Indexable tool insert replacements

I'm at the point of needing to replace the inserts on my lathe tools.

I have identified the sizes:

CCMT060204, DCMT07204 and TCMT1102.

My question is "what is the difference in brands?"

There seems to be a huge range of prices for what seems to be similar tools.

Interested to hear peoples views on this.

Dave

Simple quality, that is grade of carbide and binder, edge sharpness wether produced by the die or final grinding. Professional tips come from the likes of Sandvik, Seco, Kenametal, etc. Non professional from India, China etc. That being said I find cheap is adequate for my use. Interesting YouTube videos can be found on manufacture of tips for more information.

Dave,

My view is that it is a lottery - from more than one aspect.

Cheap may be cost effective for some, but not for others.

Some tips on the market are substandard.

Some are possibly good (ends of production runs).

Some may be perfectly good due to a production over-run.

Commercial users (as in high precision, high volume).

They could not tolerate less than full spec devices due to service life expectancy, production losses due to out-of-spec output etc.

High precision tooling/machines cannot justify running cheap, possibly substandard tips. These tips in these machines are very reliable and their longer life justifies the choice.

Commercial users (as in precision, but not so high volume.

These users demand quality which is reliable and suitable for purpose. The certainly would not buy the cheapest on the market.

Tips need to be predictable in use.

Now to hobbyists.

Depends on the individual to a greater extent.

Some may consider tips as cheap disposable items. Others may not be quite so rash with their disposables.

Their machines are less likely to be of the same quality of the commercial users. Some are even likely to only run the tips below their minimum optimum operational norms.

Some use tips that are designed for other duties, but are found to work very satisfactorily for the hobbyist (use of polished tips aimed at aluminium being used for harder metals.

Hobbyists are not usually counting time for machining operations. As such they often run at very slow removal rates.

Me

I go for reliable suppliers for ‘middle-of-the-road’ quality from reliable UK suppliers. I don’t use that many, but would hate to get a batch of brittle/poor wearing/dud tips. I would be questioning if it was the operator or the cutter - until I could work it out for certain. If the tips are of known origin, I can be confident that the operator needs to change something!

Best quality tips would be wasted on me.

I like to be able to sharpen my cutters, if possible. I don’t often do it for inserts but I do have some brazed tipped tools which get re-faced.

Personally, I think I prefer my ‘diamond tool holder’ for many operations - a chunk of HSS or crobalt - both of which can be ticked up quite easily on a regular basis. They work out cheap/new cutting edge!

As stated above for hobby use it becomes a challenge due to high cost of branded quality tips. I have used most brands with good results and also had some good cheaper ones as well. I am no longer spending 10 hours a day at the machine so can't justify costs anymore.

What I will say is try a few "GT" inserts. ie change the "MT" (moulded tip) for "GT" (ground tip) these are made for aluminium but give excellent results for light cuts on steel producing a good finish.

The thing with inserts is "What You Buy Is What You Get". So if this weeks unspecified but correct size E-Bay bargain doesn't work on your machine doing your jobs its money wasted.

I suspect much of the trouble folk have with inserts is purely down to buying one that won't perform for them. Either due to machine limitations of operator methods.

My rule is never to buy anything whose design operating conditions aren't available. The good brands have thier catalogues on line so you can easily look up how the beast is supposed to be used. Apparently similar inserts may be designed to be driven very differently. Not to self :- do not read metres / minute cutting rate as ft / minute, especially if its already verging on scary fast.

The sharp, polished inserts intended for use on aluminium are, justifiably, well known for working well at home shop lathe, HSS level, speeds and feeds but they tend to be a bit more delicate on the edge than the heavier duty versions.

Many inserts have sweet spots outside the design operating range where they work well on many combinations of material at lower cut and feed rates. Its disappointing when they drop out of the sweet spot though. Had me scratching my head for awhile the first time I encountered it and had to re-set speeds to finish a job with a good surface. This is where following well meaning internet or forum "This one works fine for me" advice can be a bit fraught. Folks machines and methods differ. Also insert design is continuously being refined so same number but a few years old may well be sufficiently changed from the current version to have a different sweet spot when used outside "book" parameters. I have a couple of boxes of the same Sandvik type number whis exhibit this.

There are good brand inserts made specifically for lower rates of cut on manual machines. I believe SECO used to make a decent general purpose range.

Clive

From amateur perspective whatever you buy will sereve, one short time, another for longer.. Chinese inserts from Ali, particularly if you don't go for the cheapest are of outstanding quality these days and together with postage they cost chaper than p&p from European manufacturer.

I have bought two handfuls of these @ $0.2 each. Free p&p was offered. Outstanding quality, in various tests run up to 1200 rpm they perform as good as Sandvik when used for stainless. Should last for life.

Hi Dave,

I have used inserts from Sandvik and Iscar, expensive but very good. I found a supplier that also had inserts they imported themselves (I don't know from where) at half the price. I tried them and found they were as good as the Sandvik or Iscar insert I had used earlier, so that is what I buy now.

Thor

These are just the sizes, ferrous ones are also subdivided by grades that vary between makers, some are more expensive for interrupted cuts and some not and break easily. Some have more carbide in them than others etc etc

What is a 'Brand'? We hope it means the maker has an established reputation which it's determined to protect by applying rigorous quality control to a well-specified and well-made product. My view is the idea is built on sand.

The notion dates back to Beechams' Powders. Mr Colman's Mustard and Mrs Pott’s Patent Cold Handle Sad Irons. Beware imitations and available at all good emporia. Mr Beecham was one of the first patent medicine sellers whose products actually worked. Today the brand is owned by the multinational GlaxoSmithKline; nothing wrong with their Aspirin, but is it worth the extra money? If the brand-name makes you feel better, yes!

Brand-names cover a multitude of sins. Many a well thought of but bankrupt company recovered cash for their creditors (such as the Inland Revenue) by selling their Brand names to whoever wanted them. Some sold on brand-names are maintained, others are used to flog cheap goods, and a few zigzag. Skoda started as a highly respectable engineering company, sagged badly under Communism, and has since bounced back as an effective car maker.

Brands go up or down in value and are faked and imitated as well as genuine. Some brands are low value because they become fashionable: in my youth Marks & Spencer’s jeans were looked down on by fashion conscious friends despite the trousers being identical apart from the label. Maybe they were made in the same factory from the same cloth by the same workers on the same machines…

Brand names are linked to another hazy idea – ‘quality’. Engineers think in terms of ‘Fit for Purpose’ and ‘Value for Money’, considering how long tools must last in order to pay for themselves and make a profit. Doing the sums leads professional buyers to different answers depending on the circumstances. As downtime is expensive, the answer is often to buy the best tools available. But as buying the best tools available is eye-watering costly, the answer might be the other extreme – ordering expendable tools only intended to last long enough to do the job. The economics often depends on the machine: stopping production for a manual tool change and waiting for a costly skilled man to fix it suggests reliable tools. But machine centres often feature magazine auto-changers that quickly swap tools automatically. With these it’s often cheaper to use lower specification cutters. The skilled man is replaced by a machine minder who just refills the magazine.

Assuming the manufacturing process is working correctly, the specification of inserts depends on the amount of carbide in the matrix, plus any added processing such as polishing or coating to improve performance. Surprise, surprise, high performance inserts are more expensive than ordinary ones, and doubly so if they are guaranteed and traceable.

Buying inserts from a web auction site is a bit of a lottery. Fakes and manufacturing rejects turn up, and low specification inserts in high-specification packaging. And plenty of genuinely wonderful inserts available due to over stocking, bankruptcy sales, and production overruns etc. Buying second-hand is always a bit risky because no brand-name is immune to wear, tear and abuse. Buying on an auction site is a bit of a risk, and the brand-name doesn’t guarantee anything.

So I’m pretty much with NDIY, buying mid-range inserts from UK based hobby suppliers. I can’t say the branded ones work better than similar unbranded, though maybe they’re less brittle. Thing is my light hobby cutting of friendly materials doesn’t expose the shortcomings of low spec cutters. Yours might – what sort of work are you doing?

For me it boils down to:

• Fancy a gamble? Buy cheap from abroad. No tears please if they turn out to be manufacturing rejects! Some people do consistently well others come unstuck. Luck and risk.

• Require absolute certainty? Buy from a UK Industrial Supplier. No jibbing if the prices are agonisingly high – you wanted the best, suck it up!

• Ordinary hobbyist who wants reasonable reliability and understands tools don’t last forever? Hobby source in the UK.

Note I haven’t mentioned any brand-names! Let the supplier worry about that.

Dave

Edited By SillyOldDuffer on 26/02/2021 11:03:04

I think this thread is typical of a kind that are hopelessly frustrating for a beginner. Lots of people are happy to pitch in with common sense advice like "buy the best you can afford" or "I bought dozens for tuppence and they are great" but at the end the OP is none the wiser and is left to start randomly buying inserts till he or she gets lucky. Why is no one ever prepared to stick their neck out and say "I bought this specific insert from this supplier to cut this material on this lathe and it is excellent (or rubbish!)".

William.

You’re not wrong!

Don’t be fooled by those that eulogise over a paricular brand/supplier if there is any hint/evidence of a link between their review and the company supplying those wares (like serial reviews). They only get more freebies to review if they give glowing reviews on past items.

If you specify a non approved supplier like Banggood or a specific Chinese seller on Ebay or the item appears to be a knockoff etc the link will will be deleted by the mods to protect our sponsers. So it is usually a waste of time to specify a particular item. Most people buy the cheapest they can get so usually in a murky area. So the supplier needs to be either UK based or a known big name.

regards

Go on then, start the ball rolling.

Andrew

have you not read any of my posts?

Unfortunately I am neophyte, not a master. I can say that I recently bought some Korloy turning inserts and a Vardex thread tool holder & inserts from Cutwel following a phone conversation with a salesman there who seemed to know what he was talking about. I haven't used the turning inserts yet but have had good results with the threading tools.

William.

This where I buy my inserts from, https://www.shop-apt.co.uk and milling cutters for my cnc mill the quality and service is good. But they supply industry and a lot of inserts are only supplied in boxes of 10, some are available in model engineer quantities.

I also use Arceurotrade for inserts their own brand for me perform well for me.

I've gone as far as watching some of your movies! Love the Thompson engine.

I wonder if anyone has ever tried to make fair comparisons by use?

For a start, carbide inserts are designed with remarkably short lives in mind; but when used on the materials they are intended for and at their maximum machining rates.

A Sandvik catalogue I have quotes figures like 20 minutes - but this is for the professional production-planner and machine-setter equipping very rigid machines removing a lot of metal in very short times. The tip costs might be factored into the individual piece cost or spread among the overheads.

Really a fair comparison for any given tip between such industrial use and our use is how much metal it cuts to a good finish; but importantly, of similar metal and irrespective of speed.

There is a common belief that because the industrial user can work carbide tips at enormous speeds, usually under a much coolant / lubricant, these tips can only work at such speeds. I am sure some users obtain better results with higher surface speeds, but I would suggest it is very much more than mere speed, and have not noticed any loss in quality with using inserts at quite low speeds, especially on self-acting feed.

After all, brazed-on carbide tools with very simple tip geometry were being used industrially, on conventional lathes, decades before the advent of high-speed, NC-controlled machine-tools.

If I obtain a poor finish I first suspect a worn insert.

Then my setting and driving of the machine. Was the tip true to centre-height or a tiny fraction of a mm out? Did the work-piece chatter? Sometimes I have noticed chatter nodes depending on the length and diameter at the time, possibly too the material; and overcome by changing the speed - often downwards.

If I cannot see a fault there, I ask myself, is it the right tool for the material? As that Sandvik book shows, inserts are made for narrow ranges of materials under very particular production conditions.

If the tip I have used is blunt, I do not know if I have given it a good life and it has expired of old-age, or if I have blunted it by using it on its wrong material and/or inappropriate feeds and depths of cut (not surface speed).

'

The hobby's traders know our machine-tools, operating conditions and budgets may not match aerospace QA standards, and we don't usually machine exotic metals to microns anyway, so offer us sensible-quality inserts and some advice on the applications. I trust them. If nothing else it would be bad for them to sell us either poor-quality tools or top-rate ones far fewer of us could afford and too narrowly-specified anyway.

Now, I don't know about you but like many who at the exhibitions, I rarely buy complete packs of 10 tips at a time, at £4 - £5 a tip. This leaves the traders with assorted partially-empty boxes, so what they put in the box to hand to you may not be by the name on the box - not by deceit but by convenience, though possibly negating the trade-standard type-code also on the label. However, the names on my boxes of tips and the holders, almost all from one supplier at the shows, include Taegutec, Kenametal, Sandvik, Vandurit, Walter and APT. All probably selected by the retailer for general-purpose machining of common metals on ordinary machine-tools. I have noticed no special differences between any, but would I notice any such differences in my workshop, on my materials and fairly old, conventional machines operated by fairly old, conventional me? I have not investigated, but I very much doubt it.

To summarise:

Buying anything from on-line generalists will always be a gamble.

We can trust the retailers to the hobby.

We are using industrial-pattern tools often outside of the narrow conditions for which they are designed, so we cannot criticise them if they don't always work for us. That includes saying that because carbide inserts can work at very high speeds, such speeds are necessary; but the high-speed is intended to be accompanied by precise, consistent cutting rates and usually under coolant / lubricant floods.

These inserts from major manufacturers are also designed with quite specific lives cutting particular ranges of materials at a maximum designed rate.

How do we know if they have the same, longer, or shorter, lives in our hands? If shorter, why is it shorter?

And if the finish is not always a beautiful mirror... what is the real reason?

Try these people:

**LINK**

They seem to specialise in supplying the hobbyist, I've always had good quality and price from them and good service. If you ring up and talk to Jenny she can probably identify what you're looking for and what they can supply.