Re: [CAD_CAM_EDM_DRO] Re: Cool Worm Gear

Smoke wrote:

> Let me see if I've got this right:
>
> You set up a tap in the lathe between centers....presumably fixed so it
> won't rotate.
> no the tap must rotate
> Then you mount the blank on the lathe saddle...presumably in an index
> fixture or in a rotary table for indexing and it hast to be on an angle to
> suit the lead of the screw thread.

you mount the gear on a fixture perpendicular to the tap the gear must be
able to be fairly rigid but able to rotate freely
just if you have a mill mount the tap in the chuck and mount the gear betwen
rotary table and tailstock remember that the wheel must turn freely,start the tap
around 250 rpm offer the tap to the gear and you will see , ive got the
formulas to calculate the diameter of the worm wheel in function of the
pitch of the tap but ive got no time to post them today
regards
mariano

> The blank would be on edge with it's
> bore parallel to the floor but on an angle relative to the centerline
> between the spindle and tailstock.
>
> The tooth cutting would then be made by runnint the table back and forth in
> the "Y" dirrection? If I draw a sketch of what I just wrote, I can see how
> this would work for a gear who' pitch radius equalled the distance from the
> center of the rotary table to the pitch line of the tap...but the cuts would
> be awfully heavy. But how would you cut gears of other diameters?
>
> Wouldn't it be easier to mount a 60 degree vee cutter in the mill spindle,
> mount the blank in the index table at the proper angle and simple run the
> cutter thru the blank using the Y feed on the table?
>
> Smoke
>
> >
> >I did it by mounting the blank on an arbor in a spin indexer, which
> >was mounted in my mill vice. The indexer was tilted to get the correct
> >angle on the blank and then cut with a slitting saw. Fortunately, the
> >number of teeth I needed could be done with an indexer, otherwise you
> >might have to use a dividing head.
> >
>
> Welcome to CAD_CAM_EDM_DRO@...,an unmoderated list for the discussion of shop built systems, for CAD, CAM, EDM, and DRO.
>
> Addresses:
> Post message: CAD_CAM_EDM_DRO@egroups.com
> Subscribe: CAD_CAM_EDM_DRO-subscribe@egroups.com
> Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@egroups.com
> List owner: CAD_CAM_EDM_DRO-owner@egroups.com, wanliker@...
> Moderator: jmelson@... [Moderator]
> URL to this page: http://www.egroups.com/group/CAD_CAM_EDM_DRO
> FAQ: http://www.ktmarketing.com/faq.html
> bill,
> List Manager