Engineering and Design Introduction

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Engineering and Design Introduction Mechanical
Tools and Equipment
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General Rules

• Tolerances- 1/16
• Yes, during training we will be (probably) be
  overly OCD about this- just so everything's
  correct for the actual season, when we don't have
  time to blow
• Angles
• Righty tighty, lefty loosey
• This refers to the top of the screw/bolt,
  assuming that you're looking down from the head
• i.e. clockwise tightens, counterclockwise loosens

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Drills

• Charging the power packs- always do it when one's
  run dry
• Two speed settings drilling (faster) and bolting
  (both of which we tend to call drilling...)
• Like, 15 torque settings
• Torquethe drill's ability to turn
• Tradeoff with speed (more on this later)
• Drilling should use the highest
• (conveniently labeled with the picture of a drill
  bit)
• Bolting should use 1-6, depending
• on the material
• Forwards/backwards

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Cutting drill bits

• Normal End is chamfered (slanted)
• at 118 degrees. Made of titanium.
• Wood End comes to a point in order to
• avoid splinters.
• Countersink Used to create a chamfer at the top
  of the hole

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Spade/Forstner Bits

• Spade/Paddle Bits Only for wood. They tend to
  leave splintering, but are also larger.
• Forstner Bits Only for wood, and the best.
  Creates a perfectly straight hole. Only used in
  the drill press.

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Dremel

• Hand-held drilling/cutting device
• Allows one to fairly rapidly sand out holes in
  metal and/or to polish stuff

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Hack Saw

• Cuts wood, metal

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Router

• Used to cut metal/wood
• It can be easily slid along the top of the thing,
  allowing you to cut awkward lines or thing that
  won't fit other tools

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Twisty Thingies

• Screwdrivers
• Several head types flat, phillips, etc

• Hex keys
• Aka Allen Wrenches

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Bolts vs. Screws

• Both bolts and screws are steel, threaded
  objects, with a head that prevents them from
  sliding further
• Bolts are designed to be able to go all the way
  through the material, and to be fastenable with a
  nut on the other side
• Screws aren't instead, they taper to a point
• We almost only use bolts, since we almost only
  use metal

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More on that last point

• When using bolts, you'll drill a hole (a pilot
  hole) through the metal, then just put the bolt
  through by hand, and put on the nut/washer
• But screws rely on being pushed into the actual
  material- and metal is either too thin or too
  tough for this to work

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Bolt classification

• They look like this ¼-20 x 6
• Means that it has a ¼ diameter, 20 threads/inch,
  and is 6 inches long
• Only really matters if you're on a purchasing
  trip or whatever
• Countersunk head instead of being flat, it fits
  neatly into a countersunk hole, making it
  stronger.

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Nuts

• Problem- how to stop the nut from just sliding
  back off?
• Several kinds
• Normal. It's a nut.
• ½ nut 2 of these would be placed on, so that the
  edges would face different angles and would be
  tougher to remove
• Keps nut. There's a circular, spinning metallic
  washer that, when pushed up against the surface,
  helps prevent it from sliding off

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Even more nuts

• (Ny)Lock nuts There's a thin coat of nylon
  between the threads bolts can still be put on,
  but the nylock, pushed between and outside the
  threads, makes any further movement difficult.
  They're nigh-impossible to put on by hand, and we
  generally only use them, since they're much
  better at resisting vibration
• Wing nuts Designed to be easy to slide on and
  off. Used in, e.g. our bumpers.

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Rivets

• tldr We hate them.
• The tool (rivet gun) on the left pushes air into
  the rivet (on the right), expanding the top until
  it has exceeded the original size of the hole and
  can't be pulled back, then the bottom pops off.

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Pros/Cons of Rivets

• They're cheap
• Their resistance to shifts parallel to the
  attached materials is as good as or better than
  bolts
• Completely immune to vibration (therefore used
  on airplanes, ships, etc- Rosie the Riveter)
• But They're not reusable, difficult to take out,
  and weaker perpendicular to the surface

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Measuring

• Rulers
• Straight rulers (yellow, metal w/ cardboard back)
• 90 degree angle thingies
• These should be obvious
• Same goes for the files/abrasive paper- in fact,
  I won't make a slide for them

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Files/Abrasive Paper

• Several kinds. For paper, the smaller the grit
  size, the finer the sandpaper is (slower but more
  accurate)
• For files, there's two kinds regular and
  dreadnought, which is faster and more destructive

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Threading tool

• Used to cut threads along the outside of a
  previously existing hole
• Super-important MAKE SURE the hole cut is the
  same size as you want it to be, and as the
  threading tool- otherwise you'll get it stuck, or
  it'll be unusable