bed level changing

Hi,

Is it normal for bed level to change a bit after a print?
I find that it there is different tension when pulling a piece of paper from under the nozzle before and after use…

Typically, once you set the initial homing height, it’s pretty spot on. The first and second layer of printing will take care of any unevenness due to the ABS & acetone solution or other bed treatments. It’s rather forgiving.

The thing is, I am trying to exclude one thing at a time for my current problem. That is, ABS not sticking.
I never realized that it could be a problem for this material. My TAZ 3.1 came with heated bed and PET over it, so I thought that “not sticking to bed” shouldn’t be a problem
I am leveling the bed all the time, changing parameters etc. but still …
Even got a micrometer to measure the filament diameter (and it seems consistent enough)
… Also, I loaded some configs from Lulzbot library for ABS, and even deleted M104 and M140 from Gcode, to keep the temperature consistent.
Getting a bit paranoid, so I could try to encase the whole thing against the drafts, I suppose… :smiley:

could I get any leads on the thought process? Where should I start to solve it from…

thanks

After installing a new sheet of PET, I generally have to apply 4 or 5 good coats of ABS juice to the bed before I get satisfactory adhesion.

About that… I read that there is no point in trying to put several layers of the liquid, because you will always get just one layer. That as in the next sweep removes previous layer…

Is there any chance to put that ABS mixture directly to glass?

You can use the ABS solution on bare glass if you like. Some users are transitioning to use PVA glue sticks or PVA solution (watered down white school glue/school glue sticks/purple glue sticks). Apply it to the bed and print. If the part sticks too well, since PVA is water soluble, you can use a little to help free the part.

That hasn’t been the case on my printer. I re-saturate the paper towel between coats and lightly wipe each coat on with light pressure. It has really helped me when I switch to a new sheet of PET.

So its always better to have some solution applied over PET…?
When I got my TAZ3 and set it up, I immediatelly tried to print the octopus with the little sample material and fine ABS CONFIG from lulzbot… It came out so great, even a lot better than the octopus that came as a sample print with the package.
Thats why I am trying to find out why can’t I repeat the result now that I know a lot more about the printing…

Thank you guys for the help

I only print in ABS. I find that it just will not stick if the ABS solution is absent.

TRESemme extra hold #4 hairspray works to hold models to the plate while printing for me, in PLA that is. Clean up is easy with simple Green water solution. I will warn you if you use hairspray, you have to clean and re-lube the rails, WD40 seems to work for the lube, I apply it with toilet paper which has been sprayed with it after removing the hairspray vapor overspray from the rails. I recently stated using a vapor barrier fence/mask (piece of cardboard) when applying the hairspray, it prevents the majority of the hairspray from landing on the rails.

I wonder why there is such a variance to the bed level height between prints? This is an issue that should be addressed in future TAZ models. I totally recommend using the calibration tools provided to reset height before starting a print, the squish height must be set at the right height or you risk losing the model during the print.

I’m attaching the calibration ring print I use to adjust the bed height- (before I make a big print), if you printed the whole calibration ring it would use 800+ mm of filament, I suggest just letting it print until you have the bed height adjusted so that you can see the extrusion squish is the same across the bed, after it reaches this point, simply stop the print from the TAZ 4 Console. I load all my prints to the TAZ SD card so that I can print without my computer having to be on.

The G-code calibration file is for active calibration (during print) this can lead to problems/collisions if you aren’t agile enough to adjust your Allen screw heads while the printer is in motion. Eventually I would suggest that sprockets are installed on or in place of the Allen heads so that the calibration can be made without the long Allen wrench having to be stuck in the screw while the printer is in motion. I cannot see a way currently to calibrate the bed without adjusting the bed screws while printing.

Ogrethetoymaker
Base setup calibration ring.gcode (513 KB)

Some users have encountered flaking or delamination when removing parts when printing on bare glass. We recommend printing with either the stock PET surface, or with the new PEI print surface that some of our more advanced users are using with great success.

Thanks!

interestingly after installing my E3Dv6 I only have to adjust my table height about once a week vs every print, fyi.

What do you mean? Your Hotend makes it less prone to decalibration?