Formulas Flashcards
What is the formula to calculate imperial tap drill size?
TDS = MD - (1/N)
Where:
* TDS is the tap drill size,
* MD is the major diameter and
* N is the number of threads per inch.
How do you calculate the outside diameter of a machine screw?
OD = (Screw # x 0.013) + 0.060
How do you calculate the tap drill size (TDS) of a machine screw?
TDS = OD - (1/Screw #)
Screw number is threads per inch.
How do you calculate metric tap drill size?
TDS = MD - Pitch
Calculating torque wrench values when an extension is used.
(A/B) = (T/t)
Where:
A = torque wrench length with extension
B = original torque wrench length
T = torque with extension
t = original torque
How is the torque setting calculated when a torque multiplier is used?
Multiplier ratio x friction loss = new ratio
Required torque / new ratio = torque wrench setting with multiplier
The multiplier ratio is adjusted for friction loss and then the required torque setting is divided by this new adjusted ratio.
How do you calculate blade length when making a new blade for a band saw?
Blade length = pi x (diameter of one pulley/2) x center distance
What is the formula for calculating imperial spindle speed for a drill or mill?
rpm = (CS x 4)/Dia
Where:
Dia = the diameter of the drill or cutter.
What is the formula for calculating metric spindle speed for a drill or mill?
rpm = (CS x 320)/Dia
Where:
Dia = the diameter of the drill or cutter.
What is the formula for calculating mill cutter feed rate?
Feed = Chip load x Spindle speed x # of teeth
What is the metric formula for spindle speed on a lathe?
rpm = (CS x 320)/Dia
Where
* rpm is revolutions per minute.
* CS is cutting speed in meters per minute.
* Dia is diameter of the workpiece in millimeters.
What is the imperial formula for spindle speed on a lathe?
rpm = (CS x 4)/Dia
Where
* rpm is revolutions per minute.
* CS is cutting speed in surface feet per minute (SFPM).
* D is diameter of the workpiece in inches.
If using straight depth to calculate the final depth of cut when cutting treads, what is the formula to calculate straight depth of cut?
Straight depth of cut = 0.6134 x pitch
How do you calculate the imperial amount of tailstock offset for a desired taper?
TSO = (TPF x OL)/24
Where
TSO = tailstock offset
TPF = taper per foot
OL = Overall length
How do you calculate the metric amount of tailstock offset for a desired taper?
TSO = [(Dia - dia)/(2 x TL)] x OL
Where
TSO = tailstock offset
Dia = Large diameter
dia = Small diameter
TL = Taper length
OL =Overall length
What is the formula for calculating the safe working load of a single vertical rope?
SWL = (# of 3/8” sections x 1 ton) + (# of 1/8” sections x 1 ton)
What is the formula for calculating the safe working load of a basket hitch?
SWL = SWL1 x (H/L) x 2
Where:
SWL1 = safe working load for a vertical rope of a certain diameter
H = distance between hook and load
L = length of sling legs
What is the formula for calculating the safe working load of a two-leg bridle hitch?
SWL = SWL1 x (H/L) x 2
Where:
SWL1 = safe working load for a vertical rope of a certain diameter
H = distance between hook and load
L = length of sling legs
What is the formula for calculating the safe working load of a choker hitch with an angle over 45-degrees?
SWL = SWL1 x 3/4
Where:
SWL1 = safe working load for a vertical rope of a certain diameter
What is the formula for calculating the safe working load of a choker hitch with an angle of 45-degrees or less?
SWL = SWL1 x (A/B)
Where:
SWL1 = safe working load for a vertical rope of a certain diameter
A = distance between hook and load
B = length of sling legs
What is the formula for calculating the safe working load of a pair of choker hitches?
SWL = SWL1 x (A/B) x (H/L) x 2
Where:
SWL1 = safe working load for a vertical rope of a certain diameter
A = distance between hook and load at the choker hitch
B = length of sling legs at the choker hitch
H = distance from main hook
L = length of sling from main hook to choker hitch
What is the formula for calculating the safe working load of a double basket hitch?
SWL = SWL1 x (H/L) x 4
Where:
SWL1 = safe working load for a vertical rope of a certain diameter
H = distance from the hook to the load
L = length of the sling
In a bridle hitch what formula is used to determine the sling tension?
Sling tension = (W/N) x (L/V)
Where:
W is the weight of the load.
N is the number of slings. This value can never be more than two.
L is the length of the slings.
V is the vertical height from the load to the sling’s attachment point.
What is the formula for calculating change in length of metal due to temperature change?
ΔL = Lo × ΔT × α
Where:
ΔL = Change in length
Lo = Original length
ΔT = Change in temperature
α = Coefficient of linear expansion
What is the formula to determine shim size when levelling a machine with a precision level?
X = G x (A/B)
Where:
X = Shim height at machine surface
G = Feeler gauge or shim height at precision level
A = length of surface to be levelled
B = Length of precision level
