Rebluing part of a bayonet?

[IditarodJoe]

I recently purchased a low s/n 1905 bayonet (made in early 1906) that I am going to “restore”. The bayonet underwent the 1907 alterations and is in overall very good condition, except that at some point in its life the blade was shortened by three-quarters of an inch and the entire bayonet was plated (either chrome or nickle - I can’t tell the difference). At this point, it has no collector value, so I figure I can't hurt it too badly.

I have access to an aerospace metal finishing company that says they can remove the plating for me, but I’m not sure where to go from there. According to Brophy, the bayonet was niter blued to about 1/4 inch ahead of the crosspiece and the blade was polished bright metal.

Has anyone here had any experience with having “part of” a bayonet reblued?

Any advice or insight will be appreciated.

[JB White]

British blades were suspended by the blade and lowered into the solution. I would imagine something similar with US bayonets finished in that manner.

[IditarodJoe]

Thank you for that piece of information, JB. I've been looking for a good photo of an original early 1905 to determine how "crisp" or "sharp" the line is between the blued portion and the polished metal of the blade. I would think that simply suspending the bayonet over/in the bluing tank would result in a somewhat hazy boundry. If the originals have a sharp line betweeen the two areas, I would be inclined to think that some sort of masking or pre-coating of the bare metal was involved.

Does anyone have a good photo I could use as a reference?

[Bayonetman]

Here is one:

[Nick Riviezzo]

I really don't know anything about this subject but the logical conclusion,for me, is blue the whole bayo and polish/grind off what doesn't need to be there.That will give you the desired texture on the blade and a straight line of"departure"wouldn't it? Nick

[dave]

Do not take that 1/4" as written in stone. I have seen many that it is allot less. Mine is 1/16" and it is original 1906 RIA.

[IditarodJoe]

That's a great photo, bayonetman! Does that straight edge continue evenly around the upper and lower edges? The crispness of that boundry would seem to me to rule out the suspension approach in the bluing tank, as any motion of the surface of the bluing solution would make a more blurred transition.

I hadn't thought about Nick's suggestion. If my understanding is correct, for a very short time at the beginning of WWI the blades, as issued, were entirely blued. If the blades have previously been entirely blued and then the unwanted blue polished off, the elimination of the polishing step would have been a logical wartime expediant. How difficult would it be to polish off unwanted bluing?

Here's an interesting update. The bayonet is currently at the metal finishers being stripped. When I took it in, they told me that when "decorative chrome" is applied the common procedure is to first nickel plate the piece and then to apply chrome plating over the nickel. According to their expert, this was the case with my bayonet.

I should have the stripped parts back this week and will post "before and after" pictures of the result.

[Bayonetman]

Yes, the line of blue is consistent around the blade.

The width of the line of blue is not totally consistent, but remains very close with Springfield Armory being about 1/4 inch, and Rock Island being somewhat less, in the area of 1/16th to 3/32 inch. However, there are exceptions to both.

There has been a lot of discussion over the years as to how the bluing was done. The idea that they were blued overall and then the unwanted bluing was polished off has been discussed, and may well be correct. However, I have no definite information as to how this was done.

[Nick Riviezzo]

Again, coming up with"brainy ideas" that I know nothing about,would it be feasable to blue the whole thing and remove what and where you want with Naval Jelly?You could maybe mask your line with electrical tape to get a clean line.For sure I know nothing about bayos[except how to use one] but I'm trying to think of a shop[shadetree] procedure that would work for you. Nick

[Johnny P]

There were no blueing tanks when the SA and RIA bayonets were made. The two blueing types available at the time was rust blue (called browning), and niter blue which was a heat blue. The hot tank caustic blue did not come into general use until the 1930's.
The niter blue produces a beautiful blue, with the higher the polish of the metal, the brighter the blue. In the niter blueing the part is repeatedly dipped into a mixture of potassium of nitrate and oxide of manganese heated to 800 degrees F. It would have been easy enough to suspend the bayonet handle down into the mixture, as the process was probably done by hand, and then polish the blue back to a smooth line.
On the bayonet you can see that the polish line was not straight, and is lower on the right than on the left.