First try at strip casting

I have my Monotype composition caster converted to produce strip material—leading and rule—and this is my first try at running this setup. You can see the inauspicious results in my accompanying YouTube video.

I am using a pump body which I got from Rich Hopkins, with its nozzle specially positioned to mate with the strip material moulds. The piston was from my own parts stock, and I had to make the special nozzle for use with the strip material mould. The levers which operate the pump were given to me by Ed Rayher from Swamp Press. I needed these because the pump body dimensions are different for Lanston (American-made) and English-made pumps and the only levers I has were for English pumps (as my caster is an English one).

I had a few other odds and ends from my parts stock: The stroke adjustment mechanism, one of the levers that operates the mould blade, and the adapter that connects the centering pin arm to the clamp lever on the side of the mould. The rest I had to make: various push-rods, levers, linkages, a spring box, and a base to provide mounting points for everything.

In this video I have everything put together and trying to cast some 3-point low leading. It sort of works, but it is not filling the mould properly, the casts are not fusing to each other properly, and the casting keeps jamming where the trimmer blade is removing the side jet from the strip.

My mould has a two-part trimmer setup. One knife cuts close to the side of the strip to remove all traces of the jet. Another curved piece before this knife seems to be intended to break off most of the jet but I’m finding that it just jams on the cut-off jet material. At that point the strip stops advancing and the spring box compresses since the mould blade can’t advance. My copy of The Monotype Casting Machine Manual doesn’t show this second cutter so I’m not sure what to do with it.

Well, it turned out that I had this installed on the wrong screw. There are two screws holding the trimming knife in place, and this should be mounted on the screw to the right. Once mounted here this part becomes a smooth extension to the knife, ensuring that any cut-off jet gets pushed down back into the pot to be remelted.

The jet deflector, properly installed.

This deflector may not serve much purpose. I don’t see it mentioned in the manual, and I only have one on my 3-point mould, not the other two moulds. This is probably used when you are also using the guide tube which supports the cast strip as it crosses above the pot on its way to the stacker. When there is no guide tube the regular trimmer blade should deflect the jet down enough to not cause problems, but with the guide tube in place this extra deflector might be needed to force the jet quickly into the pot so it doesn’t butt up against the end of the guide tube.

I’m hoping a bit more tuning will get me casting solid and properly-fused strip material. Then I’ll try out the other two strip moulds I have (2-point and 6-point) and maybe play with casting some rule. I have several rule matrices but I can’t use them with the 3-point mould because I don’t have the “high” mould blade for it.

For my test I had the blade stroke stop set for its short-stroke position, used for ½″ stroke when casting rule. When I repositioned it for a ¾″ stroke (which can only be used for casting leading, not rule) I found that my spring box wasn’t compressing at both ends of its stroke. It would appear that I’ll have to alter my linkage a bit to change its lever arm ratio to provide a tiny bit more stroke. I’m hoping I can do this just by drilling a new hole in one end of the first lever; this is fine if the hole moves far enough (more than its own diameter) but for a smaller shift, I’d have to either weld the old holes closed or make a brand new lever.

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A novel motorcycle air filter (not!)

We’ve had a week of beautiful warm (for November) weather here and I took advantage of this to take my motorcycle (a 1987 Kawasaki EX500) out on several rides. Unfortunately on the last ride the bike decided that it wouldn’t idle unless I constantly blipped the throttle. If I released the throttle the engine would go to idle speed but then over a few seconds gradually slow down and stall. Restarting the engine required opening the throttle a bit, something I don’t normally have to do.

This is a symptom of the pilot (idle) system in the carburetor not working properly. This system supplies the fuel needed to run the engine at idle, when the throttle is completely closed.

To fix this I had to remove the carburetors to clean them and one of the first steps is to remove the air filter. They don’t make that easy: I had to remove the fuel tank (including disconnecting its hoses) and the fuel tank bracket. Once I removed the air filter cover this is what I saw:

The airbox was almost completely filled with what was probably a mouse nest, containing a mix of fibreglass insulation (mice love that stuff), shredded paper, sunflower seeds, acorns, and other junk. The foam element of the air filter was completely gone.

I’m not sure how long this has been this way; it could have been fairly new, or it may have been like this for years.

To get this cleaned out I had to remove the airbox completely, disassemble it, and wash everything out.

I also removed and cleaned the carbs, and now have things partly reassembled. The engine will idle now, but only with the idle speed turned up a bit. I don’t have the replacement filter yet (it is due later this week) so that might be affecting things a bit.

As it turns out removing the air filter is one of the few things I didn’t actually have to do to remove the carbs. But I did have to remove the side covers of the airbox so it would be able to lift up a bit. Taking those off would have revealed the mouse nest as well.

But now the nice weather is coming to an end so I probably won’t ride again until spring.

Trying out the New Nozzle and Strip Mould

I installed the nozzle I just made into the special strip-casting pump. This pump is a Lanston (American Monotype) pump and my caster is an English-made one, and one of the incompatibilities between these is the pump body size. Although you can’t interchange the pumps directly, it turns out you can interchange the pumps as long as you also interchange the large levers that operate the pump.

With the new nozzle installed I placed the strip-casting pump into my Monotype caster. At first things just seemed wonky. I could not seem to crank the pot up all the way, and the pump mechanism was operating whether engaged or not. It turned out I had installed the lower pump operating lever upside down and on raising the pot this was actually lifting the pump operating rod and crossblocks. Inverting the lever allowed the pot to raise properly and the pump operated properly.

I’m working on cobbling together the linkage to operate the strip mould but it is not complete yet.

I have however been able to operate the caster manually, turning it over one cycle to fill the mould cavity, then manually ejecting the cast metal, and repeating. Here is the result of that effort:

Admittedly that’s pretty rough, but then the mould was cold and the caster was stumbling along at whatever speed I could turn it over by hand, so I think that’s pretty good!

Home-made Monotype Nozzle

I’ve been working to get my Monotype composition caster converted to casting strip material. I have a few moulds for this, the special pump required (with a different nozzle location), the pump linkage required to run this Lanston (American) pump on my Monotype Corporation (English) caster, and other odd parts of the linkage required for the strip mould. I also have the cutting and stacking attachment, but it is a mass of rust right now. I’ve been making the missing parts from the mould operating linkage and as that job is nearing completion it was time to get the mould and pump combination working.

In addition to needing a special pump, the strip casting moulds also require a special nozzle, which is what actually injects the molten type metal into the mould cavity. These aren’t available new any more, and the strip casting attachment was already a bit of a rare bird, so accessories such as the special nozzle are doubly rare.

There is a drawing out of Monotype Corp., of which various Monotype owners have a copy. It is drawing number DB431 and shows 23 different nozzles with their specific dimensions and uses. This drawing is incomplete in a sense, though, as it only gives dimensions for the features of the nozzles that differ from one to the next. The threaded base, taper of the conical tip, and size of the little extension tip that some of the nozzles have are not dimensioned at all on this drawing. As a result I had to determine some of these dimensions myself from nozzles I already had, and take good guesses at some other not-too-critical dimensions.

With that information in hand, I made myself a No. 11 nozzle (#14741, for 4-10 point and didot lead, rule, and borders, mould series 76300). Here it is:

This particular nozzle calls for an 18° conical flare inside the tip:

You just can’t buy 18° conical endmills, and even something close (20°) is very expensive, so I shaped the cone using a tiny boring bar mounted on the compound slide of my lathe. I made this from the broken stub of a tiny drill. I thought it was carbide, but the drill bit didn’t really grind like I would expect carbide to, so perhaps it is tool steel.

My makeshift boring tool. For reference, the shank where it goes into the collar is 1/8″ (3mm) in diameter.

The nozzle didn’t quite fit in the pump body, so I had to shorten the stem a bit and cut one turn off the end of the threads, but now it fits nicely and I’ll be modifying my drawing to match.

The next task is to test how it works.

Vandercook SP-15 parts for sale (Sold!)

Update: The lockup bar has sold, but all the remaining parts are still available.

Second update: Everything has been sold. The lockup bar garnered plenty of interest.

I have a collection of random parts from an Vandercook SP-15 proof press for sale. I don’t have them individually identified, but the photos should be clear enough for you to see what’s there.

I would prefer to sell the parts as a lot; they should be of interest to someone who regularly services these presses. I might be willing to sell the lockup bar separately, though.

I’m not sure how much to charge, so feel free to make an offer.

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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).

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