Update, M4 and Apples.

[gull wing]

You will recall I posted several weeks ago on this matter.......found a blob of "goo" on my Gayle Bradley. Of course it came from slicing apples. See pic:


I didn't want to patina my GB, but felt it was the only way to keep using it. I really want to keep using my Gayle Bradley. I think I've found a way to be comfortable using it, without worring about messing it up.
First a bath in lemon juce.


Then rub it down with Scothbrite.




This works well for me.:D
The look is better than my poor photos.
The CPMM4 is a great steel I love it.

[maa14]

Looks good... How long did it sit in the lemon juice?

[SolidState]

That's how I do mine too. It looks great!

[phaust]

I like how the bug logo and surrounding area came out. It almost looks like you traced it on with charcoal.

[jackknifeh]

That looks great.

There are two threads you know?

Jack

[razorsharp]

Would be sick with a stone wash after the lemon bath! Id do this to my caly but im forming the patina naturally

[Ferris Wheels]

That turned out great, very nice work. I would also like to know how long you left it in the lemon juice.

[SolidState]

I generally leave mine in overnight. Usually, the blade doesn't look like it's been etched until you pull it out. It has a strange metallic smell, and turns black as soon as you pull it out into the oxygenated air. I guess you could blow bubbles into the lemon juice to achieve some of the same effect, but I like seeing it. Generally, I leave mine in a glass of diluted lemon juice, about half and half.

I've also done it with dilute phosphoric acid to similar effects on steel cutting tools.

[Left Hand Path]

Great looking patina. I have never tried lemon juice, but have used white vinegar on traditional knives. Looks like lemon juice is a good option.

[gull wing]

Thanks!

I have lemon trees, so.......full strength :D . Overnight.
Note: Stand blade up, as in a slim glass, etc, you get even "action" that way. Pull out, rinse in cold water, let it dry. Pull or push Scotchbrite in one direction, rinse often to see what you are doing, I use alcohol, dries fast.

Stonewash may allow for more oxidation/rust, afterall it's exposed metal. Stonewash, Not on M4.

Now lets have more CPM M4 Spydercos. :cool: How about a Sage1.

[Cheddarnut]

Does anyone know if cpm D2 would take a similar patina?

[Left Hand Path]

Does anyone know if cpm D2 would take a similar patina?

I don't know if it would take a forced patina or not, but in my experience CPM-D2 is extremely stain-resistant. More so than regular D2. It would be an interesting experiment.

[kbuzbee]

Does anyone know if cpm D2 would take a similar patina?

It does. My Para came out grey with some very pretty rainbow effects. My Mili OTOH came out jet black, just like my M4 Air. Can't really tell you why the difference (but I have a couple theories)



You can't see the rainbow effect in that shot. It's hard to capture.

Ken

[juneau92]

Nice! I'm going to the store to buy some lemon juice. First, I need someone to detail what I need to know to remove the blade from my GB. Also, Please detail for me how to re-install the blade. I'm new at this. Thanks!

PS - After a soak in lemon juice, and then scrub with Scotchbright, will this protect the blade from rust, apple slicing, etc. Or is it just for fun and looks? Thanks guys.

[jackknifeh]

Nice! I'm going to the store to buy some lemon juice. First, I need someone to detail what I need to know to remove the blade from my GB. Also, Please detail for me how to re-install the blade. I'm new at this. Thanks!

PS - After a soak in lemon juice, and then scrub with Scotchbright, will this protect the blade from rust, apple slicing, etc. Or is it just for fun and looks? Thanks guys.

If you are any good at all with your hands and tools just take the gb apart. You won't be "removing the blade". I think you should disassemble the entire knife. Makes putting the blade back in much easier. Of course, go slow and pay attention but it's one of the easiest types of knives to disassemble and reassemble there is. And I'm not real experienced. One tip to reassemble and it's not a big deal. After you get the bottom scale and liner lined up, put the pivot pin in place and use the pivot screw to hold it there. That way it won't fall off if you move the knife around as you re-assemble it. As you reassemble it put a drop of oil in the key spots to ensure coverage. That means between each washer and the blade and around the pivot pin. Then put the top liner and scale on. Never tighten a screw all the way until all the screws are in place. That's normal for about any assembly.

I'm sure there are videos of assembling liner locks on you tube. I used a YT video to guide me throught the re-assembly of a Manix2 which is more difficult IMO.

A patina is a form of corrosion itself but will protect from the bad corrosion, RUST. That's my entire understanding and why I wanted a patina on my GB blade. I also take it apart a couple times a year to treat the tang with Tuf-Glide and clean it out. The washers on the GB are about the thickness of a Tuf-Cloth because the TC fits between the liner and blade when the knife is assembled which is nice.

Good luck but the liner lock knives I've taken apart all went back together perfectly. Of course they fall apart 30 minutes later. Kidding. :)

Jack

[Blerv]

I would die for a Chaparral in M4. That said, the new GB Air is only 2.3mm thick. :D

Thanks for sharing Gull...looks great!

[NoFair]

Does anyone know if cpm D2 would take a similar patina?

It does stain a bit from some acids. Put a patina on mine after rhubarb juice causing some corrosion. (used warm whine vinegar)



Looks almost the same now years later

[juneau92]

If you are any good at all with your hands and tools just take the gb apart. You won't be "removing the blade". I think you should disassemble the entire knife. Makes putting the blade back in much easier. Of course, go slow and pay attention but it's one of the easiest types of knives to disassemble and reassemble there is. And I'm not real experienced. One tip to reassemble and it's not a big deal. After you get the bottom scale and liner lined up, put the pivot pin in place and use the pivot screw to hold it there. That way it won't fall off if you move the knife around as you re-assemble it. As you reassemble it put a drop of oil in the key spots to ensure coverage. That means between each washer and the blade and around the pivot pin. Then put the top liner and scale on. Never tighten a screw all the way until all the screws are in place. That's normal for about any assembly.

I'm sure there are videos of assembling liner locks on you tube. I used a YT video to guide me throught the re-assembly of a Manix2 which is more difficult IMO.

A patina is a form of corrosion itself but will protect from the bad corrosion, RUST. That's my entire understanding and why I wanted a patina on my GB blade. I also take it apart a couple times a year to treat the tang with Tuf-Glide and clean it out. The washers on the GB are about the thickness of a Tuf-Cloth because the TC fits between the liner and blade when the knife is assembled which is nice.

Good luck but the liner lock knives I've taken apart all went back together perfectly. Of course they fall apart 30 minutes later. Kidding. :)

Jack

That is very helpful information. Thanks very much! I have a GB and also the blue M390 Para 2 (brade new) so far. Love these knives!

Alan

[phillipsted]

I had to go refresh my basic chemistry knowledge to understand the difference between red rust (ferrous oxide) and black rust (ferrous ferrite or magnetite). The following web page has a pretty cool description of the process:

http://mgaguru.com/mgtech/restore/rt106.htm

From this description, black rust is chemically stable and will not, by itself, cause any more corrosion of the steel. However, the coating is relatively thin and wears off easily. If you do patina your blade, you'll still need to keep it coated with oil to control further corrosion.

TedP

[Evil D]

I really like how that turned out, i like it a lot before you brushed it. That was the look i was going for with my last Para 2 when i tried to acid etch it. Then i planned on letting use and wear mark the blade as it happened and leave it that way. I would love to have a M4 Military.