Author Topic: Eureka form relief tool  (Read 46867 times)

Offline philf

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Re: Eureka form relief tool
« Reply #50 on: January 11, 2023, 04:26:06 PM »
Hi Boo,

I have a Eureka (like Andrew I didn't make it).

Mine looks to be the same as the one published in Ivan Law's "Gears and Gear Cutting" but was made for 19mm (or maybe 3/4") bore cutters and I modified it to take 16mm. I don't think you need to scale everything.

I'm not keen on machining gauge plate - it's certainly a lot more difficult than mild steel. There are only a few bits listed that require hardening and the book suggests case hardened mild steel. Hardening and tempering gauge plate is (to me anyway) easier than case hardening.

As an aside we used to use KE672 steel for making tools at work. KE672 and Gauge Plate were of similar ingredients but our toolroom 'much' preferred KE672 for its machining properties.

The pawl on mine is easily fileable so definitely not case hardened.

Phil.
« Last Edit: January 14, 2023, 05:15:10 AM by philf »
Phil Fern
Location: Marple, Cheshire

Offline philf

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Re: Eureka form relief tool
« Reply #51 on: January 13, 2023, 03:49:16 PM »
I was thinking of building a Eureka tool to assist in making gear cutters for small gears for model engines but using a 16mm bore diameter to suite my existing mandrels.  I wondered what the group thinks about thickness of the Ratchet Plate and the Anchor plate ?  Scaling from 12.7mm to 16mm gives something like 10mm and 8mm respectively .........

I've just looked at the drawings in Ivan Law's book and my Eureka. Don't bother scaling anything just make the ratchet sleeve with a 16mm diameter rather than 1/2". I've shown an M16 x 1 thread because it is a standard tap size.



Phil.
Phil Fern
Location: Marple, Cheshire