How to identify carbide tips ?

[Richard.]

Which ones?

These
http://www.cutwel.co.uk/lathe-tools...k-carbide-turning-inserts-pc5040-grade-korloy

 

[grim_d]

Thought it might be, at £9 each it will have to wait until im next doing a cutwell order to try it out.

 

[Richard.]

I use the cheaper ones for roughing to size then finish it off with those bad boys to a mirror. In effect they don't do a lot of work taking a couple of light skims off the job so as expensive as they are they should last a long time unless I have a moment of madness and accidentally drive them into it.
It's happened before and no doubt will happen again

 

[grim_d]

I will get some in time, just don't want to order any on there own because cutwells shipping us quite dear.

In the meantime I have some KORLOY CNMG-AK H01 inserts on the way to try, same high rake Insert and chipbreaker but different coating, or uncoated? polished for alu. Ill give them a go and report back, keep them for alu if no good for steel.

I use mitsubishi vp15tf for roughing, cheap as chips on eBay.

Have some mitsubishi cermet tips too which I haven't got on well with and may sell.

 

[Richard.]

Be good to hear the results you get from the h01 inserts.

 

[addjunkie]

I thought the TCMT 11 quoted by hood sounded familiar. I had a rake today and found some that fit my boring bars. If you @cumbriasteve PM me your address Ill pop one in the post for you to confirm the size

 

[grim_d]

Be good to hear the results you get from the h01 inserts.

Got them today and had a very quick go with them. No good at all for steel, no better surface finish and built up edge almost immediately. Worked very well on aluminium as you might expect, no improvement in surface finish but no edge build up and better chip control, a long spring type rather than a big birds nest. They might even break if the speed was higher.

It will be interesting to some day compare them to the coated ones.

There is also the possibility I bought fakes.

 

[Newlands]

Although I only have the one damaged tip I would still like to know how to identify it when searching for replacements.

It is showing 10.03mm from point to point with a thickness of 2.54mm, looking on ebay there are just numerous numerical codes which mean nothing to me.

View attachment 112764

It's a bit late, but to me that looks like a TCMT 10 02 04. It might be a TNMG - N denotes a 0° relief angle whereas C is 7°, and G is a plain fixing hole whereas T is countersunk.

T = shape (triangle in this case)
C = relief angle (which some people call rake angle)
M = tolerance on the overall size, and the fixing hole if there is one
T = method of fixing and/or chip breaker, e.g. Plain hole, csk one or both sides etc.

The numbers are:
10 = cutting edge length
02 = thickness (02 is 2.38mm, 04 is 4.38mm for example)
04 = tip radius in mm, i.e. 0.4mm in this case

There are 3 or 4 other characters after this usually - which denote the type of cutting edge, L, R or N (neutral) direction of cut, plus a mfgrs code for the chip breaker type.

I use the Engineers Black Book 2nd edition to identify tips, and tool holders - very useful as you can buy cheap Chinese toolholders on eBay and then fit them with decent brand name inserts (also on eBay, but you have to be a bit careful that the inserts as well as the box they come in are the same brand!).

 

[cumbriasteve]

I thought the TCMT 11 quoted by hood sounded familiar. I had a rake today and found some that fit my boring bars. If you @cumbriasteve PM me your address Ill pop one in the post for you to confirm the size

@addjunkie I never got an alert to this kind offer, many apologies for the late reply and pm incoming.

 

[Newlands]

Toolholders use a similar system of numbering.
A boring bar might be something like S20RC TFPR10x
S = type of shank (S is plain steel, but could be carbide, or have a coolant hole etc)
20 = diameter of shank in mm
R = tool length e.g. R is 200mm, M is 150mm etc
C = clamping method (C is a clamp lock, S is a screw lock)

T = insert shape, same code used as for inserts themselves
F = approach angle (looking from on top, the angle the front cutting edge makes with the lathe bed)
P = relief angle of the toolholder
R = hand, i.e. Left or right handed
10 = cutting edge length of the insert, mm
x = mfgr number, could be anything.

The problem is that some manufacturers don't conform to this standard, or they do but they describe their toolholders by their own in-house names and the correct designation is hidden deep in the small print.

For anyone buying tools and inserts for the first time it is worth spending a bit of time standardising on one shape of tip, and buying toolholders that suit that tip, at least for the most common types of turning such as plain turning, facing off and boring. Obviously you can't do this if you want a thread cutting tool!
It's also worth bearing in mind that for jobs which need an unusual tool there is always HSS to rely on - form tools, cutting special threads that aren't 55° or 60° and so on.
And if you don't want to buy a little black book, then I've found that CarbideDepot have a fairly reasonable guide to inserts on line.

Edit -'I forgot to mention that the US uses a slightly different system to the metric system we use, so you have to stick to one or the other. Hence the Carbide Depot page has some differences. In fact, the little black book I linked to above comes in US or Metric editions - make sure you buy the right edition or you will never stand a chance of finding the right insert! It is also important if you watch any of the YouTube guys - Adam Booth abom79 for instance has done a good video on inserts, but describes the US system not ours.

 

[ukracer]

Not sure if this was the right thread.

But i found a cracking video on carbide v HSS

The second part...follow up might confuse you...it did the poster...lol

 

[Hood]

Good example of why I much prefer a DNMG to a CNMG insert, the CNMG often can pick up and trap swarf behind the cut and give the rough surface.
Regarding small depths of cuts with carbide, it is possible but I much prefer not to go below the nose rad of the insert for a cut, that was probably done in this instance although it is hard to be sure what the nose rad is. It kind of looks like 0.8mm and he was taking 0.635. Having said that it is still relatively easy to get a decent finish just by messing with the feeds.

 

[dobbslc]

Very interesting video that! The poor finish he got with the lighter cut is exactly what I've been having trouble with using TCT inserts.

 

[Hood]

Very interesting video that! The poor finish he got with the lighter cut is exactly what I've been having trouble with using TCT inserts.

What nose rad, type of insert, depth of cut?

 

[dobbslc]

Now you're asking!
I think its a 04 nose rad, a TPMT insert and only light cuts as my machine doesn't really like heavy cuts. The tool holder it a Sandvik one I got nearly new for a fiver!
Top speed is 1400 RPM and a lot of the bits I make are under 2" diameter. I've not had much luck with HSS tooling to be honest so went with the inserts.

 

[Hood]

TPMT should be one of the easier inserts to get a good finish with as they are a positive insert and usually have a fairly sharp edge design to the chip breaker. Is it a decent brand or a cheapo?
BTW 1400RPM is plenty, I very rarely go beyond 1000rpm on my lathes.

 

[dobbslc]

I'll have a look for the makers name, I bought a box of 10 for about £35 at the model engineers show so I hope they are a good make!
That Sandvik tool holder came with an insert that cut really well until i ******** it.... I couldn' identify it to replace it though

 

[Hood]

I'll have a look for the makers name, I bought a box of 10 for about £35 at the model engineers show so I hope they are a good make!
That Sandvik tool holder came with an insert that cut really well until i ******** it.... I couldn' identify it to replace it though

Well it is around about the price you would pay for a decent enough make but.....