Iowa County democrat. [volume] (Mineral Point, Wis.) 1877-1938, 1888-12-14
HOW SAWS ARE MADE.
Cutting the Teeth, Tempering, Grinding, Pol
ishing, Rounding, and Truing,

| Cutting the Teeth, Tempering. Grinding. Pol
/ ishing, Rounding, and Truing,
Ordinary circular saws are of all sizes
| from six inches to six feet IN diameter,
| says Pittsburs Dispatch writer. The
| plates from which shey are made come
| from the steel mills IN circular form, al
most round, if not perfectly So. The
! first thing to be done IS to see that each
| plate is made perfect circle. hole is
! then cut IN the center and the teeth are
| marked sround the rim. The plate is
! then taken 20 big machine on which he
! teeth are to be cut. Il is placed upon a
| plu at such \ distance from the machine
| that the edge comes beneath the die Gnd
| the operation Of tseth-cutting begins.
1t requires powerful machine TO do this
work, as TIE steel is cut cold, each tooth
being made from oae blow from the heavy
iron jaw. All sizes and descriptions OF
dies are necessary, as the styles of saws
aud saw teeth are many.
After the teeth have been cut-snd the
work Is quickly done-the next operation
Is that of temperIpg, which IS not only
the most particular but also the most i'm
portaat job in the n aking OF saw. The
temperlpg furnace Is q sort of oven,
heatsd By nstarsl gas. Several saws are
placed in the furnace st time and al
lowed 20 remain until the eye os the eS-
perieIcsd workman tells him they have
teached the proper teul erature. This he
knows by the color of the
glowing metsl-when il becomes
light cherry red the plates
must be taken from the oven and plunged
into e vat of whale oil. A few words
about this vat and how it is repared for
its work. When the cover is removed
! the RECEPTACLE Is seen 10 be nearly full of
thick, dark-coloFed OIL liquid, which must
b7 warmed TO O certain degree before the
saws are put IN. The vat is got ready
while the plates are heating. The manner
of warming the visclG. ciammy oil is
peculiar. Pieces of red hot iron or steel
axe placed N the vat, one after another,
uutii its contents are properly melted.
As each Eisce IS dropped in brilliant
fame leaps from t. { surface of OF! ard
continues to burn until extipguish ed by
! : ing the liquid with q long iron rod.
! Wan al is in readiness and the large,
glowing plates cautiously sid INTO the vat
| the fleet is beautiful. Tie flames leap
! aigt than ever, aud The oil RACES aud
| seoshcs ike witches cauldron. Leave
| ing the temperiDg department. the saw
| goes back 10 the main shop to be ham
mered and stTaig hteued ready for grind
! iIg. This work Is done with hammer
| and anvil and requires much care, skill,
! ard precision. After the plate, which
| had been more or iFss wrapped Curing tbs
| TEN peripg process, has been made per
| fectly straighJ again 1t IS placed in tie
| grinding machine to remove all super
| tiuous metal and TedGce the saw to the re
| CURED thinuess. Here the saw Is made
! fast on Il carriage between two wheels,
| which turn 1t and at the same time press
its sides against a rapidly revolving grind
| stone. The carriage is fixed IN automatic
| bearings, aud is moved back and forth
| at the VIII OF the operator. 1t usually
! takes about two hours to grind tyefoot
! circular saH, though the time varies ac
| cording to the kind of saw that is being
! made.
The next operation is that OF polishing
! which is done with emery wheels. To
! polish a largo circular saw the plato Is
| secured 10 large wheel or flange. which
! turns, carry ing the saw with it, the work
| man meanwhile pressing an emery ball
! attached 20 handie) against the side.
! The saw must then be round ed that is,
/ care must be takeu to prevent one tooth
! prof Getting further than the others. For
! this pur pose the saw is placed in bear
/ ing and made TO tGru slowly. 1t Is then
/ grad lal!y brought III contact With an
!. emery wheel, the latter turning very
swiftly, until the edge OF every tooth
| touches the wheel. Ghe saw is next
| sharpeEei and submitted TO further ham
meriug fer the purpose Of "traing" and
straig hteu1n2, and is then cesed ready for
| shipment,
One irn portant part of the saw-maker's
business is the renovation of old saws.
| As every body knows, sawniils belong to
that descripti' Of buildings which are
most Frequently destroyed b. fire. After
the mill F,ss been reduced to ashss the
| saw is usually found somewhere among
the ruins, warped and soOrohed ont of all
rembrance to Its former self. But al
though the mill is complete ruin the
saw is not, in spite OF its damaged appear.
anCe, and back IT goes to the manu- ct
G-er 70 be Strengthened up, tempered over
again, and provided with a new set of
teeth. What might be styled the dental
| department of the saw-wOrks renders as
good service 10 the proprietcrs Of saw
NUT machinery as regular dentists do the
owners of defective teeth. A saw wears
down rapidly with use, and the time i'll
evitably comes when it must return to the
shop and get new teeth, else its usefulness
for cutting logs will be gone forever.
| This happens again and again, until tbs
saw is completely worn ont, or at least
reduced to dimensions that make 1T no
| LONGER seryiCeabie,