Black ABS from Aus difficult to use...whats with overhangs?

[smarterengineering]

Gday all,

Had the UP for a few weeks, have been happy so far until now when im starting to realise certain difficulties...

FIRST

I recently bought some Black ABS from the sellers down here in Aus/NZ.

After about 10 prints trying different bed temps (leaving it to preheat etc) different models and various settings ive come to the conclusion that using the black ABS with my machine you cant tell the raft apart from the part...

What i mean is

- the raft and first couple of layers before it starts the part basically are melted together that well that i cant seperate them...

I have to cut the raft off and chisel/sand the last few layers of raft from my pieces. It doesnt come apart as the White ABS did...(could this have anything to do with nozzel height?)

this has ruined various prints because the parts break when trying to remove these bottom layers. eg removing a 3 or 4 layer raft section before a part that is only a few mm thick...

Particularly when i paid 2x what it costs in the US

SECONDLY

I see other peoples prints where the over hangs are so nice, Even with a high level of support density and low space space my machine still does overhangs (eg the bottom of a sphere) horribly. Below i have an example of a basic doorstop i made...look at that difference in the spehere on the end top and bottom.

Im starting to get so frustrated, wish i had someone close by that could tell me whats going on ><

Also is anyone elses machine really noisy when moving back and forth? enough i can hear it at the other end of my house when its working.

Thanks


Pictures coming...have to resize them all

[smarterengineering]

cont

[JuliaDee]

The only black I've tried has been from Octave Systems. It has proven a bit more problematic than some other colors, but I have gotten some acceptable results with it, generally better than what is shown in your photos. Firstly, black simply tends to show imperfections more than other colors. Secondly, I think its (presumably) high pigment level leads more quickly to nozzle clogging than other colors. Thirdly, it seems to "dry" more quickly than other colors, which I think can lead to poor layer lamination. YMMV.

The support material you're having difficulty removing is not "raft" per se, it is "dense support". The Up! software puts it underneath all horizontal surfaces, and yes, it can be really difficult to remove. Using Drew Petitclerc's fan duct which directs some air to the nozzle may help. I'm sure the adhesion of the dense support is also related to the specific plastic you're using - other colors or vendors' material may be different. It is not related to the vertical height adjustment. The vertical height adjustment only affects the very first layer of the raft. After that, the platform just drops 0.2mm with each layer.

I haven't really experimented with bed temperature or attempted to correlate it with difficulty of dense support removal. I just hit "preheat bed" while setting up every print I do.

I wish the Up! software provided more options for dense support that might make it easier to remove. Obviously, using one of the "raftless" printing techniques will take care of the issue on the bottom of your parts, but it won't help for other horizontal surfaces you might have.

Finally, try different orientations of your part - I think the one that you show in the photos might come out better if you were to flip it over.

julia

[smarterengineering]

Thanks for the reply,

It was orientated that way to ensure the visible surface (its a car trim) would be the final surface.

Ill try a few other things, i guess the high levels of pigment may reduce the melting temperature and making it a bit weird to work with.

I have made my own fan duct that covers over the heat sink, blows from the top and has a nozzle selector at the bottom. Just about to try that

[wackojacko]

Try using the v7 wind barrier from their support pages under updates. That works well with the black filament from www.3dprintingsystems.com

[smarterengineering]

That also work with the white?

I have made my own with a switch to switch between cooling to blow the air away from the print.

I tried that this time and it seemed it was easier to peel away. HOWEVER

Whats the go with the horrible overhangs?? When im printing an overhang (regardless of speed) the overhang part starts to warp up on individual layers so the next layer/pass of the head runs into it and adds another layer.

Im printing a sphere at the moment to see hot it looks with and without the air blowing on it to get a comparison.

However for prints that require nice detail it kind of ruins it.

I printed the two interlocked cubes that you can find on thingiverse....damn they look horrible looks like someone went at it with a lighter and melted all the edges.


Any thoughts on this?? im hoping its just to do with the setup but i have no idea ><

[smarterengineering]

BAM faith in 3d printing restored.!!

After using the SmarterEngineering (mine) Wind Shroud i can make sweet parts that just peel away.

Will be posting this part soon.

[Madox]

Bilbys? :/

[smarterengineering]

The black i am using is from the supplier (and the place i bought the machine from) the usual for us in Aus/NZ


Actually had it jam last night, the wire wouldnt fit in i think cause i cleaned the nozzle that didnt help then i chopped a section off and it worked.

[wackojacko]

The new revised black and orange ABS filaments (in cardboard spools) are excellent from www.store.3dprintingsystems.com.au with new colours coming soon.

[JuliaDee]

The new revised black and orange ABS filaments (in cardboard spools) are excellent from http://www.store.3dprintingsystems.com.au with new colours coming soon.

I hate those cardboard spools... but better filament will be great.

[josejuako]

Hi , I use it . Whitout problems , very good material , the black color is difficult to find a good extrude work , not all black materials work good .



http://3dprinterstuff.com/shop/article_66/1.75mm-ABS-Filament---Black%2C-1-lb.html?sessid=YAlgdOEHxZCYqUIhhOU94JcbCnJcSctOOdrwkKCFvGDFCruW42w28Z4INC0oFX3D&shop_param=cid%3D6%26aid%3D66%26