Pinwheel drum of a Marchant Pony B - cleaning and its manufacturing

The pinwheel drum of the donor-machine was blocked - that is, no column would operate all pin-positions, pins were rusted solid in retracted position. Part as a rehearsal for overhauling the drum of the target-machine, partially to see if this drum could be better and partially just out of curiosity; taken apart for a cleaning and overhaul.

To take the drum out of a pinwheel calculator, one of the sidewalls has to be removed (i.e. a 'bracket', in Marchant-parlance). Then the drum itself can be taken out and apart. First step for that is to remove the pinned gear at the counter-side (the left in image below). Second is to remove the holding nut (red arrow).

The biggest challenge in cleaning this drum was the loosening of the holding-nut. This needed heat (soldering iron) and even some carefully-aimed hammerblows to start moving. (Clamp shaft in vise with protection, eg copper, don't apply any force to the disks!) The taper-pin of the counter-gear on the other hand came out easily. With the counter-gear and holding nut removed, all the sections of the drum simply slide off. Then a collection of 9 pinwheel disks, 3 carry-segments, clearing-arm, clreaing-arm-ring, a collar, one holding-nut, counter-gear, locking-comb, comb-pushpin, comb-spring and of course the main shaft:

The pinwheel disks are held together by two screws and a cover-plate. The carry-pins in disks 2 to 9 are peened in-place and cannot be removed. A brass disk, operating-ring, detent_spring, 9 pins, 2 screws and a retaining plate:

All disks (or dials) are different, specific to the angles of the specific dial digit-position. The timing of the pins and especially the tens-carry is staggered over the drum. The dimensions of the parts for every dial are thus different. Angles are given in the setting of the dividing-table of the slot milling machine.

The diameter of the drum is divided in 37 positions. Central 9 positions are needed for the setting pins, slightly staggered from disk-to-disk -to spread the load of turning the numeral wheels over the turn of the crank. Outside of this centre setting-pin 'field', there are the 10-carry pins spiraling out from dial 1. These carry-pins need one position offset from disk-to-disk to allow a wheel to do a full carry before the next engages.

The steel cams that reset the ten-carry levers are most clearly different; shown in this below drawing - these cams are all stamped with their position number.

The position-specific parts of a dial are all marked with their position number (an obvious and very useful thing to have in manufacturing) - below for example dial number 7:

Dial parts were cleaned individually: steelwool to de-rust the plate and metal-polish for the pins and ring. A very small amount of light, clean mineral oil (sewing machine oil) in assembly and some vaseline rubbed on the retaining plate against rust. When put together again, all pins move - although perhaps not quite as smoothly yet as they would have when new. 

Taking apart the drum also revealed markings from the manufacturing process.

The drum of the donor-machine is marked at the outside of dial 1 with a date and initials. This suggests that employee RA assembled this drum on October 15, 1919 (a Wednesday). 

Several -not all- of the pinwheels (or dials) are marked with initials TH scratched on the retaining plate. Individual disks were assembled separately, with employee TH scratching their initials into every disk they made on the obvious surface to do so. 

Dials were first assembled and stacked per dial-number onto a stake on a wooden plate. There are even photographs of this in the Marchant factory around that time. A store of assembled dials in a 'vault' cabinet from a 1918 article and stacks on a workbench in a cropped detail of a 1920 photo captioned "service department" (?):

Another thing found out when comparing the two drums (and trying to exchange) was that the large driving-gear is not in a pre-determined position to the drum. That was surprising. It is a press-fit onto the drum-shaft that has the keyway to orient all the dials and parts. The gear teeth position appears to have been random, but at a first assembly of a machine the crank-handle shaft would be drilled for the handle. Thus the two shafts are matched in the angle of gears, they work on that specific combination. This was concluded from the gears on the drums of the donor and target machine not being at the same tooth-position. 

The small angular-offset if mixing parts between machines is probably not too noticeable for a regular Pony, but for a Special with the check-dials it means that the check-dial gears won't mesh perfectly centred with the gear on ste setting-dials:

Effect of all this is that replacing a crank-shaft may mean also needing to exchange the drum-shaft. They are matched sets.

Anyhow, continuing the drum re-assembly in 2026. All the clean parts laid out and slid onto the shaft:

And put together again.

And then mounted into the target-machine - both drum and crankshaft from the donor-machine.

The target-machine original drum actually worked relatively fine after a little oil and a work-out. This donor-drum may in the end not be kept in the machine, it does however enable using the straight crankshaft. A restoration choice to be made later; straight shaft, but not the original for machine 70049 - an authenticity question...

The set of drum and shaft from 70049 now out of the machine, to get the same deep-cleaning and rebuild - no scratched-in date, but a stamped A-number instead. Maybe there are some hidden markings on the internals yet to be found :)

Carriage rebuilding of Marchant Pony B

The carriage of both Marchant Pony calculators were partially seized - multiple positions completely unmovable. Additionally, the 18th position of the result-register of the restoration-machine was missing (!), and mangled wingnuts.

At some moment in its past, this machine was radically repaired - repaired from a 'catastrophic event', e.g. being dropped, being hammered. That event is probably also when the main crank was bent, levers broken and the 18th a wheel lost (how??). Not just the numeral-wheel, also its ten-carry lever plus gear was taken out. A small piece of brass was soldered in its viewing aperture in the cover. This was then neatly painted black, making it a 17-digit machine. 

As a start, the target-carriage was completely emptied of all parts - the usual stubborn screws and hardened old oil, but also the counter numeral-wheels were jammed solid between the carriage sidewalls. In the end, an empty and clean carriage; a brass casting with a simple steel strip screwed to the bottom as the sliding surface.

No pictures of rebuilding the counter register - this was hard! to do and was assembled and taken apart at least ten times! One surprising feature and difference with the donor-machine were brass plates or shims between all the numeral wheels. 

These very thin brass plates were all somewhat mangled, probably from brute-force clearing attempts or perhaps a botched assembly. When this shim is not aligned with the main rod, the clearing-pins would 'notch' the brass as the rod is pushed in - this makes extra thickness and pressure on the stack - causing it to be blocked. It is doubtful that all positions of the counter would have worked well after the old repair.

These shims also made it impossible to exchange some wheels with the donor. To accomodate for the brass shim, the wheels are about 6.75 mm wide, whereas on the donor all wheels are 7 mm wide. Well, they really are just under 6.985 mm. This is an American machine; the pitch of the columns is not 7 mm as they would be on a Continental machine, but on the drawings is given as 0.275". Inches and fractions...

(The making of many parts of the Marchant Pony are shown with good explanations, drawings and photographs of the actual tooling in a great 1919 book on Punches & Dies. The book also shows several stamped parts for the Noiseless Typewriter and some Smith Premier typewriter parts. The book can be found in full on The Archive.)

From both donor and target machine, a glut of numeral-wheels. A total of 35 specimens in various states of wear - cleaned and to be sorted on quality. 

Again small differences, the target machine wheels are about 24.5 mm diameter, the donor-wheels are 24.0 mm on average. Probably simply batch-to-batch variation.

Many wheels - a 35 digit register; that'd be a 116-bit register - the actual 18-digit Pony B is already not bad as a ~60-bits computing device :-)

Cleaning, fitting and filing of the the tens-carry levers, then on their rod and screwed in-place. The left-most levers have extra prongs to trigger the overflow-bell (carriage here seen from behind).

After these levers are fitted, the springs and tiny plungers have to be cleaned and fitted to every lever as a rod is pushed in from the left to lock things in-place with an intermediate gear next to every lever.

These are the little spring-loaded pins that keep the tens-carry levers in the out- or in-position. The parts of the target machines are not original - these springs are offcuts of a different size, and the plungers are rounded bits of varying length. Good replacement/repair effort, but not original. The circled three are original Marchant pins with a bevel.

As the rod is pushed in one lever at a time, the springs and pins are selected to give an even, reasonable force needed to flip the lever between positions. Some spring shortened, lengths of pin and springs matched. (Below picture is of a test-fitting, gear-wheel for column 17 needs to be added still.)

Also here the 18th wheel was given a test-fitting - to check if there was something wrong in the carriage-frame, causing the 18th position to be removed. No problems, all works fine. Likely that one numeral wheel or other part was broken, then leaving off the 18th position is the way to solve a lack of parts. The repairer decades ago won't have had a donor machine :)

After the gears-rod is fully inserted and all the intermediate-gears plus all carry-levers are in place, the register can be filled. Starting from the right one position at a time.

To test, first placed on the machine with the first two digits only. The holes vsible on the register main-rod shows that several clearing pins are likely replacements, only few original pins remained. So many pins needing replacement does suggest mis-use; excessive force on the clearing wingnut is needed to shear off these pins - or forcing wheels (perhaps breaking a wheel). The scoring of the numeral wheels also hints at brute-force attempts to move blocked numeral-wheels. This machine really needed to be seriously rebuilt!

The springs for the overshoot-prevention rockers need to be placed with care. When simply pressing everything in place, springs don't enter their pocket and will be mangled and the rocker will be very stiff (blocking?). Several springs were indeed mangled - now replaced with good springs from the donor. 

When everything is in place, the front rack-bar can be screwed in-place. The entire carriage is now clean and functional - well, mostly functional. 

The clearing-flange of the counter is mounted upside-down; that vane should be at the bottom. With the new wing-nut and the pins being what they are, I simply cannot find a position where all wheels clear and no wheels are fouling when zero. In comparison, the 18-digit result register was easy to get to work.

The gear surfaces that slide over the detents are still rough (hard to polish); excercising the digits hopefully will make things smoother. For now the result is one basically functional carriage of a Marchant Pony B calculator :-)

Another Pony to attempt repair of the Pony

It was local pick-up, but last year's purchase of a Marchant Pony B Special was a mistake. Had already seen on the listing that the machine was in cosmetic bad shape (fixable), but had not realised quite how many parts were missing. Too many parts to be recoverable, so first put away in a box.

Just recently however, luck would have it that another badly-damaged Pony B appeared for sale online! The bidding interest in this incomplete and blocked machine may have been puzzling, but it looked to contain just the bits needed to attempt a repair of my Pony number 70049, frame nr. A1007. (The actual meaning and reason for these extra numbers is another thing to be explored.)

So now here a team of Ponies:

The target machine (top in photo above) already partially dismantled and both carriage registers taken out. The bottom machine will be the donor - serial number unknown (no back-plate), but frame number 1828. This donor-machine is a regular Pony B; so no input control-registers as with a 'Special'. The frame and housing of both calculators is mostly identical; to convert a regular Pony to a Special would only (?) require adding the control-register sub-frame (mounting holes are present in the base) and changing the left side-frame and top-cover.

Comparing the two, there are several small design changes visible. The (overly-complex) carriage indexing mechanisms are e.g. subtly different between the two and the revolution-counter is different too. Many/most parts should however be identical (fingers crossed).

Surprisingly the carriages are not interchangeable. The carriage base-rail of one machine is about 0.3 mm wider than the other - carriage 1007 will only fit on machine base 1007 and carriage 1828 will only fit on base 1828. That might be from a small change in the design, but may also be simply variations in size of steel-strip used for the carriage-base - or damage sustained over the past century.

Given the overall character of the machine and its Oakland, CA manufacture it is hard to imagine that this would not be a tightly controlled dimension. Interestingly, though probably simply because it's not relevant at the stage drawn, the carriage-width is not a dimension shown in below part-drawing of the baseplate of a Pony A:

Similarly the carriage indexing/holding pawl looks filed-down to fit its specific carriage - and stamped.

So at least the carriage, base-casting and indexing-pawl need to be matched with these assembler numbers, even the right side-wall of the 70049 machine is stamped 1007! 

The machine covers are then all stamped 49 - for machine 70049. 

Oddly, the carriage cover of the donor-machine has 1828 written (pencil?) on the inside - hard to make out, but it's there. That is odd because a snippet of the serial number is expected there.

Both machines show evidence of major, old repairs (and major mistreatment too). The crank-rest of 70049 shows for example an old repair, the casting fixed with brass (brazing?).

This casting had probably been broken by a major impact or fall, as also hinted at by the mangled crank-handle and a slightly bent main crank-shaft. Crank and shaft will be replaced by the straight specimens from the donor machine.

Another hint that this calculator really has seen mis-use; about half of the clearing-pins on the register shafts are 'new', so something caused all these original pins to be broken or needing replacement. Evidence that it was pretty bad is that the whole carriage is actually bent! See the offset against a straight steel ruler:

Now with an extra parts machine, a repair will be attempted of 70049. To start with, a full dis-assembly of the machine and cleaning of all the bits. One sub-assembly at a time, starting with all the carriage bits.

A full rebuild of one (hopefully) working machine from two damaged ones is admittedly a lot of effort for a Marchant Pony B Special. These Marchant Ponies are not that common overhere, but also not so rare that a decent sample couldn't be obtained in time. In this case it is now more about enjoying the puzzle and discovering the mechanism and design choices of Marchant in 1917.

Finding out how the first American manufacturer of Odhner-lineage pinwheel calculators evolved its design :-)

Spotting a Portable being carried

Adding machines or calculators don't show in contemporary imagery all that often. At least, they feature less frequently than typewriters - makes sense as they would only be found in very specific business settings.

Here one instance where a Burrougsh Portable adding machine is visible in a film. Very appropriately, it is being carried. Handled here in the crime (noir) movie "The Undercover Man" of 1949.

When it's been placed on the table, clearly visible as a Burroughs Portable adding machine with the narrow paper-roll platen.

As the company said; easily carried from desk to desk :)

Forto - least known Dutch typewriter factory?

The three "Forto" typewriters that just topped the Typewriterdatabase list of recently edited galleries are marked 'Made in Holland' by 'Forto N.V. Bussum'. The Forto portable machine has been described before and identified as a Consul machine, a typewriter made by (the) Zbrojovka in Brno, Czechoslovakia. The serial numbers suggest that all three Forto specimens were manufactured in 1961; a relatively rare name-variant of the Consul. But - 'Made in Holland' ?

There was quite some post-war typewriter manufacture in The Netherlands. E.g. by Royal (moving into the premises of a defunct cigar-manufacturer in Leiden), Halberg (later bought by Royal), IBM or Remington. However, Forto NV in Bussum is rather more obscure.

Was this even a factory? Or simply a badging dreamed-up by Zeta/Consul to sell into the US? Doing some browsing through some online archives, it seems that Forto actually was a real company producing metal goods.

The company name "Forto" of Bussum turns up first in 1937, when they get type-approval for their Forto-brand bicycle rearlight. The company 'Metaalwarenfabriek "Forto"' in 1939 gets type-approval for a second model of rearlight (with reflector).

The address associated with the company then, Ruthardlaan 2, is a residential address - the office or perhaps residence of the owner/director (or both). Certainly not a factory.

Then in the above 1947 job posting for experienced die and tool makers a more industrial location is given. This 2e Industrieweg 4 location is a relatively small-scale industrial development of 1936, with multiple workshops around a courtyard and the complex itself surrounded by residential streets. Not certain if this was the primary site, or e.g only a toolmaker workshop.

The entrance to the courtyard, image from an article on the site of the Bussum Historical Society.

In the 1950s they occasionally advertise jobs; mostly girls for assembly-work and boys as press or lathe operator.  (Retirees are also invited to apply.) The job postings indicate the company has presses, lathes and does some assembly-work as well. They perhaps have their own tool-making or maintenance. One of the products they manufacture are weighing scales, as indicated by hiring for the 'scales-department'.

In October 1959 they start hiring for the typewriter department (afd. schrijfmachines); openings for an assembly worker, packer and trainees. (Again, also open for pensioners to apply.) This seems consistent with the typewriter manufacture mostly being the assembly of kits from Zeta/Consul.

The address given is again a residential address. Initially only number 17, then 17-19 suggesting they have taken the whole of the semi-detached villa near the railway station of Bussum.

From all this can be concluded that the Forto brand for typewriters was not created by Zeta/Consul, but was already the registered brandname of a Dutch metal goods manufacturer. They had been doing stampings and assembling relatively simple metal products since at least the late 1930s.

From the -admittedly meagre- indications found; in 1959 they were a factory with experience in metal goods production, but so far there is nothing to indicate a capability to manufacture (under license) a product of the complexity and precision needed for a typewriter.

Most likely is that somehow Zeta and Forto found each other to arrange the local Dutch assembly (with perhaps some parts locally manufactured) of 'knock-down kit' typewriters from Czechoslovakia. Likely done for the sole purpose of giving the machines a 'Made in Holland' wrapping for selling into the US.

By the end of the 1960s most companies have left the relatively cramped premises of the 2e Industriestraat courtyard. Also the Forto company moved out (if they ever were there, it may have been a secondary site). Uncertain from when exactly, but in the 1980s they are located at the Energieweg 35 on an industrial estate in nearby Naarden. Job-postings show the company is then still active in metal stamping, bending etc.; i.e. general metal goods and parts manufacture. 

The Forto company is declared bankrupt in 1994 - the sale of assets announcement shown above gives an overview of their machinery. Presses and milling machines as expected for a general metal goods/parts factory. That is probably what Forto was throughout its existence - even though briefly in 1959 - 1961 they were Holland's Finest factory of Precision Engineered typewriters!

Spanners of the ~1916 Meccano pattern (completism)

I am a completist.

About ten years ago, hesitated too long and missed out on a set of Meccano spanners with large Meccano-stamping then available. This large wordmark dates from around 1916 or thereabouts - and these are much less common than the later nickeled spanners. So when recently spotting the chance to get two, even though a bit pricey with shipping and fees added - went ahead and bought two!

So now my assortment of nickel Meccano of the early 1920s has spanners matching the period screwdriver obtained a few years earlier.

Meccano started marking everything with the brand, reportely in response to the long fight with the pretty blatant rip-off American Model Builder from 1913 or so. This makes dating parts easier, from the presence and the evolving style of the lettering. Many parts were also stamped with a patent numbers/dates. Then a "Fabrique en Angleterre" marking was added from 1921, to comply with new French regulation.

Even though a later 1920s nickel spanner would not be too wrong either, these early 20ies black spanners are a better match for the screwdriver - and make the set again a little more complete. For the complete period-experience.

I am a completist :)

The Burroughs Portable adding machine

The Burroughs Portable adding machine - the type was introduced a 100 years ago, my specimen was manufactured 97 years ago. Having now had it standing for several weeks after re-filling the dashpot to check for any signs of leakage (none!), the repairs to this machine have now (probably) been succesful - fixed :)

The direct-subtracting Class 9 was introduced a bit later than the Class 8 adding-only Portable. The range was designed from the start to be modular, enabling many variations in capacity and features. (Similar to how the 1921 Dalton Super Model range was envisioned.) My particular machine is a Portable of Style 90802: 9 for direct-subtraction, 08 for the 8-column capacity and 02 for hand-operated with 12.5" movable wide carriage.

(rechnerlexikon.de)

After 97 years the anti-glare crackle lacquer is worn away in spots, but it definitely is the wide carriage style. It is massive too.

Sometime in the late 1920s the Burroughs company issued a marvellous advertising book to promote the Portable range. Today this publication is scanned and available via the Archive.

The book gives a fascinating insight in the use of the machine and its selling-points. Note that in 1928 a market survey in the USA found that about 15% of sales were repeat purchases - most adding-machine business was to sell a machine to a first-time user automating existing manual work.

The book repeatedly touts the many advantages of this new portable design; it is only slightly larger than a letterhead!

Technically, that is true. Nevertheless, it does have rather more 'presence' on a desk than the letterhead.

The portability is emphasized on several pages; how easy it is to carry from desk to desk, take it on a business trip. The girl is carrying it under her arm with a seeming nonchalance.

At 19 pounds it indeed is portable. Especially when comparing to the Burroughs Class 1 behemoths or even a Class 3 machines. Nevertheless, it is a hefty chunk of metal.

Another way to look at this adding machine, here the Portable placed next to an Underwood 5 standard typewriter.

Looking at the heavy presence of the Burroughs Portable, note that Underwood did not advertise the No. 5 as 'portable' - the Underwood Portables of 1925 were significantly smaller and lighter. Portability definitely had a different meaning for adding machines.

Introduced with a basic price of 100 dollar it was of course an expensive item, but remarkably low-priced for a quality brand adding-listing machine. It effectively forced Dalton to lower their entry price from 125 to 100 dollar in response. (Dalton needing to create the 'Special' monochrome-only machine in a different finish to justify this new price-point.) It also gave Burroughs an answer to the increasing competition from Wales, Barret and others, many marketing their machines explicitly as being portable. 

A Class 8, basic Style 80801 would've been 100 dollar. A Class 9 with wide carriage would have cost significantly more - probably around 170 dollar in 1928.

Whichever variation, all were solidly built - made by Burroughs in Detroit:

And after almost a century, this particular machine again works fine - a quality product!

With movable 12.5" carriage, able to take an A4 sideways. Also with a roll-holder to optionally print on a standard adding-machine paper roll.

With direct-subtraction - figuring out its age.

And in side-profile. For its period it is a clean-looking and modern machine.

The major difference with the competing Dalton machines; it has a full keyboard like all Burroughs machines. Buttons.

Magnificent engineering! - celebrating its 100 year anniversary this year :-)