Friday, January 4, 2019 -- Matrix Size Matters
This is a story I have thought about writing for a while as I have not read any comments about the size and material of a matrix limiting its operating range.
Making Super Caster adaptors for different types of matrices is interesting in one way as we get to compare the capabilities of the various types of machines that ran them. One variable that may not readily come to mind is the ability of the matrix to withstand heat. For example, older foundry mats were in general quite large and could throw off a lot of heat. Think of the brass or copper body of an old foundry matrix as a radiator of a large car, the more surface area, the better it got rid of heat.
When the heat travels to the edges of a matrix, the gap, however small, is a significant boundary layer to limit the rapid conduction of heat away from the matrix. Reduce the heat conduction, and the matrix itself heats up. This was a critical factor as the old automatic casters were running foundry metal necessitating temperatures in the 700 to 800 degree F range, sometimes double-pumping the mould in an effort to fill the cavity before the type alloy froze, things were hot. By the way, when comparing the performance of a Monotype machine to an old foundry machine, I believe this is one of the major differences that limit Monotype machines (In my opinion, mould design to accommodate automatic jet cutting was the other major difference).
Heat was also a factor in the selection of a suitable matrix material. For example, we have a mould made by the Monotype Corporation that was designed to cast type from brass Ludlow matrices. At the time, the Super Caster pot at Pygment Press had some high-alloy stuff that ran at above 700 degrees. After testing a Ludlow decorative border matrix, it appeared to lose the shape of the image in the mat with sort of a ‘sandpaper’ look. I believe the zinc was being eroded out of the brass alloy, as the melting point of Zinc itself is only around 780 F. I also believe one reason English Monotype plated their brass display mats was to protect them from being broken down by heat but stay with a reasonably cost effective and a very malleable base metal.
The metal alloy for Monotype display mats was apparently 86-88% Copper, 10-12.5% Zinc and 0.9-1.3% Lead (the Lead content makes the metal easier to machine and potentially could also be drawn out by casting temperatures). Was English Monotype the first company to Chrome plate matrices? How was the process accomplished? I imagine the matrix is punched and then a thin flash of Nickel & Chrome is added for protection.
The same Zinc leaching effect would probably happen with Linotype matrices, however I'm not familiar with their exact metal composition. I went so far as to have a Linotype mat Chrome plated a few years ago to experiment with, however, this was not a path I further explored (yes, I worked on a Linotype holder for the Super Caster). I will leave casting individual pieces of type from Linotype matrices to the guys with Thompson type casters and the correct holders for this job.
Just a tangent comment, Chrome platers are an interesting bunch of people that work with bikers and custom car restorers and with lots of dangerous chemicals; they might not be exactly familiar with small casting matrices that fall to the bottom of a tank. But if I were to do it now, I would opt for a controlled thickness of Nickel plate and forget the Chrome. Note that as Chrome plating is typically clear, it is the underlining nickel that one sees. Controlling the thickness of plating is critical for controlling casting type-high tolerances, I would be tempted to tell the plating company “give me a thou (0.001”) of Nickel" and see what happens. Nickel plates to a brass or copper base object very well, it gets into every corner, I believe this is called 'throwing power'.
In his book "Practical Typecasting" Theo Rehak says ATF used a layer of Nickel in their production of electro mats, however, I believe this is a layer that becomes the face of the matrix because they are copying a pattern, different from the English Monotype procedure. This Nickel layer is then backed up by Copper. ATF apparently added 0.008" to 0.010" of Nickel, this would be one tough matrix, too bad Lanston Monotype never tried to do this with their electro matrices.
The only complaint I have ever had with English Monotype mats is that one time, the Chrome plating came off in one spot, revealing the Nickel below and ruining the matrix.
In the same argument, the small size of a bronze English Monotype matrix (94-95% Copper, 3-4% tin and 0.8-1.2% Lead) makes it vulnerable to heat; while the more expensive alloy should be more heat-resistant, the small size of the mat does not allow it to throw off the heat as well, so it probably operates at a higher temperature. I have found that casting bronze composition matrix sorts on the Super Caster with foundry metal is hard on the mats. I ran a batch of “@” signs in hard metal with the idea they would get a lot of impressions over the years of use, but I probably won’t do it again. Shown in the picture above is a large 72 pt. Giant Caster matrix, Nickel plated brass, and the smallest Monotype matrix, a 0.2” x 0.2” bronze composition matrix. I understand at one time, English Monotype offered chrome plated composition matrices as an option however I don't think this is very common.
Another discussion could be started concerning European matrices made out of steel, however I have not seen or used them.
This is a long ramble of thoughts that came up when looking at the possibilities and limitations of casting. I’m sure some of the ideas above have faults. As Oliver Wendell Holmes once wrote:
“If there are any anachronisms or other inaccuracies in this story, the reader will please to remember that the narrator’s memory is liable to be at fault, and if the event recorded interests him, will not worry over any little slips or stumbles”.
Friday, January 4, 2019 -- Matrix Size Matters
This is a story I have thought about writing for a while as I have not read any comments about the size and material of a matrix limiting its operating range.
Making Super Caster adaptors for different types of matrices is interesting in one way as we get to compare the capabilities of the various types of machines that ran them. One variable that may not readily come to mind is the ability of the matrix to withstand heat. For example, older foundry mats were in general quite large and could throw off a lot of heat. Think of the brass or copper body of an old foundry matrix as a radiator of a large car, the more surface area, the better it got rid of heat.
When the heat travels to the edges of a matrix, the gap, however small, is a significant boundary layer to limit the rapid conduction of heat away from the matrix. Reduce the heat conduction, and the matrix itself heats up. This was a critical factor as the old automatic casters were running foundry metal necessitating temperatures in the 700 to 800 degree F range, sometimes double-pumping the mould in an effort to fill the cavity before the type alloy froze, things were hot. By the way, when comparing the performance of a Monotype machine to an old foundry machine, I believe this is one of the major differences that limit Monotype machines (In my opinion, mould design to accommodate automatic jet cutting was the other major difference).
Heat was also a factor in the selection of a suitable matrix material. For example, we have a mould made by the Monotype Corporation that was designed to cast type from brass Ludlow matrices. At the time, the Super Caster pot at Pygment Press had some high-alloy stuff that ran at above 700 degrees. After testing a Ludlow decorative border matrix, it appeared to lose the shape of the image in the mat with sort of a ‘sandpaper’ look. I believe the zinc was being eroded out of the brass alloy, as the melting point of Zinc itself is only around 780 F. I also believe one reason English Monotype plated their brass display mats was to protect them from being broken down by heat but stay with a reasonably cost effective and a very malleable base metal.
The metal alloy for Monotype display mats was apparently 86-88% Copper, 10-12.5% Zinc and 0.9-1.3% Lead (the Lead content makes the metal easier to machine and potentially could also be drawn out by casting temperatures). Was English Monotype the first company to Chrome plate matrices? How was the process accomplished? I imagine the matrix is punched and then a thin flash of Nickel & Chrome is added for protection.
The same Zinc leaching effect would probably happen with Linotype matrices, however I'm not familiar with their exact metal composition. I went so far as to have a Linotype mat Chrome plated a few years ago to experiment with, however, this was not a path I further explored (yes, I worked on a Linotype holder for the Super Caster). I will leave casting individual pieces of type from Linotype matrices to the guys with Thompson type casters and the correct holders for this job.
Just a tangent comment, Chrome platers are an interesting bunch of people that work with bikers and custom car restorers and with lots of dangerous chemicals; they might not be exactly familiar with small casting matrices that fall to the bottom of a tank. But if I were to do it now, I would opt for a controlled thickness of Nickel plate and forget the Chrome. Note that as Chrome plating is typically clear, it is the underlining nickel that one sees. Controlling the thickness of plating is critical for controlling casting type-high tolerances, I would be tempted to tell the plating company “give me a thou (0.001”) of Nickel" and see what happens. Nickel plates to a brass or copper base object very well, it gets into every corner, I believe this is called 'throwing power'.
In his book "Practical Typecasting" Theo Rehak says ATF used a layer of Nickel in their production of electro mats, however, I believe this is a layer that becomes the face of the matrix because they are copying a pattern, different from the English Monotype procedure. This Nickel layer is then backed up by Copper. ATF apparently added 0.008" to 0.010" of Nickel, this would be one tough matrix, too bad Lanston Monotype never tried to do this with their electro matrices.
The only complaint I have ever had with English Monotype mats is that one time, the Chrome plating came off in one spot, revealing the Nickel below and ruining the matrix.
In the same argument, the small size of a bronze English Monotype matrix (94-95% Copper, 3-4% tin and 0.8-1.2% Lead) makes it vulnerable to heat; while the more expensive alloy should be more heat-resistant, the small size of the mat does not allow it to throw off the heat as well, so it probably operates at a higher temperature. I have found that casting bronze composition matrix sorts on the Super Caster with foundry metal is hard on the mats. I ran a batch of “@” signs in hard metal with the idea they would get a lot of impressions over the years of use, but I probably won’t do it again. Shown in the picture above is a large 72 pt. Giant Caster matrix, Nickel plated brass, and the smallest Monotype matrix, a 0.2” x 0.2” bronze composition matrix. I understand at one time, English Monotype offered chrome plated composition matrices as an option however I don't think this is very common.
Another discussion could be started concerning European matrices made out of steel, however I have not seen or used them.
This is a long ramble of thoughts that came up when looking at the possibilities and limitations of casting. I’m sure some of the ideas above have faults. As Oliver Wendell Holmes once wrote:
“If there are any anachronisms or other inaccuracies in this story, the reader will please to remember that the narrator’s memory is liable to be at fault, and if the event recorded interests him, will not worry over any little slips or stumbles”.