Sunday, September 28, 2014

Rubber rollers and carriage re-assembly

Having gotten all the rollers off the carriage (amongst several other items...), on to fixing all the rubber.

The rubber on the front-rollers had gone soft and tar-like, so cleaned the front-feed rollers down to the bare brass cores. Seems odd, but Remington must have used different rubber for the front rollers, rear rollers and platen as they all have deteriorated in their own particular way. Perhaps different suppliers.

Anyhow this meant the front feed rollers needed to be re-made. With their small diameter only two layers of small diameter heat-shrink tubing was enough to make decent rollers again. Small sleeves of about the right width were cut off and a hairdryer at the max has just about enough heat to shrink the tubing nicely around the brass cores. (Pliers to hold roller on rod in front of heat.)

The rear-rollers had flat sides, but otherwise still fine. Before cutting it all off and making new from heat-shrink tubing, first wanted to try to make the original rubber round again. Letting the rollers soak for a minute or so in hot water (around 80 degrees C - water just off the boil) and then rolling them between two wooden surfaces worked reasonably. Note that the old rubber will give off black, best use cast-off bits of wood. Fixed with cold water, then sanded off what remained of the ridges and make smooth with fine-grade waterproof sandpaper. Not perfect, but round enough to roll. (Oddly the brass core in the rear-rollers is not always concentric to the hole, so when building up with heat-shrink can give slightly eccentric rollers.)

The platen was rock-hard and brittle. First tried to find a suitable length of radiator tube (and failed - right size but not smooth on outside), then settled on trying the inner-tube treatment (inspired by a.o. Scott's recent post on this).

A nice, soft, used inner-tube for a bicycle of 28" x 1 5/8" x 1 3/8" was found. From a reputable make (Vredestein) and fairly large in diameter for the size it has a wall thickness of about 0.9 mm. The platen is such a tight fit in the carriage and paper-tray, that the platen needs to be reduced to less than 28mm in diameter for the covered platen to still fit. This is a black and messy job. Best done outside. Not near any laundry. Wear a boiler suit :-)

Using emery cloth and the platen firmly clamped in the workbench got it to size finally (and still cylindrical). Using the hairdryer to make the length of tubing warm (around 50 to 60 degrees C) and supple, it slides on fairly easily using talcum powder on the platen. (A good thing too; after the first full carriage re-assembly had to take it all off again to sand down further to about 27.5mm diameter.)

The hard part of the carriage was the complex left side bracket assembly. The line-feed clasp is fairly easy to place, but the spring to return the carriage return lever was not all that obvious. This is held in place by its own small bracket that is held under a nut that goes on one of the screws that hold the left carriage bracket (red arrow). After bolting it down, the loop of the spring can be hooked over the rod of the carriage return lever that sticks through to the inside (blue arrow). This rod also goes into the fork of the line-feed clamp that pulls the platen linespace ratchet wheel.

When mounting the margin bar, take care that the small spring rod goes on top of the bar in the left edge (green arrow).

By the way, the paper release lever goes back in quite easily. Fixing the cast 'anvil' block with its two screws under the carriage baseplate will hold the lever in place during assembly. Pushing the anvil block to the rear a bit and then fix, gives the paper release lever enough leverage to lift the rollers. When the margin bar is fitted again to the right side bracket, the paper release lever is fully locked in place.

(Proper way to remove the platen is probably not to remove the right-side carriage bracket as I did, but remove the knob and pull out the rod or some such. The carriage knob screw however is rusted solid. Did not dare to force it and risk breaking the knob. Right-side bracket was less puzzling but also a pain to screw back. Can be done with magnetized screwdriver to place the nut back over the screw. If you ever get there yourself, you'll see what I mean :-)

The carriage now fully assembled again. The carriage linefeed feeds paper. The return lever springs back forward. The paper release actually makes it let go of paper. Linefeed release works. Most parts cleaner, return lever polished and even shiny again. Ready for mounting on the machine.


This will all probably make a professional typewriter repairman cringe, but it's getting there and really is an enjoyable journey of discovery :-)

Friday, September 19, 2014

A couple of screws too far

And it all came unhinged :)

Well, not quite that bad, but there were a few parts that could have been left on. The two screws at the back of the carriage hold the bracket of the paper release lever. Removing those screws yields the paper release lever and rod.

Didn't have to come off, but will be able to give it a good clean now.

Having looked at the way it seems to be put together, started off by trying to loosen the carriage bearings to see if that would allow it to come off. The rear bearing rail is held by the four screws circled in the picture. Just loosening these a turn, the carriage bearing can be adjusted. These were very solid, took oil and a few taps with a small hammer to loosen them.

This does give the carriage play, but does not allow it to come off. If the carriage goes sluggish or blocks somewhere along its travel, adjusting such a rail may help. Maybe not necessary to loosen this when sliding off the carriage, but will make it easier to slide off and on again.

Spending some more time to look at where the carriage is held revealed a painfully obvious stop-screw in plain sight. On both ends of the carriage base that is fixed to the machine there is a small stop-screw. These screws stop a small stud in the centre bottom of the moving carriage base.

A bit embarrassed, removed that screw and the carriage slides off easily revealing the two sets of bearings. The front and rear bearings are held nicely in a cage with a sprocket that ensures they stay in situ.

With the carriage off, it becomes more practical to finally get at the feed rollers. Looking more closely again at the paper-tray, this is impossible to remove by unscrewing the brackets. The paper tray is right on top of the screws that hold the brackets to the carriage base. As far as I can tell the only way this can have been assembled is by holding it all down in a jig and then insert the rod in the hinge. (Moments to wish a typewriter repair shop was nearby. Or even not-nearby for that matter :-)

Oh, the two screws underneath the centre of the carriage base hold a small cast block that holds the spring wires that provide the clamping force for the feed rollers. (These also did not have to be loosened...  Oh well, discoveries.)

With better access, it is however possible to carefully bend open a little the folded lips that hold the feed roller axles. With the eyelet lips bent open just a bit it becomes possible to use pliers to pull out the rods and get at the rollers.

To keep them in, one end of the rods is knurled. This knurled end is press-fitted into its lip during assembly to keep it in place firm. The front feed-roller rods were applied from the outsides, so can be pulled outward. The rear feed-roller rods (in the bogies) are identical sub assemblies that were probably fitted to the carriage already assembled. So the left rear rod should have been pulled to the right and not left through the rollers...

Got them all out now to be made round again. Most rusted parts of the carriage are now also accessible to give them a good clean and shine.

Progress :-)

Wednesday, September 17, 2014


Have started on the Remington Portable 2 - first step of taking it apart. Well, at least as far apart as is necessary to replace the feed rollers, touch-up the housing shells, replace felt, deep clean etc. Putting a rubber tube on the platen would also be good.

Taking off the shells was fairly straightforward (taking pictures every step of the way, bagging every screw and part).

How to get at the feed rollers has me stumped for now though. Removing the paper table should ideally be possible without taking the carriage off the rails. As far as I can see the paper table assembly is screwed to the carriage base with a screw that is underneath the paper table itself.

It was the putting together again that I was initially worried about, but just taking it apart is puzzling already :-)

Any hints or suggestions most welcome. It's an intriguing puzzle...

Wednesday, September 10, 2014

Graphoplex No 612

Prompted by the posting about a book on sliderules over at, made a scan of the leaflet that came with a pocket sliderule I got recently.

It is a regular 'Rietz', but rather small with a 12.5 cm scale. This one looks and feels absolutely new and unused, the leather sleeve is pristine as well. The only marking on the back indicates it was intended for Heemaf, either for use by the company or perhaps more likely meant as a promotional gift. The overall look and feel makes me guess this could be as recent as the seventies, but hard to tell really.

In the small leather sleeve with the small sliderule comes one sheet of instructions folded up equally small. A very condensed course in using this system 'Rietz' sliderule (in Dutch).

Friday, September 5, 2014

Corona care

Actually an easy and relaxing little task to do. Most time is taken by locating the part from the diagram on the machine itself. Did have a positive impact on the smoothness of the carriage.

(The manual for this model of the Corona 3 folding typewriter is online on the Archive.)

Monday, September 1, 2014


Spotted as a decoration piece in the lounge / dining-room of a hostel. The small flowers are plastic, lending it all a solemn yet sadly cheap air.

Despite the artificial floral surroundings, the machine still looks solid and reassuringly metal. Some faded keys had paper labels with the letter written on them by hand, suggesting some use when already worn and faded. Did not dare touch or tamper with it, but its current state with keys all a jumble suggests misuse rather than use. The paint looked a bit 'cloudy', as if it's been chemically attacked by something. Two metal Olivetti spools.