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Recyclers News Press
variants did not cut asquickly or last as long as the 14
TPI blades.
Testing demonstrates that a14TPI blade performed
best when cutting boron steel. A14TPI bladewas
usedduring the remaining tests in this report.
OptimumBladeSpeed (SPM) Setting:
Next, we
confirmed that speed at which the blade ran
(measured in strokes perminute, or SPM) had an im-
pact onboron steel cutting performance. A hand test
was conducted using anelectric powered reciprocat-
ing saw cutting theA-pillar of aMercedes-Benz using
a 14TPI bimetal blade. This testmeasuredhow long it
takes tomakeone complete cut in thematerial with a
failuremode of 2:00minutes. This test concludes that
in order toeffectivelymakea cut inboron steel, the
SPM setting of themachine is critical. Speed settings
of 1250-1500 show thebest results. If the speedof
the saw is set too high (>1500SPM) thenexcessive
heat is generated causing theblade to fail prema-
turely. For tests conducted in thisWhitePaper, the
speed setting of 1250-1500SPM is used.
ReciprocatingMachineandSpeedRange
Selection:
The target blade speed for which thema-
chinemustmaintain is 1250-1500SPM. Consistently
cuttingwithin this speed range is not possiblewithout
having an electronic speed control on the reciprocat-
ing saw. It is our recommendation that recyclers pur-
chasean inexpensiveoptical tachometer andmeas-
ure the blade speed of their reciprocatingmachine
whilemaking test cuts inanymetal. This will show:
If the sawhas enough lowend torque tooperateat
1250-1500SPM
If the sawhas a variable speed control circuit capable
of maintaining speedas feed force changes.
The speed control dial setting required on their spe-
cific recipmachine tomaintain 1250-1500SPM.
It’s different on everymachine.
Most importantly, personnel will experiencewhat
1250-1500SPM “feels” like. Having a senseof
this speed range is critical, and enables one to cut
at the correct speedwith any variable speed saw.
Orbital vs. Non-Orbital Setting:
Orbital cutting ac-
tion, found onmany reciprocatingmachines, was
originally developed to increase cutting speedwhen
cutting throughwood. Inmost caseswhen cutting
metal material, the aggressivemotion of orbital action
causes teeth to fractureand results in premature
blade failure. Results from our tests show that when
cutting boron steel with the proper SPMand in orbital
mode, blade performance increases. At these lower
blade speeds the teethdo not fracture prematurely;
thus it is our conclusion that when cutting boron steel,
the orbital setting aids inblade performance.
Summary:
In conclusion, a corded reciprocating saw
with speed control is thebest tool for cutting boron
steel pillars.
Based onmultiple tests, wemake the following blade
andmachineusage recommendations in order to suc-
cessfully cut boron steel:
BladeTPI &Specification: 14TPI is the best TPI for
this application. Our 1” Premiumbi-metal blades
(stock no.s 020-106-061, 020-106-072, and 020-
106-078) perform the best on this type ofmaterial
Speed of Blade: 1250- 1500SPM is the ideal blade
speed for optimum performance
Orbital vs. Non-Orbital setting: Orbital setting en-
hances theblade performance
CuttingUltraHighStrengthSteel
EffectivelyandSafely
Solutions toSolve theProblem for BoronSteel
