Typospherians-

I am T1peM0nkey, and I'm new here. Now that that is out of the way, down to the business at hand. 

With the help of other typospherians, I am attempting to solve the mystery of the 'SX' prefix on Royal 10 Standard machines. Since I began my list of machines we have figured out a lot, and I would like to thank the Davis brothers, Mr. Burbano, and Mr. Weil for their assistance in this endeavor thus far. 

We now know the following: 

In the late 1920s Royal dropped the '10' decals from their machines and stopped using the designation in their advertising. They were still known as the '10' as an internal designation in Royal. In 1928 at serial number 1,200,000 'SX' appeared but was not stamped on any machines. 'SX', as far as we can tell, designates 'Segment-Shift Ten'. The reason that SX wasn't stamped on machines when the internal designation came about is because the segmented machines were wide-carriages, and those get the platen size in inches as a prefix. The first 10s to be changed to segment shift were the 18-inch and wider carriage machines starting in 1928 at serial number 1,200,00. In late 1929 the 14-inch carriages went segment at 1,330,000 and then the standard-sized carriage (at the time Royal's standard carriage size was 10-inch) machines were converted to segment toward the end of 1931 at 1,470,000. The 10-inch standard machines didn't need a prefix for size and were stamped 'SX'. 

With that sorted out, I am now trying to pin down specific features of these machines to determine commonality and a closer estimate of when Royal 10s were discontinued. I'm interested in decimal tabulators, keyboard layouts, carriage widths, condition, etc. 

1. Is the machine equipped with a decimal tabulator? If it is equipped with one, there would be a row of keys above the keyboard that say from left to right:" .  1  10  100  1000 ". If so, is the print black on a white background or white on a black background? If there are these keys, please note whether the color arrangement matches the keyboard or not. Some are known to differ. There would also be a column on the back of the machine if it is equipped with a decimal tabulator. Are there any decals on this column? There may be a Royal logo and then the manufacturing information decal below it. Some are known not to have these decals.

2. What colors are the keys? Are they white letters on a black background or black letters on a white background? Do the shift keys say 'SHIFT' or 'SHIFT KEY'? Does the tab key say 'TABULATOR', 'TAB' or 'TABULATOR KEY'?  The arrangement of the lower right corner's keys will either be [nm,./] [NM,.?] or [nm,./] [NM?.¾].

3. Is the keyboard arrangement foreign? QWERTZ is German, AZERTY is French. The machine is Canadian if it has the £ symbol on one of the keys.

4. Please note whether or not there is a 'Royal' decal on the curved faceplate over the keyboard.

5. There may be remnants of red detailing paint inside the numbers on the paper bail and on the tabulator bar on the farthest back part of the carriage.

6. Is there a plate enclosing the bottom of the machine?

7. Is the text on the margin release curved around the keytop or straight across?

If your machine is a wide-carriage Royal 10 from 1927 forward, I would also appreciate the details on those as well.

Here is an example machine record that is created with that information:

SX-1569247: Ian Brumfield. 1933. Condition: Under restoration. Accounting: No. Black on white keys. Bottom right corner keyboard: [nm,./] [NM,.?] Other keys written as: SHIFT, TABULAR. Margin release: Curved. Location: The Brumfield & Sons Typewriter Co. Collection.