T91 80% Lower Anodizing Problem

[JTM20]

I finally got around to sending my 80% T91 lower to be hard coat anodized. It came out great, except the center of the "rifle" character came out.

Anyone else seen something similar?

20191010_074458.jpg

[darkest2000]

It may have eroded away during the anodizing process, it can happen with type III anodizing especially if your doing one off parts rather than an entire batch of similar parts.

By the way it still came out looking great, who did you use I’d you don’t mind me asking?

[JTM20]

SNF Finishing

That's probably what happened, the lines there were very fine. Or the sand blast was too aggressive.

Either way, it looks great besides that spot. Great color match to my uppers.

[JTM20]

I finally got the lower assembled.

Unfortunately, it is very out of spec. Most was fixed by minor filing, but the mag well was so tight it wouldnt fit a single mag (PMAG's, USGI's, even an original T91 mag). I had to remove quite a bit of material to get mags to work, which ate away most of the magwell anodizing.

I'm pretty unhappy with my purchase, especially considering the price of the lowers, and encourage anyone else to test fit their lower before coating.

[darkest2000]

I just tried test fitting the mags to all 3 of my 80% lowers and will confirm that they're definitely tight. I imagine the anodized process will further augmented the resistance because the process builds up thickness.

Sounds like it'll be a good idea to sand down the inside of the magwell before sending them out to get anodized...