Smoothing printed 3D parts

Hey guys, trying to complete a 89 grappel gun I've had for a while, most parts have those tiny lines on them, which I havent been able to sand off. I need a product that will smoothen the surface without adding thickness to the parts...any suggestions? By the way my grappel will have a retracting rope, the trigger will "function", so your help will realy help me move this project forward!

just noticed the xtc3d from smooth on, did anyone try that one?

You didn't mention what the print is made from but...

If it's ABS, then you can use Acetone vapor (cold or warm) to smooth the surface. Basically the vapor eats at the surface causing it to melt. You do this in a container with visible walls/top so you can stop the process when you're most of the way there. There are a bunch of tutorial videos on YouTube, strangely enough, mostly by Australians.

You can also apply a two-part epoxy with a brush. While this does add material, there are products out there that will also eat the print substrate so that what you're adding is negated by some removal and you end up with something just about the same size as you started with. Last video I saw was with the 2-part from ZAP (Z-Poxy), but Smooth-On also has one (XTC-3D).

I had quite nice results with the acetone vapor method. Using a clear glass container is crucial so you can oversee the process. It only works with ABS, though.

Edit: Image / this Baymax fig was only treated with Acetone vapor.

I always find the best method is a combination of filling and sanding. The trick is to not just glob on the putty, paste or bondo. Instead, you want to carefully smooth it into the surface. Then it is primarily filling in the low spots (the grooves) but not building up the surface contours. After it hardens, the sanding process is easier too because you aren't having to sand through a layer of filler to get to you part's surface.

For fine but deep grooves, there are "high build" or "high solids" primers that you can spray on your part, and then sand. These primers have more stuff in them so they fill in the grooves and sand away easily.

In any case, careful sanding is the key. I'm not a fan of the solvent method because it softens the crisp detail I want to keep, but if your finished piece is supposed to be soft, then have at it.

Wow a lot of good advice thanks! The vapor method kinda scare me lol! I might go with the smooth on product, than maybe a primer if not enough, than sanding. That should amount to something decent, I hope.

duplicate post

I've used xtc3d from smooth on, and had great results. Smells like no tomorrow, but works great.

C