Matrix repair or new.

[Dan Williams]

Economics briefly aside, I think this is a legitimate academic question that is begging for answers. Sorry I dont have the info. But it seems that more than a few people are possibly interested (Craig, Mike, and yes me) and John Henry probably has the best insight to the process. Here is what I suggest, and I am totally honest. Someone should be encouraged to research this as part of their high school or college project. They would get expert advise (under a professor or advisor) would get access to information and people that others would not, and would have the available time. They could publish or post what they find, get bread-and-butter transcript credit and everyone could benefit. A patent search could be a start, and then interviews with folks like John Henry. You know, Mergenthaler was making mats into the 70s. Bet there are hundreds of people who made mats now enjoying retirement or 2nd careers. They wouldnt know or necessarily care that anyone is asking these questions. But if some kids call with questions.... Boy, I hope someone takes up the challenge.

[craig_star]

I am going to buy some flat cz120 engraving brass bar from smithsmetals. They sell it at 3/4" wide, the same as matrices and various thicknesses.  I'll use their bespoke cutting service to lop it into rectangles. Then I will cut the key (pi) with a £150 new custom cutter. Then I will measure a 'a' 18pt mat and mill the new brass to these measurements.
My friends wife works in a jewelry shop which just bought a new £20000 engraving machine. I'm going to have a play with it.    

[mikefrommontana]

Keep us appraised to the results, as this sounds very interesting.   Of especial curiosity will be if the face can be kept to a uniform depth.  I know Ludlow resorted to engraved mats at the end of production and some folks have complained of them not having a uniform depth of drive.   I suspect this is why punched mats were preferred, but the engraving likely will remove some post punching finishing. 

I am also curious if the metallurgical makeup of the matrices will influence the engraving.  It seems a lot of the newer mats seem to be of a very yellow (high zinc content) brass, which I suspect may not be the preferred metal for engraving.   If you know somebody with a Thompson caster, it would be a good way to test the durability of the mats--though what to do with the intervening thousands of sorts might be a question.

Keep us posted.  I'm going to toss this question out on the LETPRESS List and the Intertypeworld lists and see if there are any other folks with interest or knowledge applicable.

Michael Seitz
Missoula MT 

[Dave Hughes]

Just to reiterate what Mike said, Craig, it does sound like a very interesting project, which is of interest to many people here on Metal Type.

Please keep us informed on your progress. If you need any help posting photographs on the message board, you could email them to me metaltype-AT-gmail.com and I would be happy to host them and illustrate your posts.

Or you could take a look at the sharing services provided by www.photobox.com or others.

[mikefrommontana]

A couple notes on mat suppliers:

Woodside Press appears to be a trade typesetting house only--they're not selling mats off.  At least that's how I read it.

Linecasting Machinery sells English depth of drive mats (.050 instead of U.S. .030 if I recall).  Unless a machine is set up for those mats, either the slugs come out over height or they won't cast at all.   English and U.S. mats cannot be mixed together.

G.T. Graphic Service and Supply  http://www.gthotmetal.net/FontList.htm also sells mats along with SOS Linotype in the US, along with such collections we all might luck into.

Just because our machinery is fussy and precise is no reason it can't run for a long long time.  It's up to us, that's all.

Michael Seitz
Missoula MT

[jhenry]

I have sent Dave Hughes some pictures of some of the equipment used to produce mats by engraving. It may take him a while to get them posted ot the site, so when I do see them, I will try to describe the process and further describe the machines involved as best I can remember them.

I would be excited to hear from others who have engraved or stamped mats, and particularly from anyone who is hoping to develop the skills involved.

I've added John's pics to his post, they have a brief description on the pic, but I'll let John explain more fully - Admin




This was used to reduce the thickness of the matrix ears (lino) in order to run correctly thorugh the magazine. The mats were stacked in the magazine and pushed indivudually through under the cutters by moving the lever on the left.



This was the broach used to create the proper key combination on linecaster mats. The levers were raised or lowered in various combinations for the particular characters being cut at the time. The mats were put in the carriers and then pushed through the broach to cut the combinations.



These machiens were utilized in finishing the side faces of the mat in order to smooth them and to create this correct side-bearings.



This little milling machine was capable of being changed from a vertical mill to a horizontal mill and was used to take the brass bar stock and form it into the proper format for the lino or ludlow mat bodies.



The optical comparitor was used to check for proper alignment, either using a sample from the run of mats it had to match, or using the ralative position from the edge and top of the mat body. It was also used for evaluating the cutting tool, which had to be sharpend "just so" in order to get the proper shoulder and face.



This is the pantograph engraver used for mat engraving at Kayenay. I believe most of the mats were engraved at a 50:1 reduction, meaning that the pattern plate was 50 times larger than the mat charcter being engraved. The pattern plates were photopolymer plates, and the can of car wax sitting on the machine was used to lightly lubricate the pattern plate so it didn't grab the stylus while tracing. It was important to use circular motions opposed to the spin of the cutter in order to get the cleanest floor on the engraving, which later became the actual face of the characters being cast. Of course, the last passes as you increased the depth were the most critical in that regard.



This a shaper which was used to cut border slides of rule faces. It was also used to cut the Identification and size lines on Ludlow mats where required.



This is a closer look at one of the side finishing mills. These clamped the mat on the sliding table and the side face was passed across the face of the spinning milling head They were capable of shaving off just a whisker-width to give a good finish to the side and to give the mat the proper side-berings.

[Dave Hughes]

Robin Kenworthy contacted me via email to add the following:

They need to read Typographical Printing Surfaces, Legros and Grant 1916, pages 193 to 240 cover punch cutting and mats.

A quick check at Open Book lists several libraries that hold a copy and the last on ebay made $211, as  I said before my copy will fall apart if I open flat to scan.