I'm thinking of upgrading my printer's belts and looking at either synchromesh cable or

I’m thinking of upgrading my printer’s belts and looking at either synchromesh cable or GT2 belts. I’ve found a lot of discussion either way, but most of it consists of “I think…” or “I’ve heard…” or “Someone else has said…” all of which seems pretty low value.

The only firm difference I’ve found is that GT2 is “inherently anti-backlash” while synchromesh is not.

I guess what I’m looking for from this group is some input on the relative pros and cons of the two systems and why I should choose one over the other. I’m especially interested in personal experience with both options.

So… Any thoughts?

And one other question for those experienced with synchromesh cable: is it possible to form it into a continuous loop, all parts of which can pass through a toothed pulley?

My printer’s design requires a fairly small (about six inch around maybe?) continuous loop, so if I were to go with synchromesh I’d have to either make that loop myself since no one sells it that way that I can find or redesign the Y drive system of my printer to not need the loop.

I have a lot of experience with both GT2 and Synchromesh. Both are great, and both are anti-backlash. Synchromesh is quieter (you probably don’t think your belts are making noise, but they are), but cannot be made into continuous loops.

Ah, thanks, that helps make the decision both easier and harder. I really like everything I’ve seen about the synchromesh, and I’d really like to use it, but the Y-drive redesign is somewhat daunting at the moment.

I’m also 6000 miles away from my printer at the moment, so serious investigation of a redesign will have to wait a week or so.

At least I know I can always fall back on an anti-backlash belt if need be.

Got to love this community :slight_smile:

Just to clarify, you can crimp the two ends of a length of synchromesh cable together to make a loop, but the crimp won’t be able to pass through pulleys and mesh with the teeth of gears, so the loop won’t be able to make a full rotation.

That lines up with what I was thinking, unfortunately. It can’t be a drop in solution for me then.

One of the reasons I designed the Rroofl to run without continuous belt. Nice trick with only 1 Z motor :slight_smile:

I use GT2, it’s all I’ve ever used, I like it. Syncomesh is neat because it can go around corners in any direction.

Pretty much same excuse here. Used to use helicopter belt because T5 was ridiculous in NZ. Using T5 because it’s the smallest thing I could print a reliable gear for!

All of my machines can print reliable gears for GT2, T2.5, and MXL…

Yeah, but I have to design machines for klutzes like me :slight_smile:

@Whosa_whatsis that’s on a what…0.35 nozzle? Have you gone down to the small 0.2 nozzles or anything?

Actually, the ones I made were on a .4mm nozzle, but obviously it should be even easier for a .35.

Hmm. I haven’t actually tried toothing that small on my machine. It’s been so long since I tried printing actual gears… What slicer are you using? Any special considerations to take? PLA? ABS? Are the files you’re using compensated in any way?

I did a little tweaking in the STL to compensate for the way the tooth profile deforms when it wraps around the pulley. I used ABS, and I think I used slic3r, but I’m not certain, and it could have been skeinforge. The STL is on the thingiverse page for Wallace (http://www.thingiverse.com/thing:14208). It’s labeled as an MXL pulley, but I ended up using it for GT2.

The Wallace parts out cheaply enough that it could be an impulse project. I think it might have to go on the “when I get a little free time” list. This hobby is quickly becoming addicting.

There’s a redux version of Rroofl about to surface, made from MDF or plywood slab done without convenient CNC machines. 1 Z motor, no continuous belt :slight_smile:

My input on the original topic:
I’m using HTD 3M belts on my machine with machined aluminum pulleys, with no signs of backlash at all. HTD is somewhat compatible to GT/GT2/GT3, can only take lighter loads (not a problem for us), is easier to source and quite a bit cheaper than the GT profiles.
That being said, i’ve never had a real issue with backlash on any of the machines i built with T5 belts and printed or machined pulleys.
I’d say unless you are really seeing lash issues, stick with the belts you have. If you do want to upgrade, try printing some tighter pulleys for the belts you have first.

For me, Slic3r is having a hard time with pulleys, it tried to add little one-wall-thick segments on to the outmost part of the profile, which made the pulley unusable without a good cleaning with a utility knife.

By the way, notation for HTD or GT belts is
- - M -
or for pulleys,
- - M -
One of my belts is HTD-1500-3M-15, so it has a tooth distance of 3mm, a width of 15mm and a lenght of 1500mm.
GT, GT2 and GT3 are several generations of the identical GT profile (and therefore fully compatible), each being rated for higher loads than the previous one. Each profile comes in 2M, 3M, 5M, 8M and so on.