UM2 warping with Ultimaker PLA

[si2w 8]

Hi,

 

I received my UM2 last week. My first print (um robot) was just perfect.

 

After this good experience, I tried to print a spool for laywood : http://www.thingiverse.com/thing:39564. I added some glue on the glass. It was a *big* failure.

 

I tried to redo the levelling and it failed also.

 

I noticed that the glue was dried and doesn't stick anymore.

I cleaned the glass and put a thin layer of glue.

 

The first 5 layers were almost good. The border of the spool's hub began to move up. It finished by colliding with the hot end...

 

How can I avoid these kind of problem ?

How can I change the heated bed temperature ?

When use tape or glue ?

 

Thanks !

 

Youtube link :

 

 

[IRobertI 520]

For the glue, put on a thin coat. If you get lumps you can use a damp cloth/sponge to dissolve and spread the glue out better. It will dry as the bed heats up.

What failed with the bed leveling?

I've left glue on the glass for days of printing without issue. Even if it feels dry it still works, try pressing your finger against the glue for a little while to heat and moist it a bit and you'll feel that it is still tacky.

It's difficult to see on the video but it looks to me like the print is starting a bit too far from the bed so that it's not sticking very well. In the last step of the bed leveling procedure you should feel a slight drag on the paper as you slide it between the nozzle and the bed.

Use glue if you need extra sticking power (I often print on a completely clean glass). Use tape if you're printing without heating up your bed.

edit: Forgot about the bed temperature setting. It's under the material settings.

 

[si2w 8]

The bed leveling is a little tricky the first time. I wanted to be sure that it was well configured.

 

When the glue was dried, I tried to add a second layer on top. The PLA was not sticking on the bed and I had to stop the mess...

 

It was solved by cleaning the glass completely and put a new layer of glue.

 

Is there some PLA colors who are more subject to warping ? I have pink, yellow, green, white, natural.

 

Thanks for advices !

 

For the glue, put on a thin coat. If you get lumps you can use a damp cloth/sponge to dissolve and spread the glue out better. It will dry as the bed heats up.

What failed with the bed leveling?

I've left glue on the glass for days of printing without issue. Even if it feels dry it still works, try pressing your finger against the glue for a little while to heat and moist it a bit and you'll feel that it is still tacky.

It's difficult to see on the video but it looks to me like the print is starting a bit too far from the bed so that it's not sticking very well. In the last step of the bed leveling procedure you should feel a slight drag on the paper as you slide it between the nozzle and the bed.

Use glue if you need extra sticking power (I often print on a completely clean glass). Use tape if you're printing without heating up your bed.

edit: Forgot about the bed temperature setting. It's under the material settings.

 

[gr5 2,172]

This is minor warping. You can fix it by using 70C bed temp, using brim (you didn't use brim - use brim - it works great) and of course the glue stick.

The brim keeps air from getting under the corner of your print - it is important. Once the print starts lifting it is hard to stop. Brim helps this quite a bit.

PLA has a melting temperature and a glass temperature. The melting temperature is around 170C. The glass temperature is around 50-60C. When PLA gets above the glass temperature it still holds it's shape but if you push on it, then it will very slowly change shape. Permanently. Keeping the bottom few layers above the glass temperature mean it won't warp and if layers higher up warp it will instead deform a bit but it won't lift off the glass.

As for PLAs that don't warp so much:

PLA45 (google it). Unfortunately PLA45 only comes in black and white I believe.

Also ABS warps much *more* than PLA.

 

[dkaygee 0]

I found that adding a Brim in Cura works well for PLA to stick. I've quit using the gluestick for PLA, all it was doing was clogging up the nozzle. I still use it for ABS however. I found I had to up my PLA temp as well to compensate for the colder temps in my work area. 10 degrees did it for me. I would suggest focusing on your bed level if the PLA will not stick.

 

[illuminarti 18]

Good feedback, dkaygee, but there's no reason for gluestick to ever clog the nozzle of your printer. Indeed, there's no reason for gluestick to get anywhere near the nozzle of your printer - well not closer than a few tenths of a mm :-)

When you add glue to the bed, wipe the bed well with a wet paper towel or sponge. That will dissolve all of the glue into the added water, and totally remove any lumps. Then, as the bed heats up, the water will quickly dry, leaving a very thin layer of glue well sealed to the glass bed. It works great for printing, gives good adhesion, leaves the bottom of your prints mirror smooth, and there's no danger of it ever getting onto your nozzle.