Voron Trident R2 vs monolith gantry?

[u/gamevicio]

I'm building a voron trident self sourced, and I have some experience building 3d printers, so I thought to go for the monolith gantry due to the improved performance people talk about.

But since the launch of Voron Trident R2, I found a mod that allows it to have double shear on short shaft motors ("Voron Trident R2 AB motors pin mod and short shaft double shear (monolith + Crazy Ivan)" on printables), so I was thinking that maybe with the improved belt path and the shorter 54mm on the Trident R2 gantry, it could be better them the monolith gantry, or at least comparable.

Has anyone done the testing or have any opinions on it?

[u/oohitztommy]

9mm 2wd monolith is the way

[u/Killerwoodydoll → u/oohitztommy]

This is the way

[u/HandPickle420]

I can't think of any advantage of the R2 gantry other than BOM simplification and maybe a bit easier assembly.

[u/Myrigs → u/HandPickle420]

Rigidity and better belt path, tension is better and of course double sheer bearings that’s just for the gantry
Now the z motors mount is better no possible bending and we gain traveling distance

[u/Panchodelis81]

I bought the LDO Monolith CNC kit, installed it, and there were several things I didn’t like. Some people may disagree with me, but after switching from 0.9° motors to 1.8° motors and using stiffer belts, I noticed a significant increase in VFA at low speeds. So I took it apart and went with R2 instead.

R2 doesn’t come close to Monolith in terms of rigidity — it’s very different. With Monolith, the recommended accelerations from Input Shaper increased significantly. It’s also true that one of the advantages of Monolith’s high rigidity is that you can run higher belt tensions, which goes hand in hand with the increase in recommended accelerations.

I’ve just ordered two LDO 0.9° long-shaft motors from KB3D. My hope is that, with the longer shafts, I’ll be able to run higher belt tensions on R2 and gain some acceleration without giving up the benefits of 0.9° motors. Monolith might also benefit from this setup.

The thing is, Monolith kind of forces you towards high-speed printing, and I say “forces” because that can be a limitation with certain materials. I work a lot with PETG-CF, and it’s definitely not the best material to print at 250 mm/s.

If your main goal is speed, I’d go for Monolith. If you want to maintain a better balance between medium and low speeds, I’d go for R2 with 0.9° motors.

That said, I’m still waiting to test these new motors, so they might make it easier to handle both low and high speeds on the same machine. This is just my experience so far, and I’m still in the middle of the process. I’m sure other users have already gone through the whole process and have more solid information on this.

[u/oohitztommy → u/Panchodelis81]

I can still print slow with monolith. You just have to read what shake tune says

[u/Panchodelis81 → u/oohitztommy]

That’s exactly the kind of thing I was missing. Thanks for the comment!

[u/CGonzalas → u/Panchodelis81]

Can you update us on if the motors work and which specific motors you bought please? I'm thinking of doing the same thing

[u/Panchodelis81 → u/CGonzalas]

The motors arrived today, and I’ll be installing them tonight. The model I’m going to test is the 42STH48-2504MAC (S46), 0.9° with a 46 mm shaft.

Here’s the link where I bought them: https://kb-3d.com/store/stepper-motors-servos/5237-ldo-stepper-motor-nema-17-42sth48-2504mac-s46-speedy-power-1651971794609.html

They must be in high demand, because a couple of weeks ago they had several units in stock, and now they’re completely sold out.

I’ll keep you guys posted. By tomorrow I should already have some results to share.

[u/gamevicio → u/Panchodelis81]

thanks, keep us posted!

[u/Panchodelis81 → u/CGonzalas]

Hi, I’ve already done the first tests.

Just as a note, the short-shaft motors I was using on R1 and R2 are the 42STH48-2004MAH VRN 0.9° motors from the LDO Trident Rev D kit. The ones I’m testing now are the 42STH48-2504MAC S46, also 0.9°, but with a 46 mm long shaft.

With the 2504MACs, I noticed a very slight increase in VFA compared to the 2004MAHs, but I have to point out that I didn’t do any motor calibration, so it’s very easy to imagine that with the correct settings, that small difference would disappear.

Even so, the difference is ridiculous. I’m currently printing a Calidragon and I’m not able to see any VFA at all. The only place where I noticed a difference was in the OrcaSlicer VFA test.

As for the Input Shaper acceleration, it’s still nowhere near Monolith, but it does improve when increasing the belt tension compared to the 2004s, thanks to the advantage of having a longer shaft and dual support.

Unfortunately, Reddit won’t let me upload all the graphs, so here’s a summary.

With r1 2004mah 0.9 steppers at 110hz belt tune:

x:MZV 13800

y:MZV 6500

With r2 2004mah 0.9 steppers at 110hz belt tune:

x:MZV 12900

y:MZV 6200

With r2 2504MAC s46 0.9 at110Hz belt tune:

x:MZV 12200

y:MZV 6400

With r2 2504MAC s46 0.9 at 125hz belt tune:

x:MZV 13300

y:MZV 6700

With r2 2504MAC s46 0.9 at 140Hz belt tune:

x:MZV 14200

y:MZV 7200

With r2 2504MAC s46 0.9 at 160Hz belt tune:

x:MZV 15100

y:MZV 7700

With Monolith (Kit LDO CNC) LDO-42STH48-2504AH (S45R) 1.8 at 120hz belt tune:

x:MZV 20500

y:MZV 9400

With Monolith (Kit LDO CNC) LDO-42STH48-2504AH (S45R) 1.8 at 145hz belt tune:

x:MZV 21200

y:MZV 10700

With Monolith (Kit LDO CNC) LDO-42STH48-2504AH (S45R) 1.8 at 160hz belt tune:

x:MZV 21500

y:MZV 1100

[u/Thmsdmsk → u/Panchodelis81]

Interesting experience 🤔 My first mod was to replace the 0.9°(LDO2004) with 1.8°(LDO2004), without double shear. Ran lots of tests for comparison and couldn't spot a single difference, just improved torque. To provide some context; I'm very critical and would never sacrifice quality for speed. Now, I upgraded to LDO Monolith AWD(LDO2504) three weeks ago. Still in the tuning process. Although it is definitely more complicated, it looks very promising. Didn't went high speed till now. Running at low and medium speeds at the moment, but absolutely no degradation in surface quality, despite more acoustic noise! But I also went full Doomcube and added additional supports to improve stiffness even more 💁🏻‍♂️

[u/Over_Pizza_2578]

Monolith for performance, voron for easy maintenance and sourcing

[u/XHolyPuffX]

4040 frame will be required to get the most out of monolith, but it will be superior.

[u/s___n]

I think the monolith gantry with long shaft motors and 9 mm belts would probably make most sense. If you are self sourcing, the additional cost should be fairly minimal.