Did anyone make a iDex with dual x gantry bar?

[dc42]

@t3p3tony said in Did anyone make a iDex with dual x gantry bar?:

@deckingman Having them stacked avoids collisions, but having them at the same level is some mechanics I would like to see....

Avoiding collisions between the two gantries would be the same as avoiding collisions on an IDEX machine, only for the Y axis.

[T3P3Tony]

@dc42 Indeed, however having the two extruders independent could open up the possibility of both of them printing, at the same time, on different parts of the same model.... if they could avoid crashing into each other.. The slicer would need to generate "safe" gcode as well.

[Cata]

I see one on facebook, use duet

[mgrimes1907]

I have an X and a U on two different rails. Haven't put the extruder on the U yet but carriage is there and functional. I have been putting it off because I have to redesign my extruder brackets to allow room for the cooling fan between the carriages.

They are both riding on 40/20 extrusions seperately. I have Two Y motors, an X, motor, a U motor, four Z motors pushing 1000 mm Ball screws, and hopefully soon, two extruders. No empty drivers on Duet or Expansion Board. Heat sinks on all drivers witha 24 volt, 90 mm fan blowing across them.

[T3P3Tony]

@mgrimes1907 Sounds really interesting, I hope you will be able to put some pics/video on the forum?

Btw:

@mgrimes1907 said in Did anyone make a iDex with dual x gantry bar?:

Heat sinks on all drivers witha 24 volt, 90 mm fan blowing across them.

Most of the heat is dissipated from the Duet/Duex drivers through the PCB so the most effective cooling is though blowing the fan across the underside of the board. Very little heat makes it through the top of the driver packages.

[mgrimes1907]

@t3p3tony I know but I have had the "Driver 6, 7, 8. 9 Temperature" Warning several times but not since the heat sinks were installed. All Z motors are on 6, 7, 8, & 9. There are 2.8 amp NEMA 23 as well as the 2 Y Motors. Only X, U, and extruder motors are NEMA 17. They are 2.0 amps each. I have the amperage in the config.g set to 80 % of those ratings. Thinking about playing around with the Z motor amperage as they are growling a bit with mesh bed compensation.

[mgrimes1907]

@t3p3tony BTW , I am not quite sure how to post Pictures on this forum as this is the only forum I subscribe to.

[T3P3Tony]

@mgrimes1907 You can cut and paste them into the chat, or click on the " Picture" icon.

I think they need to be <2Mb

[mgrimes1907]

@t3p3tony !
I hope you can see this. This photo is from the top right corner of the printer looking down you can see the two extrusions with the drive motors on the other end. There is only one extruder on the left gantry rail but you can see the carriage on the right one. As I said before, it is functional. I need to re-engineer my extruder mounts to squeeze the fans in to pass each other.
Thats a print I did last night. It's 205 mm on the X axis, 23 mm on the Y axis, and 300 mm on the Z axis. Its only half the wing. I would print it in one print but it gets a little wobbly with such a small Y axis footprint. 10 1/2 Hrs. print time.

0_1528729507075_b280a8a0-54fd-4153-8f90-5a773f836a94-image.png

[mgrimes1907]

@t3p3tony
One picture didn't show up. Click on the link above the pic to see the overhead shot

[mgrimes1907]

@t3p3tony By the way, I was going for functionality not aesthetics. There are a load of wires to deal with and I really need to mount my Duet down to something, but it works day in and day out.

[mgrimes1907]

@mgrimes1907
The Left side is different from the right side. For weight purposes, they will both be the same as left on final build. Single wall extrusion at 60 mm/sec.
It's not a 3DLabPrint design!

[3D_low]

Here's a sketch of what i'm thinking about.
Extruder move on the X axis like they would normally but each "X-bars" has it's own Y motor making the thing an idex printer. The main advantage of this would be the weight reduction of the x-bars.

It would of course need a DueX5. One could also decide to put in a 3rd bar and use 1-Z, 3-X, 3-Y,3-E motors and take full advantage of the DueX5. It would however need strict rules to prevent crashes

[mgrimes1907]

@3d_low Just for curiosity sake, what are you trying to accomplish with two Y gantries? If its only a weight issue, then use bowden tubes and keep the weight of the extruder motor off the gantry. The only downfall to this is printing with flex. Not saying it's impossible to print flex with a bowden tube either. If you are printing with two extruders, you are either going to park one while the other is printing or you will be doing a ditto or mirror print which you will have to half the bed up anyway. The only reason I have designed mine that way, because I have 36 inches of X travel on the bed and I can mirror or ditto print and I still have 18 inches for each extruder and if I want to print a multi material, I am able to still reach the entire bed with each extruder.
Two Y axis drives would be too much sugar for a dime for me

[T3P3Tony]

@3d_low yeah, I see that but did not see a particular advantage over existing IDEX unless you wanted to be able to print on two parts of the same model at the same time, however that would require some clever slicing!

[mgrimes1907]

@t3p3tony I was not aware that you could do that. Having two different parts of a print going at the same time seems to be to much going on at one time for me. I might not be coordinated enough to keep all that straight. I have a hard enough time keeping my profiles in Simplify3D with the correct part of the print, I can't imagine having two profiles printing at the same time at different parts of the print.

[dc42]

You could put two IDEX carriages on each gantry to create a 4-material printer.

[3D_low]

@dc42

Yeah that could be done but I would need additional stepper drivers. Is it possible to use multiple duex boards?

To answer the other questions : this machine will be of big size (600x600) so dual print becomes available. I’m making a lot of molds for a foundry where I have to print 2 identical parts. An idex printer would allow me to cut the cost and lead time for my customer while raising my profit margin.

I’m using a dyzextruder since I plan on using a heated chamber. Those things are incredibly reliable and robust and will also allow me to print high end materials. I quickly estimated the weight of an additional dyzex + x-motor setup to roughly 650g. Shaving this off the axis would allow faster accélérations and considerably cut print times. Most parts i print for my customers are over 20 hours so a 10-15% reduction in print time is considerable. As for complexity, I don’t really see where the challenge is there. I would only need an additional set of linear blocks, another Y motor/belt and a set of pulleys.

[dc42]

@3d_low said in Did anyone make a iDex with dual x gantry bar?:

Yeah that could be done but I would need additional stepper drivers. Is it possible to use multiple duex boards?

No, but you can connect a DueX5 plus two additional stepper drivers to CONN_LCD, making 12 drivers in total. So 4 X motors, 2 Y motors, 4 extruders, and 1 or 2 Z motors.

[JoergS5]

To construct independent extruders, you could install them on different levels and:

• guide cables and filament to the side, not top
• extruder 1 y position always smaller than extruder 2 y position, or you lift/tilt the extruder while crossing
• for hotend being on same z level, you need to have one hotend more distance from x axis level than the other

This would allow more than 2 extruders and all steppers independent from each other.

If you want to have independent extruders, I would also consider an extruder exchanger like this one:
https://hackaday.com/2017/08/27/3d-printer-tool-changer-gives-you-access-to-lots-of-extruders/