Improvements in the Method of and Apparatus for Dressing Stone.
Year: 1891

page_text: Date of Application, 9th May, 1891-Accepted, 13th June, 1891
COMPLETE SPECIFICATION.
Improvements in the Method of and Apparatus for Dressing Stone.
I ALBERT DITTMER, Science Teacher, of 21 Wilsnackerstrausse Berlin, in the
Empire of Germany, 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 for improvements in the method of and apparatus for dressing
stone consists in the manner or method of cutting or paring the stone and in the
arrangement of the tool for cutting or paring. The tool is secured at right angles
to the stock and is employed in such a manner that the stones to be dressed to a
cornice or column or the like are pared or cut by removing an annular portion of
the stone leaving a centre portion of the required form and an outer portion which
is broken away by blows of a hammer or otherwise as the dressing progresses.
The cutting tool is secured with its cutting edge corresponding to the finished
contour of the stone to be dressed at the part of the stone to be cut away and
parallel to the axis of the stone. The tool cuts a groove leaving the outer surface
of the stone projecting so that it can be readily broken away to the end of the
groove.
After the cutting tool is once properly set, the stone can be dressed quickly and
easily from the rough with considerably less power than can be done with any
known methods by supporting and rotating it in a lathe and gradually moving the
rest to which the stock of the tool is fixed along parallel to the axis of the work,
a groove being first cut and then the outer portion broken off so as to leave the
work properly shaped without necessitating measurement during the process as has
been heretofore necessary.
By employing this method and apparatus by which the stone is cut in a longi-
tudinal direction instead of at right angles to this direction as in the previously
known methods, very long and slender and very short stone can be dressed without
risk of cracking or breaking. In addition the cutting tool is considerably less worn
however hard the stone then are the tools previously known.
In the accompanying sheet of illustrative drawings.
Fig. 1 is a side elevation of the cutting apparatus.
Fig. 2 is a front end elevation.
Fig. 3 is a back end elevation, and
Fig. 4 is a section through A-B Fig. 1 & 2 of the same.
Fig. 5 shows the manner of applying the apparatus to the dressing of a column
from the rough stone.
The cutting apparatus consists of a stock a provided with the guide b, the
passage c and the tube d, and of the cutting tool e with the guiding groove f and
the passage g. The cutting tool e is firmly secured to the stock a by the screws h
and preferably perpendicularly to it so that different cutting-tools as desired may
be employed with one stock. The real cutting surface k of the cutting-tool e is
according to the material to be worked, of steel and serrated, or as in the present
case provided with diamonds and is always shaped according to the object to be
worked out.
The passages c in the stock a and in the cutting tool e serve as a conduit for
the necessary water during the dressing, or also, if the material to be dressed is
soft, such as limestone, for a supply of emery powder. Over the tube piece d is
drawn a rubber pipe, which communicates with a vessel filled with water, or with a
funnel filled with emery powder.

page_text: Fig. 5 shows the manner in which this cutting apparatus is employed which is as
follows:-
The rough stone is prepared in the ordinary way for the required object and
fixed in a lathe, the cutting apparatus is fastened by its stock a to a sliding saddle
or support in such a way, that the cutting tool e can be forced into the stone as it
is turned, (Fig. 5). The cutting tool is forced into the stone up to its stock a.
The groove thus produced permits the piece 7 projecting freely from the body of
the stone to be broken away by a blow or by an iron crow, so that in this way a
perfect paring of the required object is produced, in this case a column, as shown in
Fig. 5.
to the
During the forcing in of the cutting tool e sufficient water is continually supplied
through d, c and g to the cut groove in order to cool the tool e, or in the case of
soft stone only emery powder is supplied in the same way through d, c and
cutting surface, the feed being maintained by means of the shaking or jar produced
by the working.
When the object to be dressed is inclined or curved, then the saddle or support
is guided in the well-known manner by a pattern or guide corresponding to the
incline or curve, so that the cutting apparatus when once properly adjusted can
follow пр the cutting without further adjustment even if the side to be dressed does
not form a straight line.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is :-
1. The method of dressing stones consisting is cutting out a groove by means of
a cutting tool forced into the stone along the contour of the object to be dressed to
produce the groove and then breaking away the outer portion in pieces substantially
as described.
2. An apparatus for dressing stone consisting of the cutting tool e secured to the
stock a and provided with the guide f and cutting surface substantially as
described.
3. In combination with the cutting apparatus claimed in Claim 2, the water or
emery feeding arrangement deg passing through the stock a and cutting tool e
substantially as described.
Dated this 9th day of May 1891.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.