I guessed wrong on guitar tuning

I guess I didn’t tune to the right guitar string. I have now destroyed every bit I own, snapped one belt which in turn caused the machine to eat the other belt, burned through a butt load of MDF, wasted time and money to get not even the test carve to come out correctly. Expletive, expletive, expletive, set it on fire!!!
I have torqued, tightened, squared even piece of this thing to no avail.

I had a snapped belt at one point, and found that it was due to a GT2 pull that slipped a bit on the stepper motor shaft and was rubbing. I didn’t see it until it snapped. Could this be what caused the belt to snap?

I do “tune” mine like a guitar string and, just not a high pitched one.

dude it says “loose guitar string”, ofcorse it’s going to break if you over tighten it

just snapped a belt on mine last night. i dont feel the belts were over tight at all. i did however notice they had some fraying so maybe the pulleys werent lined up properly, or maybe they are just shitty belts

dont feel to bad ive had my machine for a month and a half and have yet to cut anything cleanly. ive wasted so much good wood its not even funny. cant count how many times id get 90% through a 4 hour project and watch the machine just go haywire and cut a 1/2 groove across the board for no apparent reason. nice

It was migrating during the cut, so I was told not tight enough…

You might want to consider sourcing belts from a company which specializes in them — while the prices are markedly higher at SDP-SI, the quality is supposed to be much better than inexpensive belts from overseas:


I’m noticing this is a consistent issue…how about kevlar reinforced belts… Inventables?

No problems here with belts.

the only problem i have had is i keep loosing steps while cutting i at first though it was because my belt was not tight enough. after watching every thing closely i realized it was the pulley not staying on the shaft of the motors so i took them all off and ground flats on them no problem since.

If you haven’t seen it, check out the video I added on belt tensioning tips:


I like to tighten the belt so that the bolt just barely touches the plate, then I use an allen wrench to push the bolt through while I tighten the nut on the other side. That amount of tension has worked really well for me.

Hey @BadWolf,

You haven’t happened to have used a different USB cable have you? I swapped the stock one out at one point for a longer one and all of a sudden, my machine started having problems and doing weird things. Turns out it was a bad USB cable so I put the stock one back on and everything went back to cutting just fine.

Worth a try?

Hey im using the one that came with the machine but ill see if i can find a different one and try it out. Thanks for the suggestion

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I had my belts to tight at first as well. Since I play the flat top I cranked em down. Ummm bad comparison. I have found to adjust belts till I can’t quite squeeze a finger under ( between belt and rail ) and it snaps back when released. Like a loose guitar string. Next with machine ( off ) move x & y axis by hand. It should move freely with just moderate resistance. If it trries to bind or stick - readjust. This along with checking tightness of wheels before each cut has resulted many sucsessful carvings after some initial problems. Hope this helps :slight_smile: