Making a Spring Powered Motor - Page 2

Copyright 2008 by James P. Riser

The first step in getting ready is to gather up some required materials.

I already have a good assortment of spring steel for the motor. These coils are left overs from previous jobs and my R&D supply:

I have brass sheet in many thicknesses plus brass bar stock up to 4" in diameter. I can saw discs from the bars to get any desired gear thickness. With my circle shear I can cut gears any size from up to .080" thick. And with my big punch I can easily punch out gear blanks up to 1/8" thick. I am in good shape for raw materials.

Here are a couple sizes of punched brass gear blanks.

I have a very few Thornton wheel cutters; but need more and several pinion cutters of appropriate sizes. So .. I shall make my own as the "real cutters" are too expensive for me. Being able to make my own tooling is very handy. The commercial cutters start at $90 each! Below are shown clock cutters on the left. This is the size of cutters that I will be making. On the right are shown the clock cutters with watch cutters for a size comparison.

The cutters that I will be making are 4 toothed cutters.

I decided to make my wheel and pinion cutters from 1" diameter A-2 air hardening tool steel.

Here is an assortment of A-2 drill rod that I will be using for this project.

The cutters that I will be making are cut from 1" diameter A-2.

The steel discs were cut on my bandsaw.


This left burs on the edge.


The wheels were cleaned up quickly on my belt grinder.

The next step was to convert these discs into wheels having parallel sides and a properly sized arbor hole to fit my machines.

A pot chuck was machined to hold the discs for shaping.


The first side was smoothed up.


A center drill was used to start the arbor hole.


Several twist drills were used to work up to the required hole diameter.


The Edge of the hole was beveled with the center drill.


The disc was removed from the chuck, turned over and the back side cleaned up and beveled.


The finished disc looked like this.

Before working on the rest of the wheel and pinion cutter blanks, I thought it a good idea to check the fit on my pinion mill.

Perfect fit and it runs true!

I'll continue with things after I have machined all 21 of the cutter blanks.

Well, all 21 discs are arbor hole drilled and ready for the next step.

Before I can continue with this project, I need to machine the special holder for turning the required relieved teeth. The metal for this is cut and I have picked up the required 7mm - 1 tap for the arbor hole mounting bolt, as well as, the needed dowel pin.

This 1" diameter by 3" long A-2 rod will become the cutter holder for machining the cutters.

More as I find time.