Key tools for post processing

[ppolla 6]

What are the key tools for post processing PLA prints?

What should I get?

Please share. Thanks.

[ivan-lipunov 15]

Self-made infernal device from the solder station and metal parts from an old manicure kit.

[Labern 774]

My favorates are a modeling Knife and a Blowtorch

[ppolla 6]

Self-made infernal device from the solder station and metal parts from an old manicure kit.

 

Ivan, sorry dont get this...how do you use it?

[IRobertI 520]

Sorry

To be serious, a deburring tool is great for getting rid of brim (which I never use unless I absolutely have to).

[yellowshark 153]

For cleaning up a print, then I use a modelling knife and a set of files. If you can then pay for a set of proper jeweller's files; they will do the job better and last a lot longer

[JohnFox 25]

A set of needle files.

Wet and dry emery paper, grades from 120 to 400 mesh size.

I also use a woodworkers belt and disc sander. Runs rather too fast but with care it can smooth the surfaces quickly. ( the items I am making tend to be regular solids with flat sides ).

I like the waste paper basket suggested by |Robert|

Edited January 18, 2016 by Guest

[ivan-lipunov 15]

 

Self-made infernal device from the solder station and metal parts from an old manicure kit.

 

Ivan, sorry dont get this...how do you use it?

 

The idea I saw on one of the Kickstarter projects. In my case the meaning was in the replacement soldering tip for universal holder. In combination with the temperature control it turned out to be the perfect solution.

[skinny-kid 65]

Dremel rotary tool with a host of different attachments. Sanding disks, wheels, brushes, buffing pads, etc etc

[JohnFox 25]

What speed does the Dremel run at? Do you get problems with heat build up at all?

On my belt sander I have to take great care not to get the parts warm, it's very easy to melt them.

 

Dremel rotary tool with a host of different attachments. Sanding disks, wheels, brushes, buffing pads, etc etc

 

[neotko 1,417]

For dremel action I use a small rock polisher (uses 2 AAA batteries) and works nice since it rotates much slower. With my dremel 4000 It melts too fast indeed even at the lowest setting.

[neotko 1,417]

Also today arrived my sandblasting cabinet. First tests with soda (to avoid dangerous stuff on my house) look quite alright. It leaves the pla without bright absolutely matte.

I need to buy a harder abrasives, but safe ones are limited. Anyhow when I learn more and have something to show I'll post some photos.

[yellowshark 153]

Hi @neotko I would be interested to know what brand/model of sand blaster you got. It is something I have thought about for a long time but I have never actually jumped in.

[neotko 1,417]

Well I bough the cheapest posible that could 'work'. I got a 4-6bar compresor very compact for 200€. The noise (for a compresor) it's quite acceptable. Also got a blaster gun called air eraser from the same shop as the compressors and drilled the nozzle because with its 0.5mm nozzle the soda wasn't working (it's designed for aluminium oxide) but now with a 1.5mm hole it's ok. Also got a 110€ enclosed cabinet to avoid the need of mask/etc, very nice btw but I need to check the seals since there are two points where it leaks soda.

Any pro will tell you that my compresor sucks for sandblasting, and it's true. This is a 1/2hp 3l tank and it's quite small. That means that I must wait from blast to blast. But also, I don't plan to be blasting all day, but for just a few objects a day while printing, so it's ok.

Now I need to buy non-tonix blast stuff to do more abrasive action, but also for the moment the soda works for the matte effect ans removes that 'printed' felling and it hides the mistakes at the untrained eye (soda so far don't erase the printed lines since its quite soft). Also I'll need to design an adapter for this blast gun, because it can only hold 30mg of media. The blast gun that arrived with the cabinet has a 5mm nozzle, and for that you really need a bigass compresor with a big tank to hold the air.

Oh the brands, sorry forgot... It's a fengda compresor with tank (quite small model 189 something) and the cabinet it's rptools. Quite cheap, nice quality. I been reading and seeing videos about this for 3 months before jumping in. Ofc I knew the compresor was going to be not good enough, but for good non-stop blasting the compresors and tanks are heavy, big and really expensive.

Edited January 20, 2016 by Guest

[skinny-kid 65]

What speed does the Dremel run at? Do you get problems with heat build up at all?

On my belt sander I have to take great care not to get the parts warm, it's very easy to melt them.

 

Dremel rotary tool with a host of different attachments. Sanding disks, wheels, brushes, buffing pads, etc etc

 

 

I also use the dremel 4000, it has variable speed setting from 5-35k rpm. The most I have gone to is 15k. It can melt the plastic if you aren't careful. Dremel makes a few different grades of sanding pads. They have disks also but I find the pads work well. They are rounded and allow you to work into curved areas without difficulty.

Edited January 20, 2016 by Guest

[yellowshark 153]

ditto @skinny-kid although I do use jeweller's files a lot more than the Dremel.

[Labern 774]

You might find that support roof should help prevent a lot of the filing that you used to need to do. It makes it a lot smoother. Since I have used that feature all I need was a couple of scrapes with a knife at 90degees then a quick flame to get rid of the white bits.

[cloakfiend 995]

Nothing but acetone for me now (no surprises there, lol). I dont even bother sanding anymore. Zero effort, but near perfect results. I would tend to sand flat stuff though with 400 grit sand paper.

Edited January 21, 2016 by Guest

[gareee 39]

Nothing but acetone for me now (no surprises there, lol). I dont even bother sanding anymore. Zero effort, but near perfect results. I would tend to sand flat stuff though with 400 grit sand paper.

 

I thought acetone didn't work on pla?

[dergoldstein 1]

General-purpose: Flush cutters (often to remove the slight brim on the first layer), xacto knife, small (jeweler's) files, small pliers (to remove supports), sand paper.

I also print a lot of mechanical parts that need to be press-fit, screwed in, connect snugly to other parts, etc, so I use some tools that others might not:

Drills, reamers, and countersinks -- you can print pretty accurate holes when they're on the z-axis, but otherwise you need to drill them "the rest of the way" to smooth them out (just make sure the wall thickness is enough so that you don't poke through to the infill).

Taps -- both PLA and ABS can be easily and effectively tapped, I use this a lot. Most often M3, but also M2, M4, and M5. Don't rotate the tap too quickly though, especially with PLA, or it will melt the plastic.

Loctite "Super Glue Gel" -- Loctite probably makes hundreds of different glues and I can't give you a specific product number, the label just says "SUPER GLUE GEL". I use it to connect PLA prints, it's quite strong. It being a "gel" lets you accurately position the glue without dripping or spreading. The only downside that I know of is that it discolors the plastic around it a bit (usually turning it a bit white).

[MarcusWolschon 7]

 

I can still see a lot of lines.

Probably polygon-edges and not layers.

Are they gone after a slightly thicker color-coat?

What kind of surface-quality do people find acceptable and

do are your models convex with flat surfaces or concave and highly rounded?

That makes a ton of differences in how it can be post-processed at all.

[cloakfiend 995]

The vertical lines are speed related lines which are more visible the faster you print and the thinner the layers, i have no idea how to remove them other than print slowly, but i'm very impatient and want things quickly and effortlessly and cheaply like many other people out there so i tend to push the speed and flow a bit too much. From a very perfect point of view, if you analyzed it very close, subtle lines are still visible, but even for me they are not a problem. These layers are not visible after an under coat, you will always see the layers after post treatment in some form or another, but the sacrifice is that you lose definition the more you smooth. If i wanted something very smooth i would first give it a very light sand to scrape of the tiny imperfections of the printer, then treat it longer, then buff it and it would be perfect. But you need to be careful as too much acetone can crack your model, even many months later! and aggressive post work can also damage the quality!

There are a few other chemicals like thf and dioxane and chloroform that smooth PLA but they are more expensive and much more toxic, and start to literally eat the pla which is not what i want, i personally prefer subtle lines that i can sand away compared to the melted ABS vapour look which destroys all details. If you want it shiny, then just spray it with gloss.

My models are sculpts mainly from Zbrush exported directly as OBJs and clean up very easily after prints, the one above was not sanded and you can see how it looks in the print section after a metal coat, but here is a pic anyway....

You can see other surface treatments of this object (painted on) in the prints section if you are interested to see what the undercoat looked like, or the matt coat....

Edited February 25, 2016 by Guest

[gareee 39]

Rustoleum Bright coat metallic silver has a levelling property to it thats great for smoothing out lines without sanding, but the tradeoff is it also fills in small details. Here's a witcher 3 medallion I didn't sand at all.. I just applied several coat until i got more of a "cast metal" look.

[neotko 1,417]

That lines also can be related to the number of 'steps' the slicer uses to make the print path. The faster you go the less time has the nozzle to 'blur' and smooth the print. So, with other slicer that could let you choose the amount of paths for each part (s3d and slic3r I think also) you could print faster. Ofc there's a point where too much paths/sec can make a bottle neck on the 8bit processor, but that's other history...

Edited February 25, 2016 by Guest

[cloakfiend 995]

Rustoleum Bright coat metallic silver has a levelling property to it thats great for smoothing out lines without sanding......

 

I agree because whatever you do, if you have lines, you will inevitably reduce the detail in your model which is why i like to print high and either over paint, or simply coat my object in a way that i keep going until the lines are gone. There are many many ways. Mine is not the only one obviously but its very easy and you dont need to overspray which i find can make some areas bulge on flat surfaces due to the paint rolling according to gravity, chemically treating it means you dont need as much spray hence avoiding this issue, but it all depends onthe look you are going for or you just need to use more smaller layer of spraypaint. Your witcher medalion looks really nice btw and the metal look real! lol

The only real alternative is to print it with a different printer but that will cost you more money which is what i am trying to avoid as a hobbyist.