Dual extrusion how-to

[Eaglezsoar]

Figured it out....The settings in the EEPROM were bad...lol so easy

Could you tell us what settings were bad, this would be a help to future users who are reading this thread and want to implement dual extruders.

[pyrophreek]

Turned out the eeprom settings for the second extruder were blank. Just copied the ones from the first to fix. Will properly calibrate each individually later.

[Eaglezsoar]

Turned out the eeprom settings for the second extruder were blank. Just copied the ones from the first to fix. Will properly calibrate each individually later.

Thank you for letting us know this, it will help everyone when their turn comes.

[dpmacri]

I forgot that I had to do that, too -- thanks for the reminder!

[Bill Havins]

Hello to all.

I have been watching this thread with great interest. I hope to use dual extruders with the second extruder dedicated for printing HIPS support material.

How has progress gone with the setups and configurations described above?

Would it be helpful if I developed my own ideas and added my experiences to this mix, or would I be "re-inventing the wheel"?

Thanks!

Bill

[DavidF]

Ive been looking into this as well, im tired of trying to remove the pla support from pla. Would be nice to gave some water soluabale support material. Man just think of the thigs you could do! So wheres some video of the dual extruders in operation??

[Eaglezsoar]

Hello to all.

I have been watching this thread with great interest. I hope to use dual extruders with the second extruder dedicated for printing HIPS support material.

How has progress gone with the setups and configurations described above?

Would it be helpful if I developed my own ideas and added my experiences to this mix, or would I be "re-inventing the wheel"?

Thanks!

Bill

From past experience with your writings, I think you would be doing us all a favor by documenting your ideas. I'd like to read about them.

[pyrophreek]

I am planning to post some photos of my setup soon, but I am actually running into an interesting problem, and I was hoping someone might have a solution. I am getting insufficient extrusion from the second extruder, and when I watch carefully, the motor appears to be moving back and forth rather than properly extruding. All of the connections are good, each extruder works fine on its own, but when I try to print with both, it starts to severely underextrude. I have gone through everything, and I even put a fan to cool the RAMB0 as I thought maybe it was a heat issue affecting the stepper drivers.

[pyrophreek]

A teaser of the results I am getting now.

Rostock Max with add an ezstruder
stock platform with one printed part for dual extruder attachment

[Bill Havins]

Thanks for the comment, Eaglezsoar. I may not get all of the details exactly right the first time (so much to know!) and appreciate comments from others. We're all still learning about this strange and incredible machine.

Today is the day that I begin serious development. Believe it or not, I am going to design my dual head platform using two "Steve's Extruders." When I ordered my Rostock MAX almost a year ago I ordered the second extruder at the same time; I've got it - I'm going to use it. Anyway, the one I have been using all these months has worked fine.

My Rostock MAX is almost "bone stock" including the all-too-flexible platform arms that cause some people to experience the "Delta Arms Blues." Mine have worked just fine.

Here's where my thoughts have been going. I want a rigid platform to hold both hotends. And, I want both hotends held perpendicular to the build plate. Finally, I want the platform to bolt directly to the Rostock MAX hotend platform. I'm not worried about losing Z height (I don't print basketballs).

Here's a Thingiverse file of the design I printed today (the link includes a photo of both hotends installed): http://www.thingiverse.com/thing:243270.

When you look at the photo you may question if the hotends are touching. Well, yes and no. The contact area is so small that I don't anticipate any more heat loss from the active hotend than what occurs with normal convection. But, I'll trying printing tomorrow and we'll see if the inactive hotend actually "cools" the one in use.

Once I get alignment as close as I can (shimming where needed), and after I get a .5mm nozzle for my second hotend, I'll begin to tweak the electronics to see if I can use both extruders the way I want.

Ugh! This is work!

Bill

[Eaglezsoar]

It will be interesting to see what happens with those touching like that. You are correct when you say the point of contact is minimal.
In my opinion they should work fine. The plate is definitely thick and strong enough, there won't be any flexing with that. I think that
it is a good thing that your Max is bone stock. You are probably one of the few that didn't buy into all of the upgrades that cost a lot of
money and you print along fine. Keep us informed on your progress with your dual head.

[Bill Havins]

I have my dual head configuration installed and am beginning tests. My new Z height appears to be 319.95mm. So, I gave up roughly 40mm of Z height by installing my hotends this way. There is no appreciable difference in the Z positions of the two nozzles (i.e., they are at the same height).

By the way, the hotends do not touch each other (see earlier post, above). In my original installation I put #6 washers under the locknuts; the OD of these washers hit the hotends, shifting them toward each other. I replaced the #6 washers with 4mm washers (they have an OD of 8mm) and now there is an approximate .15mm between the hotends. Live and learn.

I'll post the results of my tests in a "stream of consciousness" style (as they occur).

Bill

[Bill Havins]

I have a print running using both extruders! What a Rube Goldberg-sounding machine this is! Incredible.

The print is a two level, 20mm square hollow "tube." The walls of this design were developed 1mm thick so I could get a real good sense of alignment errors; I can already see that my X offset needs to be bumped in about .1mm on each side. The nozzle heights appear well-aligned without any shimming using my simple dual hotend mounting plate.

Getting the code sorted out to get all of the components working took a review of all of the threads on this forum, a request for help (Thanks, Eaglezsoar!), and discovery of two incorrect #define statements in Repetier .83. But now we're cooking!

Photos of the first print when it's done (not beautiful...it's a work in progress).

Bill

[Bill Havins]

Following are photos of my first dual extruder print. The two parts of this design are a hollow box (printed in white) measuring 20mm X 20mm X 20mm; it has 1mm thick walls. The other part (printed in blue) is a square tube measuring 20 X 20 X 20mm with 1mm thick walls.

I sliced the .stls with Cura 14.01, and selected both the "Ooze Shield" and the "Wipe and Prime Tower." The "Ooze Shield" surrounds the print. The "Wipe and Prime Tower" is at the rear left corner of the print.

I still need to adjust flow control on the blue filament. I also need to tweak the X and Y Offsets by about .1mm on both extruders.

Progress!

Bill

[Eaglezsoar]

Looking good Bill. Doesn't it feel good when you get something working?
The prints look good, with a little more tweaking they will look fine.

[Bill Havins]

For a first print I am really pleased! Thanks for your help with this.

Bill

[pyrophreek]

So I have been working with dual extruders for a while now, and the other day my extruders both died. Couldn't figure out why they wouldn't heat up. Finally after testing everything, I found that the fuse had blown. After some back of the envelope math I realized that running two extruders with the stock Ramb0 isn't a good idea, at least with the 5A fuses provided. Since two extruders require 3A each, this just exceeds the fuse rating. Turns out the Ramb0 can work with either a 5A or 10A fuse, so I have put in an order at Mouser (http://ca.mouser.com/ProductDetail/Litt ... R6%2fQo%3d) for some 10A replacements. Just thought I would share.

[fehknt]

I know there is a re-designed platform posted but I was wondering if anyone knew WHY the stock platform rotates slightly? I'd love to fix this minor but frustrating problem without replacing all my arms and completely rebuilding my end effector. I'm using http://www.thingiverse.com/thing:214536 and it is perfect near the center of the bed or moving orthogonally to the extruder separation axis, but I'm seeing the platform rotate slightly as it travels along the axis of separation. It's really killing my ability to print successfully even single-extruder. Tightening belts, re-leveling delta towers, checking all ujoints for free rotation and re-calibrating the bed radius has been done and only minor adjustments performed (with correspondingly minor results). So far my best bet has been to mis-level the extruders so the one I'm not using is out of the way just enough but I can't dual-extrude big objects like that!

[pyrophreek]

do you have belt tensioners installed? that helped alot for me.
http://www.thingiverse.com/thing:87463

[JohnStack]

I have the belt tensioners installed too. Might help.

Also, you made me think of something:

With all of the dual extruders being made, I'm wondering why someone hasn't designed a whole new effector base with different positions for the arms. You might lose an inch of circumference but keep the height about where it is with stock hot ends. Not sure...

[Eaglezsoar]

I have the belt tensioners installed too. Might help.

Also, you made me think of something:

With all of the dual extruders being made, I'm wondering why someone hasn't designed a whole new effector base with different positions for the arms. You might lose an inch of circumference but keep the height about where it is with stock hot ends. Not sure...

Have you seen the dual effectors on Thingiverse for the Rostock series?

[JohnStack]

With the exception of Mr. Haven's design, all of them are below the arms, aren't they?

What am I missing?

http://www.thingiverse.com/search?q=Ros ... x+Dual&sa=

[Eaglezsoar]

With the exception of Mr. Haven's design, all of them are below the arms, aren't they?

What am I missing?

http://www.thingiverse.com/search?q=Ros ... x+Dual&sa=

You are correct, they are below the arms. It would be difficult to design one that fits above the effector simply because there is not enough space.

[fehknt]

@pyrophreek, no I don't have those yet but it's certainly on my to-do list. It was fine with single extruders so I thought it wouldn't be a problem but maybe it is, after all re-tightening the belts did cause the most improvement I've seen yet (almost done with a 4hr single extruder print), so I'll bump those to the top of the list!

[JohnStack]

So, a new effector design - might shave off an inch in circumference...