Vertical Shear Lathe Tooling

[Jon GibbsParticipant @jongibbs59756]

Hi All,

I just watched MrPete222's recent video pair on vertical shear lathe tooling and made a LH and RH pair – brilliant!

If you haven't seen them they're worth a watch **LINK** and **LINK**.

I've been struggling to get a decent finish on EN3B for some time but this really solves most of my woes and for finishing cuts seems hard to beat.

HTH

Jon

[Jon GibbsParticipant @jongibbs59756]

[Ady1Participant @ady1]

They use the same kind of fine finish tools on shapers but the cutting part is convex (bulges out slightly)

[Jon GibbsParticipant @jongibbs59756]

That's interesting – I'm pretty familiar with shear scraping and shear cutting in woodturning which has pretty much the same action.

Have you seen anything similar for boring bars or for facing?

I'm assuming the slightly rounded nose version might help for facing but I've been wondering whether a boring bar which takes round toolbits could be used with the right grind to shear cut the inside of bores?

Jon

[Ady1Participant @ady1]

Would be very handy for boring purposes

[Neil WyattModerator @neilwyatt]

I can't remember who suggested a similar tool in ME, many years ago. The tool was a cylindrical toolbit ground to half-way with very slight rake back from the cutting edge. In use it is angled across the work and used for shaving cuts just like the one you've linked to. Apparently the 'swarf comes off like cobwebs'.

I must have a try of one or the other design!

Neil

[Russell EberhardtParticipant @russelleberhardt48058]

If I remember right Neil, it had the cutting edge at about 45° rather than 80° to the horizontal. Or perhaps that was another one.

Russell.

[Neil GreenawayParticipant @neilgreenaway71611]

I think the round toolbit you are talking about was described by LC Mason in "using the small lathe" book.

Neil

[Neil WyattModerator @neilwyatt]

I think you are right Russell, though teh principle is essentially the same – a tangential cutting edge (rather than a tangential toolbit).

Neil – that may well be the original source, although I haven't read that book (yet!)

Neil

[Ed DuffnerParticipant @edduffner79357]

I was thinking this could be used for fly cutting surface finishes using a round cross-section and mounting the tool at a low, inline angle like a tangential setup. I'll try to have a go at this when it warms up a bit.

 

Ed.

Edited By Ed Duffner on 06/01/2015 14:37:39

[VicParticipant @vic]

I made a Tangential flycutter. Works well enough but nothing special. I prefer the more normal setup or round carbide insert.

[VicParticipant @vic]

More on the shear tool on this page.

http://conradhoffman.com/advancedsharp.htm

[chris stephensParticipant @chrisstephens63393]

Hi Mr Editor, I first saw the round shearing tool in a mid fifties ME, so your esteemed mag can take the credit, perhaps not, as some Victorian probably came up with it first. I have used one ever since I read about them and they are pretty damn good at making very fine wire wool, oh, and a fine finish too.

Re that American video chap, can't help but feel he thinks he is still talking to school children, instead of second childhood children! He is far too dogmatic for my taste but to be fair you can learn a few basics learn from him.

chriStephens

[pgk pgkParticipant @pgkpgk17461]

Posted by chris stephens on 06/01/2015 15:33:42:

…

Re that American video chap, can't help but feel he thinks he is still talking to school children, instead of second childhood children! He is far too dogmatic for my taste but to be fair you can learn a few basics learn from him.

chriStephens

He spent his career teaching high school machine shop…

[chris stephensParticipant @chrisstephens63393]

Hi Pgk Pgk, I thought that was what I wrote, school children.

Edit, on further thought, from my limited experience of Americans they seem not to  grow out of childhood, and its fantasies, till the undertaker comes a-calling and reality finally kicks in. Got to love them all the same, as I'm waiting my second childhood, still being in the first.

c

Edited By chris stephens on 06/01/2015 17:44:40

[Jon GibbsParticipant @jongibbs59756]

Posted by chris stephens on 06/01/2015 17:30:08:

Edit, on further thought, from my limited experience of Americans they seem not to grow out of childhood, and its fantasies, till the undertaker comes a-calling and reality finally kicks in. Got to love them all the same, as I'm waiting my second childhood, still being in the first.

Sorry Chris, have to take issue with that generalization about Americans. 'Fraid to say your experience is clearly limited on perhaps more than one issue.

I appreciate him taking the time to share his experience even if you do find his approach dogmatic.

Jon

[Ed DuffnerParticipant @edduffner79357]

Posted by Vic on 06/01/2015 14:56:51:

I made a Tangential flycutter. Works well enough but nothing special. I prefer the more normal setup or round carbide insert.

Hi Vic,

Exactly what I was thinking of but with the tool bit rotated approx' 90° (top of the bit turned towards the viewer in your picture), using the longer edge to skim the work.

Ed.

[chris stephensParticipant @chrisstephens63393]

Hi Jon, Take all the issues you like, the smiley face shows I was poking fun and not meant to be taken too seriously.

With regard to Mr Pete, I wont call him Tubal Cain as it is disrespectful to our one, I did in my first post say you could learn basics from him. That is a sort of praise from me, dogma though has no place once you have learnt how to be safe in a workshop, as it stifles ingenuity and progress.

As for the colonists over the pond, one only has to look at their obesity rates if you want evidence of fantasy being brought to a conclusion by the undertaker. The fantasy is that there are no consequences to their life style choices. I still have great regard for the few Yanks I like to call friends, by the way they are the ones with a sense of humour. even if they will have avoidable health problems as the years go by.

chriStephens

PS never take anything i say too seriously, as I never do.

[VicParticipant @vic]

Posted by Ed Duffner on 06/01/2015 18:07:42:

Hi Vic,

Exactly what I was thinking of but with the tool bit rotated approx' 90° (top of the bit turned towards the viewer in your picture), using the longer edge to skim the work.

Ed.

I'll have to give that a try sometime Ed!

[HasBeanParticipant @hasbean]

I ground this one up a few years ago

I seem to think it worked well enough but I gave up with it for reasons I can't remember

I might give it another whirl now the topic has resurfaced.

Paul

[clivelParticipant @clivel]

Posted by chris stephens on 06/01/2015 18:37:47:

As for the colonists over the pond, one only has to look at their obesity rates if you want evidence of fantasy being brought to a conclusion by the undertaker. The fantasy is that there are no consequences to their life style choices. I still have great regard for the few Yanks I like to call friends, by the way they are the ones with a sense of humour. even if they will have avoidable health problems as the years go by.

At the risk of taking this thread even further of topic, but if only to show just how dangerous generalisations are, and why people in glass houses shouldn't throw stones – The top three countries with the highest obesity rates are the United States, Mexico and the United Kingdom.

[Johnboy25Participant @johnboy25]

Neil… "Apparently the 'swarf comes off like cobwebs'."

I was wondering if this is how steel wool or wire wool is produced. Just a thought… But seing the YouTube clips from Mr Pete with my limited experience, I found that useful to know. I've come across some materials that I could never get a satisfactory finish. I've learnt something useful today!

Regards

John

[Paul LousickParticipant @paullousick59116]

A good video on Youtube by Tubal Cain about vertical shear tools

Paul.

[MuzzerParticipant @muzzer]

Looks very similar principle to the skew chisel used in wood turning. Used one of these a couple of times and it frightened the crap out of me. Best used on small diameters where it is easier to get the angle right so that the edge is tangential and the contact / cutting point is near the centre of the cutting edge. Gets more difficult the larger the diameter of the work piece is. If you get it wrong you better be wearing your best rubber pants – and head / eye / hand protection.

Very sharp HSS tools can produce very fine "bum fluff" swarf and smooth finishes if used carefully (I'm thinking that bum fluff is better better than angel hair!), so I suspect you can get similar or possibly even better finishes with carefully prepared "standard" tooling.

With a suitable holder you could use an insert to achieve this type of cutting – and it would use an edge that is rarely used or even thrown away unused once the corners have been blunted or chipped. The inserts for aluminium are often highly polished and would be good for steel in this application.

Murray

[WindyParticipant @windy30762]

Is this the same as skiving in one of my old turning books.

Paul

[Author]

Posts