Modifying 3D printed parts

[matteekay]

Hello to the filament flingers!

I recently bought a set of magazine extensions that have clearly been 3d printed. They look like this(ish):



I'm not using them for the intended gun so the top edge of the extension interferes withe bottom of the magwell and prevents the mag from seating. I need to shorten them up slightly but I'm totally unfamiliar with printed materials. Any recommended tools? I assume a belt sander is going to obliterate the extensions so should I be doing something like a Dremel with a cutoff wheel? Or just a hand file?

[Rainmaker]

Depending on how soft the plastic is, and how thick the section you need to remove, you could probably use a good sharp knife and just carve it away. Other good options are hand filing or sanding.

The trouble with any powered sanding tool is that it will heat the plastic up pretty quick and either have potential for warping, or you get a blob of plastick shavings building up on the downstream side of the sanding.

You might be surprised at how far you get with just a sharp utility knife.

[tjd10684]

A fine file and or wet sanding is your best bet. Like rainmaker said almost as soon as you touch it with a powered sander your going to melt it. While an utility or exacto knife will work I have pulled too many slipped blades from my hand to recommend it. It might not matter for your application but if you remove too much you might get past the surface layers and into the fill volume.

[matteekay]

This is the exact sort of info I was looking for. Thank you both!

The top of the extension is somewhat angled and I'm concerned a knife is going to slide off/out. I think I'm going to start with a file and see how it goes. I shouldn't have to remove much.

[JonM]

Another thing to be aware of is that unless these were printed solid, removing too much material may expose the hollow core and infill. The outer walls are the strongest part of the print.

[Rainmaker]

^^ Very true.

Another thing you could try if you find that the walls are really thin, is to use a soldering iron or similar to mush the plastic down in the areas of concern. Kinda hard to get it to stay looking nice, and if you heat it too much you can have warpage, but I've done this before in some cases.