On 10/20/2014 3:47 PM, andy pugh wrote: > In the end, I deicded to do it like this: > http://youtu.be/86MN3CN7Aiw
Very likely how it was originally done, large diameter cutters to minimize dishing of the ramps. Could use a specially made four position indexer with power feed and rotate timed to advance and turn it just right. Or if the manufacturer didn't make enough to warrant building special equipment, rotate the dividing head 90 degrees for each step. More laborious and potential for errors with the dividing head, but cost of special fixture VS time cost of labor would be the deciding factor. What I'd like to see is a film of the machines used to cut those hourglass shaped worm gears in steering gear boxes when there was no CNC or even punched paper tape controlled machine tools. I've seen some old equipment controlled by cams and levers and timing gears etc, but someone had to either hand cut all those precisely, or hand cut the parts that controlled a machine to machine cut the cams etc for production machines. CNC has wiped out everything between the draftsman and the finished product, and people can still goof things up. ;) Somewhere I read a forum post by a person who worked for a company that made high pressure fittings. They sent one off to a company building a deep sea submersible, then realized they'd gotten the bolt pattern backwards. They called the company to inform them of the error and were relieved to hear that the person doing the install had drilled through from the wrong side of the bulkhead, so the backwards fitting fit perfectly. :) Just change the plans and, what error? Was always that way... --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com ------------------------------------------------------------------------------ Comprehensive Server Monitoring with Site24x7. Monitor 10 servers for $9/Month. Get alerted through email, SMS, voice calls or mobile push notifications. Take corrective actions from your mobile device. http://p.sf.net/sfu/Zoho _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
