Stupid question… the distance spacer; is it required? I’m not sure I can machine that piece. Would there be an adverse actions to doing what you propose and leaving it out?
Also, I know your research was J1-specific… I have a DX for my A350T… Judging by the pictures of the hot ends they look exactly the same with different colors. Can you see any limitations to giving this a try with a DX? We’re experiencing clogging too.
Chris
I have printed several kilograms of PA, PA-GF, and PA-CF with absolutely flawless results using temps up to 275C (Nylon, Glass reinforced Nylon, and Carbon reinforced Nylon). I have also printed several kilograms of Ingeo 870 based “Pro” PLA at temps from 225C to 240C, again with flawless results.
The ONLY material that has given me any clogging issues is silk PLA, which tends to use lower temps.
If you leave that one out, you cannot tighten the heat break - so yes, it is required unless you want a freely rotating heat block 
Check the “Assembly” picture.
Lucky you I had these clogging issues with all PLA variants I use, and PETG as well. But I guess Snapmaker partially solved the issue by significantly lowering the retraction values. - when I started using the J1, the slicer settings were 2mm retract and 90 retracts every… 1.5mm if I remember correctly. That caused really reliable clogging.
Even at 1mm it’s still causing significant clogging for both the artisan/Ax50 DX owners. I have a spare set of hot ends I’m looking for suitable brass pipe now.
@Mechanikus
I don’t quite understand D5/D2… is that the OD/ID of the pipe? Your schematic indicates it’s 4,5mm and there’s no minimum for the inner diameter? It just needs to survive the heat break being installed?
Thank you for answering my amatuer questions.
The technical drawing on the “where do I get that distance roll” slide is a half section - only the lower side shows the inner design of the part.
D5/D2 means the inner diameter of the pipe would be 2mm (to be drilled out to 2.3mm ± 0,05mm - 2.2mm would probalby work as well) and the outer diameter is 5mm which you need to reduce to 4.95mm that is you can slide it into the heat sink.
The chamfers on the outside facilitate insertion. do not make the one facing towards the heat break too large - the contact surface is very small which is the main reason that I use brass - aluminium or even plastic does not survive the surface pressure you get when tightening the assembly.
The chamfers on the inside help guiding the filament though the hole.
Exactly what I wanted to know. Thank you. I really appreciate the effort you did and your comments. This is what makes these hobbies fun.
Chris
For the most part, I am not using any of the default slicer profiles. I am using Cura with settings similar to what I know works with my other printers. In general, I am using lower speeds with thinner layers with a focus on quality over quantity.
My printer is completely stock, except for the addition of more thermal paste to the cold side of the heatbreak and the switch to hardened E3D Nozzle X nozzles.(J1 Nozzle Upgrade to E3D V6)
Now i have tested my change fully. With standard J1 but with slice engineering copper head hot end with bondtech CHT this print stopped at 60%. I restarted it 7 times before i gave up the clogging stopps.
Afte this i installed my mk8 slice engineering bi metal heat break and it printed straight throe for 26h and no stopps.
My settings where 0.6 nozzle 100mm/s 0.1 layer hight and 215 degrees temp and travel speed 350mm/s.
Probably will start testing higher speeds now 
there you go, it’s great that it works for you now too.
Yup, I still have…
@nnowak
Download here…
https://www.file2send.eu/de/download/m511fYSqEfLwVcrKrAPWwmuo7lkFXUXZXyaGZcJazA43x3LLwx7zTA5pasJmrcql
Thank you for posting this. Sorry, I had missed the part that you were using the XY Belt tool for this print testing as you had mentioned a cube in one of your other posts. Aside from changes to print temperature, were you using the stock Snapmaker GCode for the belt tool?
No more clogging, just a simple fix
take out the Hotend from Extruder Heads, replace the cooling fan from heatsink with a better one with more Airflow. you can also alow them more airflow from outside and print a cover with more vent holes and on the other side where the fan blows the air out the hotend you can remove brakets from the cover, so the air can be better go out and its reduce fent noise
Put thermal Grizzly Heatsink Paste on the Heatbrak.
No more clogging here.
Printed PLA, PLA silk, PETG, HIPS, PVA, TPU and ASA.
Some other tests are running.
So i only need new rails, the rest seems ok now
Did you adjust the distance between the linear rail and the gray rail before tightening the screws, e.g. by underlaying a 0.5mm thick washer or by means of a feeler gauge or did you only tighten it evenly and the linear rail has centered by itself?
Hast du vor dem Anziehen der Schrauben den Abstand zwischen Linearschiene und der grauen Schiene justiert z.B. durch Unterlegen einer 0,5mm dicken Unterlegscheibe oder mittels Fühlerlehre oder hast du sie nur gleichmäßig angezogen und die Linearschiene hat sich von selbst zentriert?
On the rails I have done nothing. I only changed the fans from the heatsink
My question was a reply to the post from @wfux 
I loosened the screws and inserted a 0.5 mm plate under and above the rail, then tightened it.
German:
Ich habe die Schrauben gelöst und unter und über der Schiene ein Plättchen mit 0,5 mm eingelegt, dann festgezogen.
Ordered everything. I’m gonna give it a go. I have the a350/DX model and we’re having clogs just like you guys are.
Maybe it’s a solution for everyone. Hardest part is the spacer.
Stupid question, instead of a spacer couldn’t we drill a set screw into the thermal block to hold it in place like snappy does on theirs?
Im sorry, I only replay from email 
I would leave that, the spacer is no problem at all.
If necessary, ask someone who can do it.
