Filling Pitted Round Knife with Epoxy for refurbishing

[AlamoJoe2002]

Thanks Bruce. You have got me thinking...may be I need a new specimen to spend my time on. I truly am looking forward to learn how to properly sharpen and use a round knife.

The blade is still in the electrolysis bath. The pitting is still bubbling the rust away. It has been 24 hours and I don't see much of an improvement to the blade material. I will keep up the process and see how long it takes in solution for the reaction to stop.

So in the mean time I am now on the look out for a round knife to clean up, sharpen , and make it mine. Right now I paid $26 US for the knife. I will begin the hunt for a new specimen. I feel honored to have Bruce weigh in on this project. If anyone has a vintage round knife they would like to pass along at a reasonable price please send a PM. I say vintage because the train of thought is the newer manufactured knives on the market are produced with lesser quality steel.

JOE

Joe

[dikman]

For only $26 I think it's worth persevering with it! I'm sure you will end up with a usable blade. As for your last statement I understand where you're coming from but it's not necessarily the case, it will depend on the manufacturer. The older blades would have been plain carbon steel (hence the rust) but there are many steels available these days that are better, with greater edge-holding and toughness. Personally, I am fond of carbon steel, even though it requires more care, and that knife of yours has a great patina which reflects its age.

[Frodo]

list of gun shows in your area   the pitting shown is easily sanded off,  

 if you want to use that knife for years and years, have the pits knocked off and the edged trued by a pro. 

 

• JUNE 5-6, 2021 – PA, GETTYSBURG | Gettysburg Gun Show. ...
• JUNE 11-12-13, 2021 – PA, OAKS | Oaks 3-Day Gun Show !!! ...
• JUNE 12-13, 2021 – PA, LEESPORT | Leesport Gun Show. ...
• JUNE 26-27, 2021 – PA, YORK | York Gun Show.

[chrisash]

There is so much talk about poor blade quality and the need to keep polishing the blade, I do wonder what difference it makes to the average (if there is such a thing) leather worker who cuts out one item maybe a day rather than the professionals who may spend all day cutting out, after all, many but not all would probably just cut out one Wallet, or Bag, maybe a couple of belts in one go so how blunt would a knife get in that process

[chuck123wapati]

6 hours ago, dikman said:

For only $26 I think it's worth persevering with it! I'm sure you will end up with a usable blade. As for your last statement I understand where you're coming from but it's not necessarily the case, it will depend on the manufacturer. The older blades would have been plain carbon steel (hence the rust) but there are many steels available these days that are better, with greater edge-holding and toughness. Personally, I am fond of carbon steel, even though it requires more care, and that knife of yours has a great patina which reflects its age.

Ditto what Dikman said also what Frodo says clean it up and have a new edge put on and enjoy it, your way over thinking this whole process. After the new edge is on you can then more easily learn to keep it sharp.

[chuck123wapati]

12 hours ago, AlamoJoe2002 said:

Thanks Bruce. You have got me thinking...may be I need a new specimen to spend my time on. I truly am looking forward to learn how to properly sharpen and use a round knife.

The blade is still in the electrolysis bath. The pitting is still bubbling the rust away. It has been 24 hours and I don't see much of an improvement to the blade material. I will keep up the process and see how long it takes in solution for the reaction to stop.

So in the mean time I am now on the look out for a round knife to clean up, sharpen , and make it mine. Right now I paid $26 US for the knife. I will begin the hunt for a new specimen. I feel honored to have Bruce weigh in on this project. If anyone has a vintage round knife they would like to pass along at a reasonable price please send a PM. I say vintage because the train of thought is the newer manufactured knives on the market are produced with lesser quality steel.

JOE

Joe

Not always lesser quality steel maybe not as good quality control in thier manufacturing processes but the steel is only a fraction of the equation in making a good blade. I choose and buy old blades quite often but buying a used blade that is still good is also a crap shoot, you dont know how well the old steel has been taken care of it could d have for example been ruined by heat already, left rusty for way to long so that you cant get a clean edge or whatever. When choosing or bidding on used blades i always take extra time looking at the pics for any wear or misuse, in the case of knives, such as this one, with no collector value I am even more particular. This is a good first blade to experiment on it certainly has seen some use but should still be servicable.

[AlamoJoe2002]

The blade has been in electrolysis for 40 hours and is still exhibiting reactivity on all the surfaces. I lowered it by mistake which put more of the tang into the solution and the reaction took off. The reaction resembles very little formation of smaller than a needle point to a pin head bubbles and  appears to be an opaque white stream of material floating away from the blade.

Here is the picture of the blade at the 40 hour mark.

 

I will continue the process. Now I'm really interested on what will be left of the knife when I remove all visible rust and rust down in the pitting.

JOE

[YinTx]

Enjoying learning vicariously.  I noted there is some apparent foaming at the tang pin, and if the ferrule is in contact with the solution, then the wood handle is in contact, which I suspect would eventually lead to wood rot?  Then the handle will become loose in the handle.  Might have been more appropriate to have removed the blade from the handle for the process.  Just thinking out loud.  Thanks for posting the process, and looking forward to seeing the rest of it.

YinTx

[AlamoJoe2002]

That is a good observation Vintx. Originally I suspended everything above the blade, including ferrule above the solution. Then I moved the ferrule about  1/4" into the solution to see what the iron electrolysis will do to the copper ferrule. The should have no reaction to the electrical current. We shall see.

Once the blade is removed from the solution I intend to place it in a oven at around 150 degrees F to dry out the handle slowly. The handle was tight prior to all this soaking. Once dry, hopefully it will return to the steady position it was in before the wood got wet.

I never took apart a knife before...well once or twice with a large hammer...I thought I'd go with a little bit less effort on this handle.

JOE

[chuck123wapati]

13 hours ago, AlamoJoe2002 said:

That is a good observation Vintx. Originally I suspended everything above the blade, including ferrule above the solution. Then I moved the ferrule about  1/4" into the solution to see what the iron electrolysis will do to the copper ferrule. The should have no reaction to the electrical current. We shall see.

Once the blade is removed from the solution I intend to place it in a oven at around 150 degrees F to dry out the handle slowly. The handle was tight prior to all this soaking. Once dry, hopefully it will return to the steady position it was in before the wood got wet.

I never took apart a knife before...well once or twice with a large hammer...I thought I'd go with a little bit less effort on this handle.

JOE

if you dry the handle it may become loose! if you do dry it then you will have to add oils back in to again swell the grain and tighten the handle back up. I have tried the electrolysis method also, went back to vinegar and a wire brush, easier cheaper and faster imo for rust removal now for etching that's a whole other kettle of fun lol.

[dikman]

A couple more thoughts. The handle is held on with a pin, probably brass, I would carefully knock out that pin and remove the handle. There will probably be a bit of rust on the tang too. The handle can be re-fitted later with a bit of epoxy. Once you've got most of the rust removed coat it with a rust converter (phosphoric acid), this should neutralize the small amounts of rust left in the pits and seal it. Grind back the broken corner to give you a point, then sand/polish the blade to the finish you want (a scotchbrite pad might even be enough), refit the handle and sharpen it.

Done. Enjoy the blade. Don't overthink this.

[AlamoJoe2002]

Thanks for all the great feedback. I saw a video on rust converter (phosphoric acid). I will hunt this down. I used this in the past as part of the process of recoating petroleum storage tanks that were rusting to prep for epoxy painting. Great stuff...I bought the coating from a local paint supplier (Sher-Erwin Whatever).

After 48 hours I notices a very small on going reaction. I changed the solution, scrubbed the rebar with a wire brush to expose good steel, scrubbed the knife with a brass brush to clean off the black coating from the electrolysis. Below is the dirty solution.

Here are pics of both sides of the round knife. My focal point is looking for the star under the Osborne Makers Mark. It is there and faint.

 

I reloaded using distilled water from the dehumidifier and less quantity of washing soda. 

I restarted the reaction and it was 20 times more reactive than the 1st attempt. Very aggressive reaction. Below you can see the suspended knife and the reaction of the closest rebar to the knife.

 

I went an checked the reaction and it was very aggressive. The solution had warmed...the 1st attempt never generated any reactive heat.

I must have better connective areas of the blade and rebar (cathode and anode) since I scrubbed them.

I attempted to load a 21 second video. I'm using a chromebook and can't find an good easy extension or app that will quickly resize the video to insert. Ideas on video software requested. I want to show this almost violent reaction that is ongoing and heating the solution. It's warm and bubbling. Enjoy.

Joe

 

[AlamoJoe2002]

Here are pictures of the Osborne Blade after I scrubbed the black iron oxide in water, rubbed down with acetone to prevent flash rusting, then rubbed the blade with WD40. The WD40 seemed to hydrate the wooden handle. I just let this air dry after pulling it and treating it to prevent flash rusting.

I saw a round blade kit that had a few magnets glued flush in wood on youtuber where an individual was developing a sharpening system for round knives. I did something similar but used a piece of granit counter top trash picked on the side of the road. I might not be making any leather goods but I am sure enjoying making a few things and keeping my mind and hands busy. I started at 40 grit sand paper with a block of wood by hand. I have since moved to 60 grit. I think I will experiment with an orbital sander next.

The blade does have character and will remain that way. I received a quick reply from B about their product. Here is a cut and paste from the email. I will say the company is customer service driven. "Please see attached product flyer for Belzona 1111.  This would be your best bet from a Belzona perspective.  1kg unit is $281."  

No epoxy for this renovation! And...I don't see any benifit of filling in the pitting and eliminating the "character" of the blade.

The next update will be when I get time to sharpen and polish the blade.

Joe

 

[MikeRock]

An orbital sander has a rubber pad that will not flatten the steel very well.  Wet-or-Dry paper, backed with a chunk of wood will work faster and flatten what you have.  120 to 600 grit should be all you need.

 

[AlamoJoe2002]

How about I configure and mount a ceramic tile onto the orbital rubber pad and eliminate the soft moving vibrations? Will a hard baked sandpaper  do a nice job? I have an idea where I will use spray adhesive to mount the sandpaper on a granit or marble floor tile. Then make a linkage-dinky-mount on to the orbital sanpaper machine...

Or take all the rubber off the sander and replace it with solid metal or ceramic to attach the sandpaper to the sander....

My friend always is telling me I am over-thinking and incorporating unnecessary steps in a process to achieve results desired....

Make me go Hummm...and my wife kicked me out of my own shop a few hours ago. Looks like tomorrow night is a date night. 

JOE

[dikman]

You're definitely overthinking this! I agree with MikeRock, it should be more than adequate to clean up the blade.

[MikeRock]

Dikman, Thank you.  I have been making metal chips for nearly sixty years and have surfaced and polished up a bunch of round/head knives. 

Hard backed, hand sanding is THE way to go on this gently curving surface, as well as the flat.

God bless

[chuck123wapati]

18 hours ago, AlamoJoe2002 said:

How about I configure and mount a ceramic tile onto the orbital rubber pad and eliminate the soft moving vibrations? Will a hard baked sandpaper  do a nice job? I have an idea where I will use spray adhesive to mount the sandpaper on a granit or marble floor tile. Then make a linkage-dinky-mount on to the orbital sanpaper machine...

Or take all the rubber off the sander and replace it with solid metal or ceramic to attach the sandpaper to the sander....

My friend always is telling me I am over-thinking and incorporating unnecessary steps in a process to achieve results desired....

Make me go Hummm...and my wife kicked me out of my own shop a few hours ago. Looks like tomorrow night is a date night. 

JOE

your friend is right. You could have been done days ago. But thats how we learn i've done the same.

16 hours ago, MikeRock said:

Dikman, Thank you.  I have been making metal chips for nearly sixty years and have surfaced and polished up a bunch of round/head knives. 

Hard backed, hand sanding is THE way to go on this gently curving surface, as well as the flat.

God bless

I agree too.