Metal Exam Part 1 Flashcards
What units is cutting speed usually given in?
surface feet per minute (sfpm) or meters per minute (mpm)
What is the formula for spindle RPM?
RPM = CSx4/D
What is the speed of a rotating machine measured in?
Revolutions per minute (RPM)
Where is the fastest moving surface on a rotating part?
The outer circumference
What diameter is used in RPM calculations when TRUNING on a lathe?
stock diameter
What diameter is used in RPM calculations when DRILLING on a lathe?
drill diameter
What should your lathe speed be for rough cuts?
0.015”/rev (0.38mm/rev)
What should your lathe speed be for finishing cuts?
0.007”/rev (0.13mm/rev)
In gas welding how can the weld pool be cooled?
adding more filler
material or moving the torch away
In arc welding how can the weld pool be cooled?
change the angle of the rod or
turn down the power
What is the tank startup procedure for gas welding?
- A before O
- Regulators backed out
- No leaks
- Acetylene ¼ turn
-Oxygen all the way open - Always use a striker
-Take great care with the torch
Away from people
Away from the tanks and hoses
What should your pressures be for gas welding?
- Acetylene never exceeds 7 or 8 psi (max is 15 psi, Unstable at 28 psi)
- Oxygen can go up to 40 psi for cutting
Pewter is made up of what alloys?
Tin, Copper, Antimony
What are the dangerous of old pewter?
Can contain lead
(Lead free is available)
Can cuttle bone molds be reused?
Yes