Diamond tool holder.??

[VicParticipant @vic]

Same here, I've been meaning to make a left hand version Chris!

If you use a four way toolpost consider this: If you get the design right and critically the thickness of the tool holder then you can quickly and easily set the tool height by turning the Toolholder upside down on a flat surface and dropping the cutter until it touches then clamp in place. I hope this makes sense! In essence the top edge of the tool holder is exactly on centre height of your Lathe when it's in the tool post. I hasten to add its not my idea but it's too good not to pass on. I'll be incorporating this idea on my next one. This really is another example of why it's such a good idea to make your own tooling sometimes. Let's see pictures when you've made yours!

[Neil WyattModerator @neilwyatt]

The Wimberley tool-holder arrived a few days ago,

I've now had a chance to have a good look at the toolholder and read through the booklet, which is commendably comprehensive. I haven't used it yet as my lathe won't take a 1/2" shank tool, so I either have to modify one of my QCTP holders or make a new one. As I plan a batch of toolholders in the near future, I will probably make one especially for it, as a wider, as well as deeper, groove will help minimise overhang.

I am struck with the feel and look of quality; it's a beautiful, well finished casting machined to an excellent finish. I'll probably bring it to MEX in my pocket…

Neil

[VicParticipant @vic]

Pictures!

[Neil WyattModerator @neilwyatt]

Sorry Vic,

I thought I had posted a link to the Wimberley website. Below is a picture of a well-used example from the site.

Neil

[Russell EberhardtParticipant @russelleberhardt48058]

Can anyone explain why these wimbly wobbly or tangential toolholders should perform any better than conventional HSS tooling?

As far as I can see, the only advantage is that they are easier to regrind. However if you wish to use different rake angles to suit different materials that advantage would seem to disappear as it does if Howard has to dig out his Worden to regrind them.

I'll stick to grinding my own, one set for brass and another for mild steel plus a few specials. Does that make me a Luddite?

Russell.

[HowiParticipant @howi]

Posted by Russell Eberhardt on 06/12/2014 14:00:42:

I'll stick to grinding my own, one set for brass and another for mild steel plus a few specials. Does that make me a Luddite?

Russell.

Yup! Afraid so……….

I have found my home made tangential took holders (r/h and l/h) will cut equally as well on ALU, brass and steel and give a good finish and at less than a fiver each including 1/4 in HSS cutting bits. I thought £75 each for the diamond version more than my wallet could handle – though I may have been tempted at half that price. Still, I get a kick out of using something I have made rather than bought.

[VicParticipant @vic]

Yes, I've found It works for most materials. Not sure it's any better than other tools although I do like using it. Cost was a primary reason for me to try one. Insert tooling is great but the tips can start to work out expensive. The Tangential tool uses short pieces of inexpensive HSS and grinding is easy with the jig. Setting centre height is also a breeze.

[Neil WyattModerator @neilwyatt]

Russell,

The main advantage, as far as I can see, is that both avoid the necessity for grinding two faces that meet at a cutting edge, as is essential if making a standard knife tool. This means that creating side clearance and top rake (other than on a flat-topped tool for brass) is always rather tricky and tends to leave the tool undersize. This is a major boon, not just to a beginner, but the ease with which a standard and effective geometry can be achieved quickly means sharper tools and a happier life for all

Neil

[Russell EberhardtParticipant @russelleberhardt48058]

Posted by Neil Wyatt on 06/12/2014 16:05:44:

The main advantage, as far as I can see, is that both avoid the necessity for grinding two faces that meet at a cutting edge, as is essential if making a standard knife tool. This means that creating side clearance and top rake (other than on a flat-topped tool for brass) is always rather tricky and tends to leave the tool undersize. This is a major boon, not just to a beginner, but the ease with which a standard and effective geometry can be achieved quickly means sharper tools and a happier life for all

Yes, I can see that the tangential tool is easier to grind but if you want to get the correct top and side rake it isn't quite as straightforward as using the supplied grinding jig.

The Wimberley seems to require two ground facets and gives fixed rake angles unless you grind a third which is then the same as grinding a conventional tool. Having said that, grinding back rake does give a problem after many regrinds so I have made this holder:

Russell

[Neil WyattModerator @neilwyatt]

The Wimberly is strictly meant to be used with fixed rake angles. The clever bit is that the side and front rake are equal so it faces and turns with equal facility. The lengthy manual makes it seem harder to sharpen than I suspect it really is. Perhaps a key advantage is how little material you have to remove.

Your holder effectively is a 'Semi-Wimberly' only giving rake in the 'facing' direction.

Neil

[chris stephensParticipant @chrisstephens63393]

Hi Russell, it is a myth that you need different rake/clearance angles for different materials, well it is for the average home user where a few seconds less between sharpenings is of little or no importance. Metal should be cut the way she likes to be cut and that usually means a fair amount of rake, where different rake angles come in the equation is in making the edge stronger hence last longer. It was in industry, where seconds saved might mean profit instead of loss, that all those rake/clearance angles came in but industry gave up on HSS decades ago so feel free to ignore the outmoded, but oft repeated, information.

A single Tangential tool will do most turning and facing jobs, and without having to swivel the tool post between those operations, except for jobs where HSS is less than ideal like abrasive cast iron skins or case hardened steels etc. Unless of course you put a piece of solid carbide in instead of HSS but that is another matter.

As for being a Luddite not at all, it makes you more modern than you thought you were, Tangential tooling goes back to mid Victorian times before HSS came about and high carbon steels were the in thing for cutting tools, and by the way another reason for various rake/clearance angles to protect the cutting edge.

Perhaps Neil could commission an article on the history of lathe tools, it might prove interesting to the self taught homeshoppist and give them food for thought for reinventing lost but still, potentially, useful ideas.

chriStephens

[VicParticipant @vic]

Very interesting what you say about rake angles Chris. I've never used different angles for turning tools, not even brass and not had any problems with finish or anything else. I guess folks just repeat what they've heard or read in old books. Perhaps it's time for a new reference book for model engineers.

[David Carpenter 4Participant @davidcarpenter4]

For testing of the Diamond tool holder see here.

[OuBallieParticipant @ouballie]

The one BIG advantage of using a tangential tool was shown to me some time ago, and which I posted about, when in BrainFade mode, I turned the Saddle Handwheel anti-clockwise with lathe running and the bit jammed into the work.

Well, you can imagine my relief when nothing bad happened, with just the bit being pushed down the holder away from the work.

Another big advantage if the ease of keeping it sharp.

Been taking 3/4mm cuts with ease on BMS and still experimenting.

Can't wait to get the FeedRodMotor finished, but being sidetracked as usual.

The tangential made mincemeat of turning the bronze bearing for the Tom Senior Overarm.

Geoff – My tool of choice now.

Edit: Posts now take ages to upload. Anyone else experiencing this?

Edited By OuBallie on 07/12/2014 10:15:59

[Russell EberhardtParticipant @russelleberhardt48058]

Posted by chris stephens on 07/12/2014 02:01:06:

Hi Russell, it is a myth that you need different rake/clearance angles for different materials,

Hi Chris, it's all too easy to dismiss years of theory and experience. True the rake angles affect tool life between regrinds but they have other effects as well. A well known one in ME circles is that for brass if there is much rake the tool can be dragged into the material and give a poor finish. A fine cutting angle (high rake) produces less cutting force and, for less rigid home machines, is less likely to deflect the tool or workpiece and is thus ideal for fine finishing and slender workpieces. Plastics are another thing altogether. Treat hard plastics like brass and for softer plastics use high rake angles and clearance angles.

Of course, if you're happy with the results you get with one tool form for everything that's great.

Russell

[Russell EberhardtParticipant @russelleberhardt48058]

Posted by David Carpenter 4 on 07/12/2014 09:42:11:

For testing of the Diamond tool holder see here.

For a more scientific test it should be tested alongside other types of tooling for comparison. Just using it in isolation and saying that it works is not much of a test.

Russell.

[VicParticipant @vic]

Posted by David Carpenter 4 on 07/12/2014 09:42:11:

For testing of the Diamond tool holder see here.

Good link David, thanks for posting that!

I don't think anyone will be doing any scientific testing of production tools dropped over a hundred years ago Russell but one may hope!

[Michael Cox 1Participant @michaelcox1]

What impresses me most about tangential tool geometry is that it seems to cope with large depths of cut more easily than conventional tool geometry. On my minilathe I can take a 1 mm deep cut without too much trouble using the tangential tool.

I also have a small X1 mill. This has only a 150 watt motor. Using a conventional fly cutter it would really struggle to make a 0.1 mm cut in steel. I tried all sorts of tip geometry to try to improve this. I then made a tangential tool flycutter (see: http://mikesworkshop.weebly.com/tangential-tool-flycutter.html) and the difference was amazing. Cuts of 0.4 mm were possible.

What I cannot figure out is why the tangential geometry allows these much better depths of cut. I have tried conventional flycutters that present the tip in exactly the same way to the metal being cut as the tangential tool cutter but the depth of cut ( and surface finish) is always inferior. I think it must be something to do with the rigidity of the tangential tool mounting.

Mike

[Cornish JackParticipant @cornishjack]

One of my last purchases before the workshop succumbed to the North Sea 'surge' was a Diamond tool-holder. Quite impressed with the results. Just previous to that I bought a used Myford tool holder which I have not seen elsewhere. Presented in a 'tailored' box, it was approximately 2" x 1" x 1/2" with an angled through hole in one corner to take 'Eclipse' type round HSS rod. The end was ground to match the surface of the tool-holder, providing clearance and rake and making height setting particularly easy. Again, very easy to sharpen, (single flat surface) and the results were superb (by my standards!!). As said above, not seen elsewhere nor have I read of anyone else using them.

Rgds

Bill

PS First bricks laid for the house rebuild yesterday!!!

[Michael Cox 1Participant @michaelcox1]

Sorry for the multiple posts. As Geoff was saying a couple of posts back you hit the post button and nothing happens. I kept hitting the button in the belief that nothing had happened and ended up wit three postings. Can one of the moderators remove the excess postings to leave just one?

Thanks

Mike

[David Carpenter 4Participant @davidcarpenter4]

Posted by Russell Eberhardt on 07/12/2014 10:30:56:

Posted by David Carpenter 4 on 07/12/2014 09:42:11:

For testing of the Diamond tool holder see here.

For a more scientific test it should be tested alongside other types of tooling for comparison. Just using it in isolation and saying that it works is not much of a test.

Russell.

Doesn't pretend to be scientific, just practical.

For even better results see here.

[Tony Pratt 1Participant @tonypratt1]

Posted by chris stephens on 07/12/2014 02:01:06:

Hi Russell, it is a myth that you need different rake/clearance angles for different materials, well it is for the average home user where a few seconds less between sharpenings is of little or no importance. Metal should be cut the way she likes to be cut and that usually means a fair amount of rake, where different rake angles come in the equation is in making the edge stronger hence last longer. It was in industry, where seconds saved might mean profit instead of loss, that all those rake/clearance angles came in but industry gave up on HSS decades ago so feel free to ignore the outmoded, but oft repeated, information.

Hi Chris,

I beg to differ with your sweeping statement as quoted above. If you only wanted to do a bit of garden engineering of course any tool geometry will do.

If on the other hand you are interested in getting the best out of your lathe you will have to pay some attention to tool shapes etc., no one with any modicum of mechanical aptitude would expect one lathe tool to machine copper, brass, mild steel, plastic, aluminium & silver steel with universal efficiency.

Tony

[chris stephensParticipant @chrisstephens63393]

Hi Tony, and I beg to differ, as I stated for home user, for in industry HSS doesn't even show on the radar any more. I must assume that you have not yet tried a tangential tool as if you had you would not have dismissed my statement in such a cavalier manner. One tool really can do for just about any metal or plastic, save for those where HSS is inappropriate as stated in earlier post. As for getting the best out of your lathe, I tend to think you might have that backwards. I really do urge you to have a go with one, they are NOT all hype, and, as anyone who knows me will doubtless attest, I do have a "modicum of mechanical aptitude". I also have an enquiring mind and am willing to try anything new, old or different to improve my turning, not quote the same old guff that has been passed down the line since who knows when, at least not without proving it for myself first.

What I hope we can agree on is that there are numerous ways of doing just about anything and if you get the results you set out to achieve, then that is all that matters. I have watched some very experienced proffesional turners who turn things down to a couple of thou oversize and then file and emery to size, I seem to be able to turn to the size I want and get a good finish, though in truth I might polish with grey scotchbright to finesse the surface slightly. Some methods are better than others for sure, and not all of us have the same equipment or experience, so we have to make the best of what we have. My mantra is the more I know, the more options I have. That goes for tooling too.

ATB

chriStephens

[VicParticipant @vic]

Well said Chris. This is pretty much what L.H.Sparey says in his book "The Amateurs Lathe". He says even production shops eventually realised they could get the job done with only a few types of Lathe tools. Are there really folks out there with hundreds of basic Lathe tools with slightly different grinds or is it just folks repeating outdated information? When I first started out I saw all those late 19th century and early 20th century lathe tool charts and was thoroughly confused. Especially as so many of them contradicted each other! I gave up and learned to grind my own tools with a profile that worked. I soon found out you only need a few different tools. As a hobbyist I'm by no means an experienced machinist but I have managed to turn quite a lot of different materials on my modest Lathe with largely the same tools.

[MuzzerParticipant @muzzer]

Obviously there's nothing magical about a tangential toolholder that somehow allows one set of cutting angles to work for all materials. If you were to try machining brass with a tool that is ground for light alloys, you'd want to be wearing your best rubber pants. It's possible you could get away with it if you take tiny cuts and have your slides nicely nipped up but why would you bother? With a tangential tool, you can have a toolbit ground for brass etc (zero top rake) and one for light alloys (perhaps 20 degrees or so) and swap them over in seconds.

Indexable tooling is pretty rugged and forgiving but even so, they have quite different cutting angles according to the material being machined. Same with HSS twist drills for brass (slow or zero helix) and light alloy (fast helix).

I don't have a tangential tool myself, so perhaps I'm not qualified to comment!

Murray

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