Eureka form relief tool

Post by stephen thomas » Thu Mar 27, am. Privacy Terms. The Home Machinist! A site dedicated to enthusiasts of all skill levels and disciplines of the metalworking hobby. Skip to content.

Quick links. Eureka gear cutter relieving tool Post by shapeaholic » Wed Mar 26, am Some time ago I ran across a site that had a short video clip of an Eureka form relieving tool in motion. I am interested in making one and would appreciate it if some one could send me the site address.

Thanks Pete. At the moment I am having some ISP problems, my home page and email is down so I'm hoping this gets out. I still have the. May I get back to you later when my ISP problems are resolved? John S. OK John? Peter B UK. Sorry, Just sold a full sized one about 4 weeks ago. Comment Post Cancel. In the absence of a Eureka, you might consider producing a four flute cutter using the offset center method to get back relief on the contours. John Stevenson had a writeup about that two or three years ago and I think others have also illustrated it.

J Tiers. The traditional method for watch and clock people is the one shown in the Goodrich book. You make the cutter with a circular profile, Section it into teeth and toothspaces, then slit under the teeth and bend them inward to form the relief.

There is at least one solid model of the Eureka on GrabCad. The drawings in Law's book have been reduced to where they are difficult to read. Bob Fisher. Originally posted by jameslea View Post. Originally posted by Bob Fisher View Post. What the hell is. A Eureka? It seems to have something to do with clocks but I'mmissing it. George Seal. More recently John Stevenson wrote up a procedure on one of the discussion groups about using a tapered endmill to produce the cutter.

The tapered endmill has a range of radii so you can position it for the size you need, plus it's producing the required clearance automatically.

If you get way enthusiastic about gear cutters, the Ivan Law book has a chapter at the back about building a device to actually make circular form-relieved cutters. Lots of good options.

Robert Campbell Jr. View Profile View Forum Posts. Good question, I'll be watching for the answer too. Obviously with the CAD profile, a template could be accurately made, which would work with a tracer lathe, so maybe you are close enough with your tool room lathe?

My choice in design might be a pantograph style, with a say, ratio, to "magnify" accuracy, though it runs the risk of multiple points of "working clearance" in which to multiply error.

Though much harder to accurately grind the template profile, a ratio could provide great accuracy if executed and employed well. A set could be produced for a range of radii, to suit larger and smaller gears.

The beauty of this system would be the ability to lock the compound gib, thereby providing an absolutely ridgid duplication of the template. IE, a rock solid link between guide pin and tool, with the compound clearance closed.

Making the assumption that the template mount could become needlessly complex to provide very ridgid, lateral adjustment for, I think that I'd use a mandrel to hold the to-size blank between threaded collars, mount between centers and then locate the collars to center the blank on the template, using a lock nut against one of the collars, so that it's opposite would be the one that was removed, thereby holding-place for additional blanks.

Just cuz" I couldn't find a way to hastily delete my post in embarrassment EDIT, and there ya' go, Goldberg made me fergit' the complex profile relief, which of course John Stevenson brilliantly didn't My one stab at duplicated profile turning, which had a pleasing outcome, wasn't for a cutting tool Thanks for the suggestions.

I don't know how they can say that the lowest number of teeth for a given gear number size cutter would be the theoretically correct profile????? It may be close, but the profile they are making is a full radius not an involute.

I did have one interesting find. I haven't read it yest, but at first glance I don't know how it is done either. I mean I can imagine how the relieving attachment on the lathe bobs in and out to make the cutter I've done that much with a shop made contraption but the actual full formed profile of the relieving tool I made from comparison to a sample gear.

So that was cheating And even at that, the cutting action of a full profile cutter chomping away on a relieving lathe is not exactly 'nice and smooth'. There's got to be some kind of mechanical linkage that would allow one to profile cut the involute cutter with a simple fixed radius lathe tool. It's quite a complex process and requires you to make special tooling.

The big issue is cutting the relief on each tooth. Originally Posted by TGTool. I may get crucified for saying this but I have cut lots of gears using hss lathe bits in fly cutter heads I used the old gear as a template for grinding the tool. Take it slow and use your dividing head and you can get decent results. Originally Posted by kpotter. JB C and L Machine liked this post. I have access to Mastercam with gear tooth software.

I would machine the male contour on a cnc mill of the space between the teeth of the correct profile of the gear that I wanted to cut with a fly-cutter tool.