Detailed Documentation of our hardware and software mods for reliable printing

[Jamezracer 10]

Eldrick- That's another good way to get close. I like to set my esteps such that an extrusion multoplier of 1.00 gives ideal results. Then I can bump it up and down by a percent if I purposely want under or overextrsuion. Additionally our printers are used by students who like to fiddle with settings that they shouldn't so having the multiplier at 1.00 helps.

I'm glad your fan duct fit. What screws did you use?

Edited October 27, 2015 by Guest
Spilling

[eldrick 65]

I'm glad your fan duct fit. What screws did you use?

I just put a dab of superglue on two of the corners to hold the fan to the duct.

[BrayChristopher 36]

Does anybody have an accurate model of the bottom part of the print head?

I don't fancy removing a small notch or two from my origional part so would rather print a modified replacement.

How bad of an idea would it be to run all the wiring "outside" of the head? I am thinking of making a little guide part that hangs on the two rear thumb screws.

Our UM2E is a work machine, so I am hesitant to "hack" it too much.

I think I will try to queue up several "head" upgrades (Rear Fan Duct, Rear Cable Guide, Olsson Block, Side Fan Ducts), and do them all at once.

[ultiarjan 1,223]

How bad of an idea would it be to run all the wiring "outside" of the head?

Except for ruining the machines good looks no problem at all when in the home position you see how much space you have at the back. But I can't see why you would do this with the normal UM2 head?

[BrayChristopher 36]

But I can't see why you would do this with the normal UM2 head?

The rear fan duct by Jamezracer closes off the small opening in the bottom of the head assembly where the wires exit.

- Jamezracer made little notches in the bottom plastic part of the bearing housing to let the wires out.

- Izzy made a new version of the bottom plastic part with access ports for the wires to

 

I'm trying to find a slightly less invasive option. I like the idea of the rear fan duct, but if it is going to get too involved, I can live with out it.

[BrayChristopher 36]

 when in the home position you see how much space you have at the back.

 

For reference.

I measure 9mm in the back and 7mm on the side.

[LePaul 322]

That was a fantastic read, with a lot of positive improvement points for Ultimaker and customers

I was curious about the Bowden tube upgrade, how do you countersink and complete the modifications described? I couldn't sort that out in my mind

[SandervG 1,521]

I have read it too, very informative and many thanks for taking the efforts of writing it down.

I think he means you can use a knife or some sorts and make the entry of the bowden tube wider at the feeder.

If you look at your bowden tube, it is wider at the 'bottom'.

Edited October 4, 2016 by Guest

[JohnFox 25]

Hot end fan spacer.

Just printed the fan spacer but on my UM2 this spacer is far too thick. It pushes the fan back by about 5mm and thus prevents the heater and thermocouple cables from entering the black plastic bearing shell. If you force it, the cables will be damaged. I tried reducing the thickness to about 2mm but still the cables would be crushed by the bearing holder shell.

The air flow problem is not as serious as it sounds. Yes, there are only two full slots where the air flows in but those slots, ( at least the left one ) are in the perfect place to cool the PTFE coupler. It's is possible that by allowing the air to flow though all the slots instead of two, it may reduce the flow of air around the PTFE coupler. My coupler doesn't seem to get too hot anyway.

[izzy 33]

Hi John, on YouMagine I've put a modified bottom housing that has some cable outs, there is also a modified heatsink fan duct that allows for the use of fan ducts that swivel away from the print head. Hope that helps, Izzy

https://www.youmagine.com/designs/print-head-bottom-modification

[Jamezracer 10]

Looks slick Izzy! I'll give it a go when I'm back in the lab.

JohnFox - The youmagine page says you have to cut away plastic to clear the wires. Izzy seems to have come up with a better solution though!

[JohnFox 25]

Just downloaded Izzy's files. Thanks, that should sort it!

 

Looks slick Izzy! I'll give it a go when I'm back in the lab.

JohnFox - The youmagine page says you have to cut away plastic  to clear the wires. Izzy seems to have come up with a better solution though!

 

[eldrick 65]

Just printed the fan spacer but on my UM2 this spacer is far too thick. It pushes the fan back by about 5mm and thus prevents the heater and thermocouple cables from entering the black plastic bearing shell.

There must have been some change in the UM2 since a 18 months ago - on mine the fan duct fit fine, with enough room at the top for the wiring.

[alexk195 0]

Hi all,

I experience same problems with the feeder as described in the document. So far the only things that helped a was to change filament (original blue filament was a crap, sorry).

But I still not able to print reliably with more than 1.5mm^3/s!!! Either my feeder motor has not enough torque or the friction in the bowden system is too high.

So I'm very interested in the upgrade: "flipping feeder, new bolt, reverting feeder direction in firmware." I could compile the new firmware with inverted feeder direction and adjusted extrusion ratio but I see it as last resort and not as optimal solution. Is there no other way to "teach" cura generate according Gcode? For example provide negative number for "E-Steps per 1mm filament".

[alexk195 0]

Now I get fantastic results! My Ultimaker never printed better!

I've replaced the bolt, flipped the feeder and bult custom firmware with inverted E-Axis and 1500mA. No bowden tube change. The "extrusion testing tower" printed before looked ok up to 4mm^3/s. With this simple changes the tower looks ok up to 10mm^3/s but I was able to hear 3-4 skipped steps of extruder in the 10mm area (at 210°C ).  At 200°C  I can hear skipped steps at 7mm, so 6mm is my speed at 200.

Edited November 14, 2015 by Guest

[oceanblue72 5]

Thanks for this very usefull report!

I'm using an other feeder with a MK7 gear. So i have to downgrade from 282 to 202,5 steps. How / where can i change the e steppings?

Thanks

Marcus

[Jamezracer 10]

Thanks for this very usefull report!

I'm using an other feeder with a MK7 gear. So i have to downgrade from 282 to 202,5 steps. How / where can i change the e steppings?

Thanks

Marcus

 

In the paper I state "Change feeder motor steps/mm on line 366 of Configuration.h"

[bondtech 25]

Hi, i would like to present the Bondtech Extruder for you if you haven't seen it yet, it uses a dual drive gear that grip the filament from both sides that eliminates grinding and slipping problems, it also uses a planetary gearbox that increases torque and precision, it uses 492.45 steps / mm filament.

I have made a custom firmware available with the needed modifications and there is a Assembly guide available with step by step instructions of how to install it.

 

Feel free to ask questions.

[LePaul 322]

With the release of the Ultimaker 2+ and it's new feeder, I wonder how it will compare to yours?

And the video...what's with the funeral pipe organ? Sounds like Flash Gordon died

Edited January 6, 2016 by Guest

[eldrick 65]

Do you really think anyone will ever watch over seven minutes of a head moving?

Also, the extruder could be lower-friction if you rotated it, so that the filament could feed back from the left side of the printer, putting the natural filament curl in line with the curve of the Bowden tube.

I'm assuming that it would take a 35w or higher heater to deliver the increased speeds.

Edited January 6, 2016 by Guest

[bondtech 25]

@eldrick of course I do not think that people will look on the entire video for 7 minutes but instead use the fast-forward button, I just wanted to film the entire sequence so everyone can see that it is not edited and changed, but it might have been better if i cut it down, thanks for the comment. The changed position could be better but I wanted to use the existing mounting holes in order to make the installation easy, it might be possible to design a mount so it sits on the left side and still use the existing mounting holes.

Yes the machine is upgraded with Olsson block and also the 35W heater.

Interesting is that I managed 40 mm/s with the same material roll, temperature, extrusion width, layerheight with the original UM extruder without underextrusion.

[Torgeir 243]

Hi James,

I have to say, this is one of the best report I've seen in this forum and cant really understand why this one is not more addressed! Here is a lot of tip of how to improve and what failed, ofc. we all may have different experience but most of the important things is in here IMO.

(I'll have to say, I never had any problem with the feeder flow test, I could print the whole cylinder with a standard feeder and the standard extruder head with no issues. Maybe cause I used a 1.8 deg. (200) stepper motor geared down to 1/2 at the feeder wheel (more torque). )

I might have read this before, but missed the essence at that time, however, yesterday I've read it and today I printed the adapter for the hot end fan -and also installed it..

I have always wanted to do something with the partially blocked inlet (wires from heater and the temp. probe) side of the fan. Also the outlet had this issue, as the fan itself blocked some of the cooling ribs.

This modification is much better than it seems to be, cause it will deliver better cooling to the cold part of the hot end -preventing filament to "glue stuck" on the cold side during cooling down, or during a long print. Also, if you plan to isolate the extruder in order to have more of the total energy for melting filament and not spread heat to the surrounding parts/environment, you must have better cooling on the cold part of the extruder.

I have not installed the second (cheap Chinese) extruder head I have, on the printer, but I've printed Laberns Single nozzle heath scroud and installed this one as well with an Olson block well insulated in here as I installed a 25W heater element. Thanks Labern, your heath scroud do not need any alu tape to adjust the airflow, the pressure center is right in the middle of the nozzle. Well done!!!

I've tested a few, but this is the best one -and best looking..

Here's a picture of the extruder.

Thanks for sharing your experience James.

Torgeir.

[ultiarjan 1,223]

What's that material you used to isolate the block? what temperature can it handle? looks like a great solution to me!

[Torgeir 243]

Hi Ultiarjan,

Thanks.

The insulation material is «Absorbent of white fiberglass used as wick in ethanol stoves».  This material have another good properties for us to use as it is an excellent high temp insulator. I've found this material some time ago, but did not have a good solution to prevent that the heath climb upward into the bowden tube and gluing the filament.  -Well, until I saw this tread.

I've found some items that might be useful for such high temperature related design. All of them is bought at «Biltema», a supermarket for almost everything that's found in the Scandinavian countries (originated from Sweden).

There is a thermic glue that’s cope with temperatures up to 1100 deg Celsius! I've planned to glue some alum foil on the lo side of Laberns «dual fan duct bracket» in order to deflect some radiation heath from the heat bed. (Do not know how this will work on PLA or Alum foil, but will do some test later on.)

The last one is a tube of high temp «instant gasket», that's also tend to vulcanize in room temperature. This silicone stand temperatures up to max. 310 deg. Celsius. Might be something to protect the nozzle tip with? (Reefer to another tread ongoing).

As a little «prove» of that if this insulation might be good enough to be used for this purpose, have a look at the attached pictures.

The tip temperature of the soldering iron is around 350 deg. Celsius.  The brown area on the insulation “mat” is remains of the insulation sleeve at the thermocouple.

NOTE.

Another thing I forgot to mention yesterday is that, I did not have any problem to fit the fan duct adapter into place. No need to remove material in any way, just a drill bit 2.5 mm to clear the two attacment holes at bottom side.

Thanks

Torgeir.

Edited September 29, 2016 by Guest

[ultiarjan 1,223]

Ha ha you're so brave to test with your bare hand...