ABS delaminating

[mikilu 0]

When printing in ABS I encounter the following error

The ABS is delaminating,

I have a heatbed set at 100 degree and I am printing the ABS at 230 degrees.

Any tips would be very helpfull as I do want to make ABS my standard printing material. I have read something about Natural ABS but I'am not sure what that is.

Thanks

 

[simon 1]

Have you tried the default UM2 ABS settings.

Bed 90

Fan 50

Printer head 260

Flow rate 107%

Try print speed 30mm/s

I printed a tall thin ABS part today with those settings. I did have a bit of delamination, but nothing like that. I'm still working on settings but something around those values may work better.

[am001 0]

You can improve it a little with settings, particularly slow or switch off the fan, but the only real answer to this is a heated chamber.

Try wrapping your UM in bubble wrap or towels as a test, often this is enough just to retain some of the heat bed energy.

 

[owen 19]

When printing in ABS I encounter the following error

 

The ABS is delaminating,

I have a heatbed set at 100 degree and I am printing the ABS at 230 degrees.

Any tips would be very helpfull as I do want to make ABS my standard printing material. I have read something about Natural ABS but I'am not sure what that is.

Thanks

 

Hi Mikilu

More usual settings are 110C Bed and 245-250 Nozzle

 

[simon 1]

I've tried the bed at 110 but it did seem to cause horrible contraction issues in the bottom few layers. The first layer or two was ok but then, if printing a tube for example, the diameter would neck down, and then build back up again. No fan is ok as long as you have no bridging, but if you're extruding in thin air, for example filling in over sparse infill with a flat surface, a bit of fan is essential. A heated chamber in combination with getting your other settings right is probably the only way to do it really. I place mine in a metal cabinet . It's not sealed but it gets cosy in there. Above the heated platform it gets up to about 45C. Below it's about 25C. I've heard its important to make sure you don't cook you motors, but I've never heard of anyone actually doing it though.

I prefer ABS because of its mechanical properties, but it does contract more than PLA. One of its key properties is it's glass transition temperature, which is somewhere around 100C for Ultimaker ABS (not exactly sure as I haven't done enough tests yet). By default it extrudes in the amorphous condition. The plastic molecules are all jumbled, and they take up more space (volume internally). If you hold plastic at a temperature above its glass transition temperature for too long the structure tends towards crystalline. Crystalline plastic has a lower volume than amorphous which it was you get higher levels of contraction. This is why on injection moulded products you can sometimes see the position of ribs on the out side of a product casing. It hasn't cooled quickly enough and at the point where the rib meets the casing the volume of plastic is higher and takes a little longer to cool down. This allows the plastic to transition towards crystalline. They are called sink marks and designers and injection moulders try very hard to prevent them. It's one of the key limitiming factors when injection moulding plastic. Amorphous contraction is about 2-3% for many plastics, but can be as high as 7-9% for crystalline. Crystalline also makes the plastic more brittle. Hope that helps explain some of the factors that you need to take into consideration :-)