This is a method I developed a few years back for my day job. We needed watertight containers made from PETG as we were handling chemicals that would easily diffuse through - and break down all other commercially available thermoplastics.

After some trials with sand I started using finely ground salt. It perfectly immobilizes the parts, and gets only superficially embedded. Once the parts are baked, the salt will have superficially embedded itself into the part surface. Washing the part in warm water will dissolve all the salt, leaving behind a sparkly texture.

This technique opens up a whole new dimension for makers. Not only can we make our components much stronger, we can now cheaply prototype valves, pressure vessels, hose fittings etc., without having to rely on resin printers.

This method does have disadvantages though. It takes quite a bit of labor and it limits the depth of undercuts that can be used. Hollow parts need to have an easily accessible hole.

Any question you have, write them in the comments…