An Improved Means for Securing Stereotype Plates to their Base Blocks.
Year: 1888

page_text: Date of Application, 11th Aug., 1888
Specification Accepted, 14th Sept. 1888
An Improved Means for Securing Stereotype Plates to their
Base Blocks.
1, DAVID REID, of No. 112 Flinders Lane East, in the City of Melbourne, and
Colony of Victoria, Publisher, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascertained
in and by the following statement:
-
This invention relates to an improved means for securing stereotype plates to their
base blocks and it refers more particularly to that method of or means for securing
stereotype plates to their base blocks wherein a key is employed which in section
forms a double dovetail, the upper dovetail of which is fitted into a corresponding
groove on the under or back side of the stereotype plate; whilst the lower dovetail
is fitted into a correspondingly shaped groove on the upper face of the base block;
but I have found in practice that this arrangement for securing stereotype plates to
their base blocks is defective in some respects, inasmuch as it is incapable of
adjustment.
Now, according to my present invention, I still retain the double-dovetail key, but
I make it in two or more thicknesses, and the upper part of it in two or more
strips lengthwise, and I so connect the upper part of the key with its lower part
as to make it susceptible of adjustment, so as to provide for any possible inequality
in the face of the stereotype-block. By making it in strips lengthwise, I am enabled
to more accurately adjust any part of the face of the plate which requires adjust-
ment; and the best means I have found for effecting the vertical adjustment of the
upper plates of the key and consequently of the face of the stereotype plate,
means of two sets of screws, the one of which connects the upper plates to the
lower plates of the key, and the others of which form the supports for the upper
plates and constitute the means of adjusting it. This will be better understood on
reference to my drawings, in which,―
by
Figure 1 is a transverse vertical section of a stereotype-plate, adjustable double-
dovetail key, and base-block, constructed according to my invention.

page_text: Figure 2 is a plan of the adjustable double-dovetail key hereinbefore mentioned.
Figures 3 and 4 are respectively an elevation and a plan of one of the screws for
vertically adjusting the upper part of the key.
That part of the drawing which is indicated by the letter A, represents the base-
block formed with an undercut dovetail groove a to receive the lower dovetail 6 of the
key B, whilst the upper dovetail 6' of same fits into the undercut dovetail groove c in
the underside of the stereotype plate C.
D, D, represent ordinary screws holding the upper and the lower plates of the key
together, whilst E E represent the adjusting screws forined as shown with a shoulder e
to bear against the underside of the upper portion of the key B, whereby its thickness
may be readily adjusted by reason of the said screws raising the strips of which the
upper portion of the key B is constructed, as shown.
The operation of my invention is as follows, that is to say :-
Assuming that the printing comes up faint at any part, thereby indicating that the
stereotype plate is not perfectly flat, then it is only necessary, first, to slacken the
screws D at or about the faint part, then to unscrew the adjusting screws E at or
about the same part so as to raise their shoulders and thus raise that part of the
upper portion of the key so as to correct the inequality in the printing plate.
An alternative method of adjusting the face of the stereotype-plate is to dispense
with the adjusting screws E and to use thin metal liners or wedges between the
upper and lower plates of the key, but I prefer to use the screws E. Further, this
adjustment may be also effected even if the upper part of the key be made of one
plate instead of two or more but I prefer to make such upper part of the key in
three strips or widths, as shewn.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what
I claim is :-
1. In improved means for securing stereotype plates to their base blocks, an
adjustable double-dovetail key B, consisting of an upper and a lower part, suitably
connected together, substantially as herein described and explained.
2. The special means herein described of adjusting said double-dovetail key when
made of an upper and a lower part, such means consisting of adjusting screws E, in
combination with connecting screws D, as herein described and explained, reference
being had to the accompanying drawing.
3. Making the upper part of such double-dovetail key in two or more strips or
lengths so as to increase its adjustability.
Dated this Sixth day of July One thousand eight hundred and eighty-eight.