Warping Issues... Please throw your ideas at me...

[rlrcstr 1]

I'm printing a bit that's about 15cm long, 1.2cm wide and anywhere from .5cm to 1cm tall... I've got the bed at 80c and I'm still getting some warping on the ends on the piece. Should I go hotter on the bed? (This is PLA.)

Is there anything else I can do to help it? Will a brim or raft help?

Thanks.

J

[macua85 52]

With PLA you really shouldn't get warping issues, especially with a heated bed. The cause of this would usually be either a greasy/mucky bed, so wipe down with some alcohol to sort it. Or, bed levelling not quite right. If the nozzle is too far from the bed, the first layer doesn't get nicely 'squished' into the glass.

If you are still having problems after trying the above, use a glue stick on the bed and then try printing again. Similarly, a brim would help, but I wouldn't have thought it would be necessary with PLA. One more thing, if the model has square edges, it is more likely to lift, so try and round any edges using a filet feature of similar in the 3d modelling phase (doesn't have to be much ~1mm).

[jens 9]

Additionally, you could try to go down with your temperatures. For me, heating the bed to no more than 60 °C did help, as did minimising nozzle temp (you have to find the minimum for your material where layer bonding is still sufficient). Also, I usually never go above 40...50 % with the cooling fans for parts of that size.

[neotko 1,417]

I got warp on pla on some brands but it use to be (for me at least):

- Previus finalament left some traces that even the window cleaner didn't removed. Solved with some scratch/hot water cleanning + window cleaner before printing.

- It warps a bit because the temperature. Sometimes not just the bed but the filament temperature. Try raising the first layer temp.

[rooiejoris 5]

sometimes it helps that when first layer is a bit cloder to the bed

or push the bed a little bit up with your finger to make it stick better, i normally do that in the corners where the warping starts. When the first layer is perfect, warping shouldn't happen with pla

cheers \ joris

[rlrcstr 1]

I had tried bed temps of 50 to 80...  Looks like a bed temp of 60-ish and a hotter nozzle temp and 50% fan is eliminating the warping, but then I get quite a bit of stringing.  I've tried adjusting the retraction, but nothing seems to help that.

It's quite frustrating.  You see people posting these perfect looking prints, but I can't get close.

Edited August 17, 2015 by Guest

[gr5 2,172]

150mm is more difficult - the upper layers are cooling and pulling hard and that lifts the corners of the bottom layers. But this is solved. You probably just need to add brim but here's my full answer...

=========================================

lifting corners, curling corners, part sticking to glass

1) Make sure the glass is clean if you haven't cleaned it for a few weeks. You want a very thin coat of PVA glue which is found in hairspray, glue stick, wood glue. If you use glue stick or wood glue you need to dilute it with water - about 5 to 10 parts water to 1 part glue. So for example if you use glue stick, apply only to the outer edge of your model then add a tablespoon of water and spread with a tissue such that you thin it so much you can't see it anymore. wood glue is better. hairspray doesn't need to be diluted. When it dries it should be invisible. This glue works well for most plastics.

2) Heat the bed. This helps the plastic fill in completely (no air pockets) so you have better contact with the glass. For PLA any temp above 40C is safe. I often print at 60C bed.

3) heat the bed (didn't I already say that?). Keeping the bottom layers above the glass temp of the material makes it so the bottom layers can flex a bit (very very tiny amount) and relieve the tension/stress. For PLA 60C is better than 50C. 70C is even better but then you get other "warping" like issues at the corners where they move inward but if you are desperate it's worth it. For ABS you want 110C (100C is good enough).

4) rounded corners - having square corners puts all the lifting force on a tiny spot. Rounding the corner spreads the force out more. This is optional if you use brim.

5) Brim - this is the most important of all. Turn on the brim feature in cura and do 10 passes of brim. This is awesome.

6) Squish - make sure the bottom layer is squishing onto the glass with no gaps in the brim. The first trace going down should be flat like a pancake, not rounded like string. don't run the leveling procedure if it is off, just turn the 3 screws the same amount while it is printing the skirt or brim. Counter clockwise from below gets the bed closer to the nozzle. Don't panic, take a breath, think about which way to move the glass, think about how the screw works, then twist. This may take 30 seconds but it's worth it to not rush it. You can always restart the print.

If you do all this you will then ask me "how the hell do I get my part off the glass?". Well first let it cool completely. Or even put it in the freezer. Then use a sharp putty knife under a corner and it should pop off.