fastening and attaching

In contrast to our first project, a 1D bottle-opener that was made from a single piece of Delrin, our next project requires a bit more than just one piece of plastic. Thus, we learned various methods of fastening and attaching in order to put one or more pieces together to create an assembly. The following is a quick pro/cons/features reflection of the four methods that we practiced in class.

heat staking.

Heat-staking is a process that connects two pieces of an assembly together by heating pieces until material fuses together. Somewhat similar to the notch & peg method of attaching, heat staking is comprised of two pieces of an assembly with one piece having a "peg" bit that goes into another piece. It is the "head" of the peg that is then heated to fuse the pieces together. 

pros:

• If done correctly, the result is unmovable and durable.
• Ideal for joints that are not meant to move. 
• Allows for a slight degree of imprecision; is forgiving as long as pieces fit together.

cons:

• Time consuming. Can take up to one minute per joint.
• joint is completely unmovable.

piano wire.

To use piano wire to join two or more pieces together, one must drill a hole through all of the pieces to thread the piano wire through.

pros:

• adjustable strength. can be hinge-y or completely unnmovable.
• easy to do, doesn't necessarily require too much planning in SolidWorks compared to notches/heat staking/bushing

cons: 

• very time consuming
• joints could possibly loosen (?)

notches + pegs
 This seems self explanatory...
pros:

• adjustable strength for the bond. can loosely fit, tightly fit, anywhere in between

cons

• very easy to get wrong in SolidWorks/ due to variability of any particular piece of material.

bushings

rings of delrin around delrin rod to help hold a rod in place.
pros

• adjustable strength. like notch/peg, can loosely fit, tightly fit, anywhere in between

cons

• also like notches + pegs, it is very easy to get wrong due to inaccurate measurements/variability of material, etc.