Print Quality issues (pictures)

[catalyst]

it really is interesting. Pretty much everyone at the tct show was using pla and most when asked just thought abs was an awful out of date material and wouldn't use it.

And yeah for the shrinkage thing - just adjust the size before printing.
It's not a major problem - but it is a 'thing'.

So have you enclosed your creator sebastian ?
I still have a lot of abs on the shelf - thinking about enclosing the klic'n'print and trying it in that.
Mind you I've got used to my workshop NOT smelling of hot chemical plastic, so who knows :-)

oh yeah check out the material characteristics of polymaker's poly max. Pla that beats abs in pretty much all specs.
http://www.polymaker.com/wp-content/...PLA_TDS-v1.pdf

I find that all the ingeo based filaments I've tried are just really tough. The parts I make that undergo the most stress, have always lasted longer in pla than abs.
Like all things it's swings and roundabouts - I can only go by what I;ve made and how well it's done what i wanted it to. And in that respect pla always out performs abs.

I guess the acetone smoothing could be a positive.
I'm just glad I don't have to use it any more :-)

The thing is that bot pet and polycarbonate are generally better than and and print easier. Prices are coming down and pla is improving all the time.

Abs is cheap :-)
But for me the warpage, smell and reliance on acetone just massively outweigh any potential benefits.

PLA doesn't have the strength that I need. ABS does - at least in the filament I own. I also believe that I have clogged my extruder or the filament feed system, because I'm getting a clicking noise when it prints, or when I go to the menu and feed filament. I've read that it is sometimes dust buildup in the tube, which may also be clogging my extruder?

I would be curious to see what the ABS prints look like in a correctly configured printer.

I have two other issues/questions:
1. One of the things I notice with rafting and supports is that my bottom layers (or underside of the build object) aren't anywhere near as clean as the top and sides. What is that an indicator of?

2. I'm not sure how to resolve that, either. So for clarification as to my parts not fitting - when I print shells - do those count against my tolerances - if so how much? IE, if I print a 2mm radius circle cutout, will a 1.99mm object fit into that? How do I know how much room to give the build so the objects freely fit inside?

[JohnnyV]

I have two other issues/questions:
1. One of the things I notice with rafting and supports is that my bottom layers (or underside of the build object) aren't anywhere near as clean as the top and sides. What is that an indicator of?

2. I'm not sure how to resolve that, either. So for clarification as to my parts not fitting - when I print shells - do those count against my tolerances - if so how much? IE, if I print a 2mm radius circle cutout, will a 1.99mm object fit into that? How do I know how much room to give the build so the objects freely fit inside?

For 1, The part in contact with the raft will never look like the other surfaces. The bottom slightly fuses with the raft layer, so there will be some defects when you pull away the raft. The look can be improved, but only to a point. You can tweak the raft setting in S3D. My settings for Inland ABS are:
Raft layers 2.
Offset from part 2mm - how far from the each of your part the raft extends (I'm thinking about bumping this to 2.5 or 3 because I've been getting some curling).
Separation distance of 0.2mm. This is how close the part is to the raft - higher values will have less impact on the look of the finished part. Make it too high and the part won't stick to the raft.
Raft infill of 70%, lower values make the raft easier to remove but can affect the look negatively.

For 2, it kind of depends. This will vary a bit from printer to printer and how well it is calibrated.
Instead of drilling and tapping holes, you may want to consider knurled inserts, (sometimes called "press fit expansion inserts"). These are metal inserts you just press into the part, you can then use a machine screw into the insert. They are more forgiving on hole tolerances. I've used them on several models and they work great and look more professional.

http://www.mcmaster.com/#inserts-for...3bm0xfifmietqj

[jfkansas]

For 1, The part in contact with the raft will never look like the other surfaces. The bottom slightly fuses with the raft layer, so there will be some defects when you pull away the raft. The look can be improved, but only to a point. You can tweak the raft setting in S3D. My settings for Inland ABS are:
Raft layers 2.
Offset from part 2mm - how far from the each of your part the raft extends (I'm thinking about bumping this to 2.5 or 3 because I've been getting some curling).
Separation distance of 0.2mm. This is how close the part is to the raft - higher values will have less impact on the look of the finished part. Make it too high and the part won't stick to the raft.
Raft infill of 70%, lower values make the raft easier to remove but can affect the look negatively.

For 2, it kind of depends. This will vary a bit from printer to printer and how well it is calibrated.
Instead of drilling and tapping holes, you may want to consider knurled inserts, (sometimes called "press fit expansion inserts"). These are metal inserts you just press into the part, you can then use a machine screw into the insert. They are more forgiving on hole tolerances. I've used them on several models and they work great and look more professional.

http://www.mcmaster.com/#inserts-for...3bm0xfifmietqj

Rafts shouldn't even be in an experienced 3d printer user's vocabulary...

+1 on the threaded brass inserts, they are nice if ultimate strength is needed. For me generally either there isn't enough room for an insert or threading into plastic is good enough.

[JohnnyV]

Rafts shouldn't even be in an experienced 3d printer user's vocabulary...

This is a matter of opinion. Rafts have their place and benefit. I've worked for a professional rapid prototyping firm in the past using extremely expensive Stratasys machines with amazing engineers. You'd be surprised how often a raft is used. If you want the best quality and accuracy, rafts are the an excellent starting point.

Don't be so narrow minded.