Printing ABS

I am trying to print ABS and so far have had mixed success. My first attempt was spending one week-end trying to print some red spool marked PLA which actually was ABS!
What I managed to print in this first attempt was a bottle opener (Bottle opener, works nicely with a 10 euro-cent coin!) and a drill bit (M4 Drill bit ABS printed with Foldarap..) Other attempts suffered part not sticking to bed or delamination.
Later I managed to print other cylindrical parts, namely a Saturn V moon rocket.
I spent the whole day trying to print the z-top_left.stl with no success: the part always gets off of the heated bed, even though I went up to 80°C and cleaned the bed every time with acetone. One time, I nearly succeeded: I used hair spray on the bed and the part stuck, but when I removed it, I got delamination (layers getting apart).
Last week I managed to print an x-carriage.stl.
I have two hypotheses for print failure:
Only 'compact' objects can be printed (no thin flat surface outside)
Only small objects can be printed (at the center of the bed, where temperature is higher)
To test the temperature hypothesis, I will have to test a new heating resistor configuration, more on this later.

Well, now printing my z-top_left.stl with PLA...

Generally speaking, if your bed is well leveled anything that is non-symetrical will tend to warp more, as the forces gather more in some spots than others.

Also the larger the horizontal the part is, the bigger the accumulated warping forces become (I even have seen some delamination of the parts mid-height during print when the parts adhered very well to the bed).


Might want to try adding a "brim" if you haven't tried yet, helps with bed adhesion.


Regarding bed temperature, anything under 100°C won't help much for ABS. I even seen some ABS filaments needing 115°C.

ATTENTION I'm not sure the peltier heating element on a foldarap can stand that temperature, I don't have one myself.

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Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.

Hi DeuxVis.

After browsing the web, I found a few information about delamination. One of them was the advice to have slices no more than 60% of you nozzle diameter. Until now I always thought 80% was fine (and for PLA and on my Mendel with 110ºC heated bed it has been so far). Until now I had been working with 0,2mm heights, with my Reprappro 0,3 mm nozzle - BAD. So I changed my slicing height to 0,15mm.
Conversely, I found that delamination can also come from too fast cooling, so I disassembled my passive cooling 'guide' (switched off the minimum fan speed in Slic3r a while ago, as nicely explained in the instructions).
Now my current configuration is 80ºC heated bed (well, my IR thermometer tells me 72ºC to 77º in the corners of the heated bed) with hair spray (no need to respray for each print, I don't know yet how many prints you can make before having to prepare the bed again - though the stuff mightily stinks when you heat it the first time, on following prints you don't smell it anymore, although your parts have a whiff...) and 6mm brim (yes I have been working on this one for quite some time now: it is a lot, but seems to work pretty good). So with this I printed the z-top_left.stl successfully, with just two small slits (I won't call them cracks, although I have no doubt the part will break if I use it as is). Hopefully a friend of mine should be able to make pictures with his professional gear next week and I'll show the difference. Also, I will do some acetone-vapor curing and am curious to see the result (hopefully with pictures as well).
Right now I am printing a big cogwheel with V-shaped teeth, layer 61/93, so far so good.
For the point about strain not being the same everywhere: A+, this explains quite a lot. This is why some parts print better than others.

PS.: Peltier will definitely NOT work at so high a temperature, their internal temperature will be much higher and the inner solder will melt, destroying the Peltier. Right now I am working with 3 cemented 4R7 resistors. I just received my four TO220 7R5, I will have to test this by fitting them into the corners. Should be done next week as well, maybe with a new heated bed isolation DXF.

Signing off.

Personally I never use ABS, I tried once without much success (but blue tape + heated bed seems to works at slightly lower temp than kapton), and only know of one person who did it but ended with mixed pla/abs and clogged his nozzle ^^'