Jeppesen Sheet Metal Flashcards
Name 5 methods of forming sheet metal
- Bending 2. Folding 3. Bumping 4. Stretching 5. Shrinking
What happens to the stem of a friction lock (self-plugging) rivet when the rivet is installed?
The stem is pulled until it snaps off
The difference between Cherry Max and Cherry Lock
Cherry Lock rivets require separate tool for installation of each size Cherry Max requires only one
The process for determining the total length of a solid rivet for an installation
Add the thickness of the materials being joined together + 1.5x Rivet diameter
The minimum edge distance and spacing that should be used for a single row of protruding head rivets
not less than 2 rivet diameters for edge distance Not less than 3 rivet diameters apart from each other
How the mechanic will determine whether the countersink for a flush rivet should be dimpled or drilled
Thickness of the top sheet Thin sheets are dimpled Thick sheets are countersunk
The action taken to prevent cracks from forming while dimpling magnesium or other hard sheet metals
Hot dimpling (heat the metal) before dimpling
The type of damage that can occur when the rivet set is not correct for the type of rivet
Radius too small- Rivet head will be damaged Radius too big- Sheet metal will be damaged
The importance of the proper size and weighted bucking bar for rivet installation
Too large- difficult to control Too small- Rivet will not be properly upset before work hardening
Proper procedure for properly removing a rivet
- Center punch the rivet 2. Drill to the base of the head 3. Use pin punch to take off head and knock out tail
The 2 special calculation required in order to bend sheet metal
- Setback 2. Bend allowance
The 2 factors in determining the amount of set back
- Bend radius 2. Material thickness
What is done to a corner where two bends intersect to prevent cracking
Relief hole drilled into corner
2 reasons for drilling lighting holes into sheet metal wing rib
- Reduce weight 2. Increase stiffness
The purpose for a joggle
Offset at the intersection of two or more sheets of metal, allows them to be stacked flat together
The name of the what this technican is layingout/ cutting out
Lightning holes
The name for the hole at the corner/ intersection of the bend
Relief hole
