Hi. I have a problem in printing bigger objects. When the footprint of the object is larger than a square of 7cm the PLA looses grip on the heating bed and buckles upwards. And so the printer nozzle moves the object around. The bed temperature is between 50 and 60°C. What can I do to make bigger objects sticking to heating bed?
Can I heat up the bed up to 70 - 75°C?
Here are some pictures from my object:
plus.google.com/photos/10858602 … 3905314113
hi, you can use blue tape to fix the print on the bed
Hi,
the use of a mirror on the heatbed will solve your problem.
please search the forum for additional information.
Kind regards,
BigDee
PLA will not stick to a mirror, but using a mirror is a good idea to make it perfectly flat. Then as mentioned above, apply some blue painters tape and make sure the spacing of extruder is 0.25mm above the bed. With that, 50C will be plenty for very good adhesion. Even at room temperature it sticks well enough that I usually have to replace my tape since my prints stick to it better than the tape to the glass surface 
Actually PLA sticks very well to the mirror but it must be perfectly clean. the slightest veil of grease and it won’t stick.
Of course with blue tape it sticks even better.
Hi,
I agree with raby, a mirror heated to 50 °C works quite well. Just don’t touch the print area with your fingers or anything else that could add a film of grease to the surface. Actually, at some point the prints leave some kind of residue on the surface, like a coating, but barely visible, which increases adhesion even more.
Cheers,
kuraasu
I stand corrected then. When I added a 3mm glass plate to my heatbed (which I assume is no different than a mirror), I had virtually no adhesion with PLA. I tried roughing the surface a little, but that didnt help much either. So I went for blue painter tape and have not had issues since.
Hi,
one of the first modifications i tried was placing a mirror on the heatbed. I never even tried to print directly on the heatbed.
You have to make sure to wipe of all fingerprints. No need for any solvents or whatever, just a clean piece of cloth does a perfect job.
Raising the temperature of the heatbed to 60°C even improves the ‘stickyness’, but you will have to wait a bit longer before starting to print.
When finished, just wait for the heatbed to cool down to room temperature and your print will ‘pop off’ the bed. No force needed.
Succes,
BigDee
I just had some trouble with the filament always coming off the reflecting side of the mirror, so I tried turning it around and printing on the coated backside. This works pretty well, cleaning doesn’t seem to be such a big issue as on the mirror side and I didn’t have any liftoff issues since then anymore.
Additionally, it seems like turning the mirror frontside-down helped in decreasing heat-up time. I didn’t measure the time, but is really seems like putting the reflecting coating “behind” the class (from the heat bed PCB’s point of view) and printing on it’s back side helps in reaching the temperature more quickly.
small advice to you all.
hi , i had the same problems ,bended corners and so on , but not always … it was weird for me … i did try the blue tape and so on and play with printing settings … but that went even worse … i did the bed set up perfectly and temperature of the nozzle and bed was working properly ,so i realized that there is no problem with the printer ,but with the material.
Then i simply used the method which i learnt in the company i used to work . We were also producing plastic mouldings.
The problem here is not the bed ,if you did set up it properly , the problem here is the moisture in the material and getting higher % over time. I live close to the sea in the Uk ,here is a always big moisture in the air no matter how hot is. The material is simply too “wet” what is the cause of majority of printing issues . Water boils at 80 -100 degrees ,so you can imagine what is happening inside the nozzle ,if we use 190 degrees. Amount of steam is extruded with material causing bad printing issues ,bubbles , splashes ,pulling whiskies from nozzle etc and most of all the sticking in to bed .
I recommend for all of you who has problem with sticking into bed ,or any material issues . First before
you will start printing ,blow the material with hot air (not too hot! - don’t melt it down) simply use some electric fan and from reasonable distance keep blowing warm air about 40min.-2 hours to dry it. Then move the extruder up and keep extruding manually for a while the old material out of nozzle , check if around the tip of nozzle is properly cleaned as well. The nozzle has
“golden” colour ,so if you see there some burned black spots around the tip ,it must be cleaned.
When you stop printing put the material back into bag with couple of bags with silica gel - then next time should be enough to blow it for 20 - 40 minutes. Of course the drying time can be variable, all depends what area you live, room temperature etc… Since i started use this procedure i had not one issue with sticking on the original bed from welleman and printed products are very nice and also colour is much better ,no bubbles ,no empty spaces ,no whiskies pulling from the nozzle after retraction - simply the extruding the material from the nozzle is just perfect after proper drying with using standard printing settings. If you have moisture analyser, something like this(able.co.uk/MAX1000.htm) ,you can try measure it ,the allowance of moisture we used was
0.02 - 0.10% standard, any higher % can be the cause of the printing problems .
Sry for english , its still not good, but i hope you understand ,and i hope that this can help you to solve some problems with printing.
Get a piece of single pane glass, the thinnest sold at a hardware store in the US, and have them cut it to the size of the bed. I think it is 3/32". Go to a craft store like Hobby Lobby or Michael’s and buy a bottle of glass etching solution. Follow the etching solution directions and etch on side of your glass. If you have a diamond file, file the edges to remove sharp edges. Use 4 small binder clips to hold the glass to the bed. Wipe the glass with alcohol between prints to remove finger prints.
It roughens the surface enough for PLA to stick really well while leaving a smooth appearance on the print. No need for painters tape, hair spray, etc.
Glass and etching solution: Less than $15
I have not had a single print lift/curl since setting this up.
One other thing you might want to check is the fan. If one side is lifting and it is the side closest to the fan, you may have an issue with that side cooling too fast.
Hi all,
I recently had issues with the material not sticking, and upgraded the heat bed with a glass mirror from Ikea and the blue painters tape (as recommended in these forums).
The issue I have is the material not sticking sufficiently, causing the material to prefer to ‘curl’ up on itself and getting stuck to the nozzle and accumulating. Is this issue due to the nozzle or the bed?
I recently bought some new PLA filament from 3dfilaprint.com. When using the manual controls to extrude, i notice the material is rather slow to extrude which is causing it to again curl up. Are there settings I could try to force the material faster through the nozzle? Should i try printing closer/further away from the bed? Different temperatures to the default 190C and 50C?
Please can you suggest potential solutions to my problem.
Many thanks,
tiubacker
You sure it’s PLA you got and not ABS?
Yep, definitely PLA.
I should mention that before inserting the new filament, I needed to take off the hot-end and pull out the original filament since it was stuck inside the teflon part (as recommended in these forums). Could a blockage exist somewhere inside still (only blue filament is coming out now though)?
When the nozzle is heating up, is it normal for the filament to seep through? and where in Slic3r can i change the extrusion rate of the nozzle (that seems to be my main issue)?
Thanks again,
tiubacker