We are attempting to print some single-use prototypes using an SLS printer. The parts must be somewhat water-resistant for short-term usage, but do not have to been waterproof entirely.

According to this page, Post processing for SLS printed parts - Water tightness, any silicone type or vinyl-acrylate sealant should work well, but I was hoping that the Stack users here might have some specific suggestions.

Does anybody have specific recommendations for sealing SLS prints?

  • $\begingroup$ I think it's going to depend on two things: what is the material made out of (for the print) and what are you trying to seal it against? Water is going to be different from alcohol which would be different from oil. If you wanted to seal it against acid, that'd be an ever bigger challenge. $\endgroup$ Commented Oct 17, 2019 at 18:15
  • $\begingroup$ All of these prototypes will be tested in water. Further prototypes will be constructed of cement and used with an oil-based fluid. Material is “Versatile Plastic” from Shapeways. I believe it is a Nylon. $\endgroup$
    – JPeroutek
    Commented Oct 17, 2019 at 18:20
  • $\begingroup$ clear spray acrylic sticks to most things and is completely waterproof once dry. $\endgroup$
    – dandavis
    Commented Oct 17, 2019 at 18:23
  • $\begingroup$ Most SLA resins are water resistant, while nylon SLS could be dunked in resin to get it into all the print. $\endgroup$
    – Trish
    Commented Oct 17, 2019 at 18:27
  • $\begingroup$ @Trish Wouldn’t a resin bath require a UV laser to harden it? We opted to use SLS over SLA due to a 300% price difference. $\endgroup$
    – JPeroutek
    Commented Oct 17, 2019 at 18:30

1 Answer 1


SLS prints from nylon are somewhat porous. This means, that they will let a stabilizer soak into the outer surface to some degree.

What kind of stabilizer is needed is depending somewhat on the properties you want, but generally I believe these might be useable depending on the viscosity:

  • 2-component resins could be used, but they are usually very viscous. Their viscosity, however, is dependent on the exact type and mixture and could be altered by temperature.
  • 1-component (air-hardening) resins or resin lacquers can be thinned to achieve a solution into which the item is then dunked and dripped off. How much thinner is adviseable depends on the exact material
  • Nitrocellulose lacquer, like it is used in guitar building, is extremely fluid and could be used for treatment via dunking.
  • PU lacquer could be used too.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .