I’ve run into a possible issue with my printer. When the printer is powered off & I move the printhead sometimes it feels “rough” rather than nice & smooth. I’m wondering if the belting has been damaged in some spots from when the printhead jammed into the frame for a couple of seconds before I managed to hit the power switch.
I’m looking for advice on the best quality belting to buy to replace the belts on my printer, and whether this is something I should do. For example, how can I test if the belts are damaged?
Just found something on Amazon: PU with steel core. I assume PU stands for PolyUrethane. Would this be a better option than fiberglass reinforced rubber?
Also, if I did replace the belts, does anyone have recommendations for replacing the brass crimped ends that hold the belts into the slots on my Ender 5?
Metal only bends so often and you get cracks, which overtime reduces the steel enforced belt to a bad quality rubber belt. Just think about cables in there insulation. This is exactly the same just in rubber form and with far more stress (constant pulling and bending) on a thin layer of metal strands.
Metal is bending slowly. When you move a belt fast around a pulley, it simply wont stay on the pulley’s backside like a normal belt would do.
Before the 180° turn is complete the belt simply takes off and goes straight around 45° before bending again finishing the full 180 turn. The return way of the belt is kind of egg shaped on that side. Once you stop every thing looks kind of ok (even so there is less contact to the pulley’s), but as soon as you move it again, it will build up this gap when leaving the pulley. This happens in both directions and can even cause the belt collide with itself or the printers frame during the backlash. You can even hear when the belt is clapping together or hitting something. You also cannot avoid this with tightening.
I had these metal belts on my TronXY, when I got it second hand. Two pulleys between rods and you would expect perfect parallel belts with a round end on both sides, but that did not look like that at all. There always was a bulky side next to the pulleys.
On the GeitPrinter I tried metal belts at first, but you could hear the belt swing around and flopping its way back after turning. The only use case I see for metal belt is, where you fixate the belt flat onto a surface and roll over it, like some CNC types do, but they usually use bigger belts, too.
After replacing them with fiber glass enhanced gt2 belts, they look like they should. Now I am using them on all of my printers, while the metal enforced belts got dumped, even so they looked so cool in white.
Thanks for the info. Good to know about how the steel behaves. Any comments on the other issues, like whether I actually need to replace, how to check, etc.?
I had issues with my Anet A8 last year. When moving the print head along the X axis by hand, there was a point where it got stuck. It felt like if there was something inside a belt teeth or a teeth was missing completely. But there wasn’t. I assumed the idler or the X motor had the defect, so I removed the belt and this is what I found:
The belt visible in the image above is flat on the table and not mounted or fixated otherwise. This was the cause. When tightened on the printer, this little corner wasn’t visible. It just caused the feel of a speed bump, when moving the print head by hand and this section reached one of the idler teeth at the end of the X axis.
I have no clue how this happened. When I build the printer about three years before the belt was unharmed. It is a cheap plain rubber belt, but I have no idea how it changed to become permanently deformed in this way. Even when not using a printer for a decade I would expect the belt to be stretched along its length, along the X axis and not move sideways in any way.
Interesting. I haven’t removed any of my belts yet so I don’t know if any of mine have this “feature”. But, I do have the “bumps” as you call them, but only when I move the head somewhat quickly. Not really quickly, but if I move it quite slowly there are no bumps.
The only thing I can think of for your belt is to compare it to a 2 by 4. There’s an old, old saying in the lumber/woodworking industry: “a straight 2 by 4 is one that just hasn’t made up its mind yet”. I’m wondering if there might have been some unresolved stresses in the rubber, from when it was made in the factory. Over time, the stresses resolved & led to the distortion.
