Material question - Metal alloy plastics


(Dylan) #1

Hey all, I’m wondering if anyone has any general information on metal-alloy plastics. I’ve seen several names for these types of materials and a zinc/ABS plastic combination seems to be fairly common but they are typically injection-molded and used for products that need the look and feel of metals but are based in plastics.This is often used for replica or airsoft guns, and similar products:

So two general questions:

  1. Does anyone know if these materials can be milled?

  2. And if so, does anyone know where one might find raw materials for purchase?

Thanks in advance. I’m doing some digging around a few other forums so i’ll followup if I find anything elsewhere.


(Andrew Van Lahr) #2

Interesting question… Ecomass is a company that produces a lot of this type of material, and I’ve worked with them in the past.

Most of the materials out there based on plastic-matrix with metal powder the plastic is the primary mechanical component, and the metal is only added to add weight/mass to the material, and the metal is milled fine enough to pass through the gates of the injection molding machine.

I am a little surprised these materials are being used for airsoft guns, as they’re generally not very strong, and they’re relatively expensive for what they are. They were originally made for hybrid radiation shielding (mass for gamma, hydrogen for X-ray and neutrons).

I have had this material “in bulk” it was in the form of sheets, and was asked to machine it, it does machine fairly well, but you need to provide a lot of support, as it seemed rather easy for the material to crack and crumble. I might drop the tool speed, and keep with a low feed rate, you don’t want to melt it, but you want to make sure you’re getting good material removal and not putting a lot of force on the cutting face. You may want to try HSS tooling as this is typically sharper than carbide, and conducts heat better than carbide does.

You might want to check, because I would think these parts would be made of Zamak or some other die-casting alloy.

I’ll dig around, and see if I still have some of that material, if so, I’ll send it to you (trying to clean the garage anyways).


(Dylan) #3

Thanks for the info Andrew, and I’d love to take some off your hands if you’ve got some extra. I’ve contacted a few manufacturers to see about getting test samples as well so we’ll see if I can get anything interesting. I haven’t seen any direct online sellers for small quantities yet but I’m still doing a bit of digging. There are a lot of different variations and names for these sorts of materials so I’m still getting familiar with the vocabulary.


(William T Stokes) #4

I have used the powdered metals in several types of resins from ready to cast mixes like Smooth-on CastMagic to my own recipes to get titanium and other metals in the mix… The best way I have found to use these are either by making a Wax replica/mold and pouring or by painting them on. Materials costs are high as the powdered metals are generally expensive, some quite so! I have used the powders as metal flake-mixing them into the resin/paint, and used the paint as adhesive(like “Shake and bake” on chicken).
I have bought powders off ebay, and from companies that I expected would be sanding the base metals in their typical operation-though it is tough to get the right person to ask on the phoneas it is easier for them to say no and get back to work than it is to say yes and add to their day…