FUD post-processing suggestions

This thread is for discussion of post-processing the Shapeways material Frosted Ultra Detail (FUD).

Personally, I use an product available in America called Bestine (chemical name heptane) to clean any wax off the surface of the material. The advantage for me is that the chemical also turns the surface of FUD an opaque white. What is interesting is that it seems that in this condition, acrylic paint will adhere much better to FUD (as though it had been given a coat of primer paint). At the same time, it doesn't suffer from loss of detail created by a thick coat of paint.

Now, I also know that Bestine is a noxious chemical and should be used only in a well ventilated environment. I have heard of other people who swear by Acetone, FurniturePolish, ultrasonic cleaners, diswashing soap, and several other choices. I work with several patrons who each have their own idea of what is "best" to use. Most of that is the particular experiences of the buyer. I think that it might be best if Shapeways could start offering FUD that has already been processed in this manner - however I know some folks who are after the nearly transparent features of FUD.. Perhaps it could be two products?

One thing that is clear to me (irony) is that we need to work on describing FUD (and TD) better. We need to stop using the word "Transparent",
It is quite obvious that FUD is not see-thru, but neither is it opaque as in "blocks all light".

Translucent is the proper term I guess, but you are the native speaker...
One thing I noticed when searching this forum is that people used to report quite different results with the various cleaning methods proposed - did (or does) shapeways use different support material at times, or possibly even depending on NL vs. US factory ?

Total rumor, but I think they had a change to the machine such that they started using a different support material.
If you watch one of the most recent videos, they now do some of the cleaning with a jet of hot water, rather than just cooking it in an oven.

Actually after looking again at stop4stuff's "kraken in aspic" here, calling FUD translucent instead of transparent would not seem to do it justice either, even if it may not be perfect enough to allow reading a paper through it.
It seems the secret does lie in surface quality - be it sheer luck with print orientation, lots of sanding or filling the scratches with some clear material of similar index of refraction.

The bulk FUD material seem quite transparent.
I guess the optical properties of an object made with FUD lie in the surface roughness.
Anyone tried FUD coated with a glossy varnish ? That should increase the perceived object transparency.

I recently received my first models, among them one in FUD. I was surprised to find some kind of soft wax all over the surface, and more surprised that the Shapeways support couldn't even tell me what it was, much less how to remove it. ("might be leftover waxy support material" ... "may also be the oil that we use to clean the materials as well as give them a nice smell." - nice smell???)

At least they pointed me here.

So I want to clean my model, and apperently I'm not the first. I intend to paint the model with acrylic paints, and I'm pretty sure they won't stick on wax. Since this is my first batch, I'm especially worried that I would use a substance that would dissolve the model, that's why I plan on using soap and an electric toothbrush. Any experience with this? Are the bristles too harsh for FUD?

If that does not work, I'll keep the tip about the heptane in mind.

Citrus oil can be used for degreasing, it would leave a lemon odour - something that customer support may have noticed without knowing for certain if it is intended or just a side effect. Without seeing the piece in question, how would they know which of the two likely processing steps the residue might be from, and the cleaning method required would seem to be the same anyway (something that removes nonpolar "fatty" goo).
I do not think the acrylics would be scratched by the toothbrush - small things breaking off might be the real danger - but I would start with just the soap (dishwashing liquid) solution and wait to see if the goo really needs mechanical coercion. Note that the material will become plastic in hot water (which can be used to straighten distorted parts if necessary)

Before I continue, let me acknowledge that this is a very minor gripe, overall I am now pretty sure to have a handle on the grease.

As I said this was my first model, and I haven't read anything about the grease before. My service call first got the response "wax, but couldn't be sure, please send in pictures", and I'm pretty sure the grease would not have shown. The oil was only mentioned in the second mail, and I was send here for a solution (I pun!) to remove them. I think the response should have been something like "could be wax from step A or lemon oil from step B, here is how you can identify the two, and here is how to remove them." (Unless there is a third candidate.)

I'm not sure how I would check for residues, and since I'm also new to the painting business I don't want to take chances.

Good point, I will treat it like a baby!

Thanks!

When you're cleaning a FUD model with Bestine are you just soaking it in the stuff or using some sort of applicator (toothbrush etc)?

And what do you use to clean the Bestine off with? I assume running it under a tap is a no-no.

And for anyone in Australia looking for Bestine, reports indicate that Un-du Adhesive Remover from Bunnings is chemically the same stuff. Untested by me, though I intend to try it this week when I get down to the shops.

EDIT: Also does anyone know a good dye for FUD? I'm thinking I may need to dye my piece rather than paint it because of some pretty fine details.

Hello,

We made a small 'tutorial' in our tips and tricks page: http://railnscale.com/tips-english/

Best,
Maurice
RAILNSCALE

I use 99% isopropyl alcohol to clean my FUD parts. I soak them for about a minute, gently go over them with a soft toothbrush, rinse them in the alcohol bath, and set them aside to dry.

This works well, doesn't damage the part, doesn't contain any nasty chemicals, is inexpensive and easy to find, and removes any oils from the surface to ensure excellent adhesion of paint. I always use acrylic paints on my FUD parts.

Steve Hunter

I believe this is what I came here looking for. Can anyone else attest to the success of isopropyl alcohol for cleaning FUD? I have several 54mm mini characters that I believe need some sort of cleaning. It's hard to tell for sure, but there appears to be some residue that really stands out against the material. There is contrast between opaque parts and translucent parts - not sure if this is inherent or something that should be cleaned off.

I neglected to mention that sometimes (infrequently, thank goodness) there's a heavy wax buildup on some surfaces- a lumpy white surface, which I believe is what you're describing.

After doing the alcohol thing, I always lightly sand my parts- since I do railway models, I need a good smooth surface finish.

If the layer is a little too lumpy to sand down, I'll scrape it off with a single edge razor blade or hobby knife, held at a steep angle to the part. Pull the blade back, so the sharp edge is dragging across the surface rather than cutting into it.

I often encounter surfaces which are nice and smooth, but are white- in those cases, I just do my light sanding, typically starting with 400 grit emery cloth and finishing with 800 grit.

My parts all receive a light coat of acrylic paint, which allows me to ensure the surface and detail quality is good, after which I finish assembling and painting the model.

I hope this will help!

Steve Hunter