XCR Forum banner
1 - 8 of 8 Posts

· Registered
73 Posts
Discussion Starter · #1 ·
I was bored, so I thought I'd show a little bit of what I do everyday (of some variation of).

I had a customer bring in yet another Sig Sauer P6 (P225, 9mmx19 single-stack). They keep coming in.....I have probably done a hundred Sig P6's since the big import boom started.

This particular pistol had a nice black barrel, but the rest of the parts were like most of the ones I get in - cruddy and worn.
Alot of the refinishers or home-hobbiests I run into normally just clean the gun up and overspray the visible parts with DuraCoat or some type of binary finish.

That stuff really is good, because it can make a bad looking firearm look new with little effort....at least from the outside.

We offer special refinish packages for several different types of firearms, but they are more of an "overhaul" than a simple refinish job. This is what is being performed here:

We first receive the gun, log it in, then start taking it apart. Everything gets disassembled. Every roll pin, every part. We are done when each piece is down to its basic machined state.

It's important to know exactly what you're working with when dealing with a certain type of firearm in for refinishing. You don't want to mistakenly drop a 6061 T6 aluminum receiver into a 300 degree bluing bath. Bad things happen. For the P6, it was easy, because we have worked on so many. But for stuff unfamiliar to you, it's a good idea to do some research to find what types of metals/alloys you have.

After checking all the parts for serviceability, into one of our small benchtop ultrasonic cleaners they go! I am generally too lazy or under serious time constraints for manually wiping down and cleaning the parts. A good ultrasonic is worth its weight in gold to the hobbiest and professional alike. They are also INVALUABLE for cleaning closed parts, like silencers.

4 minutes @ 80deg C, and we are ready for a cold water rinse to wash off the ultrasonic detergent.

Here are the parts we are going to refinish. Note that I only have the ferrous (carbon steel) parts set aside, as the customer has requested phosphating.

The P6 frame is Type III anodized at manufacture. Anodizing has two purposes: 1) Increase the structural integrity of the part 2) Allow for dying of the part for color. Anodizing in its simplest form is clear, or rather nearly impossible to see. It is not until dying and sealing that you can actually "see" the effects of the anodized layer. We have a 49 Gallon Type III Hard Coat line. I can do around 15 AR-type receivers at a time, limiting factor being my power supply. Processing time on the line runs about 2.2 hours, from alkaline cleaning to sealing of the part.

The Anodizing Tank. Titanium coil in the back is for the chiller. Bath must be kept cold to anodize parts to Type III specifications. The aluminum bars on the left and right are the cathodes, and the bus bar in the center is positively charged, and the part is suspended in the sulfuric acid, and becomes the anode. Not shown is the air sparger, which forces large air bubbles through the solution to aid in agitation/stirring. I think we had them out for cleaning.

Unless specifically requested, I try not to re-anodize a part more than once. Reanodizing further erodes the alloy surface, opening up tolerances and shrinking the surface area of the part.

Type III anodizing, when parts are processed properly, can last a VERY long time and is highly resistance to wear. This anodizing job still looks good after over 20 years, with only minor wear on spots with constant contact (decocking lever, slide rails). Customer has requested DuraCoat, so we will coat over the clean, dry anodized layer.

Time for some surface prep on our small parts. 90% of refinishing is surface preparation. Surface needs to be clean and devoid of any oils, carbon, or debris. Even though we are about to blast, I am going to blow the cleaned parts dry with the airgun. We want to minimize the amount of moisture in the blast cabinet. Moisture + aluminum oxide = :mad:

Parts dried, ready for blasting.

Parts all blasted with aluminum oxide, in the white.

Time to rinse the parts to clean off the alumox dust, and rack them for phosphating/parkerizing.

Some very economical and simple racking techniques. Black iron wire is your friend.

We always try to rack the parts in inconspicuous areas. Sometimes the part will not parkerize where the wire touches it. Some light agitation can remedy this, but is a good practice nonetheless. This is especially true with electrochemical processes like anodizing.

Our bath temp is about where it needs to be, so it's time to cook the parts. I had just got done making up a new park bath, as my old one was dead. Takes about an hour to prep the bath for use. Some iron powder in coffee filters "seasons" the bath.

P6 slide, and the phosphoric acid reacting with it.

After about 5 minutes (or until the part stops gassing), we take it out.

We need to rinse this part quickly. The flock (phosphate sludge/buildup) will fuse itself onto the part if allowed to dry. It becomes very hard to remove.

We rinse that part, then air blow it dry. Repeat with other small parts.

Here is the result of the slide and parts. There is a bit of light flock buildup on the slide serrations, but it will brush off. The phosphate layer is now clean and dry, but is chalky in appearance.

Finally, we want to coat these part with water displacing oil. The oil will penetrate into the pourous phosphate layer. It will darken it, add some lubrication, and help protect against corrosion. I forgot to take pictures of this step.

My XCR has about 8k rounds down the pipe. All things considered, the finish on the bolt/carrier/piston have held up enough, but I figured I'd do these parts right quick so you could see what a park job looks like after the lubricating oil.

Gotta remove the piston head and weights. (Elastomeric vise jaw pads are TEH WIN!!, make things much simpler.)

Piston/carrier in the white after blasting.

Finished products.

Good color match with freshly anodized XCR receiver. This is the one I posted awhile back that I camoed. I got tired of it and decided to go back to black. ;D

Will try to post some finished pictures of the pistol. It was late when I left, and still need to DuraCoat the frame per customer's request.

· Registered
6,835 Posts
Looks real interesting. I need to come by and visit when I get back from the sandbox. I would love to see it all done in person. Maybe I will bring a P6 of my own for you to do.

Do you do much anodizing in colors? I am having a deployment M4 built that will be anodized FDE, the first sample lower should be done sometime in the next few weeks.

· Registered
3,296 Posts

Interesting to see how you guys work your magic.


· Registered
73 Posts
Discussion Starter · #8 ·
Naughty! Don't vise the op rod like that! :eek:

The pads conform around it and are sticky. It's like a toned down version of a little miniature vice block, for about anything I put in it.

I hardly have to torque on the vise at all to keep it from moving.

Don't worry, I won't crush/deform it ;D
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.