New typeshuttles for the Hammond - How to make

After some experimenting (and many failures), the workflow for creating new Hammond typeshuttles is starting to form. 

A new Hammond typeshuttle is assembled from several parts, just like the original. The individual parts have to be modelled, manufactured, finished and then assembled.

The core of the original shuttles (above) were two nickelsilver strips; one as flange to ride in the slot of the anvil and one curved 'vertical' that was embedded in the vulcanised rubber. The vulcanised rubber is the actual black bit of the shuttle that contains the characters or typeslugs, impressed from the mold. A small metal 'grip' collar was fastened with two rivets to the flange as take-up for the machine's driver-arm. An original Hammond shuttle could thus be seen to be made up of 6 different parts. These parts and materials all have different properties - also needed for their function. 

In re-creating a Hammond-compatible typeshuttle is is also necessary to build it up from different materials, with different properties.

Build-up of new shuttle

The new typeshuttles are built up of the shuttle-strip that contains the characters, a steel flange and a small take-up collar. The 3 parts are glued together, optionally held in a jig for correct shape and alignment.

 

Grip

The small take-up collar or grip is 3D-printed in PLA material on an FDM printer. Using a 0.2 mm nozzle, a precise and fine part is printed, with PLA being very strong at room-temperature and highly impact-resistant. The part is small, so even with a 0.2mm nozzle the printing is fairly fast. Optimal results from printing by-object, no finishing should be needed.

Flange

The steel flange is laser-cut from 0.2 mm stainless steel. These were ordered from a local shop, that does lots of laser-cutting. The parts are perfectly flat and were cut with an industrial-quality machine under protective gas so no cleaning or finishing is needed. Ordering a batch of these can make it quite reasonable and relatively affordable. (I.e. in the context of a Hammond typewriter :-)

Assembly jig

The assembly jig is optional; the grip, flange and strip have alignment features that enable correct assembly. For especially the resin-printed strips however, it may be essential to re-shape these with the jig. Resin-prints have residual tension and the curvature of the part as it emerges from the printer after cleaning off any supports is not reliably correct! The jig is not too critical and can be simply printed with a 0.4 nozzle on any FDM printer.

The model-files for these parts can be downloaded here.

Shuttle strip

The shuttle strips with characters are generated using a scripted 3D modeller. There are several of these programs, in this case OpenSCAD was used. The script was created for the current 'stable' release and everything was kept in one file without external dependancies (except of course the font-file). This should make it reasonably robust and easy to get working anywhere to generate a printable model. (Development-builds have some new features that could really help in creating better, nicely aligned, monospaced type.)

The script contains already a couple of layouts, selectable by uncommenting a single line further down. This selection-line also includes several extra parameters, optimized for that specific layout (the obvious one being number of rows). Some of the available layouts illustrated in 'preview', i.e. not yet with the type mirrored:

The script also contains lines for selecting a typeface, a font file that has to be present on the computer and available to OpenSCAD. This can be 'tricky' and may require tweaking to properly fit all the characters on the shuttle. Not every font contains all characters (glyphs) that are needed for a layout. Fontfiles also contain errors; the character may display fine on screen, but a small error can prevent the character from being able to be generated as a 3D typeslug.

Generating the actual, correct 3D model from the script is a computationally intensive task. Even on a fairly fast computer it will take several minutes, up to half an hour - depending on the complexity of the typeface. Every character is generated from the glyph in the fontfile with a tapered base. This taper is done for strength, naturally, and also to enable the 3D printing process to generate the shapes (limit overhang-angles).

There is the option in the script to generate a file for resin-printing - permitting fine detail - or for FDM printing with additional bed-adhesion features. The model generated for FDM also contains modifications to the 3D model geometry to compensate for limitations of the FDM process itself.

The shuttle strips will need some finishing after they've been printed; supports and adhesion-feet will need to be removed. Any remaining marks should be sanded smooth. Especially the inner curved surface must be made very smooth and clean; this has to slide over the anvil. FDM-printed strips in PLA are generally pretty good on dimensions and have the correct curvature, but resin-printed strips will need some time in the assembly jig to be 'bent' back into shape - the material does relax and settle in the correct shape after an hour or so.

The STL 3D-model file for an English Universal shuttle strip with a regular Roman typeface can be downloaded here for resin-printing and the file for FDM printing with a fine, 0.2 mm nozzle can be downloaded here.

The OpenSCAD script file has embedded comments that should help understanding what everything does, and what parameters to change when creating new shuttle models. It also should make is fairly easy to expand and adapt for new layouts or otherwise improve upon. The version of the shuttle strip script used to generate the above models can be downloaded here. (Whilst it is commented, the code itself is not very good. There is sloppy parameter-passing, many variables are global and used throughout. The code could do with re-factoring and probably be optimised for speed. I.e. options aplenty to tinker and improve - but it works. My Mignon type-cylinder code is much cleaner, having learned :-)

Assembly of the typeshuttle

Having a properly smoothened strip, a flange and a grip, these can be placed in the jig.

To fix the parts, a drop or two of cyanoacrylate glue are applied with a toothpick to where the flange sits in the strip's groove. 

Capillary action and some help from a scrap bit of card will spread the glue over the entire length of the shuttle. (Picture below was taken when the ends still needed a proper push into the groove.)  Despite its reputation as fast-setting, allow several minutes (hours!) for the cyanoacrylate to properly harden out.

If everything went fine, then the newly assembled typeshuttle should fit on the anvil on a Hammond typewriter. It should slide around freely without any binding. If there is binding, the shuttle strip may be a bit deformed and need further sanding - this is actually fairly likely with resin-printed strips, FDM strips usually are fine as are. The grip may also need a bit of smoothing on the side it runs against the inside of the anvil - e.g. run a bit of sandpaper (180 grit) through the shuttle against the sides to smoothen all surfaces.

With all this done, the Hammond typewriter has another typeface added to its repertoire ;-)

As warned by the Hammond company; do not use oil on the shuttles - if wanting to lubricate, perhaps apply a little talcum powder. It should run fine without any lubrication though.

In conclusion

With the above workflow, new typeshuttles can be made for the Hammond typewriter. It thus becomes possible to use the antique machine without risk of damaging an old, original typeshuttle. The original shuttle's hard-rubber is relatively brittle and can easily crumble or chip. It's also possible to re-create shuttles with otherwise rare typefaces or layouts - or make shuttles with completely new layouts and typefaces.

Creating these new typeshuttles was only possible by building on top of the awe-inspiring work done in making new Selectrix typeballs; especially the work and example code of Dave Hayden of selectricrescue.org was instrumental in getting things this far. Sharing experiences and discussing designs with Leonard Chao really helped getting it all to work. He's been doing amazing work on 3D printing new Blickensderfer cylinders and Hammond shuttles too!

And of course made possible by open-software design tools OpenSCAD and FreeCAD.

The ability to make new shuttles should enable Hammond typewriters to continue typing far into the 21st century; usable Hammond typewriters! :-)

Dalton Adding Machine serial numbers, estimated agelist

An estimated, approximate agelist for Dalton Adding Machines; serial numbers are start-at for the year.

The ~1927 issue of Business Machines and Equipment Digest contains an estimated serial numbers agelist. This list with details about changes over the years was likely provided by the Dalton company itself. 

Taking this list as a starting point, a full agelist with serial numbers from the start of production in ~1907 to the end around 1933 was estimated.

Added were any hints from period literature (e.g. start of active marketing), advertising and competition. E.g. the introduction of the Special 100-dollar Dalton was very likely the direct consequence of the Burroughs Portable being introduced in 1925 for 100 dollar.

The Dalton machine was probably also expensive to manufacture, relative to the Burroughs Portable. Even after the re-design into the Super Model range; this replaced many castings with stamped parts, but the machine was still very heavy for its capability and remained fairly complex in assembly. The Special being offered for 74 dollar via Sears in late 1929 must have been bad for margins - Dalton was likely losing badly from Burroughs by then and perhaps 'desperate measures'. 

The Brennan, despite its unfortunate launch-timing in 1929 was a 'better' machine than the Dalton. It will have been significantly cheaper to manufacture, was more compact and offered roughly the same functionality. Even though adding machine sales overall probably 'tanked' the years after the Wall Street Crash, the Brennan would have been a competitive 10-key offering versus the by-then aged (old-fashioned?) Dalton. (Notable that Remington-Rand hardly used the Dalton brand for their new Portable adding machine, but instead mostly marketed these from around '32 as Monarch or Remington-Rand.)

The published agelist in the Digest shows an overlap of Old Style and Super Model production - putting this in a graph gives a good impression of average annual volume of Dalton. It also suggests that annual sales of the Dalton company were probably around USD 20M at its peak.

The serial numbers after ~1929 become more uncertain and rough estimates. The company probably struggled as part of Remington-Rand, but would surely have continued to manufacture and sell machines right up to the switch-over to the Brennan-derived machine. Doing a quick inventory of machines that can be 'sighted'; the serial numbers probably did not go much beyond 212,000.

The sightings also give a clue to the different color-schemes of Dalton machines. From the start of production up to around 1926 the machines are lacquered plain black. In 1926, there was a switch to a crackle black and for the Special machines a 'crystalline green' finish. The Specials were finished in green for several years, but not all Specials - there are also crackle black specimens.

Then in 1928 Dalton switched to the brown woodgrain finish - judging from typewriters in woodgrain finish, that was just about then becoming very fashionable (and practical for manufacturing).

With more data and analysis, the agelist and e.g. the chronology of finishes can certainly be corrected and improved upon - this is a quick, first guess/estimate.

Anyways distilling all this; an estimated (!) agelist for Dalton Adding Machines :)

Attempting a repaint of a Dalton Adding Machine

They are not rare and today certainly not desirable or collectable, judging by online offers - the later-models Dalton adding machine are pretty big and 'boring' machines with, well, limited functionality. Nevertheless, got distracted further from ordering new 3D prints and started taking apart the donor-machine to see what could be done to make it look a bit better. On the one hand it's not a machine worth the effort, but on the other hand would be no big loss if it all fails and it's reduced to parts-donor.

The re-designed Dalton 10-key Adding Machine launched in 1921 as the "Super Model". With this re-design the company did away with the original-model's four cast-iron frame-plates inside a single-casting housing, and replaced this with four stamped frame-plates and thin sheet-metal panels on the outer frame-plates. This did make it lighter (a bit), but it certainly made assembly more complex and made the frame part of the exterior. To re-paint, the frames have to be removed!

Removing the outer frame-plates only one at a time, much of the mechanism is held in position - this limits the trouble in getting things back together again. Only a few levers and brackets come off - in this state it is even possible to see the register-wheels, but only just. That the register wheels are so deep inside the machine and obscured, with every mechanism connected to every other mechanism must have made it a nightmare to assemble (costly too).

Despite the sorry-state of the machine on the outside, the mechanism was only dirty and completely rust-free! One other reason to take it apart this far, was to try to fix the oil-damper. That failed - the damper can be taken out fairly easily and be cleaned on the outside. It however could not be opened, it's just been tightened too hard with a copper gasket - and has no filling-plug. Dalton likely did not anticipate this to ever need servicing; to be fair, a reasonable design-decision back then :)

The fancy machine-spotting applied on some of the internal parts also came out very clean again. Still looks great - but normally hidden behind the body-panels.

With the machine broken-down to the core-mechanism, the typeslugs can be accessed for a cleaning. Just as in typewriters, these do catch ink and 'lint' from the ribbon - especially the lower columns digits were clogged.

Now clean.

After debating what colour to paint the machine (crystalline green? ivory? silver?), settled on plain black. The function-keys on a Dalton are color-matched to the body - and these are black on the machine. It'll just be gloss-black however, instead of crackle.

It should come out nice - that is: if it comes together again!

Klein-Adler with an extra trick

This cleaned-up little Klein-Adler has an extra lever compared to most others. The lever at the left is carriage-release, that lever at the right however is less usual. Couldn't find any other Klein-Adler that's pictured online (and many are!) with a lever there.

The lever actuates a prod at both ends of the carriage. The lever and mechanism is screwed into the ends of the paper-tray. This prod seems clearly designed to hold something, e.g. a ribbon-loop of ~8mm high.

Looking at this, the idea was that this could be a bichrome feature for the Adler. 

Adler thrust typewriters are a bit peculiar in that the ribbon and its 'toggle' is fixed to the base of the machine and not moved with the platen. That means that the platen moves up-down in front of the ribbon, ergo a ribbon needs to be the same width as the height of the type-slugs (i.e. very wide on this 3-bank). It also means that two-color ribbons are 'difficult'.

This lever and rods contraption looked like it could be a two-color typing mechanism, similar to how e.g. the Hammond implemented bichrome typing by simply lifting the red in front of the typing-line.

To test the hypothesis, a red imprint-strip was mocked-up with modern crafting "carbon paper". Had considered a length of 8mm ribbon, but that would soil the main ribbon and vice-versa. Carbon-paper actually is designed for exactly this type of 'manifolding' function.

The fitting was actually very tricky. It took a couple of tries to make a strip of the right length. The mechanism also needed some forming to make it clear all other parts and regain its bi-stable spring function. A long rod at the back functions as a holding-spring against the paper-tray ridge. This gives the whole thing stable down and up positions. In the up-position the strip is exactly on the typing-line - also blocking the view of what is typed: blind-typing. In the down-position it is clear and does not interfere with typing.

It still is a bit temperamental, prone to snagging on the type-guide - but as is clearly seen in below side-view the coloured strip moves with the platen and the wide ribbon is fixed to the machine-base.

It actually does work!

When the color-strip is in the up-position, the typing is of course blind. Am curious what type of strip was originally provided with this contraption. Also unsure if this was a factory-fitted feature or an aftermarket device. It matches the overall design and engineering-style of the machine and intricately fits the mechanism. It's also something Adler could/would have felt it needed to compete - by 1925 the Klein-Adler really was a bit outdated and lacking in features versus the competition. No bichrome for example :)

On the other hand, it's a bit fragile and convoluted. A machine on The Database only 10 removed from this one does not have this two-color function. On The Database is machine 315125 and this is 315115. Both machines actually have a Dutch florin symbol, but the '125 is a QWERTZ machine instead of QWERTY as this '115.

If a factory-option, then would've also expected more specimens to be visible online or some documentation. 

Quite possibly more information will turn up about this Adler two-color feature; something will have been written down somewhere sometime. For now, this Klein-Adler just has a neat trick; it can write in red too :-)

Putting the little 3-bank together again (and a nickname)

After cleaning the bits, put together again quickly. The Klein-Adler with lots of sliding parts in the typing-mechanism is vulnerable to dirt - a thorough cleaning and removal of decades of patina (oxidation) should make it work much better. The keys go in fairly easily, slotted into the comb and with a single spring.

The typebars can be slotted in from above - the whole mechanism looks simple and elegant. This was not the first version of this mechanism they made, for sure.

The cleaning did make it better, it now types very well - 'snappy' even. It unfortunately has a rock-hard platen, but with one or two backing-sheets it types great.

This little 3-bank typewriter is the first machine here that got a nickname. The reason for that was - to start with - that it has a wooden leg (one foot had been replaced with a cork, painted black):

And that it has one shiny nickel and one black spool; the machine does look as if it has an eyepatch:

To add to the story; it has a scar on its visage (broken glass of the 'O' key):

And to round it off; silver buttons on its coat:

Of course this Klein-Adler got nicknamed Short John Silver ;-)