Briley Bushings - Might I have a word

[03hemi]

When I start shooting mine, I'll be aware.

 

[BMCM]

Bill,

Great writeup. I just took apart my new to me shorty 40 and the bushing collar was actually loose and came right out. There was no adhesive or anything on the threads. The inner ring looks good. What should I put on the threads to put this back together? Is there a proper way to grab the collar when screwing it in to tighten it?

Clean everything thoroughly and wipe down with acetone.

Now, bear in mind you are NOT going to torque the bushing in tight.

After cleaning, trial fit it dry. You'll want to screw it in dry first to see where it's at when tight then back off until the cutouts for the ring are aligned across 3 and 9 o'clock. That is where it should be when installed.

Loctite 680 Retaining Compound is what you're going to need.

Give the slide & bushing one more wipe with acetone then make sure it's completely dry free of any contaminants. Coat the first couple threads in the slide with a bead of 680. Likewise on the bushing, a bead of 680 of the first couple threads. Then screw the bushing in to where you noted during the dry-fit. You want to see 680 squeezing out both inside and on the outside. You can use the nitrided ring or a nickle as a tool to screw the bushing in and tweak the alignment across 3 & 9 O'clock as needed.

When it in and aligned correctly, set it aside until tomorrow. When you come back to it take some swabs or patches, wipe up the excess 680 and put it back together, you're done.

Warning! Do Not! use any Loctite primer compound such as SF7649, it will cure the 680 before you get the bushing in all the way. Ask me how I know that

Cheers
Bill

 

[BMCM]

I think I am understanding the wiki on the PVD process (uhh..I think.)
I wonder how does the tinite adhere to the bushing?
Is it flaking off in those pictures? One article suggests that thicker coatings will flake but the thinnest coating will not.
The eggshell analogy was very interesting. It sounds like the TiN cracks under the force of the pliers and is not actually adhering to the steel?

Thank you BMCM for your kindness in teaching us!
BrianD

The TiN isn't flaking off, it's just broken. It's a very hard material applied on some relatively soft material. In general the harder a given material is the less ductile it is. In tooling such as drill bits this is illustrated by the difference between tool steel drill bits and solid carbide drill bits. You can use tool steel bit in a hand drill with no problem because they are somewhat ductile. Solid carbide tools, on the other hand, are not ductile at all. The least amount of deflection and the tool will fracture. And in accordance with Murphy's Law it'll snap off down in that hole you were drilling. Drilling with carbide bits requires solid fixturing on a mill or drill press with the work in a vise. Otherwise...Kerschnapp! followed by lots of colorful language.

TiN is extraordinarily hard wear resistant applied coating. However, being extraordinarily hard also makes it brittle. Grab the part with a pair of pliers or pry at it with some other tool and the underlying soft ductile material deflects allowing TiN coating to fracture. Adhesion is not the issue. Grabbing it with vise-grips is. And in those two cases above, the shredded TiN layer was only a small part of the issue. The more serious problem was neither of those rings were round anymore.

Cheers
Bill

 

[44wheelman]

Stressproof steel has a max hardness of Rockwell C 20 (B97). I am surprised by the softness of the substrate.

Thank you BMCM for you excellent write up!