The Oskaloosa herald., 1915-10-21

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How does the efficiency Of the worn
drive axle compare with the beVsI driV'
axIef
Compared with single reduction
beVel gear the efficiency OF the worn
gear is undoubtedly lower. taking fol
granted the accuracy in manufacture
in both cases to be the same.
There is a steady tapping in my mo.
tor which cannot be located. II is nnore
| noticeable when there is a strain on the
motor. Can you explain It? .-
A bent valve stem will in nearly
every case cause a knock to be heard.
If fbe valve springs of any one cylin-
der are weak that cylinder may mis-
fire and give the effect of part slight
ly loose. See If the valve and ignition
timing are correct. Perhaps the noise
you hear is nothing more than a valve
slap. which is caused by the valve seat
Ing improperly.
The material of which the top Of my
battery is made has become cracked.
Can you tell me what to use to close
the cracks? "'r HiS nr..fe .sst
The best way to seal the cracks is to
play q torch on the compound SO as TO
melt it in the proximity of the breaks.
How can one find the firing order of
a motor?
A fairly good method is as follows:
Taking No. l cylinder. get both valves
so they are closed. Then turn the mo.
tOr. over slowly and watch for the next
cylinder to have both its valves closed
Tits will be the next cylinder TO fire.
Continue turning the motor crank
shaft, and note the next cylinder. with
its valves closed. and so on. Another
method is to open the petcocks. and
by holding the hand over them one ut
time the order OF the suction strokes
can be found and hence the firing or
derA
Van you HlN0 me A0fTb
easehardening stseI2
Casehardening of iron or steel refers
to a process of causing steel. after be-
ing sufficiently heated, to absorb GER
tain amount Of carbon, SO that the re-
sulting mass will have a coating or
case of a relatively hard substance.
The process of doing the work varies.
and a great variety of carbonaceouS
substances are used for introducing
the carbon into the metal. Solids are
used more extensively than either
liquids or gases for this work. and
some Of the more common substances
are charcoal obtained from wood or
bone; chaTred leather, mixture of
borium carbonate and charcoal in the
of 10 to 30 per cent respec-
lively, powdered bone, salt. 10 per cent;
charcoal, 80 per cent; animal black.
charcoal and potassium carbonate. po-
tassIum cyanide, etc.
The extent OF the haTdening-that is.
the thickness OF the case-will be de-
pendent upon three things-namely, the
Of the part TO be harden.
ed, the time the heated metal is in con-
tact with the carbonaceous material
and the kind OF material used for pro
during the case. The usual casehard-
ening temperature Is 1.65O degrees F.,
but the higher the temperature the
deeper will be the case. The article 10
be hardened is heated in a furnace and
when a cherry red is removed and en-
bedded in the hardening material
After removal 1t sometimes is custom
airy to heat treat the casehardened
steel. This is done by relocating to
about the same temperature or higher.
II possible, and then queDching in wa
ter or oil. A second heating often Is
given, but not as high as either OF the
others. .... .f RI. . a.. - .
my springs working loose and causing
a disasreeable rattle. ! do not wish to
renoVs the clips, but should like to
know no" to prevent their rafting. 70,
Perhaps the simplest way to prevent
loose clips Of this description from rat
ting is to wind the clip, especially the
part passing over the top leaf OF the
spring. with ordinary tire or electri-
clans tape. If this is neatly wound
and painted to match the spring It will
not look like bit OF patchwork and it
viii efrectually prevent the clip from
rafting or squeaking. .....r
Why does a motor n,isfirs with the
spark fully advanced at high speed?
The trouble probably is due to the
interrupter points being too far apart
on the break. However, while this
may cause the misfring, there may be