Calculators


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Lapidary Diamond Blade Technical Information

Lapidary Blade Speed Recommendations - Scroll down for Surface Feet Calculator

	MK-297 Criterion	MK-301 Gemking	MK-1000 Saber	MK-303 Pro
	Recommended RPM Operating Range in Surface Feet Per Minute (SFPM)
	3000 - 3500 SFPM	4500 - 6000 SFPM	4500 - 6000 SFPM	3000 - 4500 SFPM
Blade Diameter	Approximate Arbor Shaft RPM Range
4" (102mm)	2860 - 3340	2860 - 4300	4300 - 5730	4300 - 5730
5" (127mm)	2290 - 2670	2290 - 3440	3440 - 4580	3440 - 4580
6" (152mm)	1910 - 2230	1910 - 2870	2870 - 3820	2870 - 3820
7" (178mm)	1640 - 1910	1640 - 2460	2460 - 3270	2460 - 3270
8" (203mm)	1430 - 1670	1430 - 2150	2150 - 2870	2150 - 2870
9" (229mm)	1270 - 1490	1270 - 1910	1910 - 2550	1910 - 2550
10" (254mm)	1150 - 1340	1150 - 1720	1720 - 2290	1720 - 2290
12" (305mm)	960 - 1110	960 - 1430	1430 - 1910	1430 - 1910
14" (356mm)	820 - 960	820 - 1230	1230 - 1640	1230 - 1640
16" (406mm)	720 - 840	720 - 1070	1070 - 1430	1070 - 1430
18" (457mm)	640 - 740	640 - 960	960 - 1270	960 - 1270
20" (508mm)	570 - 670	570 - 860	860 - 1150	860 - 1150
24" (610mm)	480 - 560	480 - 720	720 - 960	720 - 960
30" (762mm)	380 - 450	380 - 570	570 - 760	570 - 760
36" (914mm)	320 - 370	320 - 480	480 - 640	480 - 640

Calculators

1) Click Reset
2) Enter all but one value
3) Click Compute

Calculate Surface Feet Per Minute
SFM = (Pi * Dia * RPM) / 12
SFM = Surface Feet Per Minute
Dia = Diameter (inches)
RPM = Revs Per Minute

Convert Between Inches & Millimeters
.03936" = 1mm 25.4mm = 1"

Convert From Fraction to Decimal
(Does not go from decimal to fraction)

Calculator Java scripts courtesy of
The Machinists' Exchange On-line.
© The Machinists' Exchange On-line.
Used with permission.