I am ready for Multiple Hotend/Color Extruding! How?

Are there any good duel hotends on the market that help preserve print space, and any good tutorials on how to calibrate the hotends and set them up?

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kfootball15
Are there any good duel hotends on the market that help preserve print space, and any good tutorials on how to calibrate the hotends and set them up?

I should've said, I know of several duel hotends but are there any the community has used and would recommend?

You can take a look at Kraken from e3d if you're feeling adventurous.

There are plenty of hardware options but the software is far behind. I would recommend waiting until the software catches up.

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FFF Settings Calculator	Gcode post processors	Geometric Object Deposition Tool Blog
Tantillus.org	Mini Printable Lathe	How NOT to install a Pololu driver

I have a RRP tricolor mendel and I've pretty much given up with multicolor printing for now. I've had three hotends on my machine for nearly a year now...

* The leveling of the three nozzles is a pain. Slightly different hotend construction means different Z adjustments and the RRP method of attaching the hotends seems hokey. In general the nozzles end up angled inwards for me. I asked RRP how the hotends will attach on the multi-color Ormerod, but apparently that is top secret.

* If you have three nozzles and your print raises up or curls even slightly, one of the nozzles not in use (i.e. at a standby temperature or cold) can catch on the print. So your printing has to be perfect. Less room for error.

* The RRP Java-based slicer has things like a wipe tower, etc. but it is pitiful IMO. Slow, clunky and the controls are awkward. They seem to have abandoned it in favor of Slic3r, but I have never manged to get Slic3r to work properly with priming all hot ends. I suppose they have to be manually primed. Here is where I reported that problem over a year ago: https://github.com/alexrj/Slic3r/issues/1021 and again two months ago (along with other multi-color issues): https://github.com/alexrj/Slic3r/issues/1604. Basic multi-color functionality seems to be a low-priority for the slicer developers. Maybe it is complex to implement?

* I've looked at several slicers and ran into problems with them all. If I could find a commercial slicer that ran on Windows and properly supported three hotends in a user-friendly way (priming, wipe tower, AMF, tested) I would gladly put some money down for a license...

* Once in a while the settings stored in my RRP mendel are scrambled and have to be reset. This includes the offsets, PID and standby temps for the second and third nozzles. This is tedious. I went through debugging this with RRP months ago but when it magically fixed itself there was no further debugging to try. The problem is that you don't know when you turn the machine on that the settings are scrambled - so they have to be checked before every multi-color print. Again, tedious.

* Creating suitable STL or AMF files is currently not easy IMO, especially when working with other people's mono STLs that you want to combine (i.e. Luke Skywalker lego man). I've even developed a free utility to get AMF files out of Geomagic Design to help with this in the hope that it would make it a bit easier for others.

I'm sure someone will respond saying it is all working fine for them. If so please post your detailed slicer setup so I can give it a try including startup g-code and toolchange g-code and how you are generating STLs/AMFs.

Andy

Edited 14 time(s). Last edit at 02/14/2014 11:32AM by ajayre.

Hi ajayre, Great detail post, thanks...

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ajayre
* I've looked at several slicers and ran into problems with them all. If I could find a commercial slicer that ran on Windows and properly supported three hotends in a user-friendly way (priming, wipe tower, AMF, tested) I would gladly put some money down for a license...

Have you thought of offering a bounty? ( Reprap Bounties ) That way the whole community continues to benefit...

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ajayre
* Creating suitable STL or AMF files is currently not easy IMO, especially when working with other people's mono STLs that you want to combine (i.e. Luke Skywalker lego man). I've even developed a free utility to get AMF files out of Geomagic Design to help with this in the hope that it would make it a bit easier for others.

Sounds interesting, I'm not ready to use something like this, but where have you published this, etc... (links in your signature would be good, that will spread the word).

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[blogger.kritzinger.net]

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CraigRK
Have you thought of offering a bounty? ( Reprap Bounties ) That way the whole community continues to benefit...

You would have thought that the companies selling repraps with multiple heads would have money to invest in slicer development to make sure their products are well supported... And yes, I have tried Cura but also had problems.

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CraigRK
Sounds interesting, I'm not ready to use something like this, but where have you published this, etc... (links in your signature would be good, that will spread the word).

I'm active in the Geomagic Design forum where I make it known. It isn't useful to 99% of people on here as Geomagic Design isn't that popular, however you can find it here: WizoPrint

Andy

Edited 2 time(s). Last edit at 02/14/2014 11:34AM by ajayre.

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ajayre
You would have thought that the companies selling repraps with multiple heads would have money to invest in slicer development to make sure their products are well supported...

True!!!

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[blogger.kritzinger.net]

This is unfortunate. I'm not engineer, but I would love to figure out a way for the nozzles to autolevel. I can experiment with this in my free time if anyone has any ideas. I have autolevel beds on all my printers and they solved almost every issue I was having up to that point.

This might sound absurd, but as a starter idea, perhaps having each extruder/hotend on its OWN X and Z axis, with its own auto leveling endstop attached. This way you can calibrate each extruder and have them autolevel after every few prints, and avoid having to calibrate each hotend all the time

Now obviously that's not the cheapest thing in the world (Longer threaded rods for the structure, 2 more smooth rods and threaded rods per extruder, more servos and endstops, much large print area to accomodate the extra X carriage, 3 more stepper motors etc... and is pretty impractical.

But that concept is a start!

It would be cool if we as a community could come up with a dependable solution. You guys can throw ideas at me and I can do my best to test them out. Right now our only real solution is to purchase a 2500$ cubex printer, which is really a stupid purchase when you consider how fast this tech is moving and how printing in just 4 colors is going to be a standard for printers in a year or two.

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kfootball15
Right now our only real solution is to purchase a 2500$ cubex printer, which is really a stupid purchase when you consider how fast this tech is moving and how printing in just 4 colors is going to be a standard for printers in a year or two.

When the Kisslicer forum was still up it was full of Cube users because Kisslicer is the only slicer available that worked with its old outdated gcode commands. From their comments the Cube was useful as a paperweight and not much else unless you used Kisslicer because the software it came with was complete crap. But even with Kisslicer you had to have old firmware installed on the machine to be able to circumvent the cartridge so buying one now with the updated firmware would be like buying a large expensive paperweight. This is even worse because Kisslicer is no longer being developed.

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FFF Settings Calculator	Gcode post processors	Geometric Object Deposition Tool Blog
Tantillus.org	Mini Printable Lathe	How NOT to install a Pololu driver

Yeah I bought a cubify sense3D scanner and their software was completely awful, so I am not surpised!

I have a RepRap Tricolour Mendel printer as well and went a Different rout. One hot end, easy to adjust, multiple extruder drives. Tack a look at this: [reprappro.com]. I use the Ormerod Duet Controller with the Extender board: [blog.think3dprint3d.com]. Works very well with the DC42 FW and Cura [wiki.ultimaker.com].

Very interesting. Some questions:

- what does your toolchange g-code look like? I want to understand how you solved the problem in Dr Bowyer's post about strings of filament left trailing behind on a retract

- what settings are you using in Cura? For example how are you purging any left-over filament? Infill first on each layer?

- do you have any pictures of sample prints?

- did you use Dr Bowyer's implementation or did you make some tweaks? If you made tweaks can you share them?

- why did you switch from using the two Melzi's you already had to the Duet with extender board?

- what length is your bowden tube from hotend to the merging block?

Thanks! Andy

Edited 2 time(s). Last edit at 10/12/2014 09:21AM by ajayre.

I like this idea. 3 extruders but one hot end.

[forums.reprap.org]

[www.deltaprinter.co.za]

I plan on building a version of it for my OrdBot.

No problems with levelling
All metal construction
No fan cooling
one heater element
one thermistor
less wires

Only disadvantage I can see is water cooling, but using 1.75mm filament and small bore water tubes, free movement of the assembly should be maintained.

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gdwinslow wrote:
have a RepRap Tricolour Mendel printer as well and went a Different rout. One hot end, easy to adjust, multiple extruder drives. Tack a look at this: [reprappro.com].

Very interesting. Is there an .stl file available or better still a .scad file?

It would take an age to redraw it.

Kraken for sure.

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pushthatbolder
Kraken for sure.

IMO a single hotend solution is far more elegant, as well as being cheaper, easier, lighter, etc.

Andy

With the multiple filaments in one extruder set up, wouldn't you have issues with the filament either sticking (PLA) or stringing out and clogging (PLA if warmer, ABS)??

I've been looking at what is required to switch to multiple extruders. I've been shopping for bits and checking out Thingiverse, here and software. Software is still the number one issue.

The parts are the easy part. There's the e3d Kraken which is really nice if expensive, but I've seen nothing as elegant for three or four extruders. I've not wired it up to anything yet, software means I can't see much point right now.

Your electronics may need upgrading too. If you have RAMPS you can do two. RAMBO gives you three, and DUET+DUEX gives you six. I'm using my original RAMPS because I plan to get two extruders running on my current machine first. There are other hardware options, I'm just not as familiar with them.

RepRapPro have their tri-color mendel. I think this is a really well layed out machine, so it might be worth looking at their instructions. They specifically have you build it as a single extruder machine and then convert it to triple.

Software is all looking a bit poor tbh. I fully understand why, it's a complicated problem and you're not going to code it if you don't need it, so...

Actually, in the System files on the duet i back the filament off slow then fast till it is back before the many to one filament jig. This creates small diameter strings. In my many to one filament jig the tracks or channels are almost square. the strings end up in the corners. in 2 months of operating, i have had one clog do to and exparament i was trying in the gcode. was actually thinking of making a my many to one filament jig so it snapped together, but its never clogged other then that one time. Software is a problem no-mater what setup you have. I have seen industrial printers in operation and all the software needs work. I am not a fan of Makerbot, as i don't like there software. But there multiply ext-ruder slicir dos do the Wip and prime tower right. Cura, Slice3r and Simplify 3d are coming along, but still primitive in my opinyone. it could be i am critical of them as i am a software engineer. Any ways, hop this helps

gdwinslow - did you see my questions to you above? In particular posting your toolchange gcode and firmware changes would be very helpful to everyone else to try it out. Thanks.

Andy

Edited 1 time(s). Last edit at 10/15/2014 04:37AM by ajayre.

Ok, hear is my Printer sys Files. Not however you will need to adjust them for your setup, or you may have crashes.

To do a Layer change (test). I used this code witch I manually inserted:

;
; Change Tool
;
M117 Changing Color
M83
G0 F3600 X198 Y200 Z{NEXT_LAYER_HEIGHT}
T3
G1 Z0.4 F200 ; Put nozzle down for Cleaning
G1 X198 Y15 E20 F900
G0 Z{NEXT_LAYER_HEIGHT}
M82
G92 E{LAST_E_POSITION}
;

Note, you will need to insert the numbers from your print in the {NEXT_LAYER_HEIGHT} and {LAST_E_POSITION} variables.

Sorry, hear is the Cura INI. but like I sead it dos not work well. just like all the rest of the programs that are supposed to do multicolor

oww, about 60mm on Bowden tub from hot end to Switch block

About the question:

why did you switch from using the two Melzi's you already had to the Duet with extender board

I burnet the Hot bed controller of it long time back. Went through several other controller boards. Smocked the hot bed Controller of one and the connecter for the other. I am and embedded engineer so I was waiting for some one to get smart and use a Chip with enough horse power to handle HTTP and FTP protocols, as well as be a Machine controller. I infect looked at the Atmel chip used and the development environment for it to do exactly what the Guys did with the Duet and the extender board. My work unfortunately absorbs most of my time, and I am getting to old to do this 3 in the morning work ours back at another job at 6.00 am and survive any more.

Hop this helps