Sunday, March 17, 2024

Awkward adding machine repairs, a Dalton that's not a Dalton

As an entertaining puzzle. Originally this blocked-wreck was bought to be a source of American-size screws and some spare parts, but was also tempting to see what can be learned from it and what could perhaps be fixable.

This is a Dalton, but it is also not a Dalton adding machine. It was indeed manufactured in the old Dalton factory in Norwood, but this is not a Dalton design. This really is a Remington-Rand 'Portable' adding-listing machine. The Remington adding machine is actually the Brennan adding machine. This company had a brilliant, compact design by Thomas Mehan, but had the misfortune to launch new (expensive) business machine in 1929 just before the crash. When the Brennan company went under in the early 30-ies, it was bought by Remington-Rand. 

Remington-Rand had itself been formed a few years earlier in '27 from the merger of Remington, Rand-Kardex, Dalton and Baker-Vawter Ledger. The newly acquired Brennan design was superior to the by-then aged original Dalton design and from '33 the Brennan-design was basis for the new Remington-Rand  'Portable' adding-listing machine.

Most of these new 'Portable' adding-listing machines were sold as Monarch, many as Remington and some as Torpedo (Germany) or Dalton. It seems the Dalton brand was used mostly in export machines, e.g. in regions where the Dalton name was still valuable. This particular 9-column specimen with display, serial number M 150,893 is from 1937. Like many late 30ies Dalton's, this one was also originally sold in Belgium.

A lot of tweaking and oil on several cams un-blocked the main movement. The blocking was caused by hardened old oil/grease stopping lever springing back when they were expected to do so. The keyboard was however badly rusted, the key-stems no longer moving freely in the slots in the equally rusty key-plate. This specimen being a wreck anyways, the keyboard was taken off and taken apart.


These 'Portable' machines are not easy to work on, the keyboard-assembly is really hard to get out (as commented on by bss1250 in his video on a Monarch). Some bending of the outer side-frames is needed to get it out. The bottom-plate can be screwed off and then the routing of the keys to the number-positions is visible - the row of 'prods' that enter a number into memory are at arrow A. The protrusions on the line B are what trips the universal bar (itself in top-right of picture). All the stems C have a delicate spring on it that pushes the key back up.


When the keyboard is removed, the 9-column register can be seen on the machine, slidable on its rails. The teethed/castellated rack in the front of the memory-bank (pin-bed) engages with the escapement, to index it one position on every digit entered. The pin that's pushed down in a column enters a number, just like the original Dalton. (That lever in front was a bit worrying, that fell out when holding it upside down! Took a bit of puzzling to find where it should go - it's the lever that prevents keyboard-clearing when the repeat-button is pressed down.)


All the key-stems are uniquely shaped, they were all cleaned with steel-wool. Having gone this far, the key-plate was stripped and re-finished with dark green paint.

Re-assembly of the keyboard-assembly is 'hard'. The 13 delicate springs need to be held in place on 13 keylevers that themselves need three tabs to be in slots of both top and bottom plates. The hole in the 'prod' of the key-levers now makes sense - this allows a wire to be fed through to keep them in-place during the assembly. Only after several attempts and extra spring-clips to hold things together, was the keyboard put together again - this is not meant for maintenance!


Again bending the side-frame and a lot of puzzling on how the various levers have to be positioned, the keyboard could be screwed back onto the machine. Now with clean key-stems that spring-back easily.

Numbers could then be entered into the machine, the adding mechanism however still made mistakes. When adding 15 to 15, the result was 20 - none of the ten-carry's worked. Adding 3 to 7 made zero.

How or where the mechanism does (or ought to do) the tens carry was not obvious from peering at the mechanism. Reading Mehan's original patent for the mechanism and looking at the drawings gave however a great explanation on how the carry's are supposed to work. (This by the way also made understandable why an 'empty-stroke' is always needed before the total can be printed.)

When a number-wheel (71) passes from 9 to zero, a notch on this wheel (103, marked green) pushes the lever 104 down, allowing the pin 56a on the rack to enter the slot in lever 104 (circled red). The lever 105 on axle 108 (marked red) needs to spring forward to hold 105 down for the carry to happen cleanly.

On this machine, all levers 105 were glued solid on their axle 108 (red arrow, below). This prevented any carry from happening.

With fresh oil and by forcing the levers to move to break the hardened grease, the levers 105 again moved freely. This actually fixed the carry's!; adding 15 to 15 again gives 30.

With the keys also cleaned (they were grimy-black all-over), the whole machine might actually be fixable.

Viewing from the front, the indexing mechanism is blocking the view to the pin-bed memory behind it. The universal bar (white arrow) is what trips the escapement, the long horizontal spring at the bottom pulls the 'carriage' of pin-bed memory to the left. One position at every digit entered.

These Remington small adding machines are not rare and not valuable today, so a good candidate for the occasional puzzling to fix all the other things that still don't work (e.g. the printing mechanism insists everything is a sub-total). And in case of failure and breaking it, not a big issue either.

A 3D crossword-puzzle, as it were ;-)

Sunday, March 10, 2024

First words from the Standard Folding Typewriter

 After probably at least half a century, the little Standard Folding Typewriter typed!

Well, sort of; it still needs adjusting and it will not be a truly daily-usable typewriter ever again. But it's complete and basically functional.

To get there, a new ribbon was wound on the tiny spools. Both spools are identical, the left and right wound the same direction. (The machine is capable of bi-chrome 'black-red' typing, but black is fine and makes adjusting the ribbon vibrator much less critical.)


The machine only had one spool left, so first a new spool was manufactured. Taking measurements of the remaining original, a reproduction was made in brass. In the image above, original is on the left and reproduction on the right. (Reproduction was made with metric materials - the tube originally probably would've been 1/4" with 3/16" and a bit internal diameter. The flange is closer to 0.7 mm on the original. But that's all details that won't be noticeable :-)


The machine also had only one spool-nut remaining, so one replacement spool-nut was taken from a wrecked Corona 3. The design of spool-nut and capstan was changed from Standard to the 3 - the spring-force to retain the 'loose' nut was moved from a split capstan-tube to a deliberate steel spring in the nut. Definitely an improvement, as the split capstan-tube is liable to yield and lose its 'spring'. (And will then lose its nut. And lose its spool.) A Corona 3 spool-nut fits fine on a Standard Folding and actually is a great replacement, as it will hold even when the capstan-tube has lost its 'spring'.

Both the original and the salvaged spool-nut were heavily corroded. The tops were sanded-down to smooth metal and then re-nickeled. Some light surface-pitting is still visible, but the overall appearance is again clean and shiny.

Oddly, this typewriter was also missing its entire linefeed lever mechanism. This must have been a deliberate removing - you need to take out the platen-rod to be able to take this off. Weird.

With today's online resources it is possible to get a very good impression of what the missing parts looked like. Especially some entries on The Typewriter Database with many detailed pictures were useful - also the images on the Words Are Winged blog were again helpful. Counting pixels in pictures and combining this with measurements on the machine and of the Corona 3 equivalent part, reproductions were made in brass.

After nickel-plating and adding the little wire-spring to push the ratchet-pawl to the ratchet-wheel, the linefeed again works and also looks credible. A functional reproduction that is in-style with the original machine.


This derelict-as-was Standard Folding Typewriter now has all missing parts replaced. It still needs a lot of adjusting, but already a vast improvement over its previous condition :)

Friday, February 23, 2024

Blowing out dust - period style

Over decades of neglect, an old typewriter or calculator will collect a lot of dust. Even inside a machine's housing, there often is a surprising amount of dust and debris in the mechanism. 


To clean this out, a soft brush is of course useful - taking care to e.g. not disturb any small springs. Another way is to blow out the mechanism with air.


For a smaller repair-workshop and prior to aerosol cans, there could be used a dust-blower. A wooden cylinder, in this case the 'universal dustcleaner':


These are still fairly common, especially this brand of dust-blower with the flowery label. It is a wooden, rolled tube (veneer) lined with cloth and has a wooden plunger with a leather seal.


The leather-seal on this specimen had been folded back, over the wooden plug. Originally it probably would have been folded forward into the tube, thus sealing against the sides with the air-pressure. Some time in the past this dust-blower was opened and the plunger inserted with the leather wrapped over the plug. To be fair, it's quite difficult to insert it correctly from the back, originally it likely would have been pulled in from the front before gluing on the spout.

The leather had hardened completely, making it difficult to shape it back. A lot of leather-wax was added, to hopefully make it a little pliable again. The seal could be replaced with new chamois, but as it's mainly a historical artefact may just be left as-is. Some extra felt rings were added underneath the leather 'dampeners' on the shaft that also had gone hard - to dampen the plunger 'hitting the buffers'.

From appearance, it could date from anywhere between 1880 and 1920. In fact, most of these are much more recent. The actual manufacturing date is stamped on the plunger; this specimen was made March 17, 1938. (The white dust in the image below is talcum powder, added to make it go smoother.)


It does work - not quite as effective as a pressurised-air can for sure, but durable and very sustainable :)

Friday, February 16, 2024

Carriage on the Standard Folding typewriter

Moving on to the carriage, the front support studs first needed aligning. These three studs are set-screws that were adjusted in the factory and then fixed in their correct position by 'pinning' then from the front. (That is the cause of the small holes in the front-edge of the base, and why there is a central cut-out in the front carriage-clamp.)

The centre stud had become loose and lost its position, luckly it had not yet worked itself completely free. Against a ruler and using the wear as an additional guide, it was re-fixed at (probably) the right height.

With the same method as before, all parts and screws of the carriage were cleaned and bagged ready for re-assembly. 


The feed roller was left in place (could not work out how that would have to be removed). The combination margin-stops / paper-bails are ingenious. The paper-bail finger is always at the edge of the paper, just out of reach of the typing :)

The carriage slides on the machine-base on the two steel bars or strips at its edges. It is simply metal-on-metal sliding, no rollers of any kind. The rear strip rides in a slot in a profile on the base. The front trip rides on the tops of the three studs.

The carriage is then held in place by clamps at the front and back. The front clamp was missing on this machine - using the useful images of Standard Folding 2's on The Typewriterdatabase and especially the clear photos at Words Are Winged, a functional replacement was crafted from 1 mm aluminum sheet. This is not a strong as the steel original, but should hold the carriage on well enough - this typewriter is unlikely to ever again be used heavily.

Painted satin-black, it works to hold the carriage on its rails. It is now again safe to fold the Standard Folding typewriter!

A length of waxed hemp as draw-string and the escapement works! The spring somehow slips its anchor and won't keep the full pressure needed for the entire travel. Maybe this will be looked at, but maybe not - this typewriter will not be used heavily. Rather, the goal of this restoration is for the machine to be preserved. Ideally it should become functional again, but not to the level of it being a practical typer

Now complete with carriage and platen, the little typewriter is starting to take shape - progress :)

Friday, February 9, 2024

Starting on the top-assemby and broken worm of the Standard Folding typewriter

Continuing with the top assembly of the Standard Folding typewriter; the carriage was taken off (is was barely hanging on anyways, with only one bracket left). Then first the carriage base-assembly with the folding-arms was taken apart. End result is a pretty bare baseplate and lots of grimy bits grouped in bags. Only the escapement rack and the rear guide-rail were left in-place.

The baseplate is a fairly basic 'slab' of aluminum, also with the dull, passivated finish. The normal cleaning with soapy-water and vigorous scrubbing would have damaged this finish. As an alternative, the part was washed in acetone, 'scrubbing' gently with a soft toothbrush. (Outside/well ventilated and gloves.)

Bag-by-bag all the groups of parts were cleaned with the usual techniques. The spool-bases had originally been blackened and by now become rusty. These were sanded smooth to the bare metal and painted with a satin-black finish.

Result then; a nicely clean baseplate and a collection of clean sub-assemblies. As stated in service-manuals of the time, assembly is the reverse of disassembly.


So it is.

One unexpected complication was the worm of the right ribbon-feed. This was broken! Somehow it got a knock that spread the worm-thread wider in one spot. This made it jam on the sprocket of the spool capstan; it cannot have worked after that damage. Weird that it even broke the worm where it is fixed with a pin to its axle, but did not destroy the flimsy spool-base. Must have been a very targeted knock.

Fortunately it could be tweaked back into functional shape - well, bent-with-brute-force really and some filing too. The broken and bent-back two parts of the worm were locked on the axle with cyanoacrylate. (In case the worm would've completely disintegrated,  a new worm would have had to be made - could probably have been done; tin-plated copper fuse-wire is soft and available in suitable gauge.)


Mounting the rest of the parts on the baseplate is fairly straightforward. Some bending needed for the escapement plate to straighten it, was bent and would jam in its guide. Probably another damage that happened to the machine after it was last used. Fitted back onto the typewriter base, the little Standard Folding typewriter is taking shape - next the carriage (and several missing parts).

Friday, February 2, 2024

Mounting keyboard and typebars and dulling aluminum for the Standard Folding Typewriter

In preparation for mounting the keyboard 'tapestry' back into the frame, the linkages were sorted on length. They are not numbered, so were kept in sets of 14 for left and right sides of the machine to allow every linkage to be placed back in its original spot. (And of course all were cleaned and rubbed with a bit of vaseline.)

There may be a way, but it didn't seem possible to attach the outer linkages to the key-lever when inside the frame. To avoid that puzzle, deviated from the procedure shown at Words Are Winged and already attached the outermost 4 linkages for both left and right. Also the distance-bushes were added, of course.


This whole assembly was then wiggled back into the machine from the front. The three rods fixed with the screws through the frame-sides. Some painters masking-tape on the front bar to prevent scratching of the paint during the process.

The next step was mount the typebars - these were also laid out in the correct order just like the linkages. A little cloth with oil to give every screw a little dab and tweezers to manoeuvre the linkages back into place.

The typebar-rest on the Standard Folding is mounted onto the front-panel and is what determines the height of all the keys. This front panel unfortunately lost its original dull, passivated finish during the paint-stripping. To get rid of the shiny aluminum and make it suitably 'dull', the panel was glass-bead-blasted -very carefully.

The above image shows the left-half already blasted, the right-end still shiny. The blasting was done carefully; only very low air-pressure and especially a very constrained supply of blasting-material. With aluminum there is a very real risk of creating such surface-stress that the part will warp and deform. First practiced on a scrap test-piece. Fortunately, the panel survived unscathed and is now nicely even and dull/matte.

The rod for the springs was bent ever so slightly - either from a 'bang' or from a century's worth of the springs pulling it (although metal should not relax that way). The rod could be rotated a bit to now be pulled straight - all the springs will stop it from turning, so no need to 'fasten it tight' with the screw-thread.

The original typebar-rest felt was kept, merely given a gentle lukewarm wool-wash and turned over. It is clamped between panel and its support bracket at both ends (and some glue-stick glue on the bracket).

The base of the Standard Folding typewriter is now mostly complete; of course all adjustments remain to be done after the whole machine is fully assembled. (A bit daunting; the segment of a Corona 3 is already a bit tricky; this is 28 separate segments to tackle :-)

Sunday, January 28, 2024

Keyboard repair (and new labels) for the Standard Folding typewriter

After almost 115 years, the keyboard of this little Standard Folding was in a bad state. Most keys had their label and keyring replaced, probably some time in the 1930s or 40s. The replacement rings are a wrong 'flat' pattern and the labels look similar to those used for the later Corona Special machines. To add to this, the 'U' key-lever had lost its key entirely.

Before untangling the 'tapestry' that is a folding keyboard, a picture to note also the position of the spacers at the rod-ends. Some of the key-levers had rusted onto their rod - or rather the rod rusted firmly into the key-lever aluminum bush. These needed several days of oil and gentle tweaking (aluminum is soft!) to loosen them - giving it more time usually helps :)

All key-levers were cleaned with soapy water. Actually, most still needed a scrub with very fine steelwool to make them presentable. Another rinse after the scrubbing to make sure no steelwool debris remains on the parts.

As the key-labels were going to be replaced anyways, the old replacement-rings were removed. The keys are aluminum disks of ~13.8 mm diameter and 2.5 mm thickness (1/10 inch I guess). In the centre a 2.5 mm square hole. Aluminum is an easy material to work with by hand, it's soft and filed easily - nevertheless a 2.5 mm square hole in a 2.5 mm plate is tricky :-)

Keeping a new keyring handy for checking the fit/diameter, the 'U' was given a new key - the lower key-lever in the image above has the new 'U', an original for reference at the top. Looked credible enough.

Using the many useful images of Standard Folding keyboards online and exploring ~1903 typefaces, new key-labels were drawn in Inkscape. The curvy, 'art nouveau-ish' typeface can also be seen on the patent-prototype from 1903, and was kept for nearly all Standard Foldings. Very period in styling. (See patent-model picture on page 200 of the book "Typewriter - a Celebration of the Ultimate Writing Machine" by paul Robert and Peter Weil.)

Couldn't resist and made it a proper keycard. Here below in fairly high-resolution, in case anyone has a Standard Folding in need of new key-labels. (Many of these machines have damaged key-tops - the originals are made from card with a thin celluloid top-coating. This top-layer wears through over time - perhaps from typing with fingernails touching the keys.)

The labels were made with same method used before on the Erika. The keycard was laser-printed on ivory paper, then sealed with artists-varnish and given grey paint on the back to seal/make opaque. This should make the labels last, makes them resistant to wear and to moisture. 

Experimented a bit, and settled on using a 13 mm hole-punch to cut out all the new labels. The same way a set of thin plastic-sheet covers were stamped out. With a set of newly polished key-rings, all parts in place to re-label all the key-levers.

The key-rings were taken from a wrecked 1917 Corona 3. They are not quite the right pattern for a Standard Folding (and not tall enough), but less wrong than the previous and they are from the same company. The rings for the shifting keys are still the 1910 original rings - which is fortunate, because the donor-Corona already had lost a ring and had exactly 28 rings left on it (backspace made 28th).

Some PVA glue was placed on the keys before placing the label to prevent it rotating - and the PVA should not adhere to the aluminum and will make it possible to cleanly undo this restoration later. Firmly pressed down the stack of label and plastic cover with the ring and folded over the tabs with a screwdriver-tip to fix it all in place. Only one tab broke (unfortunately), so a small dab of cyanoacrylate placed there. (Cyanoacrylate is by the way also safe for restoration, it can be cleanly removed by heating it - placed in hot water it will lose all strength and fall apart.)

Then weaving the re-labeled levers and spacebar back onto the three polished rods, the assembly is ready for inserting back into the typewriter. Looking much better (and safe to touch again ;-)