ($500) but not as inexpensive as this thing. Design looks similar but looks like the whole piece got redesigned. The big upgrade on the Z-plus over the True-Z is the elimination of the wheels, but how necessary that is, I won't know until I make some cuts.
> 
> https://shop.carbide3d.com/collections/accessories/products/shapeoko-z-plus?variant=31524471144509




Seems like a good upgrade, with the ball bearing guide rails and lead screw. Are the original mounting plates aluminum? The new plates are 1/4 steel could this be more weight for -x- motor to pull?


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## LiveOVErdrive (Feb 17, 2020)

Oh holy crap I need this so bad.


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## Randy (Feb 17, 2020)

IGC said:


> Seems like a good upgrade, with the ball bearing guide rails and lead screw. Are the original mounting plates aluminum? The new plates are 1/4 steel could this be more weight for -x- motor to pull?



Old ones are also steel, somewhere in the same thickness range so probably not much more weight on that end. Old one has a lot of empty space though, and this upgrade kit is mostly ABS, I'm not sure how much beef is in the Z-plus.


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## LiveOVErdrive (Feb 18, 2020)

What happens if you crash your z axis with a screw drive? Does something have to break? Belt slippage is a nice failsafe against damage when you move your axis where it oughtnt go.


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## Randy (Feb 18, 2020)

You're right. Probably more prone to break things yeah, but my X and Y belts/motors usually do all the binding, my Z seems to drill right fuckin through whatever it wants as is anyway  We'll see how this goes, this setup might be the most practical balance of both.

I was thinking my next upgrade would be all lead screw around the same size, but now I'm thinking about that Openbuilds 60" x 40" belt driven rig for doing neck thrus and basses.


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## Randy (Mar 22, 2020)

Update! Finally did some cutting.

The good:

Z seems to be accurate and sturdy. I was worried the change and a small code to the controller wouldn't be enough for a full project to be accurate but looks like it did the trick.

The bad:

The Z plunge and retract are still random. If it's ramping, it's accurate as hell. If it's retracting to go to next step, it's hit or Miss if it will retract fully.

Likewise, I contoured a body and the way Fusion programs multiple depths is to retract full, then back down to next coordinate. The heights it would go up or down to were like full random. Three passes too shallow, then it decided to route the correct depth all at once and cut 3/4" deep in one pass. Then the next pass it tried to bury the whole bit into the spoilboard.

The neck came out a lot better but also wanted to go straight into the spoilboard during the contour procedure.

Project is still useable since it's one for myself and it's gonna be solid finished but this is the kinda shit you don't want happing with a $300 koa top.


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## Randy (Mar 22, 2020)

I'm starting to think this is what I said earlier. The draw from the router is fucking with the controller voltage and you get random misses. I'm going to try a test with no wood and without the spindle on to see how the controller works with no other load on it.


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## Soya (Mar 23, 2020)

Could you run a multimeter on the controller while it's running to monitor voltage and current to see if it dips when it misses?


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## LiveOVErdrive (Mar 23, 2020)

Randy said:


> I'm starting to think this is what I said earlier. The draw from the router is fucking with the controller voltage and you get random misses. I'm going to try a test with no wood and without the spindle on to see how the controller works with no other load on it.



Oh that's an interesting idea. Maybe you can run them on separate circuits or something.

I was going to say that I've never had my z axis plunge do random distances. The calibration frequently gets off when the belt slips while plunging into too-hard material (or any material. The center of the bit doesn't cut well. Ramping is good), but other than that it works fine.


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## Randy (Mar 23, 2020)

Soya said:


> Could you run a multimeter on the controller while it's running to monitor voltage and current to see if it dips when it misses?



Good idea. I'll add that to my trouble shooting list. Thanks!



LiveOVErdrive said:


> Oh that's an interesting idea. Maybe you can run them on separate circuits or something.
> 
> I was going to say that I've never had my z axis plunge do random distances. The calibration frequently gets off when the belt slips while plunging into too-hard material (or any material. The center of the bit doesn't cut well. Ramping is good), but other than that it works fine.



Yeah, i think its specific to my machine. I know my wires into the controller were always a little sketchy (tight and easy to pull out).

I also am running off a single line clear on the other side of the building, and that supplies 6 shop lights and all my machines, and then my controller, AND spindle are running off the same cheesy power strip. I rewired it last year with heavier gauge wire and redid all my connections but before that, my router or my dehumidifier would make the lights flicker. So power supply is definitely a weak point.

I'll start with running the file with nothing else and see how it behaves. If its better, I'll see what I have to do to run current to this end of the building and get the spindle on a separate circuit.

Anyway, I shot some video when it was behaving so you can see the bolt ons in action.


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## Randy (Mar 23, 2020)

Ran the test.

Dial gauge got stuck in a gouge in my spoilboard in the first ten seconds, so I couldn't confirm any depths but observationally it looks like it did the exact same thing, which is probably what I least expected.

It trammed perfectly X and Y, first depth looked right. Then the next three or four passes, it looked like it was getting shallower and shallower. You could actually see while it was lowering, it was stop in the middle and then begin lowering again. No noise look it was binding or straining, just stops. Then by the fourth or fifth pass, it drops down around 3/4" and then next pass it dropped to right about the spoilboard. I got out the body that it cut through yesterday and confirmed it bottomed out just about exactly where it did yesterday.

So yeah, I thought it was having a brain fart and the Z depths were somewhat random but no, under no load it ended up at the same depths on the same passes. I thought maybe there was a problem with the code from Fusion, so I loaded it into nc viewer and it tracked perfectly.

So at least that answers some questions. I'm currently suspecting my controller or wiring to it, maybe I'm in need of a firmware update or the processes I'm sending from Fusion aren't cooperating with GRBL for multiple depth commands.

I know early on I was having an issue cutting guitar bodies because the withdraw height it wanted versus the height of the body plus the spoilboard caused the machine to auto dive and all my heights thereafter were relative to wherever the limit switch dropped it. I raised my spindle to offset the height of the spoilboard and that fixed it. I'm wondering if when it's withdrawing between passes if it's hitting the limit switch.


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## Randy (Mar 24, 2020)

Incremental update.

Cleaned the controller and trammed/homed the machine a few times and noticed I was getting funny slipping in the Z. I checked and it ends up the collar between the motor and the lead screw was slipped, so I moved it back to the flat spot and tightened it down.

Went back to my old models, removed any rapid extracts and switched to 'keep tool down' for everything, ran a few today and had near 100% success with some semi complicated cavities. Only hiccup was my cavity routing too deep on first pass but I think I set my stock height wrong.


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