edge finder

[freemen]

Thanks, you just saved me 20$ from buying one on fleebay and now I can make 4 or 5 of them for different size collets. :bow:

 

[krv3000]

HI good work from bob

 

[El$syd]

Thanks for posting this excellent idea - absolutely brilliant, I hope to make several!
But I am surprised no-one makes these commercially!!!! ???

 

[petertha]

And the edge detection is really precise and easy to read, to my experience +/- 0.01mm (0.004in) ore even better is always reproducible. Achim

Hi Achim. That is such a neat device.

Did you mean 0.01mm = 0.0004"? (one more zero).

Is there a certain class or spec of bearing that should be used?

 

[pkastagehand]

I have always used either the wiggler edge finders (or the end mill and paper trick if I didn't want to remove the cutter and put in the edge finder). I don't see that it makes much difference except to the wallet whether I use old tech or new tech, and being a frugal sort (don't say cheap ;D) I like the old tech. If desired accuracy is reachable there is no advantage if you have to remove the cutter and put in the edge finder no matter what style you use. Even the ability to center on a punch mark instead of an edge is doable with "old" tech wigglers.

I recently made one of those ball bearing jobbies and will make some more as time and need demand since it would be nice to have different sizes for different jobs/collet sizes.

When people rush out to buy the "newest" gizmos I sometimes wonder if they have more money than sense. I'll agree that at times new can be better but many times it is marketing people creating a "need" that didn't exist until they created the new device to fill the "need". And if it makes more jobs and keeps the economy going it isn't all bad I suppose.

Paul (not quite a luddite but showing my age?)

 

[picclock]

I have some of the ball bearing type edge finders I made before getting a starrett type. One thing I found which made them easier to use is to paint the top bearing shield black and then use tippex to make white segments. This gives a much better indication as to whether the bearing is rotating.

However I jumped ship for a Starret for two reasons. Size matters ;D at least it does for me. The size of the end of a Starret edge finder is smaller than any of the ball race versions I made. This means I can get a centre off of any small hole >6mm dianeter., And then there's the other end. Its a concave conical shape and will allow one to get a centre position from any size hole <10mm or even a centre punch mark. When I first received it I wondered what I would use it for but its since proved its worth many times over. Its only as accurate as your fingers, misalignment being determined by feeling the difference between the shaft and the conical end. I can easily get to <1thou using this. Its easy to see the runout of toolholder just by rotating the spindle half a turn after alignment, so if you want to be really picky I guess you would set the position to the average of the two aligned readings.

Best Regards

picclock