Fabricating multi tooth cycloidal cutters for clocks. Part 1

[@robdon6458]

A fantastic series of videos on cutter making. A possible tip regarding O1 tool steel. It is usually pretty good regarding work hardening but will do so if the tool is rubbing rather than cutting. Try increasing the rake on the form tool. Thanks for making the time to give us your experience.

[@NakedMachinist]

Great series so far. I've always wanted to build a clock and now that I'm married, my first one will go to her.

[@darynradcliffe2909]

Looking forward to part two !

[@mpetersen6]

First,do the entire Jo in one set-up. When you have the stock in the collet take a light cut off the od. Then drill the center hold undersized. Then bore he hole o straighten it out. The drilled holes can be offset a little. The reamer I'll follow the hole. This why you bore the hole. Using a parting tool undercut the back side of the cutter blank. Now go and do your forming work for your tooth profile. Now part the blank off. Doing he form cuts while mounted on a 5/16th or 8mm arbor is just looking for problems. When using the Eureka Relieving Tool normally you have the gullets already cut on the blank. There are a few videos on the web of them being used.

[@mpetersen6]

If you have access to somebody with a Wire EDM then you could have cutters cut to the form you want. Off course form tools really require a lot of support along with support of the part in the chuck or collet. Plus lots of cutting fluid. Rigidity is the name of the game. As to holding a short ice in the saw just put another piece of stock the same size on the other end of the vise.

[@craynerd]

Hi, nice video. I’ve had a eureka tool (see my videos) but it was so complex that unless built perfectly (beyond my ability), the eureka tool itself entered too much error into the cutter!

[@bornagainclocks650]

Hey Craynerd, I had debated about the eureka tool also. I had decided it was way too much fartin around....The design here will have some relief from the leading edge with a radial rake when setting up to cut the cutter teeth. Thanks for the response and have fun.

[@6NBERLS]

I've read that O-1 steel does not change dimension when it is hardened. My understanding is that other tool steels will change dimension and have to be ground after hardening to get them within tolerance.

[@bornagainclocks650]

Hey 6NBERLS, thank for the comment, different steels will have different responses to different manufacturing processes. there are so many today it can make your head spin (at least mine) trying to figure out what would be best for your project. I think it would be safe to say that if you have real tight tolerances to go by then you would heat treat and grind to specs most any type of steel, including O-1. Have a great day.

[@mpetersen6]

In terms of dimensional stability A-2 or A-6 are way better than any O series or W series steel. It's because they undergo less stress because they are air quenching. The stabilest O series I have used is O-6. Commercial trade name Graph-Mo. If all you are cutting is brass then I think it would work all right. I have used O-1 and L-6 for form cutters and countersinks. They worked well enough. L-6 is another oil hardening tool steel used for both fixture and die work.

[@pauldevey8628]

You mentioned making your own clock. Do you have a design? I am looking for a simple time only clock design. Paul

[@PaulLoatman]

Are you related to Bob Porter by chance?