Nozzle swapping difficulties - screwing into heating block
I recently bought a 0.6 mm E3D high flow brass nozzle, and I'm having trouble with changing it. I printed the official tool for easy removal, and while I could remove the old brass nozzle it was tougher than I thought, the force required resulted in the PLA tool making a cut into the silicone sock.
Now I can't get either the old nozzle or the new nozzle into the heating block, the force required after a while seems excessive. So I wonder if I have stripped the threads on the heating block or something else is wrong?
Cheers in advance
RE: Nozzle swapping difficulties - screwing into heating block
WHen you were removing the old nozzle did you make sure the thumbscrews were loose? I have eighr forgotten or not loosened them enough a few times, and the nozzle gets progressively harder to remove. Plus if these are not loose it is nearly impossible to insert the new nozzle.
Now the question is if the heat block threads are damaged or have some filament melted into them. Swing the heat block down so that you can look through it. Do you see metal bits in the threads or any plastic? Are the threads of the nozzles damaged (weird shiny spots, etc)?
I find it very easy to start a nozzle slightly cross threaded if I am not holding the front edge of the block up as I insert the nozzle and start threading it in.
If the nozzle threads look OK, and the heat block looks basically OK, then with the heat block still hanging loose, thread the nozzle in from the BACK side of the heat block. The assumption being that if there is damage to the heat block threads, then this should allow you to start the nozzle and then screw it all of the way in. This may even push some material out of the heat block. Now disassemble it and try again in the standard orientation.
If this does not work, the threads may be bunged up. Next option is to "chase" the threads with a tap of the proper size. This appears to be an M6 thread (at least on the nozzle I tested). Try threading a M6 nut onto both nozzles to see if the threads are OK. If it binds, then chasing these threads on the nozzle with a M6 die may be required. To chase the threads in the heat block I would again do this from the back side to enhance the likelihood of getting the tap started straight and run it through. If the nut fits and the tap goes through, now try inserting the nozzle again into the heat block (hanging free). If that works, then try assembling it in the proper orientation up into the nextruder with the thumbscrews very loose. .