Strange black splotches on a Diamond 8000

[Steve56]

1. My personal experience is that you will still have a pitted blade after the best that can be done. You won’t know if it will look better until you try. Not all of it will be deep, but some of it will be deep.

2. If it’s clean it probably is inert. Try a hobbyist fiberglass brush to clean out the pits then put some Renaissance Wax on it. It will likely be inert then.

3. You deal with that by honing - you’ll have to get to sound metal at the cutting edge just like any other rust.

4. If this is your first restore, I’d go the fiberglass brush and Ren Wax route. There have to be many razor/knife ‘mechanics’ in Japan that could refinish it as best it can be done. If you decide to proceed, I’d at least get some advice from a knife/razor finisher.

Good luck!

 

[Sukeroku]

1. My personal experience is that you will still have a pitted blade after the best that can be done. You won’t know if it will look better until you try. Not all of it will be deep, but some of it will be deep.

2. If it’s clean it probably is inert. Try a hobbyist fiberglass brush to clean out the pits then put some Renaissance Wax on it. It will likely be inert then.

3. You deal with that by honing - you’ll have to get to sound metal at the cutting edge just like any other rust.

4. If this is your first restore, I’d go the fiberglass brush and Ren Wax route. There have to be many razor/knife ‘mechanics’ in Japan that could refinish it as best it can be done. If you decide to proceed, I’d at least get some advice from a knife/razor finisher.

Good luck!

Thank you for your detailed response. I usually collect Tanifuji but I could not resist this Diamond Hayashi, even if it is a restoration project. It's all part of the fun!

 

[global_dev]

Does anyone have an idea of what these splotches on the blade are?
The razor is in minty conditions except for the black spotches. Can
they be removed? If so, how? If they cannot be removed do they
damage the structural integrity of the blade or is it merely cosmetic?

View attachment 1243504

For The appropriate price this would be a great pick-up. Not every blade has to be the pageant winner, but if that steel is sweet and the grind good to go, that shave will make you smile

 

[Eastcoast30]

So, do you recommend that I just leave the devil's spit as is? Is the black corrosion inert? I do need to deal with a section near the
cutting edge which, under magnification, has worn through to the other side. The scales, and gold etching on the tang are just perfect. I want to fool with it as little as possible. However, I do not want it to get any worse. My plan now is to hone with the chosera 1k until I get some clean steel and then sharpen it on the Jnats. If you think that I should leave the rest of the corrosion on
the face as is, I won't touch it. What is the best plan of action?

If that portion of the edge has worn through, treat it like a chip and hone it out. From the photo, it appears small. And again, trying tp remove or sand all the pitting will ruin that beautiful finish that the grind makes.

 

[Sukeroku]

If that portion of the edge has worn through, treat it like a chip and hone it out. From the photo, it appears small. And again, trying tp remove or sand all the pitting will ruin that beautiful finish that the grind makes.

I spent some time with a fiberglass brush and was able to get most of the corrosion cleared out without ruining the finish. There are
some particularly deep pits that I may need to work on some more. The only sacrifice was some of the gold paint on the engraving section but I may be able to repaint that. I also got all the rust out of the edge and now it looks like a normal chip. I will try to
work out a new bevel with a 1k chosera. I really want to thank a few members here who have been generous with their time while patiently answering my numerous PM's on this project. I will post pictures when I'm done. Those scales and wonderful tang covers are what keeps me motivated to bring it back to life.

 

[Frank Shaves]

Great to hear! Can you also post a photo of the fiberglass brush? I have never heard of these and would like to know more.

 

[Steve56]

@Frank Shaves

This set is nice because it has multiple brushes. Brass, Steel, nylon, fiberglass. The quality isn’t as good as the German ones but it’s good enough.

Pixiss Scratch Brush Pen Set, Fiberglass, Steel, Brass, Nylon, 5-inches Pen Style Prep Sanding Brush 4-Pack for Removing Corrosion and Rust, Jewelry, Electrical Circuit Boards and Auto Body Work: Amazon.com: Industrial & Scientific

Pixiss Scratch Brush Pen Set, Fiberglass, Steel, Brass, Nylon, 5-inches Pen Style Prep Sanding Brush 4-Pack for Removing Corrosion and Rust, Jewelry, Electrical Circuit Boards and Auto Body Work: Amazon.com: Industrial & Scientific

www.amazon.com

 

[Eastcoast30]

That's the set that I have. But it will not remove the pitting (black oxidation) by itself. Did you use a polish or abrasive with the brush? And again, it was the fiber brush and not the nylon. The nylon is stiffer.

 

[Sukeroku]

This is the one I bought. There were not too options in Japan that did not cost $30+. This one was about $10.

 

[Steve56]

$10 is about right for the good ones, and that one looks like it is a good one.

 

[Eastcoast30]

This is the one I bought. There were not too options in Japan that did not cost $30+. This one was about $10.

View attachment 1253745

Did you use any paste or polish or did you just use the brush?

 

[Sukeroku]

Did you use any paste or polish or did you just use the brush?

Just the brush, a light touch and patience...wear some eye protection and be careful of splinters.

 

[Eastcoast30]

Just the brush, a light touch and patience...wear some eye protection and be careful of splinters.

Thanks!