I a printing a part with PLA. I do not print lots with PLA. I noticed the part pulling away from the bed near the aux fan output. Actually, I just noticed that it is pulling away in an area far away from the fan as well.
Should I shut off the Aux fan when printing PLA?
PS… I did not use a brim
The aux fan is primarily there to help with PLA, but it can cause problems with objects too close to it. Given that you had curling away from the fan, I would not blame the fan. Clean the bed plate with dish soap and warm water, dry thoroughly, and raise the bed temp 5-10 degrees. You should use a brim if the contact area is small.
Thanks Steve. Very much appreciated. I have very little experience with PLA. I Mostly print PETG and have never had anything pull away from the bed. The contact area is quite large so I did not use a brim. I will surely clean the bed and raise the temperature. I did not even think of raising the bed temp as I am using Bambu PLA Basic with their suggested temperature.
Thanks again… Richard
I look at it differently, as far as when to use a brim. I definitely use them on small surface areas, but I also swear by them on large flat ones too. The problem you are trying to avoid in this case, warping off the bed, is caused by the way plastic changes temperature at different rates during printing. Things to look out for is how thick the bottom layer is. The more plastic (high infill or wall count), the more forces will be applied when the plastic begins cooling during the print (generally the plastic on the bed is still warm while the plastic just above is cooling fast and pulling up the lower layers from the bed).
So knowing that, the quick answer it to lessen the infill or wall count around the edges. But that isn’t always possible, so a quick Band Aid that sometimes helps is a brim. The brim is good because it allows you to reinforce the edge with more surface area to hold the print down without adding thickness (and thus more pulling up force). So, I tend to use brims whenever I have a large flat surface. It seems counter productive at first, but the results seem to be worth it. Note, it doesn’t guarantee success, but it is additional warp insurance.
Thanks… I think you are spot on. This model is big and tall, and I intentionally added an extra perimeter wall to give it additional strength. I noticed that the PLA sticks well to the textured PEI sheet, but not as well as the PETG. Sometimes the PETG is actually hard to get off the plate. This was the first time I printed something big with PLA and added the additional perimeter wall. I usually avoid brims because they are harder to remove with PETG than PLA. I feel fairly certain that if I added the brim it most likely would not have pulled off the bed.
Thanks for your thoughts… Richard
Not to muddy the water but originally had a P1P without the AUX fan, most people who comment to talk about needing it vs not needing it don’t have or never had a P1P. I have completed literally hundreds of prints on the P1P and never had a aux fan and all completed successfully. ALL prints completed successfully.
Now not saying you’d never need it on PLA but I have yet to find a model where I saw it going to add a benefit. Just make sure you wash that build plate with hot soap and water then make sure when selecting the textured build plate it’s setting the temp to 65c.
Thanks. I converted my P1P to the P1S and also had the same thought as you. I question if the fan is really needed. Since this part pulled of the plate on both the side with the fan and without, and the part is big enough to fully block the air flow from the fan… I don’t think the fan was the culprit in this case, but I think I could easily just shut the fan off.
Thanks… Richard.
You’re welcome, I too have since converted mine to the P1S and after a couple larger prints failed at the AUX fan side where they were warping I just stopped printing with the AUX fan on with PLA and now take the top off and open the door like the WIkI recommends and have gone back to PLA success! lol
I disagree. Most of the time the aux fan is not useful for PLA and for prints that have a large base it usually causes the edge to lift an ruin the print.
My filament profiles for PLA always have the aux fan off. The only time I use it is for prints with overhangs and bridges when I have tuned the the speeds to get the model printed quickly.
Good morning.
This discussion is quite interesting as i printed most things with PLA in the past and a lot of things since last Friday when I got the BBL P1S.
First infused the standard BBl PLA settings for the green and orange filaments that came with the printer. All prints fine, aux fan on as set by the BBL settings. Also, door and top closed. Prints fine.
After drying my PETG in the oven, I was able to print successfully with the general petg profile. With brim and without.
I am now printing BambuLab spools with honeycomb pattern with a profile from then gyroid Bambu lab spool using the ecoPLA white from 3D Jake. As it is a large part, lot of surface area, the aux fan is turned off.
Don’t know it the aux fan would make a difference, we will see. For the train whistles, small surface contact I used a brim and aux fan was turned on. No problems as all.
These are just my thoughts. Filaments are different. But for now I can say that the textured pei plate is mega super strong.
Quick question, did the AUX fan not turn on when you removed the Lid and kept the door open? if so the AUX is of course to blame.