DXU - Efficient Dual Extrusion Upgrade for UM2+

[gr5 2,173]

On 12/7/2018 at 6:20 PM, ProSharp said:

Wouldn’t it be very expensive to upgrade a umo+ with the Mark 2? Compared to this solution with a few tweaks

Ultimaker tried for years to get two heads to work in the UM2 and it worked - sort of.  It would work sometimes.  But they did a lot of testing and one of the problems was excess heat with two hot ends in there (pla wouldn't cool completely and would jam up in the upper end of the print head) and the other problem was that the inactive nozzle would leak filament into the print which is particularly ugly with 2 color prints.  The solution worked - but not great.

 

If you want a really good solution then go for the mark2 method where either head can leak a little without messing up the print.

 

[edit below]

 

Oops.  I got DXU confused with the simpler dual dozzle um2 solution.  DXU looks much better with it's ability to lift a nozzle and better heat control.  This looks just as good as um3.  Not sure if DXU or mark2 is better but both appear to be good solutions.

[alexjx 8]

Interesting, I've been using DXU for a month, but didn't notice the issue mentioned here.

I recognize mark2 is a great design, and what makes other solutions like DXU possible.

However, it doesn't make sense to rule out other also good solutions.

 

The heat breaker that DXU uses also works well enough to handle two nozzles.

I could use a stronger fan to cool them. I'm using the 2510 variant and observed the cooldown time is much shorter than the original head. I printed regular PC in one head  @ 290C, and loaded PLA in another, with an enclosure. Under this situation, the PLA in another head didn't deform enough to jam it.

 

As the leaking, I think Cura's standby temperature did a great job.

 

We are talking about modifications, there is a trade-off. The thing I believe mark2 made is space. 

The extra head will take up a much larger space than what DXU takes. 

I think the downside of DXU is really the source of material... It is not so easy to get as mark2.

Edited March 4, 2019 by alexjx

[qwerty8224 16]

GR5

I do not want to offend you, but it seems to me that you are not pursuing a good goal - to say that one is better than the other, and give an example of the testing that was. You are an adult and should understand that these are two different approaches to cooling. I will explain to inexperienced people (like you)

UM2 (which has been tested) uses cooling on one plate, that is, 1 nozzle through this plate heats the other nozzle. DXU uses a separate cooling system for each nozzle. There is a separate radiator. Such a system costs UM3 and S5, and the temperature of the first or second nozzle is not connected to each other.
I think for a full understanding, you can just say that the cooling system costs from UM3

 

for cooling radiators I recommend Sunon fans Gm0502PEV1 

selected 1 means flow rate 1 strongly 3 weakly there is also a fan Sunon 1 cm thick but pay attention to 1 at the end.

And yes, I am very grateful to everyone who worked on the project MARK2 and DXU  for the work done and the work.

Edited March 5, 2019 by qwerty8224

[burdickjp 6]

I am interested in helping with this project. I'd like to design and manufacture the heat break parts to suit both 1.75 and 2.85 mm filament. I should be able to make them compatible with Olsen and 3D Solex blocks.

[Garufa 11]

Talking about sourcing of materials being difficult- Aliexpress is selling the following for UM3 and perhaps the DXU can work with it

https://www.aliexpress.com/item/-/32957845038.html

[Turbo-Power 3]

Sanbrother sells parts for DXU on ali.

[superdave42 13]

Awesome sauce !!   I just found this thread.

 

As some of you have seen,   I am trying to convert my UM2+   to a UM3+ sorta.

 

I already did Mark2 conversion and that just works great!.

 

however,  I wanted to run the UM3 head with the cores,  so I bought the head assembly and some cores,   bout the Olimex board etc...   

Now I see I can just use the UM2 head and ther DXU modified MK2 code  to possibly get the dual extrusion working with the shift lever.

 

I guess what I really learned form this thread was that I don;t need the damn UM3 electronics to make the UM3 head work.   sure won;t have the RGB LED function on the cores   or the data etc.    but it should mechanically work fine.

 

Cool,   I may give this a shot over the weekend.

 

now if it was possible to get the capacitive level sensor working in the UM3 head  🙂   I need to check into that,  probably possible.

 

 

[yyh1002 60]

On 3/4/2019 at 1:14 AM, Garufa said:

Thanks for your posts, I have ordered most parts and will try to make the convertion for my UM2+ Extended. What's the difference between the two extended firmware versions ?

You can check out this post for the difference. Firmware 17.10.2 is for v1.1 update. 17.10.1 is the original. 

 

[Garufa 11]

On 3/23/2019 at 4:46 AM, yyh1002 said:

You can check out this post for the difference. Firmware 17.10.2 is for v1.1 update. 17.10.1 is the original. 

yyh1002 thank you, the more I check the parts and design, I appreciate more the work and effort put into the DXU, soon I will have all parts from china, thank you again

 

[ultiarjan 1,223]

On 3/21/2019 at 9:19 PM, superdave42 said:

guess what I really learned form this thread was that I don;t need the damn UM3 electronics to make the UM3 head work.   

You can use the um3 head on the um2 by simply making a PCB with only the connectors touching the core electronics and wire to the mainboards heater and pt100 connection. No need for any fancy electronics. I've shown it here somewhere including the link to the correct component but on the phone and too lazy to find a link now 🙂

[burdickjp 6]

1 hour ago, ultiarjan said:

You can use the um3 head on the um2 by simply making a PCB with only the connectors touching the core electronics and wire to the mainboards heater and pt100 connection. No need for any fancy electronics. I've shown it here somewhere including the link to the correct component but on the phone and too lazy to find a link now 🙂

 

I'm thoroughly interested in doing this. I thought about designing and making the PCB necessary, but couldn't find the correct pogo pins. Care to share?

[gr5 2,173]

first item listed by google was the right link: 

 

 

[ultiarjan 1,223]

thanks @gr5

 

and this link is also relevant to get the parts....

 

link to connector:

https://uk.farnell.com/avx-interconnect/9155005003016/connector-battery-5-pos-2-3mm/dp/9728449

 

[ultiarjan 1,223]

 

I've also been working on a better single core design for Ultimaker2 for ages, with a metal 3d printed bottom plate. I still need to work on the bottom plate holding the front fan, but with the spare time I have atm it will probably still take ages 😞

 

 

 

[rajilpahuja 38]

Getting Ready 😉😊 all parts in peek and ultem1010.....now just waiting for them parts, hopefully this works even better than mark2 😉

[yyh1002 60]

On 3/30/2019 at 12:45 PM, Garufa said:

yyh1002 thank you, the more I check the parts and design, I appreciate more the work and effort put into the DXU, soon I will have all parts from china, thank you again

Cheers

 

1 hour ago, rajilpahuja said:

Wow, that the best PEEK print quality I've ever seen. 

[rajilpahuja 38]

34 minutes ago, yyh1002 said:

Cheers

 

Wow, that the best PEEK print quality I've ever seen. 

Thanks my Man..... Peek and Ultem is my specialisation 😉 I saw u made some changes might need to re-print that dock 😊

[yyh1002 60]

I pushed v1.5 update on GitHub. It is mainly to replace the 19mm short bearing with a long one for better reliability. 

 

Changes:

1. Both X and Y bearings are now both 35mm long, same as the original UM2 printhead. It is more stable and reliable. The previous 19mm Y bearing had a few downsides: only misumi sells ones with sufficient build quality, they wear faster than long bearing, etc. To make proper space for the long bearing, I had to increase the X offset of nozzles from 18mm to 19mm, and the housing from 35x35 to 38x38. This resulted in 2mm less X print area but it is well worth it. 

2. New fan shroud design. Blower fan changed from 3015 to 3510. Homemade aluminium cover by soda can at the bottom. The fan shroud can be printed with lower temp materials such as modified PC (heat resistance of 90C). 3510 12v fan is easier to source with more consistent stock. For those of you who already bought the 3015 fans, there is still a fan shroud variant to use 3015 with v1.5. 

3. Hotend fan changed from 2510 to 3010. Not really for performance improvement. 3010 5v is much easier to source and cheaper. 

4. Lever dock is simplified with only one tab. This gives the lever freedom to sweep back at full speed, not limited by the travel speed of printhead. Nozzle 2 falls back to it's position with optimal momentum. 

5. BOM is hence modified with the new fans and bearing. The hotend, spring and bolts stays the same. 

6. Firmware update for v1.5 moved to dedicated repository. 

 

I may or may not update the assembly images because people can still figure out how to assemble v1.5 based on the original images. 

I'll upload the jig and instructions for making the aluminium bottom cover later. 

 

[rajilpahuja 38]

56 minutes ago, yyh1002 said:

I pushed v1.5 update on GitHub. It is mainly to replace the 19mm short bearing with a long one for better reliability. 

 

Changes:

1. Both X and Y bearings are now both 35mm long, same as the original UM2 printhead. It is more stable and reliable. The previous 19mm Y bearing had a few downsides: only misumi sells ones with sufficient build quality, they wear faster than long bearing, etc. To make proper space for the long bearing, I had to increase the X offset of nozzles from 18mm to 19mm, and the housing from 35x35 to 38x38. This resulted in 2mm less X print area but it is well worth it. 

2. New fan shroud design. Blower fan changed from 3015 to 3510. Homemade aluminium cover by soda can at the bottom. The fan shroud can be printed with lower temp materials such as modified PC (heat resistance of 90C). 3510 12v fan is easier to source with more consistent stock. For those of you who already bought the 3015 fans, there is still a fan shroud variant to use 3015 with v1.5. 

3. Hotend fan changed from 2510 to 3010. Not really for performance improvement. 3010 5v is much easier to source and cheaper. 

4. Lever dock is simplified with only one tab. This gives the lever freedom to sweep back at full speed, not limited by the travel speed of printhead. Nozzle 2 falls back to it's position with optimal momentum. 

5. BOM is hence modified with the new fans and bearing. The hotend, spring and bolts stays the same. 

6. Firmware update for v1.5 moved to dedicated repository. 

 

I may or may not update the assembly images because people can still figure out how to assemble v1.5 based on the original images. 

I'll upload the jig and instructions for making the aluminium bottom cover later. 

 

So need to maybe print the head again 😆, maybe i will try to use first what i made and see how it functions, if there is issues i guess can change the head only maybe its better to have the bigger cooling fans, i guess since my fan shroud is in peek, i dont need metal cause peek takes 280C without load easy 😉

[yyh1002 60]

9 minutes ago, rajilpahuja said:

So need to maybe print the head again 😆, maybe i will try to use first what i made and see how it functions, if there is issues i guess can change the head only maybe its better to have the bigger cooling fans, i guess since my fan shroud is in peek, i dont need metal cause peek takes 280C without load easy 😉

You can totally try the existing version first. Short bearing should last at least several months. For the blower fan, 3015 works as good as 3510 thanks to more accurate duct aiming the nozzle and better fan shape. 

[burdickjp 6]

4 minutes ago, yyh1002 said:

You can totally try the existing version first. Short bearing should last at least several months. For the blower fan, 3015 works as good as 3510 thanks to more accurate duct aiming the nozzle and better fan shape. 

 

If the short bearings are wearing then something is wrong. The Ultimaker 3 uses a short bearing on the Y axis rod and lasts a long while. Maybe alignment isn't sufficient and it's wearing because of misalignment?

[yyh1002 60]

5 minutes ago, burdickjp said:

 

If the short bearings are wearing then something is wrong. The Ultimaker 3 uses a short bearing on the Y axis rod and lasts a long while. Maybe alignment isn't sufficient and it's wearing because of misalignment?

Misalignment is one factor. IMO it is also because the short bearing is off center and the dock apply quite some force to the head during nozzle change. The force transfers to lateral load at the bearing. Looking at example applications of LM6 bearings, a single short bearing for one axis with such a thin rod really seem to be pushing the limit. Ultimaker did a good job getting it to work with their quality control. For individual tinkerers I would try to avoid this situation. 

[qwerty8224 16]

For those of you who already bought the 3015 fans, there is still a fan shroud variant to use 3015 with v1.5. 

 

Unfortunately I can not find it (((

[yyh1002 60]

2 hours ago, qwerty8224 said:

For those of you who already bought the 3015 fans, there is still a fan shroud variant to use 3015 with v1.5. 

 

Unfortunately I can not find it (((

Sorry, it was left out by accident. It's now there. 

[qwerty8224 16]

Sorry, it was left out by accident. It's now there.

 

thank )))

Edited April 4, 2019 by qwerty8224