Blobbing on the print
After some work, I finally got Benchy to print really nicely and with everything in line. I went ahead and printed a floor piece for D+D, one I had printed sort of successfully before, and it came out with heavy blobs on the print itself (not the extruder like normally a blob would be) and a ton of stringing. The base was solid flat, and this was all done on the top and towards the end of the print I believe, so I figured that maybe it was just a mistake as the previous prints of this same model did not do this (just were not perfect due to lose belts). The second print did exactly the same again, so now I am not really sure what is going on. Any thoughts? The print seems to stick to the bed, the nozzle is clean, so thinking it isn't that the model shifts early on (I check for about 20 minutes after the start and before bed, printing nicely at that point).
The first print is to the right, and doesn't show all the strings that were on the print and all over the print bed. The second print is on the left, less strings but still long ones and the blob....
RE: Blobbing on the print
I haven't seen anything quite like this before. Were the parts firmly attached to the sheet when you found them this way? By firmly, I mean did they require removing the sheet, flexing it so the parts would come free (if you didn't have to flex the sheet them they were not firmly attached like they should have been).
RE: Blobbing on the print
Second question: run a self test. Report back the Belt Tension numbers from the LCD menus -- but do not adjust anything! Just report the numbers - they are useful for diagnosis.
RE: Blobbing on the print
No, not firmly I suppose. They were definitely attached to the sheet but did not require it to be bent, just pulled with a bit of force off.
X: 254
Y: 270
The Y is a little looser than when I tightened it two prints ago (was 265), so might be a portion of the issue.
RE: Blobbing on the print
254 is quite low; indicative of bearings not rolling smoothly. You probably should loosen the screws on the back of the extruder and U-bolts underside of the heat bed to ensure they aren't causing binding; the nuts on the U-bolts should be snug, not tight. And if that doesn't help then try a few drops of machine oil on the rods, working the extruder back and forth to get oil inside the bearings (and the same for both X and Y axis).
My guess is the printer seized up, and both axes were not moving, leaving the extruder to simply pour filament out in small areas.
If it isn't that, then the second guess is the extruder is leaking due to an improperly installed nozzle. A quick look at the heater block can remove this from the list.
RE: Blobbing on the print
I doubt that its the tension, but I can check to make sure the screws aren't too tight. The X was at 280+ when I first started, so I tightened it to get it closer to what I was researching and finding was the 'golden' range of 250-270 for the two. Had a lot of shifts before, which made things very ugly, but got a solid print of the boat with this, one time. Haven't tried again, just the floor.
Going to grease the rods as well, see if maybe that fixes it. Don't think the nozzle is lose, I have gone through many, many prints to get this right and only the last two have done this blob, so I think maybe it needing grease might be the most likely. Will try and get back with the update!
RE: Blobbing on the print
Again - the belt tension numbers are not at all meaningful for belt tension. You will break your printer if you try to adjust belt tension to that imaginary 240 number in the manual.
The golden number for "belt tension" is 300. And 300 means the axis moves freely, and minimizes friction related crashes - just like the ones you are having.
If you have changed nozzle, a gap between the nozzle and heat break is a serious possibility. Did you follow the E3D-V6 assembly procedure? If not, you should go back, tear the hot end apart and put it back together - but follow it this time. People who don't follow the E3D-V6 assembly instructions invariably have leaks.