SoliForum - 3D Printing Community — extruded ABS filament is too brittle

Re: extruded ABS filament is too brittle

null@example.com (richh001) — Sun, 01 Mar 2015 23:17:38 +0000

I used the pound of MG plastic with my filastruder two days ago, and it came out great, I am use to the cheap Chinese stuff, as the spools are better than the plastic on them.
I also put the thermocouple between the heating element and coupling, as the fan was causing too much temperature drop at the nozzle, and I wanted to switch it out with a filtered nozzle after run in.
I extruded at 200C, 3mm filament.

The plastic I got with my filastruder came in a ziploc bag with a hole in it, and half of the plastic was in the bottom of the box, and it worked great, without drying.....although, it is pretty dry outside from this excessive Global Warming that we are having....

Re: extruded ABS filament is too brittle

null@example.com (titaniadioxide) — Sun, 01 Mar 2015 21:55:15 +0000

Another question - are you using masterbatch? I had this problem a lot when I was using masterbatch. It turns out I was using way too much, and that made it really brittle, and too thin.

Re: extruded ABS filament is too brittle

null@example.com (RISI) — Sat, 07 Feb 2015 10:43:43 +0000

We have used wet pellets before without problems (we washed them)
So I'm not certain what the impact moisture has?
But what we did notice about bubbling is that MG94 produces Gas somewhere above 200°C so bubbles form inside from the gas itself (even desert dried pelllets produce gas bubbles) which then twists and merges into the structure as it's extruded creating a weak filament with air pockets.

Last year, the temperature sensor was dislodged so our filament was heating up to 250 degrees C causing them to be very brittle with lots of evaporated plastic air pockets, We solved this by wedging the sensor onto the heater itself, instead of the notch at the nipple/nozzle

We also pre-heat the nozzles and letting it sit for around 5 minutes at 200 degrees C to let all the air escape and the filament melt properly then the filament that came out was nice and smooth, at least for a while...

after that it depends on extrusion temperature. Mentioned somethere else on this forum. 235 deg C on MG94 pellets creates rough filament, but smooth with PA747 pellets.. so it depends on your pellets. I personally prefer PA747 over MG94 at the moment due to high temperature extrusion ability.
hope it helps

Re: extruded ABS filament is too brittle

null@example.com (elmoret) — Tue, 03 Feb 2015 14:41:38 +0000

Excessive moisture. You may need to dry the pellets before use. That is what industrial extruders do.

What's your serial number?

extruded ABS filament is too brittle

null@example.com (redbarret) — Tue, 03 Feb 2015 12:14:57 +0000

Compared to my Solidoodle filament, the fiament produced by my Filastruder with the pellets that came with it are very brittle. Try to bend them just a bit and it snaps into two pieces. What usually causes this?