Carbide Insert Quality

[Hugh GilhespieParticipant @hughgilhespie56163]

[Hugh GilhespieParticipant @hughgilhespie56163]

I have been using some Glanze lathe tools with the small (6 mm ?) CCMT inserts from Chronos. They give a very nice finish on EN1A and I would like to make more use of them and buy in half a dozen inserts.

 

 Looking in various catalogues there are loads of different suppliers for these inserts and with very varying pricing too. I am interested if people think that there is much detectable difference in the quality of the inserts from different sources? I am only using them on a 5 inch lathe and normally not cutting more than about 20 thou maximum so should I stick with the cheapest or go for super duper unobtanium coated varieties?

 

All advice gratefully received.

 

Thanks, Hugh

[Engine BuilderParticipant @enginebuilder]

I would recommend Sumitomo tips from Neville Carter. I wouldn't use anything else now. They are more expensive but in my opinion vastly supieror to anything else. They are most suitable for our size machines and have a smaller tip radius than most offered.

http://www.carterprecisiontools.co.uk

Edited By Engine Builder on 08/09/2010 21:59:15

Edited By Katy Purvis on 01/06/2015 09:37:55

[Ian S CParticipant @iansc]

I think my tips are by Sandvic, but for very small tips I use the tips on old cicular saw blades brazed on to a steel blank,8.8 metric bolts are a good start, grind or mill, or file to shape, and silver solder is all you need. I would think these would be handy on the smaller lathes, and once you find the saw blade, cheap. As for the sandvic tips the ones I use (16mm triangle no hole), come with 3 or 4 different tip radii.Ian S C

[KWILParticipant @kwil]

The  smallest radius tips are fine for special purpose tight corners but  they are vunerable due to their small radius and cannot produce the smoothest surface, being in effect a small thread producing tool!

[Axel BentellParticipant @axelbentell]

go SECO go! (from my hometown!)

[Ian S CParticipant @iansc]

Kwil, I use mainly.5 or1mm radius tips the same tip suit the 50mm face cutter in the mill.Ian S C

[KWILParticipant @kwil]

Ian

 

I agree with you, but these tiny tips are down to 0.1mm!!

[Anonymous]

I have a couple of Glanze boring bars, which I am pleased with, but I found the supplied inserts to be very poor. Indifferent surface finish and easy to chip. I bought the bars some years ago, so may be they’ve upped their game on the inserts.

 

I buy inserts from Greenwood, J&L and from the local professional tool supplier, but I’m not tied to any particular manufacturer. I find that the special polished inserts from Greenwood are excellent on aluminium. The Greenwood general purpose inserts work well on brass, bronze and 303 and 316 stainless. On steel they also work well, BUT do need to be run fast; a surface speed of at least 400fpm.

Regards,

 

Andrew

[John OlsenParticipant @johnolsen79199]

Well Axel your next mission is to find a way to keep us all in cheap tips from Seco…

 

 

Tack så mycket

John

[chris stephensParticipant @chrisstephens63393]

I second ,or is that third, the recommendation of Sumitomo tips. 

I personally prefer triangular tips as I am such a meanie, three edges over two useful ones!

Kwil, in this case you are slightly misinformed about small tips “thread producing” tips, unless of course you are using “roughing” feed speeds, as opposed to “fine finishing” ones. The very small tip radii are only meant for very fine finishing (at small feed rates) at which they excel.

 

The beauty of small radius tips, on our size lathes, is that they require very little effort to cut metal. This free-cutting shows itself in a lack of work piece and/or tool deflection, resulting in a better and more consistent surface finish. As I am sure most of us would agree that only a good  “smooth” surface can be measured, with any hope of accuracy, and this finish can be easily achieved with Sumitomo small radius tips.

 

For those unfamiliar with the tips in question, they are not Tungsten Carbide but Titanium Carbide, which Sumitomo call “Cermet” (Ceramic+Metal).

 

Unlike many tips which work marvellously at industrial speeds and feeds, these tips can  work at very small depths of cut, which is very useful for cutting that “last few thou” to get the size we want.

 

If there is a trouble with Sumitomo products, it is that that they keep changing the chip breaker designations. For any tip they might make three different chip breakers, not to mention tip radius, just as you get to remember which one you want, they bring out a new catalogue with new designations.The chip breaker is very important on these tips, as it denotes the depth of cut at which they work best. Having said that, I am sure that Carters  will supply the right ones for “our” needs.

 

To sum up, if you have tried Carbide tips and wondered why people bother with them because of the lousy finish they can give on small lathes, try Sumitomo they will be a revelation.

 

chriStephens 

Oh, by the way , I would not be without my Tangential tool, but there are times when even very easy sharpening, is out classed by no sharpening! 

 

[HasBeanParticipant @hasbean]

Andrew I’ve found very much the same as yourself but also use the Greenwood ‘polished’  inserts for fine finishing on steel, which work a treat if carefull. The general purpose tips work fine for me on most things except mild steel.

 

For general use on mild steel I use a Cermet made by Mitsubishi (grade NX2525) which was recommended as an alternative to the Sumitomo tips which, at the time, I could not get hold of (they are also a little less fragile in my opinion)

 

Paul

[Anonymous]

Hi Paul,

 

Thanks for the tip regarding the use of polished inserts on steel, I’ll give it a go. And yes, I know there’s a pun in there.

 

For ordinary steel, such as EN1A or EN3 I find you really have to run the ordinary carbide tips at high surface speeds to get a good finish, whereas other materials, including stainless, seem to be more forgiving.

 

Regards,

 

Andrew

[Hugh GilhespieParticipant @hughgilhespie56163]

I took the advice offered and bought some Sumitomo tips from Neville Carter and I have to say they are the dog’s whatsits. I used a Glanze 6 mm CCMT tip to turn some EN3 and the results were horrible. Tried all sorts of different feeds and speeds and it was still horrible, it looked like a screw cut gone wrong. So, I tried one of the new Sumitomo tips and what a difference! Lovely smooth surface and I was able to take very fine 0.25 thou cuts and keep a good surface. My thanks to everyone for some very helpful advice.

 

Regards

 

Hugh

[chris stephensParticipant @chrisstephens63393]

Hi Hugh,

A-Ha, another convert. They are special aren’t they?

If you are in the mood for taking advice, try a tangential tool holder, they are much cheaper to run, keep the Sumitomo for bulk /tough metal removal or special needs when nothing else will do.

chriStephens 

[BogstandardParticipant @bogstandard]

Basically I only use just two types of tips in my general purpose lathe tooling, and both have a chipbreaker form. The first is the CCMT06 for my normal tooling and the RCMT06 for my profile tool.

 

But being a cheapskate, after they have gone dull from normal use, I very gently lap the top face on a well wetted very fine diamond lap, and they are then perfect for use on brass, as doing that forms a zero top rake cutting face on them. After a few years of use, I have yet to do them a second time, but I suspect it can be done.

 

Waste not, want not.

 

Bogs

Edited By Bogstandard on 29/10/2010 04:49:34

[Engine BuilderParticipant @enginebuilder]

Glad you like them Hugh.

I have made up a tool holder so the obtuse angle can be used. I use this for roughing out and interminent cuts.

David

[GoCreateParticipant @gocreate]

Often resort to HSS or even CS to get a good finish!

 

Someone please point me in the direction of Neville Carter, first I have heard of him.

 

Many thanks

Nigel

[Engine BuilderParticipant @enginebuilder]

http://www.carterprecisiontools.co.uk

Edited By Engine Builder on 29/10/2010 14:53:02

Edited By Engine Builder on 29/10/2010 14:53:25

Edited By Katy Purvis on 01/06/2015 09:37:07

[adyParticipant @ady]

I’ve found that a teeny bit of negative rake on a carbide tip can make it a lot less fragile.

[Author]

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