A Close Call

I happened to be in our shop for a few minutes, standing at the desk, when I saw what at first I thought to be a bit of cat hair floating around the top of the computer that sits on the desk.

I quickly realized that it was smoke so I immediately unplugged the power cord from the rear of the computer. This is a medium tower enclosure and it was sideways, against the wall at the back of the desk so the power plug was readily reachable.

After a few moments, the smoke did not stop, so I cleared the stuff from the top of the computer cabinet: a box of tissues, some papers, and a couple of polyethylene bags. Well, the bags had melted and stuck to the top of the computer case:

The smoke did not seem to be abating, so I removed the side cover. This was again easy because of the position of the computer. At the very top of the case, there was a small flame burning, so I blew it out.

The source of the fire was the SATA power cable adapter on the DVD drive. This had somehow shorted out and started burning, also destroying the DVD drive and its SATA data cable.

Fortunately, the drive was in the top bay so the soot from the fire did not enter the rest of the computer. However, the heat from the shorted wiring set the soundproofing lining of the top of the case on fire. This is what was burning when I opened the case.

Burnt soundproofing, seen through the DVD drive bay opening

Burnt soundproofing liner, seen from the side

Once I removed the DVD and wiped up most of the soot, the computer powered up and ran fine. We don’t use the DVD at all so that is no great loss.

I have to wonder, though, what would have happened if I hadn’t been there to notice the smoke. Would the fire have gone out on its own (though possibly destroying the computer), or would the stuff on top of the computer caught fire?

This is the second incident I’ve run into with a SATA power cable overheating where it plugs into the drive. The previous incident was just a flash and pop, damaging the drive terminals a bit (but not beyond usability). This time my assumption is that a bad connection to the DVD initially caused the terminals to heat up a bit, thus making the connection deteriorate a bit, leading to more heating, and so on, until there was enough heat to melt insulation and allow the wires to touch, starting the fire. I would not expect an idle DVD drive to draw enough current to start such a chain of events but apparently it is.

The amount of current drawn by the shorted wires was not enough to shut down the power supply, another event which could have saved things. Unfortunately computer power supplies only monitor the overall current, and not the current to the individual power connectors, thus making them able to easily overload the wires on one power connector without shutting down.

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Wither Workshops?

Because of the COVID-19 pandemic, we’ve had to suspend all of our workshops since early this spring. This was particularly disappointing because we had one planned for just then with plenty of participants.

You may be wondering when we will restart our workshops, now that the pandemic is easing a bit (at least locally).

We will not be planning any general workshops until the COVID situation clears up further, beyond the current stage 3 protocols. We don’t have enough space in our workshop to assure isolation between participants, and it is also the nature of these workshops to share equipment and materials amongst participants which further impairs any isolation attempts. This essentially means open workshops will remain suspended indefinitely.

However, we can offer workshops on a one-on-one basis, or to groups who are in the same household/bubble and so are already in close contact. The one-on-one workshops would unfortunately cost more and would be a bit less fun because of the lack of conversation with other participants. For a group workshop, you would have to organize your own group. Under current protocols, all participants (as well as us) would have to wear masks for the duration of the workshop.

If you want a one-on-one workshop or can organize an appropriate group please get in touch with us and we’ll see if we can arrange a date.

A Home-made Monotype Display Mould Coupling Hook

The Monotype caster type carrier not only catches the type as it ejects from the mould and carries it to the type channel for final delivery, but it also moves the mould crossblock between its casting position and its jet-eject position.

A coupling hook on the crossblock provides the linkage between the crossblock and the end of the type carrier. The carrier itself operates in one of three positions: The standard position is for type up to 12 (13? 14?) point to be delivered in lines to the galley via the straight type channel. The second position is for casting loose display type: It offsets the type carrier about 12 points to the right so it can receive the wider type as it ejects from the mould, but it also delivers the type about 12 points to the right at the type channel so it must be used with the curved display type channel. The third position is for large composition and has increase stroke so the right end of the motion can accommodate the wider type while the left position still aligns with the straight type channel for galley delivery.

This third position can also be used with the display moulds (as opposed to large comp moulds) except for one problem: To account for the offset second position of the type carrier, display moulds have a slightly shorter crossblock. If you try to use them with the third position of the type carrier, the machine will cast type but you’ll have quality problems because the jet, where the molten metal enters the mould cavity, will not be aligned with the pump nozzle and so there will be a lot of turbulence filling the mould.

To address this problem Monotype produced a special display mould coupling hook, part code 50B1, which shifts the mould crossblock a bit so the jet is properly positioned. These parts seem to be impossible to find so after several years of looking, I finally made myself a couple of them:

Two home-made display coupling hooks alongside the standard hook (right)

Here are the two hooks installed in display moulds along with a third mould fitted with the standard hook (left):Even though I had carefully measured the standard hook and extrapolated the shape of the display hook, the parts I made still did not quite fit onto the moulds. It turns out there is some sample-to-sample variation in the standard hooks and the one I had started with was at the large end of the range of variability, so I had to adjust my parts a bit. Even the standard hooks are not 100% interchangeable between moulds.

I made these from an offcut of D2 tool steel I had kicking around. If I wanted to I could have these heat-treated to harden them, but the steel even in its annealed state is still pretty tough and should be able to last through what little use it may see. The steel piece I started with was just barely big enough so the underside of one of the hooks actually has a dimple in it from a drill hole that I couldn’t quite machine out.

My caster is currently partially fitted for strip casting so I haven’t been able to try these hooks in action yet.

Pigment Retention at Work

I recently ran a series of pigment strength tests to compare our current stock with a sample from a supplier, and as I was preparing each sample I noticed that I could see the retention effect of our liquid sizing at work.

Because I’m just comparing one pigment to another at various dosages, I don’t use any retention agent for these tests, but instead rely on the mild retention effect supplied by our liquid internal sizing. This product is an emulsion of droplets of a waxy material in water, and these droplets are deliberately made cationic (with a positive surface charge) so they bind well to the paper fibres which are anionic (with a negative surface charge). A side effect of this is that the emulsion droplets also bind to the pigment (also anionic) and so acts as a bridging retention agent.

The effect can be seen by the appearance of the pulp sample before and after stirring in the sizing.

Before sizing was added

Note how the pulp that is right at the surface appears very white, while the liquid is quite cloudy with pigment. You can really only see the pulp fibres that are very near the surface.

After stirring in the sizing

Once the sizing has been added you can see two effects: One is that the pulp fibres themselves have taken on the pigment and are no longer so white. The other is that the liquid is much clearer than it was: you can actually see pulp fibres through the deeper water.

This is by no means perfect retention; if it were, the water would be completely clear. However, this does illustrate the effect of retention on the pigments. Clear water in the pulp indicates good retention.

Mystery Matcase Solved!

Thanks to Mark K. Digre on the Letterpress mailing list, I think the mystery of the strangely-sized cellular matrices has been solved!

The mechanism for using this matcase is described in US patent number 1079321. Essentially, the caster is fitted with longer locking racks which extend beyond the airpin blocks to the rear and to the left of the caster. The extensions on the racks have teeth and locking dogs which correspond to the 0.3″ spacing of the oddball matrices. Pneumatic cylinders are used to set these locking dogs, and also to suppress the standard mechanically-operated dogs, and the air for this is timed by a valve operated by a supplementary cam on the main camshaft.

A manual valve either leaves this system completely off, for normal casting, or allows air to the pneumatics for the front airpin block. The position of the front jaws then determines whether the rear airpin block uses the standard or modified locking dog, thus providing for the different spacing of the bottom three rows of matrices in the matcase.

Overall the system appears rather awkward, and the new racks and locking dogs would be subject to a lot of wear since each time they lock, they would have to move the rack up to 0.1″ from the standard position selected by the airpin to the 0.3″ grid location, against the force supplied by the Pin Jaw Tongs Spring (57E) and the Jaw Tongs Spring Box (26E).

At least this was an improvement over US patent number 1094678, which fitted the back of the matcase with extended cones to catch the centering pin even when grossly mispositioned and drag the matcase to the correct location. This system required the cone holes to not be on the 0.3″ grid because that would put the standard grid locations too far from the desired locations and the centering pin would not be able reach the cone hole, even these grossly enlarged ones. As a result, the cone holes were off center in the mats which meant in turn that the mats could not be so freely repositioned in the matcase. This system would cause a great deal of wear to the centering pin and the cone holes of the mats, because this final positioning would be pulling against the Jaw Tongs Spring Box (26E).

More Matcase Storage

Over the past year or so I’ve purchased more composition matrices and so far they’ve been sitting on the floor, in the way, in the boxes they were shipped in.

The top four are the new ones

Last week I made four more cases to hold them, to match the 7 cases I already had, for a total of 11 cases each capable of holding 24 matcases. For lack of a better location, I just placed them on top of some of the older cases, and promptly filled over half of them.

Yes, I got one of the partitions installed backwards. So sue me.

These matcases are still only identified by which case slot they are placed in. The actual markings on the cases are somewhat random based on where they came from. I think what I will be doing is placing my own serial number on each matcase, and recording on the computer what faces are in each case, along with the arrangement used.

Many of the new matcases have only a single font loaded into them. This is particular true for faces like the Gothic faces which do not include small caps or italics, so there are only two alphabets (uppercase and lowercase), one set of figures, and points, or around 72-80 matrices. The remainder of these matcases are filled with junk matrices: cellular mats for fonts that are too small or too worn out to be useful. You can leave an empty position in a matcase but if you accidentally try to cast that position in the matcase, you get a real mess of a squirt to clean up in the caster, so filling with mats—any mats—is well advised. As I was loading these matcases into the storage cases I was wondering if these junk mats actually held any treasures…

I have a few empty matcases around, and a few fonts of cellular mats that are just in boxes, so I may be loading a few more matcases later.

Updated Typeface List

Our list of faces that we can cast has been updated to include the composition matrices we have acquired over the past year or so. Unfortunately, I still don’t have the computer control for the caster running, so I still can’t cast composed type. However, all the typefaces are also available as fonts for handsetting. So if you want a font of 5-point Modern, you’re in luck (assuming I can get a disused 5-point mould to work).

Mystery Monotype Matcase

I have a matcase for Monotype composition casting that is a bit of a mystery to me.

Some of it is easy to figure out: This case contains 14-point 175A Bodoni and 14-point 79J Caslon Bold (with french accents). I found this by disassembling the case and inspecting the markings on the individual matrices. This is a Lanston-style case with the “combs” to separate the matrices rather than the English style case with the rods and perforated plates.The unusual feature is the size and spacing of the individual matrices: The mats are 0.2×0.3″ and 0.3×0.3″ and anyone at all familiar with Monotype composition casters will know that the matrices should be all positioned on a 0.2″ grid. The caster can only position the matcase at multiples of 0.2″ and so would not be able to position to every second row in this matcase, nor to any second column in the bottom three rows.

The benefit is the ability to have two full upper/lowercase alphabets, which is not possible using the standard Large Composition matcase layouts (used for sizes over 13 point). Large Comp uses mats that are double-width and/or double-height and so fitting even a single alphabet, figures, and points, is tight.

I had thought that one would need a caster fitted with custom airpin blocks, with the airpins spaced 0.3″ apart, and locking racks to match. You could kludge the Unit Shift mechanism (making it shift 0.1″ instead of the usual 0.2″ with customized matrix jaws) to avoid needing a custom front pin block. But then further thought reveals that the rear pin block needs not only the standard 0.2″-spaced positions (for the top 7 rows in the case) but also the 0.3″-spaced positions (for the bottom 3 rows). So the rear pin block would need 20 addressable positions with somewhat staccato spacing. Getting that many airpins in there may be possible, but then what ribbon punch combinations would address these (the normal punch combinations can address 17 positions)?

And of course, the easy bit, the normal wedge would need to be made with only ten positions corresponding to the ten rows in the matcase.

The wear on the rear cover of this case indicates that it has been used. So does anyone have any useful observations on this? Is this some experiment that escaped the development lab? Or was some Monotype client big enough to afford all the caster customizations required to make this work?

Walnut Ink Shrinkage

Several years ago I made a batch of walnut ink. We’ve had a 500ml bottle of this sitting near our desk since then.

Over the years the bottle has collapsed from a vacuum forming inside, and I finally decided to vent this bottle. Once I opened it, and carefully squeezed the sides of the bottle to expand it back to its original round shape, I found that almost half the contents had vanished.

We had a few smaller bottles of this ink as well, and they also collapsed like this.

You might think that this is due to water somehow escaping from the bottle, but we use these bottles for several water-based products, and we have not seen this much shrinkage in those.

The only other conclusion is that the ink is undergoing some transformation which causes it to actually absorb the water chemically. This would probably be a hydrolysis reaction where a chemical bond breaks and a pair of hydrogen and hydroxyl ions attach themselves to the loose ends.

But then I weighed the bottle and it weighs about 320g, consistent with the weight of a 500ml bottle half-full of a mostly-water substance. So I suppose this is just water loss through the bottle and cap seal after all. If the water had been absorbed chemically, the weight should have been around 550g (500 g ink plus some allowance for the bottle).

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What was lost is now found!

Ever since the ATF conference in Salem MA in August 2014, I’ve been looking for the 49A matrix holder which I had brought to the conference to show around. This is a holder for using Lanston display matrices with the English display moulds. This holder was interesting insofar as it had a failed attempt, from the factory, to repair a casting defect, leaving the tip of a tap broken off in the body of the holder.

Well, I’ve found it again:

Proof positive that this is the same holder, I removed the cover and verified that the broken tap was there:

The red arrow points to the broken tap. They were attempting to repair that hole in the casting visible just above the tap. It appears that they decided that the hole was not critical and gave up repairing it.

So where has it been for the past six years? It was in a crate of keyboard spare parts! I had brought this crate along with me to the conference for the swap meet, and it seems that after showing the mat holder around it ended up in this crate when I packed up.

It turned up this week when I was rummaging through all my spare parts looking for anything related to casting strip material on the composition caster.

So far, I can’t cast strip material because the strip casting moulds use a different pump (the nozzle has a different location). The strip-casting pump I have is a Lanston pump, and my caster is an English one so the pump will not fit. The Lanston pumps are wider where the levers that operate them run. In order to use this pump (and any other Lanston pumps, of which I have several), I need Lanston versions of the pump levers with part codes 18H and 24H.

I’m also missing several pieces of the linkage that operates the mould blade for the strip moulds, but I should be able to make my own parts for this. But the pump levers are castings that I can’t reproduce easily.

In the meantime I’d received another 49A holder from Rich Hopkins, but it is always nice to have a mystery solved!

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