Simpson tenon saw 1, the saw plate and spine.

Last time out here at sea, I ended up swaying back and forth between making an infill moulding plane, or a tenon saw. I finally decided that a saw was the way to go, and i started looking into finding some steel for the saw plate.
This time I wanted to make a tenon saw, so I couldn't just buy a plaster scraper as I did last time I made a saw - I needed something bigger.

Luckily I know Pedder from Two Lawyers tools, and I wrote and asked him about his ideas for using steel shims for saw plates.
He looked at the specifications and found that it was rather soft, and immediately offered to make me a saw plate and stamp some teeth in it at the same time.

When the package arrived, there wasn't just the saw plate, but also a very nice old large tenon saw in there as well.

I figured that rehabbing an old saw would be a fine way of getting some experience before making a tenon saw from scratch. So I brought both this tenon saw and the saw plate with me on board.

The first thing I did was to remove the handle. The brass screws and nuts loosened easily, and the handle came off in no time.
Removing the spine was a lot more difficult. It pinched the saw plate pretty hard, and at the same time there was a bit of rust to help bind those two together.

With the steel parts separated, I got a bit of metal brightener from the guys on deck and washed the parts in that. I think it is some sort of phosphoric acid mixed with soap. It seemed to work pretty well.
After the metal brightening, I sprayed the parts with some thin oil and sanded them with emery cloth. I didn't go all wild since there are some pitting that I can't remove. I also don't mind that the saw will still show signs of being old - as long as it will work.

I tried to do a bit of searching about the saw maker, but searching for anything containing the name "Simpson" will generate a bunch of hits with a yellow faced cartoon figure that likes to drink beer. So I gave up on that quest after a few tries.
Mostly I would like to know the approximate age of the saw, and one of the few non cartoon hits I had suggested something like the early 20th century.
If anyone else knows something about the Simpson saw making business, I would be happy if you left a comment.

My plan is to make a new handle for the saw, since the old one has got some worm holes and also some damage to the horns.
I brought some stock with me for that purpose, two pieces of elm and one piece of whitebeam (Sorbus Intermedia). I thik that I'll go for elm as material but in case that doesn't work, I'll still have a possibility of making one out of the whitebeam.
The handle will be a direct copy of the old one.

Handle of old tenon saw. 

Removing saw nuts.

A bit of rust damage, but still usable.

Cleaned and oiled saw plate and spine.

SIMPSON

GERMAN STEEL