Filling Pitted Round Knife with Epoxy for refurbishing

[chuck123wapati]

35 minutes ago, Bant said:

 

"if the cost of going that direction is affordable"  that's the rub, new ones are only 70 bucks so how much does a guy want to spend?

[Frodo]

Joe,   Do you have gun shows in your area or close to your area?

do a goggle search for gun shows and locations.

Most, not all, gun shows will have a guy set up that sells hand made knives and usually he can sharpen and clean  while you wait. Take your knife to him, let him sand the pits out, and put a sharp edge on it.

after he is finished the only thing you should have to do is strop it when needed

cost in my area would be around $20.00  

[AlamoJoe2002]

Gents, you have provided a ton of information. If the knife arrives today I will present a few pictures of the subject.

I am not a knife maker and never forged anything in my life except my bond with my wife. Hah! And I'm finding I don't know squat! However, I have learned not to spend too much time on my hobby interests as that also gets me in trouble. I'll probably need a few counselling sessions by the time I'm done with this round knife...if you know what I mean...

Joe

 

[AlamoJoe2002]

The knife just arrived via US Post. I did a quick touch up cleaning with xylene, a brass brush, a green scrub pad and a bit of wet 2000 grit sandpaper. The blade is solidly set  into the handle. No movement. However, the blade is leaning toward the side with the Osborne mark. I will have to be very gentle with alingmnent. I will do this after sharpening.

Now some choices...I might just try to use the electrolysis to clean out the makers mark....the star is very faint.

I think I will forget about filling in the pits...

The edge is as dull and pitted when I run my finger nail along it. Public Service Message: Don't go hunting with a dull spear...it's pointless (Your turn.).

Here are the pics. I hope they load as I resized them to 364 pixels in width.

 

[Mulesaw]

If you are going to do the electrolysis, I think you need to be careful not to let the brass part of the handle touch the water/soda solution. I think it might damage the brass before removing any rust.

[Daffy]

might be worth a shot.

[AlamoJoe2002]

I made a quick electrolysis tank using an old laptop power source that converts 120 volt AC to 12 Volt DC @ 3 amps. I used a multi-meter to determine the negative and positive wires. 

I used a clear tub and zip-tied a few rebar cutoffs that I hit with a grinder to provide a clean conductive surface. The blade is hung using coated wire to where just the blade is submerged. I hooked up two alligator clips to the immersed blade which is the negative anode and the rebar is tied together in series as the positive cathode.

The idea is to surround the blade with the cathodes as the current travels only line of sight.

The solution is distilled water from my dehumidifier and Arm and Hammer Washing Soda (Sodium Carbonate) to increase conductivity. I don't know if tap water and a higher amp power source would work just as well.

I am going to leave the blade in solution at the low current overnight. One of the good things about electrolysis is that new metal will not react...so only the oxidized metal / rust will be affected. The pitting will remain...but will be free of rust. 

I'm interested in seeing how the Osborne Makers Mark turns out. The key will be if the star is more visible under the stamp. Will it be more legible or will it fade away with the rust?

This is the first time I have used electrolysis. I don't know much about metal...but if this lowers my sanding time on the blade I will be happy.

I uploaded a few about 11 images. However, I may have screwed them up getting them into this forum. I resized at 364 pixels...I think at that size they have no detail. What do you resize your pictures for uploading to this forum?

Tomorrow I will pull the blade out of solution, dry it off, and maybe put it in an oven around 180 degrees f to dry out the handle. Oh, part of the brass is in solution. Don't know how that will affect anything.

Joe

 

[dikman]

With electrolysis a high current will, of course, work quicker but the general recommendation is to use a lower current over a longer time (less than 1 amp). You can also use plain salt as the electrolyte but this will generate hydrogen so only do it outside. Probably the safest way, if you don't want to risk affecting other metal, is to use something like Evapo-rust. It's relatively harmless and will only attack the rust.

If the pitting extends to the cutting edge there's really not much you can do about it, just sharpen it as best you can. You should end up with a tool with a bit of character.

[Mulesaw]

That looks like a good setup. I haven't thought about using an old PC power supply, but I think that I'll copy your idea on that one instead of using the large battery charger at home.

As I have understood it,  using sodium carbonate and regular steel/iron as a cathode, will be the safest method. the gas emitted is CO2, and the end solution will be something that you can use to spread on your lawn, and it will help against moss growing, I think you can buy iron vitriol (might not be the correct name in English), in gardening centers, and that is what will eventually be in the tank.

Some people use stainless steel as a cathode, but then you'll get a bit of chromium in the solution which supposedly isn't quite as good for the environment.

[AlamoJoe2002]

The blade has been in solution under 3 amp DC Power for 12 hours. I checked it this morning. I pulled it out and wiped it off. I was expecting a black residue to cover the white cotton cloth. Not much...so back into the solution and power it up.

I know the process is working as I observe a reaction on the full surface of the blade and around the ground down areas of the rebar. 

I'm taking this low on power and long on time. Another 12 hours and I will check it again. If it continues to have a very slow reaction as I have observed I will keep the blade on electrolysis. I don't think I can hurt the blade. However, I am concerned about the water content of the wood under the ferrule. 

I am thinking about the re-profiling the side of the blade where it chipped. So the question is how would you improve a standard round blade if it chipped a point?

Joe