Best UMO hotend + nozzle?

[printerfan 5]

I have an UMO with dual extrusion and have decided to completely replace both of my hotends in their entirety (Peek, aluminum block, nozzle, ect.). Long story short, I bought my UMO used and its had issues since day 1, which I think may have been related to the previous owner using cheap aftermarket parts for the hotend and I just want to have a fresh start and see if I can improve my prints.

Given I have UMO with dual extrusion, what is the best hotend and nozzle setup for me to install?

Should I buy 2 new hotend packs from ultimaker or should I buy an "upgraded" hotend from a 3rd party?

[SandervG 1,521]

Hi!

What are the problems you have been experiencing?

And have other parts been replaced as well, in order to have it coop with the alternative hot ends or just the hot end?

[printerfan 5]

Its been a broad series of issies.  Difficulty bed leveling (official heated bed upgrade installed), clogging, poor print quality (though have got a few prints with good quality), bowden tube detaching from extruder after multi-hour print, prints prematurely stopping, ect.

As far as other parts being replaced, I know some part of the hotend were replaced by the previous owner since I found multiple clogged and broken brass hotend barrels and nozzles in the "spare parts" bag he included. Whether he used official ultimaker or cheap chinese to replace the parts he broke is not known to me.

Edited September 21, 2015 by Guest

[SandervG 1,521]

You could upload some pictures of the hot end from different angles, and the feeder as well.

We could have a look at what is original or not.

[printerfan 5]

Can you actually tell the difference between the chinese knock-off nozzle, aluminum block, and hotend and official UM from just a picture?

[SandervG 1,521]

It depends on how well they are copied

And maybe there are also other parts replaced, which only work with this hot end like the thermocouple or heater cartridge.

[tommyph1208 55]

I would say don't buy new hotend packs (no offense Ultimaker)

They are very expensive, somewhat limited in their design in terms of what types of material they can print, and possibly you will end up having the same problems as the machines previous user... At that point, you have to yourself, decide if you want to go with expensive original UM replacement parts or cheap chinese ones.

A very popular replacement hotend for the UMO is the E3Dv6 (I use one myself)... Its a high quality all metal hotend with a small fan for active cooling of the cold-part, it has no peek, or anything like that, and so can run quite high temperatures for a variety of materials...

They also have a wide selection of nozzles in different diameters and materials (0.25 - 0.8mm., brass, stainless and hardened steel)

Since you are running dual extrsion, you can look into some of the options they have for that,

Namely the Chimera: http://e3d-online.com/Multi-Extrusion/Chimera

And the cyclops: http://e3d-online.com/Cyclops

Edited September 22, 2015 by Guest

[printerfan 5]

Tommy, thanks for the post. Do you have any example prints made with the chimera? In what ways do you feel the chimera may be better than buying 2 new official ultimaker hotends?

[tommyph1208 55]

No way... I just wote the longest reply ever and my iPad browser gave me an error when pressing post.... sad.

In short:

I dont own a Chimera, just a regular v6, e3d is great quality with nice details and larger flexibility in temperatures and materials than the UM hotends. Chimera is 2 hotends, but one heatsink, so i think you may be better off with alignment there too, though I dont know how much of an issue that is with two UM hotends.

[printerfan 5]

I hate when that happens... :(

The Chimera only comes in 1.75mm. How do you think 1.75mm would affect performance on an UMO?

[printerfan 5]

I also hear that PLA is difficult to work with in an all metal hotend. Have you found this to be true?

[tommyph1208 55]

I also hear that PLA is difficult to work with in an all metal hotend. Have you found this to be true?

 

Ah, did not know the Chimera was only 1.75mm., that complicates things a bit, though not a lot.

3mm., or 1.75mm., the difference should not be much... I think some people like one, and some the other.

If you search this forum, I'm sure you can find posts with people who have converted to 1.75mm. and will explain the benefits..

Regarding the PLA in all metal hotends (I've seen this postulate many times in connection with E3Ds hotends), I think it isn't true... I've printed tons of PLA on mine, and never had it clog or anything like that.

E3D have some very detailed assembly instructions, follow them to the point and you are good.

[SandervG 1,521]

I thought the point was that in a full metal hot end there is more friction or resistance with PLA.

[LePaul 321]

I had troubles with the Bowden tube on both ends with my Ultimaker Original.

This Extruder Clip made a huge difference on the end that goes to the extruder. Mine was very noisy, popping up and down but never popping off.

The end that attaches to the print head would frequently pop off. It turned out that the collet was the problem, the metal pieces were not "digging" into the Bowden tube well enough to hold it in place. Here's the part as listed on fbrc8's site.

Hope that helps with part of your questions

[tommyph1208 55]

I thought the point was that in a full metal hot end there is more friction or resistance with PLA.

 

This is not something I have experienced at all...

With the 1.75mm. E3D bowden hotends, the bowden tube actually sits all the way down to the heatbreak, further reducing any friction there might be... See this image:

Im guessing the same goes for eg. the Chimera (though I'm not sure)

Edited September 30, 2015 by Guest

[macua85 52]

My 2 pence worth...stick with the OEM hot end. Its a great design and doesn't clog if its in good order (I've had my printer for over a year, hundreds of hours printing and never replaced a part with zero clogs).

I have tried a dual e3d v6 setup, 3mm bowden. Sander is bang on the money, I have had no end of clogs and failed prints. I know others on this forum have also tried with similar results (ultiarjan). I have friends who use the 1.75mm bodwen version with no issues, probably due to the extended ptfe liner which means its not really a full metal hot end anymore. I also know people who have the 3mm version working, but not with bowden, but direct drive. This also seems to make a difference.

This is just my experience, it will almost certainly be different for others. I ended up using ultimaker hot end parts on my custom hotend (for experimental second printer) with perfect results.

Edited October 2, 2015 by Guest

[printerfan 5]

I decided to order the official ultimaker hotends because the Chimera was not offered in 3mm. Unfortunately, although I spent the extra money and ordered the official ultimaker hotend pack and official thermocouple, the official thermocouple does not fit the official aluminum block...

I don't know if this is simply a 1/1000 chance of getting an aluminum block or thermocouple that slipped through the cracks of quality control, but my thermocouple will not insert fulling into the slot and it is now firmly lodged half-way in the block...

I am rather disappointed to say the least because I ordered official parts, despite their high cost, to avoid issues such as this and yet I am again stuck without a fully functional printer. Will update as to how this gets handled.

[tommyph1208 55]

I decided to order the official ultimaker hotends because the Chimera was not offered in 3mm. Unfortunately, although I spent the extra money and ordered the official ultimaker hotend pack and official thermocouple, the official thermocouple does not fit the official aluminum block...  

I don't know if this is simply a 1/1000 chance of getting an aluminum block or thermocouple that slipped through the cracks of quality control, but my thermocouple will not insert fulling into the slot and it is now firmly lodged half-way in the block...

I am rather disappointed to say the least because I ordered official parts, despite their high cost, to avoid issues such as this and yet I am again stuck without a fully functional printer.  Will update as to how this gets handled.

 

Aw man... thats just sucky...

I know its a bit of a gamble with the hotend only half assembled and all... But if you can heat the block up a bit, you will maybe be able to pull the thermocouple out as the metal expands slightly... (be careful not to overheat it and damage the thermocouple)

Edited October 3, 2015 by Guest

[printerfan 5]

I tried pulling it out from the end I inserted it with my fingers and it caused the metal cover to pull off a little and now its frayed. I hope pulling on it didn't affect functionality, I used my hands because I figured pliers were too much of a risk to damaging it. I was able to get my allan wrench and push it out from the other end. So its out. Because my printer is used I have multiple aluminum blocks that were sent to me from the previous owner, not sure if they are aftermarket or official, but no matter as I bought 2 official aluminum blocks given I have dual extrusion and the thermocouple did not fit in any of the blocks. In the new official blocks I purchased the thermocouple at least made it about 1/3 of the way before it starts giving resistance, it will get lodged if I push it 40-50% in. The thermocouple is not able to be inserted at all in the other aluminum blocks that the previous owner included.

I have contacted the official ultimaker distributor from who I bought the parts and am awaiting a reply. Hopefully they can help me figure out what is going on or let me exchange this thermocouple for one that fits.

[printerfan 5]

As a side note, the old thermocouple that is still on my second extruder fits fine within the new offical aluminum blocks. It slides in and out with no resistance and seems like it risks sliding out during prints without the securing screw in place. So there is definitely a difference in diameter between the thermocouple I currently have on my second extruder and the new one I received.

[printerfan 5]

Update:

Replacement thermocouple arrived from Fabric8, they were quick to reply and shipped the replacement thermocouple the day they replied to my email. The replacement fit, and seems to be working fine. I'm pleased with the way they handled everything.

[printerfan 5]

Update 2:

After installing the new thermocouple and attempting an ABS print the nozzle clogged and I attempted to disassemble the hotend. Everything came off except the thermocouple which is now stuck... The last one was so large it couldn't be installed properly, the replacement fit, albeit snugly, but now after having it in the block under heat it must have expanded and now it's lodged in the block. With the previous defective thermocouple I was able to push it out from the other side with a thin tool, but this one is too far in and is not moving. Any advice?

[SandervG 1,521]

Do you need to disassemble the hot end?

If the nozzle is clogged you could also clean it with an Atomic Method?

(the description is about the Ultimaker 2 Extended, but the idea is the same for your Original)

Did you remove the screw that is suppose to hold them in place?

Is there any metal part left you could try to grab it by with a pair of pliers?

Heating and cooling doesn't help?

[printerfan 5]

Do you need to disassemble the hot end?

If the nozzle is clogged you could also clean it with an Atomic Method?

(the description is about the Ultimaker 2 Extended, but the idea is the same for your Original)

Did you remove the screw that is suppose to hold them in place?

Is there any metal part left you could try to grab it by with a pair of pliers?

Heating and cooling doesn't help?

Yes, the hotend barrel is clogged, I need to remove the peek from the block to properly clean it.  I have attempted the atomic method, it has never worked for me, the filament always snaps above the hotend and when I pull hard the rods start bending upwards and I do not wish to risk permanently deforming them.  

Yes, I removed the screw.  I tried pushing the thermocouple out from the other end using a small torx screw driver, it wouldn't budge.  

There is a little portion hanging out and I can grab it with a needle nose plier, but I fear that will damage the thermocouple.

I've tried removing it while heated, while it was cooling, and once it was completely cooled.  It did not move.

Edited October 19, 2015 by Guest

[printerfan 5]

An update: little over a year later after replacing both hotends with all official ultimaker parts. I did very little printing during the past year until the past couple months because both hotends clogged almost immediately with ABS after I installed them a year ago. I eventually was able to clear one of the nozzles out using a modified version of the Atomic Pull method and printed on and off for the past 2 months with PLA. I have had very mixed results: a lot of underextrusion and a lot of clogs (Atomic method had to be used after almost every print as the next print would not function). Now Atomic Method is coming out clean, yet I'm still experiencing significant underextrusion. I assumed the hotend coupler must be deformed, but after disassembling the hotend, the coupler looks fine.

 

What is the cause of the underextrusion, I don't know. I've cleaned the gnarled bolt, I've loosed the screw on the extruder driver, I've tightened the screw on the extruder driver, I've used brand new filament, I've cleaned the bowden tube, I've adjusted bed leveling in case it was too close and causing back pressure and I replaced the entire hotend with offical ultimaker parts. Nothing produced consistent positive results. What is consistent are clogs and underextrusion occurring at least every 2-3 prints and now unable to print.

I'm abandoning offical ultimaker parts in favor of third party parts in hopes of finally getting consistent results. I will be purchasing a 3rd party PTFE bowden tube and 3rd party hotend. Currently looking at E3D hotends, but am still looking at what is currently on the market. Will update on my results when I make my decision and get some prints going.