The first job was to address the problem of the magnetic starter tripping out every few lines. I found online several documents regarding the pulsing nature of the current drawn on the input of a VFD. I think the pulsing current may be fooling the current sensor on the magnetic starter, making it signal an overload and turn off the power. In the manual for the VFD they provide recommendations for input wiring protection based on the capacity of the VFD rather than that of the motor. By following these recommendations I set the current limit on the magnetic starter to a higher value, and as a result the power did not shut off at all during today’s work.

For reference of what it is I’m trying to cast, here is the proof I took at Mono U of the caster output from my ribbon after hand corrections:

This is cast in 9 point Times Roman on a 10 point body, with 3-point leading between the lines. Although the lines were supposed to be justified, due to the keyboarding errors and manual corrections, only three of the 8 lines that should be justified actually are (“1. Select the location…”, “2. When you click…”, and “also be options for fixed…”). My corrections to the ribbon should improve that average a bit.

The third line, once corrected, was actually too long so part of the hand correction was to hyphenate the word “pointing.”

By the way, the text is a short excerpt from the documentation for a computer program for managing digital Matrix Case Arrangements (MCA’s).

Sunday afternoon, I tried casting the ribbon again. One thing I noticed about the line lengths was that the lines that were quadded out at the ends of the paragraphs seemed to have more accurate line lengths. There was one adjustment I had not done on the caster, which is to adjust the space transfer wedge so that types cast with the S punch in 3/8 justification come out the same width as the same types with no S punch. I manually punched a ribbon to set 3/8 justification and cast a series of em quads. By running this ribbon and stopping it after it got to the quads I could cast a line of justified em quads, then disconnect the air supply and cast a line of non-justified em quads for reference. The justified ones were casting wider than the non-justified ones, but by adjusting the transfer wedge I got these to cast the same width.

Later that afternoon, with a bit of futzing about, adjusting line lengths as the caster was running, I got the ribbon to cast at one go with no freezes and no motor cutouts. I did have one line break not work, and by the time I noticed there was most of the next line in the type channel. I stopped the caster and carefully removed the first line and set it aside. Later I integrated it into its proper place in the form. There were a few small blobs of metal under some of the types in the earlier lines (near the bottom of the form). Perhaps these were caused by bleeding feet on the type. In any case, here is the result, with some of the spacing adjusted to fill the lines more or less:

I made a list of all the errors, and reviewed the ribbon to see if they were keyboarding errors or casting errors. In the latter case I compared what was cast with what the ribbon called for to try to determine if the error was a hole not read, a hole read where there was none, or some other more complex error. Most were of the first type, which might be corrected by increasing the air pressure.

To address the problem of incorrect line lengths, I made up another Excel spreadsheet to calculate the proper justification codes for a line on the ribbon. You enter the set size and line length once, and for each line, you enter the number of S punches (which are adjustable-width characters), the number of 1 punches through 14 punches, and the number of rows on the ribbon with none of 1 through 14 punched (which selects row 15 in the mat case). The spreadsheet then calculates for each line the two justification codes required.

I found several of the lines were way off, usually due to some other mispunch on the line. For instance, there is one place where two letters were punched in the same row of the ribbon, because the ribbon did not advance in the keyboard. This will only cast one type (by 25% chance it is actually one of the punched letters), but the keyboard counted both of them when calculating its justification. I corrected these justification errors using tape and the hand punch.

In the evening I ran the ribbon again, with even better results. The line lengths were fairly even (though not perfect). Only one line ended up too long, due to one type casting as an em quad instead of a narrower letter. Other than that all the lines fed onto the galley with no problems. Turning up the air pressure a bit had reduced the number of miscasts.

I haven’t taken a proof of this yet. That loose “g” at the end of the fifth line actually belongs at the end of the third line on the word “pointing.” This is also the line that cast too long; you can see the rogue quad at the start of the line between the words “on” and “the.”

After checking the errors against the ribbon again, I tried to cast the form a second time, but started getting nozzle freezes. The clutch that drives my caster may be slipping a bit as it warms up, and as a result the RPMs drop and freezes can occur easier. I was also getting late so I quit for the evening.

This morning I checked the angular alignment of the nozzle on my caster and found that it was off a tiny bit, so I adjusted that. I also reset the nozzle to its proper center position on the assumption that the faulty alignment was causing the leakage.

I also took apart my mould again, including removing the two side blocks on the crossblock and the two type blocks on the main body of the mould. I cleaned off some accumulations of well-adhered type metal, and on reassembly I took great care to ensure that the mating surfaces were absolutely clean and free of oil.

I put everything back on the caster, and tried it out. It was casting beautiful quads with no sign of nozzle freeze. But looking at the nozzle area revealed why: The nozzle was leaking plenty of type metal, and all this extra flow was keeping the nozzle hot.

I lowered the pot and swung it out, and gave the outside of the nozzle a good cleaning and examination.

A close look revealed that there was something off-center or out of round, perhaps as a result of being used too much with the centering position out of adjustment.

Unfortunately the only spare I had (aside from the display casting nozzle) was in even worse shape. It looked like someone had pinched its tip with pliers!

I have a factory drawing of the dimensions of several nozzles so I knew what shape the tip should have. I didn’t have much to lose in trying to reshape these nozzles, so I started with the pinched one. I mounted it in my lathe, carefully centered it, and turned a thin cut off the conical end until the pinched area was gone. Then I cut the slight step in the shape and drilled out the hole to 0.070″ per the diagram. Finally I used a file to cut the tip down until there was a flat spot 0.093″ in diameter.

I put this on the caster and readjusted the nozzle height. This nozzle did not seem to screw in quite all the way so despite me shortening it, I actually had to lower the nozzle height so it would seat at the right time.

After casting a couple of lines of quads the mould was warmed up and ran with no freezes, and, even better, no nozzle leakage! Furthermore it was clear the mould was running tighter because the cast of the air vent on the jet had almost no flash on it, unlike previous times.

One other problem I had encountered last weekend was the casting of letters directly above the correct ones in the matcase (and also the line length being wrong as a result). I though it might be due to excessive air leakage between the pins, but reducing the air pressure had not helped. However, during the week, while I was working on one of the other problems I noticed that the front pin jaws were not closing fully around the air pin. In fact they stayed far enough open that the rack might be more than half a tooth out of position, so when the locking bar seats it actually pushes the rack to the next position from where it should have been. I traced the open jaws to the rod that connects the tongs spring box to the bell crank. A nut had come loose on this rod so the rod had some end play. When the rod was pushed by the spring box (which closes the pin jaws) it would not push far enough. I tightened the nut and thing were running properly again. Quieter too because the rack was not making any “clack” noises as it was snapped into position by the locking bar.

I tried casting the ribbon again. At first the galley was not operating when it should. It seemed that the air pins for the two justification lines had become a bit lazy so I turned up the air pressure a bit and they started working properly. I got through a run of the ribbon with only a few events: The line lengths are still all over the map so I had to stop to clear over-long lines and spend time dropping quads into the too-short lines. I had a couple of lines where the column pusher did not push far enough (instead compressing its spring box). There were also some miscasts too, often involving a position on the ribbon reading holes from adjacent positions. Perhaps I turned the pressure up too much in my effort to get the line breaks working.

Finally I still have the problem of the magnetic starter that supplies the VFD tripping its overload protection after casting 4 lines or so. The average current draw isn’t actually that high, but because the VFD is converting the supply to DC using a simple bridge rectifier and capacitors, the peak current is actually quite high but only occurs for a small fraction of each AC cycle. This spike current might be spoofing the overload sensing on the starter. Because the VFD itself provides overload protection for the motor, all I really need is a switch and over current protection (fuses or a circuit breaker) rather than the magnetic starter. For now I’ve turned up the overload limit on the starter so I hope this will stop these false trips.

Last Sunday was another frustrating day of casting.

The only way I could get the nozzle to seal even remotely well was to have it clearly out of alignment, so it was moving sideways every time it rose and dropped. This is not good for the nozzle, since it tends to wear a flat spot onto it. It also means the nozzle is in contact with the mould longer than it should be, leading to a greater likelihood of nozzle freezes.

And I got nozzle freezes aplenty! I could not get an entire line cast without the casting stopping partway through from a nozzle freeze.

I had adjusted the nozzle height and pump timing according to the directions in Casting Machine Adjustments but I found that the resulting setting seemed to leave a lot of dead time between the seating of the nozzle and the start of the piston stroke. Furthermore, when I swung the pot open, I found that the pump would sort of pop out of its operating levers much more forcefully that it did when I was casting a couple of years ago. I have since found a different procedure in ‘Monotype’ Casting Machine Manual which gives a more sensible adjustment.

It would appear that between the publishing of these two books (1920’s and 1960’s) the linkage to the pump had been redesigned so that the pump castings would not be overstressed by the mechanism trying to lift the piston too far on the return stroke. Applying the old directions left most of the play in the linkage to be taken up before the piston moved.

Although it is newer and accounts for changes to the machinery over 40 years, ‘Monotype’ Casting Machine Manual still has its share of confusion. In the particular the section on adjusting the pump and nozzle states incorrectly that the force that operates the piston contributes to the force seating the nozzle (adding to the spring that already does that). Because the piston is operated by the opposing force of two levers, this is not possible; the force applied upwards by the pump body lever will exactly equal the downwards force applied by the piston lever (and, through the pressurized metal in the pump cylinder, to the pump body) and so there will be no net force on the pump body.

There was one remaining part of this adjustment that I did this evening: I had to shorten the linkage rod that operates the pump so the idle position of the pump does not quite bottom out the crossheads. This required loosening locknuts at either end of the rod and rotating the rod using a pin wrench in a hole in the middle of the rod. All this done through two openings in the back of the caster not much larger that my hands. The pin wrench is just a little stubby tool which is used to rotate parts such as the mould blade abutment screw (to adjust the width of the type). Unfortunately, the tip of the wrench is quite brittle, and after a couple of turns one of the locknuts bottomed out and the pin wrench snapped off. Both ends of the wrench were now broken so it was pretty much junk, but when it broke off, it just vanished! It fell somewhere under the caster table and so far I’ve been unable to find it. There aren’t many moving parts below the rod I was adjusting so the wrench is unlikely to jam anything, but I’m still impressed at how good a disappearing act it did.

I will probably make my own pin wrench to replace this one (which I got from Rich Hopkins just this summer) and I’ll try to make the tips less brittle, so they bend rather than snap off.

Although I’ve been trying to adjust the nozzle position, I’m wondering if the nozzle alignment (tilt) is off too, and that dragging up one side of the cone hole under the mould is enough to push it into alignment. This would explain why it seals so poorly when it rises freely, but seals better when it is off-center.

I will have to take the mould apart again and clear it of smeared type metal, so while it is off I can check the nozzle alignment. The smeared type metal is partly the result of running the mould too hot (in an effort to stop nozzle freezes).

Sunday evening, I shut off the machine early in my frustration, and spent the rest of the evening patching up the tractor holes on the ribbon. I also repunched the justification codes to correspond to my set size of 10¼ points (the ribbon had originally been punched for 9½ points set). I have a small Excel spreadsheet into which I can enter the original set size, new set size, original line length, and justification punches, and it calculates the new line length and corrected justification punches.

Last Saturday I tried again to do a run of composition casting. At some point, the galley mechanism stopped working, and a very long line developed in the galley.

I stopped casting and looked for the cause of the problem. The justification was still taking place, but when the galley trip rod (a49D) was pushed forward by the justification mechanism it didn’t even touch the galley trip lever.

On the English casters, this trip lever (h45FF) has a graduated adjustable cam (45F29 through 35) to control how far the trip rod has to move before tripping the galley. This allows the setting to be adjusted to compensate for overthrow of the trip rod when the machine is running fast and a single justification is coded in the ribbon, and also allows the switch between using single and double justification to trip the galley. I couldn’t really understand how this could have gone out of adjustment so easily, but I reset the cam position so double justification would trip the galley again.

I started casting again, and the galley tripped properly this time, but partway through its cycle there was an unexpected clunk. At the next line end, the galley did nothing again even tough I saw the trip lever move.

I stopped the machine right away and removed the tool tray to check the galley mechanism. This is what I found:

The post (14F6) that the pawl spring should attach to was snapped off. It seems that halfway through the galley cycle, the galley trip lever had caught this post and snapped it off. This implied that the trip lever was capable of swinging much too close to the axis of the galley cam, so the stop bolt (45F9) was also adjusted wrong.

It was only when I had a closer look at the trip lever and its adjusting cam that I realized the true cause of the original problem. The bolt (45F27) that locks the two pieces of the trip lever (h45F and 45F26) together had loosened and the two ends of the lever had swung out of their proper relative positions. You can actually see the clean spot where the washer should be. Because this had shifted the trip lever was able to swing in and catch on the spring post.

The American casters have a one-piece trip lever, and use an adjustment screw (along with a spacer that swings in & out for single- or double-justification galley trip) to accomplish what the fancy cam on the English machines does. The presence of this two-piece trip lever seems somewhat superfluous to the adjustments provided by the cam and stop bolt. Its only reason for being there seems to be so that the trip lever can be set so position A of the adjustment cam reliably trips the galley with single justification at low speeds. This ensures that the adjustment cam has enough range to work with double-justification galley trip at high speeds.

In any case I re-adjusted the trip lever based on the instructions in Monotype Composition Caster Manual (I will have to check this) because Casting Machine Adjustments only refers to the American-style trip lever. Position A of the cam now gives low-speed trip on single justification, and position N (I will have to check this too) gives low-speed trip on double justification. Since I am not using justification changes within the line I would probably not notice if the single justification that forms half of the line end is also tripping the lever due to the caster speed. I also tightened the locknut on the stop bolt, something which I neglected to do previously, as is clear in the first photo.

This left the job of replacing the post. I had good luck on two fronts there. I had a spare post which was easy to find because it was still in its place in the spare galley cam I have. I was also lucky in that the broken stub of the post was loose in its hole, so I could unscrew it by tapping on its just right using a small prick punch.

The replacement post 14F6

The repaired galley, with a bit of cleaning done as well.

So because I didn’t analyze the original problem properly, I ended up breaking another part. I was fortunate in that replacing it was fairly easy, and even if I did not have a spare on hand I could have made a suitable replacement.

Besides this, I had other problems casting as well, although I also had a couple of improvements from the previous casting session. Details to follow.