Removing dye from bone or redyeing?

I tried another experiment today to check for dye penetration.
I used 600 grit abrasive paper to simulate wear on the magnum bonsai canoe.
It took quite a while to get through, but I did eventually get a hint of red showing through.
The area that I sanded was a lot shinier than the other side of the handle, and there was dust from the sanding, so I must have simulated quite a lot of wear.

This tells us a couple of things:
1. The dye did not penetrate as deep as the original red dye.
2. Even so, it would probably still take years of pocket carry to wear off enough bone to spoil the dyed finish
3. I probably didn't simmer the knife for long enough.

I simmered this knife in the dye for 15 minutes. Further reading about dyeing suggests that half an hour is the minimum, so a longer treatment would almost certainly make the dye penetrate deeper.

Even if we can't get better penetration than this, it's still not bad. The dye is definitely not just sitting on the surface.
At the very worst, a heavily-carried knife will need redyeing every couple of years.
I expect a longer bath will do an even better job, but unfortunately I'll have to wait until I get more knives to experiment on.
 
Wow, this is a really cool and informative thread. Is there any chance that the brief time in boiling water could mess up the heat treatment of the metal? Do you think the dye would also tint the enamel on the interior of one of Case's colorful shields?

I'm getting ideas here...
 
Boiling water at 212 degrees will have zero affect on the temper. I do wonder how it would affect any glue or epoxy holding on shields, scales, etc. though.
 
Flying Guillotine said:
Wow, this is a really cool and informative thread. Is there any chance that the brief time in boiling water could mess up the heat treatment of the metal? Do you think the dye would also tint the enamel on the interior of one of Case's colorful shields?

I'm getting ideas here...
Click to expand...

As Blue Sky rightly pointed out, the boiling will not have any effect whatsoever on the heat treat.
The point about epoxy is a good one though, the usual way to remove epoxy is by boiling in water!
I have tried to pry out the shields on the knives, and they don't seem to have been affected, even one that I superglued in after it fell out a while ago.
I guess they don't use epoxy to attach the shields, but it is a very valid point and something to watch out for.

As to the enamel, if it is actually enamel, it is basically glass, so I can't see how it would be affected as long as the knife wasn't heated/cooled too fast.

I'd drop the knife in another pot with plain water, gradually bring it to a simmer, and then transfer it into the simmering dye. Once the dyeing had finished, I'd transfer it back into the simmering plain water and let it cool down naturally.
This would probably be best practice for all knives anyway, because it would decrease the chance of bone cracking through thermal shock.
There's always going to be an element of risk, but I don't think it's a big one.

If the enamel is fake, all bets are off.
The easiest way to tell is to hold the enamel against your tooth and move it slightly. If it is real enamel, it will feel hard, if it is plastic, resin etc, it will feel soft.


In other news, penetration may be better than I thought.
My RR barlow broke!
I took it out of my pocket, and the backspring on the small blade went 'ping' and part of it flew off :(
Nothing to do with the dyeing process of course. I don't blame rough rider either, these things happen, and from a google search for 'broken backspring', seems to happen most often on Queen knives. Couldn't find any references to a rough rider backspring breaking, so I guess it's an isolated incident.

Anyway, I have dismantled the knife, hoping to reassemble it without the small blade, to make it into a single blade barlow. It's been interesting so far, and I'm enjoying learning about how these things are put together.

In the process of dismantling the knife, I removed the scales.
The scales were held on by some kind of rubber cement, presumably just to hold them together during assembly until they were pinned.
I noticed two important things:

The inside surfaces of the scales were black.

The inside surfaces under the adhesive were black.

The first could be explained away by dye seeping under the scales while the knife was submerged, but the second one not so much.
The adhesive was still very thoroughly stuck to the scale, and I had to use a razor blade to scrape it off. The adhesive itself was not dyed black, it was red in color.
This seems to me like the dye must have penetrated very deep, through the thickness of the scale in fact.
When I sanded the canoe as explained above, I got through to red, but it is very dark red, not like it was before I dyed it black.
I think they dye penetrates pretty deeply, but is only absolutely jet black for a certain thickness.

Hopefully, this is very good news. It tells us (I think) that they dye is getting very deep into the bone, but needs to be simmered for longer to get good color saturation.
 
Ok, I have bad news and good news.

The bad news is that I was attempting to repair my barlow by making it into a single blade, and I messed it up :(
I finished the handle rivets, and for some stupid reason, decided to give one of the rivets one last smack with the hammer to ensure that it was set properly.
Obviously, the scale shattered and bits flew everywhere.
I wish life had an 'undo' button sometimes :mad:

The good news is that I'm happy to report that on this particular knife, the dye had completely penetrated the scale.
The scales weren't 100% black to begin with on this one. The scales were amber bone, and after dyeing, they looked black until I looked at them in strong sunlight, when it became apparent that they were extremely dark brown.
This almost-black-brown had permeated through the entire cross section of the scale that I cracked, showing that the dye must have penetrated fully. The original color was a very light amber color, like caramel, so there is no question as to whether the dye made it through.

On the subject of the canoe that I sanded, I believe that if I were to be stupid enough to crack one of it's scales, I would see an extremely dark almost-black red.
I thought at first that the red color I saw when I sanded the top layer off would get lighter and lighter if I sanded deeper, but now I'm not so sure. I think that the dye did in fact penetrate all the way, but was not dark enough to completely swamp the original red dye.

Considering I now know that the 15 minute simmering time wasn't enough, I'm pretty confident that I can get complete penetration of 100% black by simmering for longer.
All of the info I have read on dyeing tells me that the more concentrated they dye, the darker the end result, so now I'm going to revise my formula:

Enough water to cover the knife
Two packs of dye
Simmer for a minimum of half an hour

I'm aiming for complete penetration, but I'll be happy if the dye penetrates as far as the factory dye, which I doubt will be a problem.
 
awesome thread! wonder if you could dye a yeller delrin sodbuster:eek::D
maybe i'll take the hit and buy myself another one and experiment, my wife will buy that excuse i'm sure;)
cool thread though, ive tried with limited success the leather dye, stain etc. but i was looking for a richer more varied look rather than a uniform color.
thanks
gene
 
jamesbeat said:
Just to throw something else into the mix, Tintex, Rit etc make a 'color remover'.
I looked up the ingredients, and it's not a bleach.
It works by turning insoluble dyes into water soluble metal salts, ie it will dissolve and carry away any dye it comes into contact with.
Treatment is similar to the dyeing method, simmer for a while in the solution.

I expect it's too much to ask for it to completely remove all dye from a piece of bone (though not beyond the realm of possibility) but even if it simply faded the dye, it could open up a lot of new color options when dyeing.

From what I gather, it also better prepares the material to be dyed, so it might make a good pre-dye treatment for bone too.

I'll pick some up and give it a go once I get some more knives to experiment on.

The only drawback to this thing is that I no longer have any 'beater' knives to experiment on.
Now I have discovered how to dye bone, I simply do not posses any knives I don't like :D
Click to expand...

I bought the Rit Color Remover (powder) when I bought the Navy Blue dye for use on my Small Texas Jack. I used 1/2 the package in boiling water as a pre-treatment before dying the STJ. I was impatient and only boiled it for about 5 minutes and have no idea if it helped any. I had previously done quite a bit of "experimenting" on the scales of that knife so I don't think it would qualify as a representative sample for arriving at any conclusions. :rolleyes:

Fast forward to yesterday ..... I had recently purchased a Case Pocket Hunter knife in red bone. Now I don't hate red bone or anything, but after reading the above quoted post I decided to use the last half of the Color Remover on it and see what it would do. This time I boiled it for half an hour. It stunk up the kitchen bad ..... I mean bad that it probably isn't healthy to breathe. I'm absolutely no chemist by any stretch of the imagination; for those of you that are, the package lists Sodium Hydrosulfite and Sodium Carbonate Anhydrous as ingredients. I opened all the doors and windows and turned on fans to exhaust the odor and left the room.

(Note to self (and others): Do NOT use during the wintertime or any other time that you're not prepared to open every freaking window and door in the house! The exhaust fan above the stove alone would not cut it!)

Sorry to ramble - - on to the results! It didn't completely remove the existing red dye at all. The scales are still mostly (somewhat faded) red and it left a chalky appearance on the scales. I tried scrubbing this chalkiness off and it didn't come off. It "disappears" when the scales are wet, yet quickly reappears when the scales dry off. It's like the bone is extremely dry. It probably has prepared the bone quite well for accepting new dye.

Since jamesbeat has successfully dyed multiple knives without this Color Remover, and since it produces an unpleasant, not to mention probably unhealthy, odor I don't think I'll use it again. If it would have removed all color from the scales, so you could dye the knife a lighter color, then it may have been worthwhile to use in those instances.

Edited to add pics:
colrem1.jpgcolrem2.jpg
 
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That chalkiness is very interesting.
Remember I mentioned above that I had dyed a dog bone to check penetration?
Well that bone was chalky too, and it sucked up the dye like there was no tomorrow. I guess it is a good prep for dyeing, but the bone would need to be treated afterwards to make it less porous, with a wax or oil presumably.
 
Just a small update, I checked the melting point of Delrin, and also the temperature at which it starts to soften.
Both were way above the boiling point of water, so I gave it a go on an old scout knife.
It worked perfectly, but I gave the knife away without taking photos, for which I apologise.

I also tried dyeing a vic classic, but unfortunately, the plastic scales distorted horribly, so DO NOT ATTEMPT TO DYE VICTORINOX KNIVES!
Luckily, the classic was a junker with a broken blade, so I didn't spoil a good knife.

I have some new knives on order, and they are due for delivery tomorrow.
Unfortunately, I have some extremely important business to take care of over the next week or so, so the photos will have to wait.
 
Interesting, so apparently some of them used a very low temperature polymer for the scales... Well, like always, don't start screwing with something that you couldn't live without if it screws up!
 
Yup, I would have thought Victorinox would have used Delrin, since from what I've read about it, it has properties that make it very suitable for knife scales.
The plastic didn't melt as such, it just softened to the extent that it became horribly distorted and crawled off the knife.
I've accidentally got solvents on vic handles before, and it attacked the plastic. I'm guessing maybe it's just ABS or something similar.
 
I had my Swiss Army Knife in my back pocket with small bottle of Deet based mosquito repellent. I didn't put the bottle cap on super hard and a tiny amount leaked out and some got on the knife. To my surprise the handles on the Swiss Army Knife were partially dissolved. Word of warning to campers: Solvents and Swiss Army knife handles do not mix. Well, actually they do mix. That's kind of my point.
 
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