Mechanical Sprocket

About This Project

Mechanical Sprocket

This project walks through the machining of a standard FS250-10 mechanical sprocket, which can be used in a variety of motor applications or adapted for other uses.


Post Date: July 20, 2016

Project Time: 2 Hours

Author: Sector 67

Difficulty:

This project walks through the machining of a standard FS250-10 mechanical sprocket, which can be used in a variety of motor applications or adapted for other uses.

Bill of Materials

  1.  1.5"x1."x1/2" aluminum plate - the plate can have a larger area, but must be at least 1.5" x 1.5"

Tools

  1. 0.25" Spot Drill
  2. 0.25" Jobber Drill
  3. 0.125" 2-Flute End Mill
  4. 0.375" 2-Flute End Mill

Step By Step

  1. The workholding for this piece can be done a variety of different ways, depending on the stock material you are using. You could do this part in two operations with a flip and precut soft jaws, but in this setup, we'll have the full depth of cut on one side. Start by clamping your stock in the vise with step jaws. Be sure that your steps aren't larger than 0.25" on each side, to provide clearance for the cutter.
  2. The first operation will clear off the top 0.100" of material.
  3. Next use the 0.25" spotting bit to create a divot for the drill to follow.
  4. Now, we drill our center hole. Doing this keeps maximum stock against the jaws, holding our stock securely.
  5. After drilling, we do more bulk removal. Do this with a bigger end mill (0.375") allows us to move the cutter faster and remove more material with each pass. Make sure that when you set up you account for the size of the bit when choosing your stock. Hitting the hardened jaws with a cutter is not going to end well.
  6. After the bulk removal, we can do our final profile with the 0.125" two-flute endmill. This will give us the final gear profile and release the part from the stock.