Improvements in the Manufacture of Cast Iron or Steel Cutting Tools.
Year: 1899

page_text: Date of Application, 21st Oct., 1899
Complete Specification Left. 16th Aug., 1900-Accepted, 16th Oct., 1900
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Cast Iron or Steel Cutting Tools.
I, HEINRICH ECKARDT, Civil Engineer, residing at Bach-Strasse 12A, in the
City of Berlin, Kingdom of Prussia, and part of the German Empire, do hereby
declare the nature of this invention to be as follows:-
This invention has reference to a process for manufacturing cast iron or steel
tools by means of which these tools can be manufactured at a comparately low
temperature in a common crucible furnace, the invention making it possible to
put an edge to the tools several times without the necessity of a repeated temper-
ing process. Though the material used for the manufacture of these tools con-
tains but a low percentage of steel not more than 50 per cent, the tools obtained
therewith present all the good qualities of those made from ordinary tool steel.
The invention consists in the employment of a certain amount of fero-man-
ganese and of aluminium along with steel and iron scraps and of ingot iron.
As an instance of carrying out my invention I will describe a mixture and the
use of the same which I have found serviceable for most purposes, by way of
example:
The basis of the material for casting the tools, is a cast iron with about 2
to per cent. carbon its composition on being fused in the crucible, is approxi-
mately as follows:-
50 pounds good hematite crude iror
46
"
7
"
1,4
0,014
"
old ordinary tool steel scraps
good specular iron with about 12 % of manganese.
ferro manganese with about 60 to 80 % of manganese
aluminium.
If the reverbaratory furnace is used the composition has to be changed accord-
ingly because in the reverberatory furnace there is a combustion of carbon taking
place which necessitates a higher percentage of carbon to be used from the start.
The material does not need the high temperature required for the fusion of
crucible steel, but can be fused in the ordinary crucible furnace used for melting
metals generally. The casting is effected in seperate moulds without tempering
of any of the components or parts. The edge is put on the tool by heating the
whole tool or only the part nearest the edge to red heat and then tempering in
water, the same as for tool-steel.
A new edge can be ground on one to three times without the necessity of re-
peated tempering or by tempering the tool over again, an edge may be put on
any number of times until the tool is consumed.
The scraps of the used up tools may be used as an admixture for the casting of
new tools.
These tools may be employed for any purpose and if duly taken care of, the
edge will be found more durable than in using tool steel.
The process forming the subject of my invention, is distinguished from casts

page_text: made with chill casting and from the tools forged from tool steel, be the following
features: --
1/. The fools are not forged and though not malleable, they are harder and
more susceptible to the treatment with fire and acids than steel.
2. The tools may be cast and an edge put on without a chilled cast working
edge, while tools from chilled steel have to be discarded after the first edge being
worn off.
Berlin, Germany, this 16th day of Üctober 1899.
WALTER FOLKMAR,
Agent for Applicant.
Improvements in the Manufacture of Cast Iron or Steel Cutting Tools.
I, HEINRICH ECKARDT, Civil Engineer, residing at 12A, Bach-Strasse, in the
City of Berlin, Kingdom of Prussia and German Empire, 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 has reference to a process for manufacturing cast iron or steel
tools by means of which these tools can be manufactured at a comparately low
temperature in a common crucible furnace, the invention making it possible to
put an edge to the tools several times without the necessity of a repeated temper-
ing process. Though the material used for the manufacture of these tools con-
tains but a low percentage of steel not more than 50% per cent. the tools obtained
therewith present all the good qualities of those made from ordinary tool steel.
The invention consists in the employment of a certain amount of ferro manganese
and of aluminium along with the steel and iron scraps and of ingot iron.
As an instance for carrying out my invention, I will describe a mixture and the
use of the same which I have found serviceable for most purposes, by way of
example.
The basis of the material for casting the tools is a cast iron with about 2
to 2 per cent. carbon; its composition on being fused in the crucible is approxi-
mately as follows:-
50 pounds good hematite crude iron,
46
7
1,4
0,014
"
"
""
"
old ordinary tool steel scraps,
good specular iron with about 12 % of
manganese,
ferro manganese with about 60 to 80 per cent, manganese,
aluminium.
If the reverberatory furnace is used, the composition has to be changed accord-
ingly because in the reverberatory furnace there is a combustion of carbon taking
place which necessitates a higher percentage of carbon to be used from the start.
The material does not need the high temperature required for the fusion of
crucible steel, but can be fused in the ordinary crucible furnace used for melting
metals generally. The casting is effected in separate moulds without tempering
of any of the components or parts. The edge is put on the tool by heating the
whole tool or only the part nearest the edge to red heat and then tempering in
water, the same as for tool steel.
A new edge can be ground on one to three times without the necessity of re-
peated tempering or by tempering the tool over again, an edge may be put on
any number of times until the tool is consumed.

page_text: The scraps of the used up tools may be used as an admixture for the casting of
new tools.
These tools may be employed for any purpose and if duly taken care of, the
edge will be found more durable than in any tool made with tool steel.
The process forming the subject of this invention, is distinguished from casts
made with chill casting and from the tools forged from tool steel, by the following
features:-
1/. The tools are not forged and though not malleable, they are harder and
more susceptible to the treatment with fire and acids than steel.
2/. The tools may be cast and an edge put on without a chilled cast working
edge, while tools from chilled steel have to be discarded after the first edge has
worn off.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare what I
claim is:-
The process for the manufacture of cast iron or steel cutting tools which con-
sists in using as a raw material for casting these tools, an iron with but a low
percentage of steel, preferably tool steel scraps and containing a certain amount.
of ferro manganese and of aluminium, heating such mixture to a temperature
below that employed with ordinary tool steel and casting the tools without pre-
liminary tempering of any of the parts, whereby a tool is obtained to which an
edge may be put any number of times without the necessity of repeated temper-
ing, substantially as and for the purpose set forth.
Dated this 31st day of July 1900.
WALTER FOLKMAR,
Agent for Applicant.