How do you post process (clean up) your parts?

I am wondering if anybody out there has a good/unique way that they clean up or post process their plastic parts, that they will share?

I mean to flatten (or round/shape) the parts after they are printed... beyond just the knife/x-acto...

Does anybody clean their parts up with a grinding wheel? or a dremel or a heat gun or something? Iron? sand paper? How about jig it up into a subtractive CNC and profile it?

I'm just wondering if somebody out there can share a way to make their parts perfect...it really irks me that my printed parts are 'wiggly'... I want perfect looking parts! I wish I could afford an injection mold machine >.>

Well, are you all just happy with your giant (.5mm) lines in your end product? or do you do some secret post processing stuff? please share ideas, experiences, successes?


I just have been 'whittling' with an x-acto knife to make it look a bit better...but it still looks crappy >:/ I may try using a clean dremel grinding wheel later...actually right now What do you guys do?

i haven't printed, but i've recieved reprap printed parts, made a silicone mould, cast it in polyurethane resin and then sanded down with a belt sander/hand sanding. kinda convoluted but resin is much easier to sand and drill, (but bad for yer lungs)

An injection molding machine is next to useless without molds, which are hard to make without a subtractive cnc and or edm machine. Even in a cnc mill detail isn't free, the smaller the stepover (closer together each successive pass is) the longer it takes to cut the part. Then you need to consider what kind of tool you can get in where you want to cut, and how. A .0625" ball end mill for example is going to leave a minimum inner radius of .03125". That's a relatively small end mill, but it will still radius inside corners worse than .5mm. Depending on part geometry it may not be easy to get the tool where you need it, requiring fancy programming/CAM raising cost and skill level.
One of the great appeals to this kind of tech (at least in my eyes) is that within the bound of the printer and media you don't have to think much about how to actually produce the part. Draw it in 3d and print. No hours spent programming and verifying, no figuring out complex fixturing, just print.

I reduce the amount of mechanical finishing by flowing cyanoacrylate glue over pieces. The discount stores here in Sydney sell ten 3g tubes of cyano for $2. Capillary action carries it along the steps, and a whiff of accelerator sets it. A first application "fillets" the steps, subsequent applications fill them, and it's very controllable and pretty quick. Accelerator is stinky, so I do it outdoors, but rolling the piece around to encourage flow is a lot less demanding than using files, knives, et al.

Once you've made 'em look nice, slush molding copies in elastomeric molds gives almost-injection results with a lot less overhead.

This is the advice AKA47 put on my blog: -

1. Spray with high build primer.
2. Smooth with Wet n Dry grades to get desired finish. Iff too many indents goto 1.
3. Spray with preferred choice of finish.

The primer is easier to sand off than the original plastic.

Or you can use a solvent, sanding and paint [blog.makerbot.com]


Or you can just keep adding layers of paint until it is flat. [blog.makerbot.com]

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[www.hydraraptor.blogspot.com]

To nophead:

Quote
http://blog.makerbot.com/2010/09/01/how-good-can-a-makerbot-printed-object-look/

ah cool ok. I never even heard of plastidip...thanks!

so, he dipped it in watered down acetone and then used abs cement and grinded it with a dremel and then used some Plastidip to make it look uniform...amazing result! lots of work but I'm encouraged that we don't have to settle for this : [www.flickr.com]

To koko76: I actually have a subtractive CNC and ball endmills and know that it takes longer but I can get perfect results with my subtractive CNC...I could make molds too in aluminum I just can't afford an injection mold machine...i was just day dreaming for a second


To murrayd: So you cover your printed parts in liquid super glue? (CA) Do you have any pics with results?