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Discussion Starter · #1 ·
Getting ready for the next phase of the project. Building *my* kind of P228.
 

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Discussion Starter · #6 · (Edited)
Is that the frame you stripped with the oven cleaner? Nice finish. You should try the Rustoleum Appliance Epoxy on the black parts and do the bake on. Amazing results.
Good memory! No, it’s not that one. This one got a chemical strip, light media blasting, and careful hand cleanup of a few nicks. The weird color of the hardcoat anodizing is what happens with 7075 aluminum, but it is going to get an additional finishing process.

I know the appliance epoxy works well, but I like to do these with more traditional or industrial finishes.
 

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Good memory! No, it’s not that one. This one got a chemical strip, light media blasting, and careful hand cleanup of a few nicks. The weird color of the hardcoat anodizing is what happens with 7075 aluminum, but it is going to get an additional finishing process.

I know the appliance epoxy works well, but I like to do these with more traditional or industrial finishes.
Curious . . . why remove anodizing? It's often recommended to coat over, seal frame holes if necessary to maintain critical dimensions. The anodize is a near diamond hard tough surface, while a bare aluminum base is much softer . . . I guess I don't see the advantage of stripping.

When using a chemical strip to remove the anodizing, are you sealing frame holes to maintain dimensional tolerance? Or planning to tighten up clearance with the new coating? Hard coat anodize is typically .0005" to .002" thick. That doesn't sound like much and isn't for bigger parts, but on small pins, the difference between a interference and slip fit is far less.
 

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Discussion Starter · #10 ·
Curious . . . why remove anodizing? It's often recommended to coat over, seal frame holes if necessary to maintain critical dimensions. The anodize is a near diamond hard tough surface, while a bare aluminum base is much softer . . . I guess I don't see the advantage of stripping.

When using a chemical strip to remove the anodizing, are you sealing frame holes to maintain dimensional tolerance? Or planning to tighten up clearance with the new coating? Hard coat anodize is typically .0005" to .002" thick. That doesn't sound like much and isn't for bigger parts, but on small pins, the difference between a interference and slip fit is far less.
Excellent questions.

As you can see in the attached pics (which I probably should have uploaded for the original post), this was a hard-used P228 (ignore the P229 slide). It's another ex-IDF military sidearm, and those get plenty of holster wear and knocking around. This one was no exception, you can see plenty of little nicks and burrs as well as incipient frame rail wear down to the goldish color.

With one "original patina" restoration already in the cabinet, I decided to go the opposite direction with this one and restore it to better-than-new. Not interested in just slapping a coat of paint on an old gun.

Stripped it, hand worked all the nicks and scrapes away, and worked with the anodizer to get precisely the same thickness and dimensional integrity as an untouched frame. Measuring and test-fitting everything so far has been a perfect fit.

This is not the final finish; it's getting an additional process which should be dimensionally insignificant yet quite durable and attractive... that's the next step for all of these parts.
 

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Discussion Starter · #11 ·
Pics of the frame after cleaning up the scrapes and marks. This is anodized only, no cover-up with cerakote.
 

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Discussion Starter · #12 ·
So is this a purchased P228, then stripped down to build your own or was this kit put based from a site?
This is a collection of orphaned parts; frame only from one source, slide from another, all the controls purchased either as used vintage or new upgrades.

A clever eye will be able to see the modern bits in the parts layout pic.
 

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Quote:

"Stripped it, hand worked all the nicks and scrapes away, and worked with the anodizer to get precisely the same thickness and dimensional integrity as an untouched frame. Measuring and test-fitting everything so far has been a perfect fit."

RL,

Not meaning to be argumentative. And there's room for error in my comments as I'm not an expert. There's some in the above that I suspect is not practically doable. I have a small anodizing set up in my machine shop, and I anodize small parts, I'm no pro but I am somewhat conversant.

Anodizing is a controlled "corrosion" or oxidation process that in this case is changing a "layer" of the parent metal into a thicker layer of aluminum oxide which is "grown" from the parent metal. As the anodize layer grows it is "consuming" a thin layer of the underlying aluminum/alloy. The original item, at least the parent metal part, shrinks. You'd never know it though, as the product oxide layer is greater in thickness than the layer of metal that made it. Thus the finished item increases in dimension or size (though holes get smaller as the oxide grows "into" them). Mfg.'s. plan for all of this - life is good.

Problem: When someone comes along later and strips the anodize layer, the item is now smaller than before it was anodized the first time around. No problem, how about we just anodize it longer and thicker and grow it back! Nope, that probably won't work out all that well, especially if the first time has "hard anodized" (read thicker more durable). There are practical technical limits to how think the anodize can be.

SIG doesn't refinish frames and won't re-anodize for good reason. Of course it's doable as you've shown, but seriously, I can't see any real benefit in strip/anodize if you are going to recoat with another process anyway. Better to fix the boo-boos to your beat up anodized frame, even if some parts are bare and other's retain anodize. Then simply etch the bare metal (dilute phosphoric acid), seal all the holes so you don't mess it up, and coat with your favorite ceramic, epoxy, or rattle can paint - (ok, rattle can would be the last choice, but people do it and if they are happy it's good enough for them).
 

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Discussion Starter · #15 ·
Not meaning to be argumentative. And there's room for error in my comments as I'm not an expert. There's some in the above that I suspect is not practically doable. I have a small anodizing set up in my machine shop, and I anodize small parts, I'm no pro but I am somewhat conversant.
Your points are well-taken and understandably of concern.

The potential for dimensionality changes was discussed at great length before this process was undertaken with the anodizing facility. Let me first present them as something a bit more than a typical home tank setup or cosmetic refinisher; they are part of a manufacturing facility that does milspec components and other high-precision commercial items where dimensionality and tolerances are critical and beyond what is of common concern.

The hardcoat anodizing itself is between .0005" and 0.0025" thick with precision control of the final result. The goal with refinishing this frame was to match the dimensions of a brand-new P229 used for reference, and also taking into account the final finishing step which has not yet been completed. I will show and discuss that more when it is done within the next week or two.

Fundamental tolerance in a P228/P229 frame is relatively loose compared to a lot of the precision machining that I am used to, the few critically close dimensions are seen parts like the various hammer contact surfaces and sear, barrel feed ramp and locking areas.

There are very few points in the frame that have what I would consider close tolerances that would be affected by the dimensional changes of a surface finish; if you think about it, those few areas are around the locking insert (tight is normal), the takedown lever hole, the firing pin hole, the hammer pin, and the sear pin. Even the area where the sear, safety lever, and ejector resides is fairly loose (you can wiggle the ejector with your finger). SIG frame rails have a surprising amount of looseness which can be experienced as the typical rattle when the pistol is shaken (which is fine because it's not critical for accuracy, barrel is held by other means).

I would imagine that SIG does not offer complete re-anodizing due to the effort involved and the labor-intensive nature of the critical control. It's simply not feasible, especially that most frames that are at that point are likely not worth much due to their condition. That's my speculation only, of course.

Your suggestion of addressing the cosmetics of dings and scrapes while leaving the anodizing in place is quite valid, if one were to continue to refinishing process by the methods you suggested of cerakote or other topical coating. Topical coatings are easy and fine for most intended results, but not to my personal taste. I'm not looking to "bondo and spray" this frame like a used car with a ding in the fender; this is a proper restoration with techniques and finishes to exceed factory spec.

At this point, what I have *not* made clear is the final finish. The frame, and all of the parts shown in the original pics, will benefit from a protective anti-friction coating.

BTW, bumper, I am still enjoying those P-shims that I got from you awhile ago. Thanks again!
 

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Discussion Starter · #17 ·
Stages of frame refinishing progress so far:
 

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Your very welcome on those parts that shall have no name here :c)

I've sold a lot of little parts for the Classic P that to depend on tolerance for fit - I've had to replace a few with a different size due to SIG's varying frame tolerances. So most definitely concur with your observation build tolerances in the frames can vary a few thousandths . . . at least in areas that wouldn't normally affect function like side frame wall thickness etc.

When I made higher lift safety levers to insure proper function of the firing pin block safety (when adding both SRT and a trigger over-travel stop on a couple of older P229's), I made the safety levers out of thicker sheet steel to take out the lateral play in the ejector-sear-safety lever "sandwich" on the sear pin. Removing play there helps keep trigger feel consistent.

(I don't offer the safety lever for sale.)

Nice work on the rebuilds!!
 

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Fascinating work, thanks for sharing. Far exceeds the reach and grasp of me and many others, but it's fun to learn about the processes and the science/engineering behind it all.

Please do keep us all posted.

For every one like me who pipes up, I'll be there are 10+ lurkers just as interested as I am.

Really great stuff!
 
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