How to get top smooth

I've been working on a loading block.  I can print at either .19 or .29, low speed, solid with 20deg angle support with normal seam and fan on auto.  This is in black ABS. I'm doing surface layers of 4, both top and bottom but can't get the surface to come out nice and smooth.  Any suggestions?  Thanks!

I've been working on a loading block.  I can print at either .19 or .29, low speed, solid with 20deg angle support with normal seam and fan on auto.  This is in black ABS. I'm doing surface layers of 4, both top and bottom but can't get the surface to come out nice and smooth.  Any suggestions?  Thanks!

… with printing 0.9 ?

Sand + clear coat, or try standing the part up so there are no flat faces.

I haven't tried .9 yet.  I sliced it at .9 and it added over 11 hours to the print.  I need to make quite a few of these.  Never thought of standing it up.  I may send off for injection molding.

Try Acetone vapor smoothing, it can rival injection molding for surface finish if done right.

Look for posts by myself here and in the PP3DP forum for the best technique.

i use hot air, like the type you would use with desoldering surface mount components

about 240*C for lighter shades of Z-ABS....

darker shades need about 260*C - 265*C

use fast swipes across, 1 to 2 seconds in needed area...

dont let the hot air stand to long in one spot else it can warp the design

its a lot faster and safer than acetone

...and you can score a cheap hot air machine for 40$ on ebay, WEP 858D

apologize for poor video quality, im still working out the kinks in my video streaming...

demonstration of hot air

https://www.youtube.com/watch?v=qh1WrlybIWU

That part looks familiar... :lol: :lol:

i use hot air, like the type you would use with desoldering surface mount components

about 240*C for lighter shades of Z-ABS....

darker shades need about 260*C - 265*C

use fast swipes across, 1 to 2 seconds in needed area...

dont let the hot air stand to long in one spot else it can warp the design

its a lot faster and safer than acetone

...and you can score a cheap hot air machine for 40$ on ebay, WEP 858D

+1 for the WEP 858D or whatever they're calling themselves these days. I never had the thought for using it for smoothing though, I'll definitely have to give that a shot. 

Very cool.  I've been using acetone and it works great on certain types of parts.  I'd never ran across the hot air technique and appreciate the intro and video.  I will own one of those as it will easily solve some of my issues.  THANKS!

Update.  It's on the way!

Just to be clear, the "Hot air" technique does NOT smooth the part surface, it re-heats the stressed plastic causing it to return to near normal color and if too much heat is applied it will cause bubbling of the surface as water is steamed and plastic gets soft.

it would be best to define smooth as follows:

if you define smooth as "glass-like finish", then only acetone will work..

if you define smooth as "surface refinishing" by eliminating traces of support material, then yes hot air can work..

keep in mind acetone does not work on all Z materials, but hot air will

That hot air machine looks like a lot of work and energy. lol

I just use a quick blast of a torch and it works perfectly. Cheap and quick!

That hot air machine looks like a lot of work and energy. lol

I just use a quick blast of a torch and it works perfectly. Cheap and quick!

I used to run an Epilog laser system a few years ago and used a catering torch all the time to finish edges etc. Fast and simple, and no wires! :)