Re: Simple spur gear design
Hi, you can cut a gear with a fly cutter held in a boring bar in a vertical mill spindle, and cut the teeth on the side of the blank, using a dividing head to do the pitch indexing.
It's quicker to buy a dedicated gear tooth cutter on EBAY if you know the module or DP of the gear you want to cut.
If you have a 10X magnifier loupe or jewellers magnifier, you can hand grind the fly cutter profile using a similar gear as the pattern for the tooth form........I projected the form of the gear tooth at 100:1 magnification using a modified photographic enlarger and cut some gears like this years ago.
I drew the form of the gear on a piece of paper stuck to the wall at a distance of 10 feet and projected the image onto it, having first calibrated the ratio for the projection by projecting a 1/8" diam rod against an image that was 100 times that size or12.5 " wide.
Ian.
Re: Simple spur gear design
I remember years ago my young fella broke a bakalite spur gear in our valve refacing machine and we were in a huge hurry to get it up and running so I got a old tap that had the same pitch as the gear and ground 3 of the flutes off and used it in our bridgeport turret mill to cut the teeth on a alluminium blank we machined,that machine is still running perfect at least 6 years later.I guess if its not a accurate part theres lots of ways to fix. it
Re: Simple spur gear design
Look at gearotic.com. A really neat gear drawing and machining programm