Did you order a Raw 80% or one that had been anodized already? How did you prep the part for either the raw 80 or the anodized 80

I've used MolyResin on two or three 100% A2 receivers back in the day.

So spraying an anodized lower you just need to degrease or and spray.  The MolyResin will stick just fine.

I've never used it on bare aluminum before so l really can't help you there.  I imagine you'll have to rough it up, via blasting,  somehow though.

Thank you!

So I am going to update my thread. I wrote John Norrell an email and he responded a few hours later. How is that for customer service? He took the time to write the following back to me. I will copy and paste it here.

Here were my questions:

1. When applying Moly Resin to an already anodized lower do I need to media blast that part first? If so, how aggressive does that need to be? I have never done this so hopefully that question makes sense.

2. When buying an 80% lower would you recommend a raw one or one that has been anodized? What would be the process to apply the resin to a raw aluminum lower?

I plan on using aluminum oxide to blast whatever parts need it.

Here is his answer:

Mike, Nice to hear from you.

If you have an absolutely perfect anodized finish to start with, you can just blast to lightly scuff it up rather than remove all the anodizing but be aware that leaving the dark original finish as your primer surface, that darkness can shade the top coating you place on the receiver. It may make the top coating look darker.  Especially if you put tan, for example, over a black anodized receiver.  The tan will not be the full tan look you may want. All of my color pigments are based on going over fully blasted metal down to the white. That also applies to a situation where you blast the lower receiver down to the metal but just scuff the upper receiver. You will likely get a shade difference in color with the scuffed one being a little darker. Same thing with accessories, in that either blast every part of the firearm down to fresh metal or just scuff all the parts. That way all the parts will look alike when you get finished with the coating and curing.

Generally, people needing to refinish have receivers that have dings, scratches, marks, slick places, ect. and blasting down to the white metal will blend out those imperfections and create the best prepped metal. Then place the coating over the fresh metal and you get the exact color of the product.

On an 80% receiver I would also prefer blasting down to fresh clean white metal for best adhesion and to create a consistent surface and also blend out the minor scratches, etc.  Blast a raw metal receiver (in the industry that is called a "receiver in the white.") just means you don't have to use extra time to blast off the anodizing and that can be time consuming.  Plus lot of companies anodize receivers that are not perfect and have some blemishes, scratches, dings, etc. that they anodize over and when you blast you can then clean up the receiver and make it look better.

Take your time and don't get too aggressive with aluminum so use lower air pressure. Use about 40-50psi for blasting aluminum as the metal is softer and the 40-50psi will not create a highly textured surface. Steel usually should be blasted at 60 to 80 psi.  Speed is your enemy in blasting or coating.  Lower psi takes longer but gives you the best appearance and spraying 6 light passes of coating is much better then trying to coat in one or two heavy passes.

Hope that helps.
John

I thought it was really great of him to take the time to hammer out an email that long.

My experience with John has also been positive.

John sent me a follow up email with a side by side picture of an original Colt XM Gray next to his Norrell’s Moly Resin Gray-Black Colt Flat.

Here they are for anyone else doing retro builds.
Attached File