Gunkote abrasion resistance -- follow up

A short while back I posted a picture of a mag that I finished with Gunkote 2404F (FDE) where the area above the catch was completely scraped off. The expert's conclusion was that the failure was because I didn't blast the mag first with aluminum oxide. I really hate it when they're right!

I bought a small blasting gun at Harbor Freight and did another mag today. The original mag (left) showed this problem after just a few insertions. The mag on the right has been inserted and ejected 50 times. The ONLY difference in the process I used was the blasting. The results speak for themselves. I would highly recommend Gunkote AND blasting first.



My thanks to the X-Spurts.

Tell me more about this blasting set up...how big of a compressor and is in a cabinet of some kind?

Thanks!

I'm using a small Porter Cable pancake compressor (because that's all I have). I bought a 1-litre blasting gun from Harbor Freight and a jug of 70-grit aluminum oxide (they didn't have anything finer). I set the pressure on the compressor to 70 pounds. Adjusting the nozzle one the gun in and out determines how much media comes out. For my mag experiment I just did the blasting in the driveway and accepted that I'd never recover the media. I plan to build a small enclosure out of blue tarps so I can hang larger parts and to catch as much as I can. Absolutely wear good goggles and a good dust mask. Regular old safety glasses won't cut it because the grit goes around the sides. That chit goes everywhere! Also, wear a heavy glove if you're going to hold the part while blasting.

I did a mag first because I could pretend it didn't matter if I screwed it up too badly. The 70 grit left a slightly textured finish, which I actually like.

http://www.harborfreight.com/1-liter-abrasive-blast-gun-92857.html

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I'm using a small Porter Cable pancake compressor (because that's all I have). I bought a 1-litre blasting gun from Harbor Freight and a jug of 70-grit aluminum oxide (they didn't have anything finer). I set the pressure on the compressor to 70 pounds. Adjusting the nozzle one the gun in and out determines how much media comes out. For my mag experiment I just did the blasting in the driveway and accepted that I'd never recover the media. I plan to build a small enclosure out of blue tarps so I can hang larger parts and to catch as much as I can. Absolutely wear good goggles and a good dust mask. Regular old safety glasses won't cut it because the grit goes around the sides. That chit goes everywhere! Also, wear a heavy glove if you're going to hold the part while blasting.

I did a mag first because I could pretend it didn't matter if I screwed it up too badly. The 70 grit left a slightly textured finish, which I actually like.

http://www.harborfreight.com/1-liter-abrasive-blast-gun-92857.html

[/quote]

with that small of compressor, was it hard/take long? I plan on doing a handgun and all i have is pancake as well. Wasnt sure if it was adequate enough. thnx

It did just fine. It didn't even run most of the time. It took about three minutes or so to do the mag, and I was going slowly to be sue I didn't over blast anything. I've never done this before. I blasted until all surfaces had an even dull finish. If I was doing large surfaces like a car door the pancake probably wouldn't handle it. I went through about 2/3 litre of media doing one mag and that would get expensive if I can't figure out how to recover it.

Doing a hand gun should be no problem.

Cool! Thanks for the tips and the link...I will probably pick one up and build some type of blasting cabinet. I have been doing some duracoating and I think it may also work better if blasted first.

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