Any good light weight direct extruder/hot-end?

peirof

@zapta said in Any good light weight direct extruder/hot-end?:

HEVO
HI...

interesant solutions are... Nimble extruder or Flex3drive....

zapta

@peirof said in Any good light weight direct extruder/hot-end?:

interesant solutions are... Nimble extruder or Flex3drive....

I remembered somebody mentioned an interesting combination of a nimble or sidewinder extruder, which has a 33:1 gearing ratio, and a 50g nema 8 stepper https://www.omc-stepperonline.com/nema-8-stepper-motor/nema-8-bipolar-18deg-16ncm-23ozin-02a-48v-20x20x28mm-4-wires-8hs11-0204s.html .

Phaedrux

Titan Aero ain't bad. I use one on my DBot which is similar to the HEVO. With pancake stepper it's quite light. And you can gain some vertical travel depending on how you mount it since the heatsink is integrated inline with the stepper.

I think it's still lighter weight combo than any other V6 + extruder.

Remote direct drive eliminates the bowden tube lag, but it introduces it's own considerations. I wouldn't classify it as being truly direct drive in the classical sense.

garyd9

@phaedrux said in Any good light weight direct extruder/hot-end?:

I think it's still lighter weight combo than any other V6 + extruder.

I thought I saw something where the titan aero assembly (everything but the stepper) was weighed 5 grams heavier than the titan extruder + V6 assembly (everything but the stepper.) It was one the dozens of "titan aero" reviews (and while I have both assemblies myself, I've never bothered to actually weigh them.)

One advantage of the extruder+V6 is that it's easier to mount something like a piezo in the assembly between the V6 and extruder for very accurate "in nozzle" leveling/calibration.

whosrdaddy

@zapta you mean this?

fcwilt

Hi,

I've tried several setups over the years.

My current choice is a Zesty Nimble. Small, lightweight, easy to mount and very easy to change filaments.

Frederick

fcwilt

I perhaps should have mentioned that I had Titan Areo setups at one point and found changing filament was frustrating. Sometimes it was easy, other times anything but.

I would never suggest to anyone to go with them.

I also tried the Flex3drive but much prefer the Nimble.

Frederick

zapta

@whosrdaddy said in Any good light weight direct extruder/hot-end?:

@zapta you mean this?

Yes, this one, but I can't find anymore the 40g nema 8 stepper (lightest I am finding now is 50g). I am pretey sure I saw in past, (at stepperonline ?) any idea where to look?

Also, I consider the sidewinder version of the zesty to have the motor at a lower position.

Edit: found the 40g nema 8, https://www.moonsindustries.com/p/nema-8-standard-hybrid-stepper-motors/ms08hy1f4050-000004611110028968 . Need to find how to couple it's shaft to the Nimble.

zapta

@fcwilt said in Any good light weight direct extruder/hot-end?:

I also tried the Flex3drive but much prefer the Nimble.

How does the nimble handle TPU? With bowden I have good experience with the bondtech dual drive approach which grips and drives the filament from both wheels.

Alexander Mundy

I print 40 hardness TPEE no problem with the Nimble. The aforementioned Nema8 was a conversion by another which does away with the cable and places the stepper directly above the Nimble with adapters he designed. The stepper is this one.

https://www.moonsindustries.com/p/nema-8-standard-hybrid-stepper-motors/ms08hy1f4050-000004611110028968

As to my personal preference I use the cable system as comes with the Nimble with escap (now Portescap) P430–258-005-01 disc magnet stepper motors with windings in parallel on my deltas. I think there are only a couple of us using these.

With them I run maximum instantaneous speed changes (jerk) of 600 mm/min instead of the recommended 40 mm/min for standard steppers. Acceleration of 1500 mm/s^2 instead of the recommended 120 mm/s^2 for standard steppers. This keeps retract settings “normal” or above “normal” if wanted, and pressure advance does not interact with the lower settings to cause bogging down print speed.

Pros:

Rotor inertia is a very low 3 g-cm2, 200,000 rad/s^2 acceleration so it can stop and reverse quick for retract and return.
100 steps/rotation (3.6 degree) so 1/2 the required steps/mm to keep from a large number of needed steps with a 30:1 reduction which shortens driver pulse width and the corresponding rise and decay don’t get too short.
2.5 ohms resistance and 3.5 mH inductance per phase with 2.3 V/kstep/s back EMF so quick ramping up and down of step pulses.

Cons:

10 to 12 oz/in of holding torque & 0.93 oz/in detent torque which is lower than even the recommended NEMA 14 pancake but I haven’t had any problems with the lower torque even driving a volcano close to max volumetric.
I do actively cool them with a small fan because they get warmer than I like without, but don’t think it would be absolutely necessary.
They are extremely expensive unless you can find them used.

https://www.portescap.com/sites/default/files/p430_specifications.pdf

samlogan87

I run a G3 flex3drive which I love. Changing filament was a little annoying at the beginning until the guide clearanced itself a bit and now it is easy. It’s really well made and solid which I liked. They have just released G5 and it looks to be a tidy bit of kit. I would look at them as well.

Regards
Sam

zapta

Thanks @alexander-mundy, that's really good information.

Does the nimble's flex cable wears out over time? IIRC I read posts here to this effect.
Do you know how the shaft of the nema 8 is attached to the nimble? It has a 3.5mm D shaft https://www.moons.com.cn/medias/MS08HY1F4050.pdf?context=bWFzdGVyfHJvb3R8OTM3MTMzMXxhcHBsaWNhdGlvbi9wZGZ8aDBhL2hiNC84ODI1NjI4NTI0NTc0LnBkZnwzMTUwZTA1ZjAwZjI2MDY5ZjFjOGQyYjhiMTc4ZWY0MWIzYTAwN2I5ZTU2MGJhMmU1YmM0YmYzZmFmODY4NDk0&attachment=true
Any reason not going with the direct nema 8 appraoch?
I am thinking getting the sidewinder nimble to have the nema8 mounted lower. Is this reasonable?

Alexander Mundy

@zapta

He designed an adapter and had it shapeways printed that accepts the small D shaft and has a square end that goes in the worm gear where the cable normally goes.

My cables are original black sheath version (well they sent us original buyers replacements shortly thereafter because of a production defect) and they have been using a newer version for some time now but I don't have the red sheath version. I have had no problems, but I'm a hobbiest printer. However I have followed the Nimble since the beginning and have not heard of cables wearing out, only a few production issues here and there.

Can't speak to the Nema 8 since I've not tried it.

fcwilt

@zapta said in Any good light weight direct extruder/hot-end?:

Thanks @alexander-mundy, that's really good information.

Any reason not going with the direct nema 8 appraoch?

I am thinking getting the sidewinder nimble to have the nema8 mounted lower. Is this reasonable?

Hi,

When you say "direct nema 8 approach" do you mean not using the normal Nimble cable?

If so, that would seem to defeat the purpose of using the Nimble in the first place, which is to get the stepper motor mounted to the frame instead of some part of the moving gantry.

Frederick

gtj0

@fcwilt said in Any good light weight direct extruder/hot-end?:

If so, that would seem to defeat the purpose of using the Nimble in the first place, which is to get the stepper motor mounted to the frame instead of some part of the moving gantry.

Frederick

It depends... With the Nimble (which I also use), you get the high ratio gearing which allows you to use a smaller stepper like the NEMA 8s. Balance that against the mass of the drive shaft, which you still have to move, and it may be a better arrangement for some.

zapta

@gtj0 said in Any good light weight direct extruder/hot-end?:

Balance that against the mass of the drive shaft, which you still have to move, and it may be a better arrangement for some.

IIRC, several people mentioned in posts here that the flex cable tends to wear out. Is it so?

gtj0

@zapta said in Any good light weight direct extruder/hot-end?:

@gtj0 said in Any good light weight direct extruder/hot-end?:

Balance that against the mass of the drive shaft, which you still have to move, and it may be a better arrangement for some.

IIRC, several people mentioned in posts here that the flex cable tends to wear out. Is it so?

I've had it for almost a year now and had no issues.

Alexander Mundy

@zapta said in Any good light weight direct extruder/hot-end?:

@gtj0 said in Any good light weight direct extruder/hot-end?:

Balance that against the mass of the drive shaft, which you still have to move, and it may be a better arrangement for some.

IIRC, several people mentioned in posts here that the flex cable tends to wear out. Is it so?

I've had 2 for over 2 years and they are just fine. As I posted before, I am a hobbiest so probably just 30 kg or so of filament used.

martink1974

i got a flex3drive to reduce weight on my delta and could not be happier , seems for most part a solid and functional design , changing out filement is a doddle and just getting it dialed in at moment first few prints are looking good and easy to get up and running

got retractions dieal in after a few prints and its harder to see but

the 4th benchy came out mint

huge improvement over my previous bowden v6 and bulldog extruder setup

fma

With such ratio, I think a DC motor (+encoder) would be much better than a tiny stepper motor (either using the cable or in direct-drive config)...