Forcing a patina/bluing/etching on knives with fixed scales?

[leozinho]

This might be an easy one for you guys.

I've got a couple of knives ready for heat treat (the refractory cement on my paint can forge is curing as we speak). I haven't gotten to the handle making yet.

I like the look of the dark etched knives done I think with ferric chloride.

I also get a headache trying to figure out the bolted scales (countersink this, counterbore that, everyone is out of the standoffs or the black oxide flat machine screws, etc.) So imagine I want to fix the scales with pins or corby bolts.

What I would imagine I would do is etch my blade (1084 from Aldo), attach the scales with pins or corby bolts, and then grind and sand and polish the scales.

But wouldn't grinding, sanding and polishing also take the etch off the spine at the handle and leave that portion polished? I want the spine to have the same dark color as the blade.

Thanks.

 

[Doug Lester]

Yes, it will take the patina off the spine. Here's how I had to do it when I wanted an acid blued handle on a knife. I permanently attached the guard and pommel to the knife and then fit the scale blanks and pinned them in place with temporary pins. Then I ground everything the way I wanted them. After that I drove the temporary pins out, being careful to mark which end was up and which side the scale came from. I didn't want to acid blue the blade so I had to coat it with a resist (obtainable from an etching supply/art store) and apply the acid to brown the handle then boil it to turn the rust blue (actually, more of a black). The scales were finished off the handle and reattached with permanent pins and epoxy. Stray epoxy can be cleaned off with WD-40 on a cotton applicator if done before it dries. The resist was removed from the blade with mineral spirits. In your case you would just apply the patina to the entire blade and leave it.

If you use something like Corbie bolts you will have to drill and fit them to the scales without grinding them flat. You will have to shape the scales except for the middle around the bolts, disassemble them, apply the patina, reassemble the handle and grind the bolts flat and touch up the finish on the scales. Pins would be simpler.

Doug