Toward the Graal : Ultra-light extrusion

Toward the Graal : Ultra-light extrusion Hi, everybody! All printers have an interest in light extrusion heads, especially deltas. And we all know that pushing the filament as close as possible to the fusion zone, i.e. Direct Drive, is better. And if the extruder could be a Bondtech, with two symmetrical hobbed gears, that would be perfect! And also with a water-cooled Hot-End, but simple, not a gas plant... [attachment 105515 DR_runis.JPG] Would you like to have all this in a 32g set? Yes, 32g, not 320g! More explanations on my recently added page on the HackaDay website: [hackaday.io] This is part of my project for the delta robot Zatsit, quoted here, but on another subforum (This might interest you too!) [reprap.org] https://reprap.org/forum/read.php?1,825347,825347#msg-825347 Sat, 07 Mar 2026 01:41:30 -0500 Phorum 5.2.23 https://reprap.org/forum/read.php?1,825347,854075#msg-854075 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,854075#msg-854075

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M_Xeno

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Any news on bringing this promising extruder to market?

I'm working on it, but most of my time goes to completing the deliveries of the delta Zatsit printer for my Kickstarter Backers.

It would be a great idea to post an update to KickStarter.]]> frankvdh General Sun, 26 May 2019 23:19:59 -0400 https://reprap.org/forum/read.php?1,825347,854072#msg-854072 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,854072#msg-854072 tray General Sun, 26 May 2019 20:37:35 -0400 https://reprap.org/forum/read.php?1,825347,854060#msg-854060 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,854060#msg-854060

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Any news on bringing this promising extruder to market?

I'm working on it, but most of my time goes to completing the deliveries of the delta Zatsit printer for my Kickstarter Backers.

The first prototype I showed in this post evolved into a multi-material extruder concept (2, 4, 6...), with a single stepper motor, and a single electronic driver, for the 2xn channels. The basic idea is the same: a worm screw drives two pinch wheels simultaneously. In the multi-material version, the common drive shaft is horizontal, and the pinch wheel pairs come into contact with the drive by a simple pendulum movement. The switch from one material to another is therefore very fast.

The whole is miniaturized, and remains very light. The 2-way version weighs less than 40g (2 hot-end, water-cooled, 2 pinch wheels per track, common flexible drive shaft, support structure).

I hope to come up with a proposal that can be used on all types of 3D printers, and that will offer multi-material functionality, direct drive, lightweight and fast. It's very exciting. Stay tuned....]]> M_Xeno General Sun, 26 May 2019 14:20:36 -0400 https://reprap.org/forum/read.php?1,825347,853608#msg-853608 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,853608#msg-853608 www.ebay.co.uk]]]> MechaBits General Sun, 19 May 2019 21:30:04 -0400 https://reprap.org/forum/read.php?1,825347,853153#msg-853153 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,853153#msg-853153 www.mhz-powerboats.com]

It's 2.2mm instead of 3 something. Should be a little less weight & a bit more flexible.]]> warbunniex General Tue, 14 May 2019 10:23:20 -0400 https://reprap.org/forum/read.php?1,825347,852623#msg-852623 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,852623#msg-852623 tray General Mon, 06 May 2019 21:14:59 -0400 https://reprap.org/forum/read.php?1,825347,825936#msg-825936 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825936#msg-825936 There will soon be a Kickstarter campaign for the Zatsit kit (see www.zatsit.fr), but I don't think I would have time to integrate this extruder, which still requires optimization studies, and especially, for mass production. The association of a POM pinion, and a metal hobbed gear, must be simplified, it is much too complicated to produce in series.

But it will be done, because I think there is a market for such an ultra-light extruder.]]> M_Xeno General Sun, 17 Jun 2018 05:40:33 -0400 https://reprap.org/forum/read.php?1,825347,825916#msg-825916 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825916#msg-825916 obelisk79 General Sat, 16 Jun 2018 21:24:41 -0400 https://reprap.org/forum/read.php?1,825347,825612#msg-825612 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825612#msg-825612 M_Xeno General Thu, 14 Jun 2018 06:24:19 -0400 https://reprap.org/forum/read.php?1,825347,825607#msg-825607 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825607#msg-825607 Trakyan General Thu, 14 Jun 2018 04:42:59 -0400 https://reprap.org/forum/read.php?1,825347,825591#msg-825591 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825591#msg-825591 I don't quite understand what hassle you' re talking about.
I still have air-cooled Hot Ends, which I used at the beginning of the Zatsit project, before I developed the solution with water. I can replace them in a few seconds, if I feel like it, and this will not change any of the printer's other functions (cooling parts, extrusion, etc...). The design of Zatsit is such that all effectors are interchangeable, and are just attached with three screws.
The only hassle will be that it will be necessary to purge the water circuit, by blowing inside, before disconnecting it, just as when one wants to pass from a use as a 3D printer, to a use as a generic robot.
I'm guessing you haven't seen the videos where all this is explained. On the whole, it's very simple...]]> M_Xeno General Thu, 14 Jun 2018 02:46:57 -0400 https://reprap.org/forum/read.php?1,825347,825576#msg-825576 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825576#msg-825576 Trakyan General Wed, 13 Jun 2018 20:09:28 -0400 https://reprap.org/forum/read.php?1,825347,825523#msg-825523 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825523#msg-825523 Replacing this compact and lightweight water-cooled Hot-End with a classic and bulky 60g air-cooled solution would be a really weird idea! ;-)

The hot-End presented here really only has advantages, and remains compatible with all the standard stuff (nozzles, cartridges, etc...)

But if you really want that, it must be possible. You will need to make the adapter. The extrusion mechanism alone weighs 12g...

If you wanted to talk about cooling printed objects, Zatsit offers an excellent solution, very powerful, and here too ultra-light.

Give a look to these links
www.zatsit.fr
[hackaday.io]

You will have detailed responses to your questions, about durability, Hot-End exchange, etc.]]> M_Xeno General Wed, 13 Jun 2018 10:10:52 -0400 https://reprap.org/forum/read.php?1,825347,825520#msg-825520 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825520#msg-825520 warbunniex General Wed, 13 Jun 2018 09:44:38 -0400 https://reprap.org/forum/read.php?1,825347,825519#msg-825519 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825519#msg-825519 You're right, and that's a good question : available flexible shaft have a quite high linear mass.

For my prototype, I used only the core of the flexible shaft, and I replaced the sheath by another lighter one, of my manufacture.

But above all, I installed the stepper motor on a gimballed support, in a flystruder position (suspended between the three carriages), so that the length of the flexible shaft is only 12 cm. Under these conditions, the inertia, and parasitic forces, due to the flexible shaft are without appreciable consequence.

However, as when I use a flystruder with a bowden tube, I have to reduce the maximum speed along the Z axis to 500mm/s instead of the usual 600mm/s, because of the mass of the stepper. X and Y are still 600mm/s, so, no consequence either.]]> M_Xeno General Wed, 13 Jun 2018 09:35:50 -0400 https://reprap.org/forum/read.php?1,825347,825514#msg-825514 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825514#msg-825514 Wrong : Flex3drive, Zesty Nimble and my setup use about the same ratio, for the same reasons (advance of the filament = worm pitch), and we all use a ~3mm flexible shaft, the smallest currently available.

I did try to use a second stage of gears, to be able to run a smaller motor, but then the problem is with pressure advance : the speed variations asked to the motor are way too high, and step losses occur, even without any back-pressure.

The gear ratio of the setup shown here is already quite high (1,5mm/turn is 4800 steps/mm with a 1.8° stepper, and x16 microstepping). Problems already occurs with not well suited steppers, i.e. too high impedance and inertia.]]> M_Xeno General Wed, 13 Jun 2018 09:08:31 -0400 https://reprap.org/forum/read.php?1,825347,825507#msg-825507 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825507#msg-825507 Origamib General Wed, 13 Jun 2018 08:26:30 -0400 https://reprap.org/forum/read.php?1,825347,825445#msg-825445 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825445#msg-825445

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M_Xeno
@o_lampe
The drive gears are big, as to limit stress and deformation of the filament. This has no effect on the e-steps/mm value: with a worm drive, hobbed gears advance by one pitch of the worm each turn, regardless of their diameter. Here, about 1,5mm/ revolution, a quite good resolution.

The reason, why other worm driven extruders use a big gear ratio is: they can pick a thinner/lighter and more flexible flex-shaft.
In your case this isn't true and the stiffness of the cable has a bigger negative influence. Why not add a second gear stage and advance to a better suited drive cable?
Direct drive with a small pancake stepper would then work, too.]]> o_lampe General Wed, 13 Jun 2018 02:25:24 -0400 https://reprap.org/forum/read.php?1,825347,825441#msg-825441 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825441#msg-825441
Also, great job on your delta, neat concept and execution. How well do the flexure hinges hold up over time?]]> Trakyan General Wed, 13 Jun 2018 01:16:30 -0400 https://reprap.org/forum/read.php?1,825347,825373#msg-825373 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825373#msg-825373 The drive gears are big, as to limit stress and deformation of the filament. This has no effect on the e-steps/mm value: with a worm drive, hobbed gears advance by one pitch of the worm each turn, regardless of their diameter. Here, about 1,5mm/ revolution, a quite good resolution.]]> M_Xeno General Tue, 12 Jun 2018 13:05:29 -0400 https://reprap.org/forum/read.php?1,825347,825369#msg-825369 Re: Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825369#msg-825369 The drive gears look huge, what's the e-steps/mm you can achive with that worm gear?]]> o_lampe General Tue, 12 Jun 2018 12:45:34 -0400 https://reprap.org/forum/read.php?1,825347,825347#msg-825347 Toward the Graal : Ultra-light extrusion https://reprap.org/forum/read.php?1,825347,825347#msg-825347
All printers have an interest in light extrusion heads, especially deltas.
And we all know that pushing the filament as close as possible to the fusion zone, i.e. Direct Drive, is better.
And if the extruder could be a Bondtech, with two symmetrical hobbed gears, that would be perfect!
And also with a water-cooled Hot-End, but simple, not a gas plant...
[attachment 105515 DR_runis.JPG]

Would you like to have all this in a 32g set? Yes, 32g, not 320g!

More explanations on my recently added page on the HackaDay website:
[hackaday.io]

This is part of my project for the delta robot Zatsit, quoted here, but on another subforum (This might interest you too!)
[reprap.org]]]> M_Xeno General Tue, 12 Jun 2018 10:41:40 -0400