Putting PLA parts in the dishwasher, huh?

I was reading around and I found this thread in the Ultimater community forum: Using new ColorFabb XT Transparent PLA.
Since I don't want to create an account there just to ask this and I don't have an Ultimaker I'd rather ask here.

They mention putting parts in a dishwasher at 70 degrees, that is... interesting. Is it to bake the PLA to improve the inter layer adhesion?, or to smooth out the layer ridges on the surface? I couldn't find any other mention of this technique anywhere else.
The quality of the prints shown there are astounding, so they must be doing something right!

It looks like it is purely for looks, although there might some science behind it. Putting it in the dishwasher causes the print to turn a very white color, as seen in the picture with the skull from the thread you linked to.

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gmh39
It looks like it is purely for looks, although there might some science behind it. Putting it in the dishwasher causes the print to turn a very white color, as seen in the picture with the skull from the thread you linked to.

So it only affects the colour, not the surface finish?

Give it a try and see what happens, I would.

I tried it yesterday, apart from a faint milky appearance in the top of the part, probably from residue, I can't really see any difference. The part was printed with green PLA.

But now I have a clean part..

Maybe PLA Sous Vide should betested out, this is after all a more controlled process than the dishwasher.

Old dishwashers used to have massive heating coils for drying. They got so hot that some people even used them for automobile engine parts washers to remove paint and grime from things like valve covers.

Modern Energy Star dishwashers do not have those energy-wasting massive heater coils, instead using tricks like heating the final rinse water to raise the internal temperature a few degrees to speed condensation.

Before condemning the process, it would be a good idea to find out what type of dishwasher was used in the original post and make sure that you are using a similar appliance.....

I've tried it with PLA at 100°C water for 10 minutes, no effect. And the steam in the dishwasher can't be hotter than that, since the washers aren't pressure-proof i guess. So that's probably a myth, or it only does apply with certain materials.

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daveb500
Give it a try and see what happens, I would.

I don't have a dishwasher, I was just mystified at what this technique was supposed to do.

Color XT is not PLA, which probably explains why PLA is not behaving as expected. ColorFabb says (Color) "XT was developed to be an alternative to our PLA/PHA range." The Ultimaker community forum heading is incorrect.

That's right. The XT isn't PLA and the heading of the Ultimaker forum is incorrect. It's a PET copolymer I believe. Similar to t-glase and other PETs but with different copolymers (i.e. colorFabb's secret sauce).
XT whitens in the dishwasher. It is definitely a cool effect, but purely cosmetic. It might also warp the part a bit depending on how hot your dishwasher gets.
It can be vapor polished similar to ABS. I tried it out here: [www.printedsolid.com]
Since then I (and others) have tried it more and haven't really found a magic recipe to getting it to work consistently like it does with ABS. I'm guessing that there might be an issue with some atmospheric factor (pressure or humidity) since it works great some days and horribly the next for similar parts. I've also tried it on t-glase and PET+, with some success but it seems to be best with XT.