Gear Cutting

As I started to fish my newly made reel this spring, I found that the original ratchet and pawl were wearing quickly, as evidenced by brass particles inside the reel back plate. I posted this problem to Rod and Reel Maker’s Forum. New design and new materials are needed.

So this morning I have cut gear teeth for the first time. Here is the new blank of 642 bronze (harder than the original brass) being cut by a 36 DP gear cutter, on my Sherline mill.

gear cutting

You can see that the column supporting the gear blank is tall and slender. This caused a high noise level during cutting. I will make a new one of 1 inch stock; the original shown here is 0.5 inch.

I bought the gear cutter from a supply house that was having a clearance sale. Made the arbor from 1 inch stock. If I had this to do again, I would use 642 bronze instead of 360 brass. The arbor has a 3/4-16 internal thread (to fit the mill headstock) and it was difficult to single point the thread with Sherline’s delicate tool. 642 bronze will cut much more smoothly.

Below, CW from top: new gear cutter, original 60 degree V-groove cutter, original 36 tooth brass ratchet, gear puller to take ratchet off reel shaft, new 30 tooth gear/ratchet.

ratchet tools

The new gear cutter is much more rigid than the V-groove cutter, which rang at a high pitch.

Next step is to make new fixtures for the new, longer pawl (material yet undecided).

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This entry was posted in Milling, Ratchet/Gear and tagged , . Bookmark the permalink.

5 Responses to Gear Cutting

  1. Great looking setup Dave! Very nice work on the tooling. Cutting gears is always a noisy proposition on these small machines!

    cheers,
    Michael

  2. Pingback: Results of Pawl Wear Test | North Branch Reels

  3. richard westerfrield says:

    how did you fit the abor in the rotery table? . my rotery table is 2mt so its tayperd
    is your rotery table tayperd ? you say to use 642 bronze in makeing the aboer.
    thank you
    richard westerfield

    • dave49 says:

      Richard,
      My rotary table is made by Sherline, and it has a 7/16 pilot diameter, with a 3/8-16 UNC thread below. No taper.
      I made the arbor for the gear cutter from 360 brass. It fits the 3/4-16 UNF thread on the nose of my headstock. Because of the way 360 crumbles when machined, I found it difficult to cut this thread. The internal threading tool is springy and wanted to dig in. Had I used 642 bronze, I think there would have been a smooth, continuous chip. I use 642 for rachet wheels, and so have it on hand.
      Dave

  4. richard westerfrield says:

    thanks for the information
    richard westerfield

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