Lesson 5: Cone

Lesson 5: Cone

• Draw out your cone on paper in side view.
• Make sure that your drawing is to scale.
• Using a compass, place the point at the tip of the cone, and adjust the legs so that the pencil tip hits each corner.
• Draw ¾ of a circle with the compass.
• Measure and set your compass to the distance between the 2 bottom points.
• Place your compass point on the left point and make a tic mark with the pencil.
• Repeat with the right point.
• Bring your compass in to 1/6 of the previous length.
• Mark this distance onto the end of one of your tic marks.
• This will give you 3.14 (pi- π) the diameter of your cone!
• Draw straight lines from the center point out to the end tic marks.
• This is your pattern for your cone.
• Make sure that you have made notes on each measurement.
• If you like, cut out the paper template and bend and tape to make sure it is the right shape that you are looking for.
• When you are happy with your paper version, repeat the layout process on metal, using dividers instead of the compass.
• Cut out your template and file the edges smooth.
• Using your half round needle file, file down the thickness at the tip of the cone.
• Anneal.
• Mark lines from the center out to the bottom with your scribe.
• Place in the vise and bend.
• Bend around so that the edges meet.
• Hammer on shoulders to bring edge in close together.
• Solder and pickle.
• Hammer on the cone stake to round out the form.
• Planish.
• Check against the steel square to make sure the sides of the cone are straight and not flared.
• File the bottom edge flat. Use the steel square to make sure you are filing evenly.
• Solder to a bottom plate.
• Cut off any excess and file.
• File and sand the cone to 600.

Tips and tricks:

• The thinner to tip of your cone is, the easier it will bend around.
• To make sure that your cone is indeed round, trace around the bottom on a sheet of paper. Rotate the form slightly and make sure that it still lines up with the drawing.
• If drilling an airhole, do that in the bottom plate before soldering.
• For an open top cone, mark where you want the cone to end on your profile drawing. Draw a ¾ around those marks as well as the bottom marks. If you are doing an open top cone, there is no need to file down the thickness at the top edge.

Homework:

Using 20ga. brass, create a closed cone. The cone should be 1.5-2” high with a 1-2” diameter. The cone should be finished, filed and sanded to 600 grit. There should be no visible airhole.

Due beginning of class October 10.