Steel reinforced belts, why not?

Hi! I just received all the parts and today i’ll go looking for the conduit (25x2, i’m aiming for a large CNC).

The fact is that the belt i bought are steel reinforced, i thought they might be better, less flexible, these are the same i mounted on the 3d printer.

Unfortunatly i noticed too late that you suggest to buy NO-reinforced belts.

Why so?
The lose in flexibility might put too much tension on the printed parts?
Am I missleaded by the reinforcement? Since I think that these might be more strong, maybe less durable but stronger, allowing more precision, lot’s of CNC works with leading screws that sure have zero flexibility.

I checked with a research online looking for this question and I wasn’t able to find an answer, probably i poorly searched for it, I probably asked something that already has an answer on this forum… Hope not.

I believe the reinforcement can (has) fail leaving you with a tiny section of really stretchy belt.

For applications like the mpcnc, the way the belt is routed (v shaped) can cause the steel reinforcement to break. Take a metal wire or even a metal coat hanger. Bend a section back and forth repeatedly and see what happens. It will break.


Steel reinforced belt works great for applications like a non serpentine belt, so like a car where the alternator, ac, water pump run on separate belts, the belt stays circular.

Yep, bending radius is too tight. Work hardens the wires, then they break.

I really didn’t thought about that, 'cause in the 3d printer for example the belt still bend, but only in one direction, so it’s never a back and forth bending… Yeah, like this it will last very little.

But still I can’t just use any rubber belt, looking on the suggested parts I can see only information on size and step of the belt, what material should i look for?

I think the belts in question are still reinforced, but they’re reinforced with fiberglass filaments running through them. You can see them when you cut the belts.

The parts spec say don’t get the steel reinforced belt, they don’t say to get non reinforced belt. All belts are have something running along the axis, so there isn’t really “no reinforced” belt. In this case, if it’s not steel, then it’s fiberglass.

I thought that for lite applications non-reinforced belt were an option.
Then i thought that the options were non-reinforced or steel reinforced XD

Ok, perfect, i’ll use this i bought for other application and i’ll buy the one with fiberglass, i still need to print all of the parts.