The Burroughs Portable ribbon spools; the 7/16" keyhole type

The common Burroughs Portable adding listing machine that was introduced in 1925 uses a narrow, 7/16" ribbon. The spools are also narrow, small-diameter and have a Burroughs-specific keyhole driving hole/slot.

This spool was not created for the Portable line, but it was a carry-over from the Class 3 machines. The Burroughs Class 3 machines in turn are originally the Pike adding machines made by the Pike Adding Machine Company of 1904. 

(Above image from Brandon Smith's video on a Class 3 machine.)

The Pike company started around 1904, their machine was perhaps first sold commercially around 1906. These Pike full-keyboard adding-listing machines were probably selling well enough for Burroughs to notice. By 1909 Burroughs had taken control of Pike; in industry press it is reported late 1909 that the sales of the Pike company are now controlled by Burroughs.

In January 1910 a new model, the Pike Visible is announced. The 7/16" ribbon and keyhole spool may have its origins in this ~1909 Visible design-effort, but probably it dates right back to the original Pike design of ~1904.

The Burroughs Pike Visible Model production starts as/when the Pike operation is moved from their orginal Orange, NJ factory to a new-built factory in Detroit. The stated plan at the time is to make 7000 machines a year in the new, expanded facilities. That would account for a quarter of Burroughs output for 1912. By volume, that is - by value it would be a lot less, the Pike was at the lower end of the Burroughs machines price-range.

The Burroughs Visible is included in the company naming system as their Class 3 machine and continues until it is superseded by the more modern and modular design of the Portable (Class 8 and 9 machines). Judging by the number of these 'Pike Visible' machines still turning up today on classifieds and auction sites, it really did sell in large numbers. 

The Portable of 1925 sold in even larger numbers over ~40 years. It kept the Pike's spool and ribbon; keeping the 7/16" ribbon with the keyhole spools in production for more than half a century!

When Burroughs introduces a typewriter for office work in the '30s, they however conform to the 'industry expectations' and use a regular half-inch ribbon. The original Class 1 and 2 machines used a very wide ribbon, so for a time there were (at least) three different sizes of ribbons sold by Burroughs for their machines.

In the 1950s, the Pike spools are used in the Rooy portable typewriter. An astonishingly thin 'ultraportable' typewriter; a design where 1/16th of an inch saving would be relevant. The smaller diameter of the spool would help as well. 

(Above image shows keyhole spool on M. Schrad's Rooy on The Typewriterdatabase.)

Using the Burroughs adding machine ribbon and spool design meant that availability was not an issue; the Burroughs Portable was in production until the 1960s (as P-Series machines) and the enormous installed base of machines meant that replacement spools and ribbons were widely available. Rooy thus could get the benefit of a 'custom' smaller size part without having to support an own proprietary format.

(Above on the site of Ribbons Unlimited)

And even today these keyhole spools with narrow ribbon are still available! Not just the narrow ribbon, but even complete with appropriate spools. Stocks won't last, but there may still be a lot of these floating around. As a business-only item not very visible to the general public, but the keyhole spool will have been fairly common. 

A succesful design, like the Portable itself :)

Marchant Pony transfer levers - adjusting

The Marchant Pony calculator did basically work after re-assembly, but not very well. It was noisy and 'rough' to operate, although it is hard to tell what these machines would've been like when new. Setting numbers was fine, but adding to the result-register required quite some force and especially the carries would sometimes block the machine. I.e. small calculations worked, but anything with several carries or larger numbers blocked - that for sure is not what it would've been when new.

Adjusting the drum position relative to the carriage already helped a lot with the required force - there are no dowel-pins on this machine to lock the side-brackets, so these can be adjusted a mm or so. Distance adjusted to create the smallest pressure-angle of pinwheel to the intermediate gears, whilst still no parts clashing that shouldn't.

The carries were likely blocked by the transfer levers requiring too high a force to push out. Feeling by hand, some were very hard to move.

These levers are held with a spring-loaded pin against a rod through their slot, toggled between out- and in-position. An extra tooth on a numeral wheel pushes it out, a cam on the drum pushes it back in. In the transfer-lever's out position, it causes an extra count on the next-up numeral wheel by the drum.

Taking the carriage off the machine, the force needed to push out and back in every transfer lever was measured. This confirmed that these forces were indeed very high and also varied a lot per position!

Pushing over 900 gram-force via that tooth by a single pin of the pinwheel is of itself worrying - risk of damage to that single pin. The variation in forces is likely caused by the springs and pins of a position being too stiff and/or rough.

The hole for the spring-loaded pin is (well..., should be) on the centre-line of the lever and centred in the slot, as per drawing. Differences between in- and out-forces then from an irregularly shaped pin, or maybe small deviations of a part. This calculator had very few of the original pins (or springs) left; most are 'crafted' replacements made when it was completely rebuilt sometime in the past. Whatever the reasons; the forces were too high.

With the force-meter at hand to test a position, all transfer-levers were re-assembled one-by-one. I.e. for every position the spring and also the little beveled pin trimmed to bring the forces somewhere between 200 and 400 gram-force. Lower forces to push out would be even nicer, but it became more difficult to make the levers 'snap' to their end-positions when pushed over the centre of their toggle.

After the re-fixing of the side-walls with improved drum-distance and tuning of the transfer-levers the calculator is noticeably lighter to operate. As bonus it's a bit less noisy too. The machine is now capable of doing zero minus one with a ripple-carry over 13 positions - still a challenge, but it can be done. Carries no longer block the machine! All that having been said; it is not as smooth and light-running as e.g. a 1930s Odhner or Thales. This of course may simply be wear of this particular specimen and not its design.

During some more testing, one position started to fail doing a carry. This was caused by the lever not 'flipping' fully to the out position. By pushing in a rod from the right, some 'minimally invasive surgery' was possible on this single position. The offending lever was rotated off the rod to get at the spring and pin. Then re-assembled with a stronger bevel filed to the pin of position 10 - the bevel helps it 'flip' to the end-positions when toggled.

The Marchant Pony B Special calculator; now with adjusted carriage slightly less noisy and capable of 13 carries in a row :-)

Sighting of an old Adler on a shelf

During a trip last week, did a stop-off at a local thrift shop. On a shelf were a well-used Hermes standard and an old Adler. That Adler was surprising; pre-war machines rarely show up in thrifts stores anymore.

The decal on the cover was in great condition with cover-nuts present as well as original spools.

 

This may actually be a pre-pre-war machine; the serial number was I think 4-digits and that'd make it a pre-1914 specimen. (Serial number 6639 ? -should've taken a better picture.)

The drawband was disconnected (still present) and one keylever had been mistreated (bent?), but overall the machine looked complete and rustfree. The nickel should polish up fine, and the wide ribbon looked usable too.

Overall a decent machine with lots of potential to be a very fine ancient typewriter; at 45 Euro an entirely reasonable asking price too. (Left on their shelf :)