I have just installed the new hexagon hot end extruder assembly from Lulzbot on my Taz 4. Things have been going great until the last two days. I have been doing some prints only a couple hours long and about halfway through the extruder stops extruding!
I have investigated the issue and believe the two cap screws that hold the pressure on the filament when running through the teeth into the hot end are coming loose.
I have done a print with them completely tightened at the recommended 10mm distance and a couple hours into the print i checked the screws and they were completely loose!
Is anyone having this same issue? Hope I can figure out a solution soon.
I’d give that a shot, but I’m still trying to figure out how to get this ABS out of the feed tube, tried heating it up and giving it a push but that doesn’t seem to be working. sigh.
I have done a print with them completely tightened at the recommended 10mm distance and a couple hours into the print i checked the screws and they were completely loose!
Is anyone having this same issue? Hope I can figure out a solution soon.
I’ve had my hexagon installed for about a week now and I probably have 40+ hours of print time on it. I have not had this issue. I haven’t messed with the tension at all. The cap screws for my hexagon came from the factory tighter than the ones on my budaschnozzle did.
I have tried tightening them more but they seem to just get loose while printing. I have investigated the difference between the old budaschnozzle and the new hexagon assembly and I don’t see much.
And just to clarify I am talking about these two screws here.
Where you have them set is way tight and they should in no way back themselves out. Are you doing prints that create any harmonics? That’s about the only reason I can think of as to why they would still come loose.
Do you have access to a hammer and a center punch? What you could do is note where the threads engage the nuts and peen the threads a little bit so it acts kinda like a thread locker. Try and do it lightly at first because if you peen the threads too much then you won’t be able to turn the screws by hand anymore.
Here’s how less tight mine are and they haven’t moved at all, weird.
Thank you everyone for the suggestions, there certainly may be some vibration or harmonics happening here and I will certainly try a different print to see if the same thing happens.
Speaking of having the screws too tight, in the start up manual for the Taz4 they reference some distance 10mm from the caps. Where is this measuring from and too? its very non descript.
Peening the threads is a great idea and will certainly try this if it turn out it is not model dependent.
Thank you all for your help again. I will update this once I try these options!
Speaking of having the screws too tight, in the start up manual for the Taz4 they reference some distance 10mm from the caps. Where is this measuring from and too? its very non descript.
See where the springs are on the idler tension screws? The 10mm should be the length of spring plus both washers. This is just a starting point and the tension may need to be adjusted depending on the type of plastic you are printing with
Side question, is anyone printing with PLA and the new hexagon assembly? What is the Estep you are getting for your new calibration? I am getting something around 1150. Is someone getting close to this?
I did initially. After tightening up a bit on the idler It was brought down a bit, but I think I’m still somewhere in the high 900s. I can’t check right now since I’m not home, but I’ll try to remember to update this tonight. No promises… Seems pretty high considering my buda 2 was at 840…
I have been in conversations with Lulzbot support and we are working through the issues here, but I think ultimately it may be a balance between the correct tension and correct temp to get the calibration to work out here. But agreed high 900s does seem high compared to the previous version.
Ill try to update this is I learn anything more from lulz support.
I thought I was loosing my mind the first time that happened to me on my printer. Spent about a week trying everything I could think of, rebuilding the heated bed, reinventing the Z height adjuster to use a micrometer barrel, etc. I probably took that poor printer apart 3 times (it was my old AO-10x) before I noticed it was that stupid set screw on the small gear. A bit of Blue Loctite and there hasn’t been a repeat. I did learn a lot about calibrating and setting up a 3d printer that way though hehe.
