ABS curling, warping and not sticking to bed UMO

[carinac 0]

Hi all,

I tried to print a push button in ABS in very many ways. I tried a bigger plane, skirt, brim, mouse ears, raft, even pritt-stick on the bed etc. But nothing helps from warping, curling and coming off the bed.

I know that it will probably go better with a heated bed, but I don't have it (yet), so that doesn't help me. I made some pictures, you can see in the attached album.

My settings are at the last picture of the model and settings in cura:

layer height 0.25

shell 0.8

top/bottom 0.6

fill 10%

speed 80

temp 230

rotate 30 degree (then no overlap, but it falls down with no support)

support touching buildplate

expert fix type A is allways on

Can anyone advise me how to print this on a UM Original?

Thanks a lot in advance!

 

[gr5 2,265]

There's lots of tricks. Since you have no heated bed you might have to go old school: raft.

When you used the blue tape did the tape lift off the bed? If so use wider tape. Also did you clean the blue tape with isopropyl alcohol? Found at any store that sells bandages. Wiping with alcohol cleans the wax off the tape.

Also when you print is the bottom layer squished nicely into the cracks of the blue tape? You want the first layer squished flat like a pancake.

Anyway, consider using the "raft" feature. This is how old reprap printers were able to print ABS without a heated bed. The raft absorbs just enough of the warp (just a tiny tiny bit) such that the part doesn't come off the bed. It warps but such a tiny tiny amount that you can't see it visually.

Aheated chamber helps (enclose the 3 sides with clear plastic wrap and put a box on top - then put a hair dryer in there for 10 minutes, then turn off the hair dryer and start printing). The glass temp of ABS is about 100C and room temperature is about 20C. You get about .6% shrinkage in that range and that causes all the problems. If you can heat the air half way (60C) then you get half the shrinking (about the same as PLA which cools from 60C to 20C and does about .3% shrinkage).

 

[carinac 0]

Haha, I like the heated chamber :cool: I'll try that. I live in the Netherlands and it is very cold here (5-7 degrees), but nevertheless I printed with window open as ABS is not a very healthy air. So it was freezing in the chamber, this might be the solution, thanks a lot.

If not I'll try the isopropyl alcohol, although this isn't available in the Netherlands, unfortunately, but I'll buy it by the internet. As you did advise me that before and I didn't do it...

The raft I tried but the tape comes off anyway. Wider tape will probably not prevent that, as it really comes high up (about 4 mm), very clear visible.

Thanks!

 

 

[gr5 2,265]

It doesn't have to be isopropyl alcohol - you can use other strong cleaners. Maybe paint thinner or maybe acetone. I'm not really sure what else works. I have been to the Netherlands and find it very difficult to believe you don't have this product in your drug stores - maybe it has another name? In most countries it is found with the bandages:

 

[gr5 2,265]

Wider tape helps quite a bit if the tape is lifting off. If the tape is twice as wide it has twice the holding force. Usually most of the initial lifting force is concentrated on a vary small area at the corner - spreading that over wider tape helps. Illuminarti has 150mm wide tape. I use 50mm wide tape.

I haven't used Cura raft but I've seen what it creates and I don't think it's designed properly to relieve the lifting forces. Daid is living in the "age of PLA". If you go back a few years all the slicers were designed to work with ABS. If you try this older version of Cura where the slicing engine wasn't written by Daid and try it's raft feature I think you might get better results but I'm not sure:

Cura 13.04 was the last version with the older slicer (it's very slow! may take a few minutes to slice your part if it's big)

http://software.ultimaker.com/old/

I'd be very curious to hear if this older style raft works any better at preventing lifting. There are plenty of reprap printers out there that print ABS fine without heated bed. Many of them used cold smooth materials (like glass or kapton tape) combined with PVA glue (very thin layer - usually from hairspray) and raft.