The PDF versions of our catalogue and New Products List have been updated to fix a couple of mistakes, to update the pricing for 1st cut cotton linters, and to add our new #16 needles.
Price increase for 1st cut cotton linters pulp
We recently purchased a new lot of 1st cut cotton linters pulp and have found that the wholesale price has risen substantially since we last restocked.
As a result, effective immediately, we are raising our price for this pulp to $9.25 per kilogram ($4.20 per pound), representing an increase of about 15% over our old price. That may sound like a big jump, but one has to keep in mind that up until now we have held the same price for around 15 years, and there has certainly been more than 15% inflation over this period.
We expect that our 2nd cut cotton linters pulp will suffer a similar price increase next time we order some.
Monotype Pneumatics: Paper Tower air supply
Just for a lark, I tried connecting my Monotype caster to a compressed air supply, and found that the air connection to the paper tower leaked so badly that the (admittedly small) compressor could not keep up. I tried putting a little grease on the connection but that did not help much.
The air supply rises from below the caster table to the top of the paper tower in the tube to the left of the photo and enters into the connector, which is installed over the pivot shaft for the paper clamp. It is held on by a nut and washer which clamp it against a spacer collar. The shaft is hollow with a radial hole (facing away from the camera) to allow the air to pass from the connector through the shaft to the paper clamp. The nut can’t be tight against the connector because the shaft must pivot a bit as the paper clamp moves up and down for each cycle of the caster. I have to wonder what prevents the nut from working itself loose from this movement. I think the nut actually tightens against the end of the shaft (not the connector) and so the nut ans washer are locked to the shaft and rotate with it.
I suspect that the leakage is due to a subtle bend in the riser pipe skewing the connector a bit. Flexing the pipe causes the leakage to change dramatically.
I took the joint apart and found that the spacing collar does not appear (to me, anyway) to be long enough, causing the connector to tighten against the shoulder of the shaft instead. The lengthwise position of the shaft is determined by a groove that the pinch screw of the paper clamp (upper right in the photos) passes through so I can’t just move the shaft in a tiny bit.
I will be doing some careful measuring to try to determine what surfaces should be providing the air seal here. It may, for instance, be that the inside of the connector should be a closer fit to the shaft to provide a seal. It might be possible to find a pair of O-rings to fit the recess in either end of the connector, or perhaps a pair of thin flat resilient washers will do the trick.
This recess on either side of the connector might be able to hold an O-ring.
In any case, despite the leakage, I managed to apply some air to the system. I found that many of the airpins were stuck, and even when unstuck some still failed to rise. Several years ago, when I first started work on the caster, I had used an inflating needle to inject air directly into each hole in the table where the paper tower mounts, and the pins worked well then. This makes me wonder if the pipes in the paper tower are plugged with dust. The interior of the tower certainly had plenty of oily dust in it!
Monotype Pneumatics: Two Steps Forward (again)
After breaking two pipe ends while reinstalling the mounting plate for the Unit Adding valve, I decided that soldering in new ends would be easier than trying to get a flaring tool into the tight spots under the Monotype caster’s table.
I used my lathe again to thread some spare pipe ends to fit the mounting hardware, and bent and cut them to match the broken pieces I had cut out from the caster. I tinned the ends that were to be soldered to make the solder job a bit easier. I also cut two short pieces of ¼″ soft copper tubing to make connectors. These were a looser fit that I would have liked, but still close enough for a solder joint to work. In retrospect I probably could have used by lathe to swage the tubing to the correct inside diameter.
I cleaned and fluxed the pipes to be soldered, installed the new pipe ends into the valve mounting plate, and slipped my makeshift couplings into position. I soldered the couplings using a small butane torch and finished reinstalling the valve mounting plate and the dummy valve.
You can see the finished solder joints and below and to the right of each the flare couplings that I used to splice in the original pipe repairs I had done.
The Unit Adding dummy valve reinstalled on its mounting plate
There are still two valves left to do: the Quadding & Centering valve and the pneumatic mould signalling valve. I hope I can get them done with no further broken pipe ends!
The OCADU Book Arts Fair
On Saturday November 30th 2013, from 10am to 5pm, OCAD University will be holding its 29th annual Book Arts Fair, and the Papertrail will have a table or two selling our supplies and paper products.
This fair is held annually in the Great Hall of OCAD University at 100 McCaul Street in Toronto. Dozens of artists, printmakers, bookbinders, and other book artists will be there showing and selling their work.
We will bring with us bookbinding and marbling supplies, how-to books, our handmade paper and marbled paper. If you want anything else we sell, or a large quantity of what we might be bringing, you can order from us in advance for pickup at the fair and avoid shipping charges.
Monotype Pneumatics: Two steps forward, two steps back!
I put my replacement pneumatic lines on my Monotype caster and replaced the Unit Adding valve mounting plate. You can see them in the photo as the two clean pipes near the bottom, and the two shiny threaded ends second row from the top. My measurements worked out well, with the pipe ends coming out at the right locations with no force required.
To assist in fitting each pipe end through the appropriate hole in the plate I put short pieces of spring wire in each pipe and passed these wires through the matching holes in the plate. I attached the plate to the edge of the table using its mounting screws, then pushed each pipe individually to the exact spot so it would pop into its hole (the spring wire only held them in approximate position).
Unfortunately in doing this the threaded ends broke off two other pipes, so I am back to where I was with two pipes to repair and fit to this mounting plate.
Because I can’t reliably form flared pipe ends (and have no clearance here for the flaring tool anyway) I will have to use soldered connections to put replacement threaded ends on the broken pipes. I am reasonably sure that a short length of ¼″ copper tubing will work as a solder splice for this pipe.
I will have to be more careful reinstalling the other two mounting plates (for the Quadding & Centering valve and the pneumatic mould signalling). Although better that the soft iron wire I used when installing the Unit Shift valve mounting plate, the spring wire still doesn’t really do the positioning trick well. A better solution would be short tubes whose outside diameter matched the smaller diameter of the tee nuts and which were threaded to screw onto the pipe ends. Such tubes would position each tube exactly and would eliminate the need to push or pry the tube ends into position.
Replacement safety curtain guides for platen press
Stephen Sword, a friend from the Book Arts Guild of Richmond Hill, has a platen press at home fitted with a safety curtain. A metal frame rises above the edge of the platen as the press closes to push the operator’s hand away from the platen to avoid hand injuries. The frame is also fitted with a cloth curtain so the operator can’t put their hand through the frame when it is up (which would cause injury as the frame drops after impression).
The frame slides in two guides on either upper corner of the back of the platen, but being sliding parts they are subject to wear. On this particular press both guides have worn out and the right-hand guide has been replaced by a bent strap of sheet metal which looks rather makeshift and out of place on this old press.
Stephen also helps various museums and letterpress operators keep old presses in good condition and has noticed similar worn guides on other presses.
Three replacement guides with the original worn-out one below them, and three strips waiting to be bent, all sitting on the drawing.
He asked if I could make some replacement guides that looked more contemporary and less home-made. I’ve been sitting on the task for months but this week I finally started working on them. All I really had as a model was the broken piece of one of the original guides, so I had to guess somewhat at the dimensions. From the shape of the old part it looks to me like the same guide was to be used with frames made of either round rod or ¾×⅛″ flat stock.
I clamped a guide to my metal-cutting bandsaw so I could reliably cut strips ½″ wide from 16 gauge steel sheet. I smoothed off the edges with a file, and cut each strip in three lengthwise. Using a hammer, a vise, and a short piece of ⅜″ rod I formed the strips to match the actual-size printout of the drawing I had made. As it turned out I had not cut the first strip exactly in 3 so two of the guides are a bit short and the third had to be trimmed. The second strap was cut more evenly and I should be able to get 3 complete guides from it.
All that is left is to drill the mounting holes, and give the parts an old look by heating them with the torch to blacken them, and rubbing some oil into the surface to prevent rust. And then hope they fit properly.
Tagged with: Stephen Sword
Western Marbling workshop
We will be holding a workshop in introductory western marbling on Saturday, November 9th, from 9am to 4pm (with a 1-hour lunch break) at our store in New Dundee.
This hands-on course provides an overview of the materials and methods used for western-style (“Turkish”) marbling, with the students doing practical work using acrylic paints on methyl cellulose size.
The fee for this course is $65.00 plus 13% HST for a total of $73.45 per person, including all materials.
If you wish to participate, you should reserve your place as soon as possible. For details, or to book a place in this workshop, please contact us.
Monotype Pneumatics: Tubing repair
A previous owner of my Monotype composition caster had done a bit of a butcher job repairing a broken tube under the table. There were two soldered joints (using fittings not designed for solder joints) and two tees with capped side branches acting as straight couplers, and the resulting repaired tube no longer actually went to the proper location, the mounting plate for the Unit Adding control valve. Granted, the caster is not equipped with this attachment and the splice does the job, but I felt that I should replace it with the proper piping.
This is what is behind the mounting plate for the Unit Adding valve:
As is typical, removing the mounting plate has allowed the pipes to spring out of position. The spliced tubes should actually lead to two positions between the first and second rows from the top, and the dummy valve joins their airways.
I found two flare unions of the correct size in my spare parts, along with some pieces of pipe that were more or less straight and already had one end flared. I had tested my flaring tool on a sample of the pipe. I found that after a fashion I could get a flared end, but in the process the outside of the tubing became badly scarred from slipping in the clamp of the flaring tool, so it was good to find tubing already flared.
The joints to the mounting plate itself are unlike any other joint I have ever seen: The soft copper tubing is threaded and a regular nut and a special tee nut are threaded on, tightening against each other with the mounting plate clamped between them. The tee nut fits into a counterbore on the mounting plate so the front surface of the plate is flat, allowing it to join to the valve.
In order to loosen or tighten the tee nuts, a special screwdriver is required that can fit into the counterbore and also over the possibly projecting end of the copper tubing but still engage in the drive slots of the tee nut. I made the screwdriver by carefully grinding down a regular screwdriver.
The tubing has an outside diameter of 0.165″ and an inside diameter of a little over 0.086″. Its threaded ends are a non-standard size, #8-40, but rather than buying a special threading die (and waiting for it to arrive) I used my lathe to thread the two tubing ends. For this to be possible I had to do it before bending the tubing so the tube would fit through the bore of the lathe spindle. This in turn meant that I had to measure the shape of the bent tubing and calculate the correct length of straight tubing required, including accounting for the fact that the ¾″ bend radius required less tubing length than the measured sharp bend layout.
Threading the tubing on the lathe was simple to do; rather than cutting the depth to a particular dimension I cut until the nut test-fitted properly.
After marking out the bends and using a 1½″ pipe as a bending arbor, I had my finished pipes:
I will be able to do the final adjustment of the shape of the pipes when I install them. The mounting plate and dummy valve have been cleaned already, so now I can install my pipe repairs and reinstall the plate and valve.
Monotype Pneumatics: Quadding and Centering actuators
The Quadding and Centering system on the Monotype composition caster is controlled by two actuators on the paper tower.
The one for Quadding is a simple piston inside the tower housing which causes the motion of the paper tower cam to rotate a notched counting wheel; only when the counting wheel has advanced 5 (or 10) positions (to the next notch) is the paper ribbon allowed to advance. As a result the character coded on the ribbon is repeated 5 (or 10) times. The choice of 5 or 10 is controlled by rotating part of the notched counter wheel, thus closing up half its notches.
The one for Centering is a rocker arm outside the tower housing which is tilted one way to initiate centering by preventing paper ribbon advance, and is tilted back to its normal position when a sensor on the galley detects that the line is full. It is also forced to its normal position when both Quadding and Centering are coded on the same ribbon line (which IMHO is a keyboarding error).
Both of these receive their pneumatic signals via a manifold in the mounting plate of the Unit Shift valve, and these control signals originate in another valve (to be detailed later) mounted on the rear apron of the caster table.
The Centering actuator contains quite a few parts with a bit of clever pneumatics involved:
The clever part is the reset piston (which returns the rocker arm to its normal position). Firstly, it is a double piston, so it can either be actuated by the line-full signal from the galley or by the redundant selection of both Quadding and Centering on the same ribbon position. Each of these signals has its own isolated cavity in the cylinder, and either one will raise the upper piston and push the rocker arm to its normal position. Secondly, by using a larger diameter piston for the reset piston, the air pressure that rocks the arm when starting centering is able to be overcome by the reset piston actuated by the same pressure.
It should be noted that the two mounting screws (the long ones above and below the pistons) are not the same length (and are shown in the wrong positions in the above photo). The longer screw penetrates into the inside of the paper tower housing and acts as a mounting screw for the Quadding actuator as well.
The centering actuator was reassembled and installed on the side of the paper tower facing the operator just below the notched Quadding counting wheel:
The second photo is taken looking obliquely downward between the paper tower and the centering pin arm from the left side of the machine.
The Quadding actuator is installed inside the paper tower and all the air lines connect to the manifold in the Unit Shift Valve mounting plate:
The Centering actuator is also visible in the first photo.
The next pneumatic parts to clean are the dummy valve and mounting plate for Unit Adding, and I might also correct the messy repair job on one of the related air lines.