CoreXY belt, tightening from either side?

  • Hypercube Evolution has tightening screws on both sides of each of the two CoreXY belts (picture below, not mine). Does it matter on what side a CoreXY belt is tightened?

    (I want to simplify the carriage and have tightening screws on one side only. I understand that I will have only half of the tightening range but am not sure if I am going to loose an also a geometry alignment degree or freedom).


  • Pulling a belt tight is pulling it tight. It doesn't matter which side you pull it from. You do have to be able to tighten both belts separately.

    You appear to be using steel core belts. That's a bad idea, unless you're using very large pulleys (30mm diameter or more, including the drive pulley). The core wires will quickly break from flexing too much and then the polyurethane belt will stretch over the wires. You'll have all sorts of weird print artifacts, and you'll find the belts loosening and you'll keep tightening them over and over until you run out of adjustment range.

    Get some glass core belts. They don't stretch enough to cause any print defects and they don't have problems on typical 3D printer-size pulleys.

    You might find some useful info here:

  • @mrehorstdmd said in CoreXY belt, tightening from either side?:

    will quickly break

    I am hard headed and decided I'd use steel anyway, despite the advice of others, on a CoreXY. Didn't even get the printer fully commissioned (maybe 1 hour of belt movement, maybe less) before one of the belts broke. I'm now on glass.

  • Thanks @mrehorstdmd. Side doesn't matter then, that's good.

    As for the belt, the picture is from the internet as stated, on my printer which uses 16T motor pulleys I am using a standard Gates belt and am very happy with it. I don't think metal core belt would be able to handle it.

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