Removing BT2

[LyonHaert]

I'm trying to remove the BT2 coating from my BM 710HS. I sanded most of it off, but I'd like to completely remove it, especially in the pivot area, where I want to polish the metal. From what I understand of Teflon-based stuff, it gets into the pores of the metal, and still protects it. That's probably what I'm seeing right now, where the grind lines are somewhat shiny, but the facets are gray, with darker areas near the grind lines.

It looks pretty cool this way, like the blade is pretty old and roughed up, but I'd still like to know a way to completely remove the BT2, preferably without removing much metal (like a chemical or something).

 

[mblanton]

The best bet would be to bead blast the surface - if you are careful you will loose very little steel.

If that is not an option, try acetone or methyl ethyl ketone. BT2 is most likely an epoxy or epoxy-phenolic coating which is highly cross-linked when cured. This is why it has such good solvent resistance. You may have to rub the surface with a soaked rag but the solvents will at least accelerate the degradation of the coating. I don't know your background in handling solvents so be careful and use under adequate ventillation. Also, methyl ethyl ketone will penetrate latex gloves under prolonged contact.

 

[underaged!]

You can ask a major autobody pain shop about acid bathing. umm, it shouldn't damage the steel, I saw on some show that the acid was supposed to remove any paint or corrosion and leave the metal untouched.

IDK if it will remove the BT though

 

[Saberman]

I removed the BT from my BM750 using flitz polish, Took some time but left the steel with a nice gray tint to it.

Removing the bt from the pivot.... I have conflicting thoughts on this.

1 The BT is Teflon Based. So it's a nice assist in the lubricating area.
2 Polished pivot should give you a smoother action.

Any thoughts?

 

[LyonHaert]

Thanks for the info, guys. I know I can find methyl ethyl ketone in PVC pipe cleaner. I might try that.

I've always had problems getting the action on the 710HS right where I want it, and my thoughts where that while the teflon is non-stick, that doesn't mean its surface is smooth. Since it isn't smooth, non-stick teflon or not, there's still going to be a certain amount of friction that would not be there if the area contacting the washer were polished.

Even without polishing it yet (used to have some sheets of fine sandpaper, can't find them), the action feels better.

I'm going to take some pictures of the finish on the blade soon, it looks pretty wicked as-is.

Edit:
While I'm at it, I should polish the washers and possibly the liners, too.

 

[Runs With Scissors]

I personally had horrible luck with MEK when I tried it on my Axis AFCK, and sanding it seemed to do more harm than good. (even tried MEK and a dremel with wire attachments.)

I finally got it right with the sandblaster here at work. less than a minute later and I was back in business. It looked pretty damn good when I was done, and definitely kinda unique. I eventually got bored with the knife and traded it off at the local knife shop, but as I recall it didn't stay on the shelf long at all.

If you don't have access to one, I'd think you could find one at a local body shop or something and pay 'em $5.00 or so to do it for ya'. (although from what the other ole boy said about the acid thing, that may be even more preferrable if it's available)

 

[LyonHaert]

Here's how the blade turned out. If I'm going to own and use this knife for years, it might as well start looking the part. The aged look gives it a lot of character, and I did the same thing to the clip. After polishing the pivot area and washers (finished on 600 grit silicone carbide paper since I didn't have anything higher grit), the action is significantly smoother, too.

Now to look into modifying/replacing the backspacer and scales.