Help with Aluminum " Floor Plate " for weapon

[Greg Bednar]

I am in need of some assistance on a particular job. I have been tasked with engraving the floor plate of a Remington rifle. I have contacted the company because I wanted to know if the piece was anodized aluminum and not simply blued metal. The man on the other end of the phone told me it was anodized, but I am inclined to disagree with him. I believe it is aluminum that has been spray painted black. I did a test engraving of a small cross which you can see at the top of the picture. It turned out a dull aluminum color since I think particles of the paint had contaminated the substrate in the engraving process. So I took some MAAS fine polishing creme which brightened the cross, but put a gloss finish on the surrounding flat black paint.

You can also see in the bottom of the photo where the flat black spray has not covered all the metal. So, I'm thinking I'm correct with the "not anodized" theory.

I used recommended setting on my machine for anodized aluminum, 100/45 at 600DPI. But I would like to get a more brilliant effect without using the polishing cream thereby not changing the finish of the flat black floor plate, and still have a shinier engraving.

Any thoughts on how this can be accomplished? Do I up the power to ablate the paint, slow down the speed. I don't have diamond drag so that's out.

[Mike Null]

Greg

I believe the surface is anodized but with a different process than you might be familiar with. I have never been able to get a shiny surface on anodized as I think the process does not permit it. I try to get a whitish effect and do not try to get to the bare metal.

Not expert on this but think the anodizing prep would knock off any polish that might have been there.

[Greg Bednar]

Thanks Mike. On close inspection I'm dealing with paint flaws, miniscule, but enough to effect an engraving ( obviously not a German weapon;) ) . There are also uneven surfaces on the face, but I can account for that with focus. But thanks for the info and fast response.

[Dan Hintz]

Greg,

That's a bit strong for regular anodized... try something closer to 25P. The only anodizing that strong of power should be used for (and in this case it makes sense) would be Type III, which is usually used on high-wear surfaces. Still, from the photo, it sure looks a lot like rattle can spray paint over cheap pot metal...

[Greg Bednar]

cheap pot metal...

Thanks Dan - and I would have never thought about the cheap pot metal being on a firearm of this caliber. (no pub intended - no really, no pun intended) It could be!

[Robert Walters]

Whatever that is, it's casted. I can see the mold ejection marks.
I've never seen casted pot metal, but I guess there is always a first.

[Dan Hintz]

I've never seen casted pot metal, but I guess there is always a first.
It's a generic term... if it's cast and hasn't been smoothed, it's pot metal. It may actually be iron, but it's easiest to call it PM...

[Mike Null]

Pot metal that I am familiar with is a low melting point metal or combination of metals which exclude iron.

It's quite common and has many applications. It is not likely to have been used on guns.