Alternatives to Bestine For Shapeways Models

[thomasjmdavis]

I once tried using 91% alcohol to strip the paint off a FUD model. The results were sub-optimal -



I couldn't even begin to explain why that would happen 

Cheers,
-Mark

Was the 91% alcohol on fire at some point in the process?

[Dave Schneider]

Here are 15 pages of nonstop fun on this issue! At various places within this thread there are some discussions of cleaning FUD. 
https://www.therailwire.net/forum/index.php?topic=28137.0

Best wishes, Dave

[jimmo]

So...do all Shapeways products have this stuff on them that has to be removed? I have a couple things (truck tractor and trailer) that seem like they're pretty clean and ready for paint.

Not all Shapeways products, just the Frosted Ultra Detailed or FUD. Shapeways has a cleaning process after rendering the object but it doesn't always remove all the residue. I haven't had the wax problem lately but the stuff you have to be aware of is the loose unfused resin usually on one side of the object. I refer to this the tail end of the print pass. Most of it can be removed with a toothbrush. I find that I often have to scrape some of it off with an Exacto knife. If you go ahead and paint over it, you might end up with a crusty-looking surface on your model. I prefer to shoot some gray surface primer on my models before committing to a finish color, that way you can at least scrape and/or sand any rough areas you might have.

[James Costello]

So...thinking out aloud a little on this, seeing as Bestine isn't available in Oz

Bestine - seems to be 100% Heptane from the Union Rubber MSDS
HEPTANE is a narrow boiling range, rapidly evaporating solvent intended for use in the adhesive and printing industries and in other applications where low benzene and n-hexane contents are desirable.
http://en.wikipedia.org/wiki/Heptane
http://www.orcbs.msu.edu/msds/112906_ACP_006_BESTINE1.PDF

So, looking at what solvents are typically sold here, I came across Shellite, which contains Hexane and seems to be compatible with, or at least replaced by, Heptane. Shellite is an Australian form of Naphtha, which has come up in the discussions here.
"Hexane is a clear, colourless liquid with a faint odour. It is a stable paraffinic hydrocarbon which is highly volatile and distills
over a very narrow range. APPLICATIONS: Oilseed extraction, polymerization catalyst carrier, paint diluent, adhesives, sealants."
http://www.oilchem.com.au/products/solvents/hexane

"In many applications (especially pharmaceutical), the use of n-hexane is being phased out due to its long term toxicity. It is often replaced by n-heptane, which will not form the toxic metabolite hexane-2,5-dione."
http://en.wikipedia.org/wiki/Hexane

The MSDS for a common brand of Shellite has its proportion of n-Hexane as 10-30% so unsure how effective it will be relative to Bestine. Has anyone outside of the US tried Shellite in this application?

Shellite is also known as, or is at least similar to the solvent X55 (Shell) which can contain Toluene, but also has 10-30% n-Hexane.
"X-55 Solvent is widely used in the rubber industry. A wide Boiling Range and Rapidly Evaparating Solvent, that is highly flammable (Flash Paint <0 degrees C), can form explosive mixtures with air and is immiscible with water. Uses: It perfarms well in situations requiring a solvent that evaporates quickly with no residue."

Any thoughts from the chemists amongst us?
I'm a bit wary of soaking my first FUS print in either at this stage....

[Philip H]

I have never been completely sure what sort of plastic FUD is, but I wouldn't put anything with Toluene anywhere near it. Hexane MAY be ok but I doubt it.