lathe tools

I have a ml7 lathe and am about to buy a set of lathe tools and was wondering what view others have regarding the best type, HSS or
Indexables
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Me too! I have a Colchester Bantam and would like to buy some TCT holders and bits.
I've seen the "Glanze" tools sold by Chronos:
http://www.chronos.ltd.uk/acatalog/copy_of_Special_Offers_on_Glanze_Tools__.html
and wondered if these were any good. Opinions anyone?
Apologies for hi-jacking your thread, but which inserts would you need for free-cutting stainless and aluminium?
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bert wrote:

Don't throw your money away on pre-ground tools.
HSS definately. Get five or six 1/4" square HSS bits, and the same number of 3/16" HSS bits. Maybe Two or three 3/8" bits. They make good shims to raise up the others upon, to get them to center height, if you are using the Myford clamp type tool holder.
The 1/4" and 3/8" tools are slow to grind, but easy to see when so doing. TH esmaller bits are cheaper, and take far less time to grind, but are harder to see when grinding, so you have to have at least an idea of what you are trying to achieve. The small bits are plenty strong enough to do honest work on a Myford sized lathe.
Those will last you a VERY long time.
Get a decent small bench grinder, and learn to grind your own tools from scratch.
If you buy the pre-ground HSS tooling, you will have to learn how to grind them soon enough, and if you buy indexable, like as not, you will become annoyed with metalworking altogether, before you reach the point where the inserts start lasting long enough to seem worth the price.
Buy or download a copy of the South Bend Lathe book, How to Run a Lathe. It has some worthwhile info on tool shapes. Watch the angles, though. Try to avoid getting caught out, and grinding a tool that is supposed to be held in an upwards angles tool holder, if you do not have them (typically, like the ones made by Armstrong, they have a 15 degree upwards angle).
Cheers Trevor Jones
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HSS everytime. Indexables will not make you a better turner and will cost you alot of money. Get HSS and the grinding is easy. Everytime you just lick the tool up on the grinder you save money. Been a turner all my life and made good money, now just a model engineer and only one indexable in the shed that someone gave me and I never use it. I wish I could meet the members of the group and within a few hours show them how to grind tools.

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bert wrote:

Depends mostly what you are working on. If it's mild steel, brass/bronze and ally then HSS is best for the hand lathe.
For stainless cobalt-HSS or carbide is a help, and for anything harder than stainless carbide (or even diamond, ceramic or CBN) is necessary.
HSS is sharper (when freshly sharpened) and much tougher than carbide - carbide is harder, but it is far more brittle. Carbide also works longer, harder and better at high temperature, but this doesn't matter much in hobby work - the brittleness of carbide is far more relevant.
I'd start with some HSS (or cobalt-HSS) blank square bars and a cheap grinder. Should cost about 30 in all, about the price of a single good indexable tool plus a few inserts. If you can get someone to show you how to grind HSS tools that's a big plus, but it isn't that hard to learn. You can then make almost any lathe tool you want, but some like parting tools and boring bars are better bought.
Many people like indexable carbide parting tools, even for softer metals, and there is some merit in this, perhaps because the cutting end is wider than the blade of the tool.
However after a bit of experiment and practice I'm getting good results with a HSS blade-type parting tool - sharpen frequently, mount rigidly so it's central on the crossslide and absolutely at right angles to the lathe bed, and lock the carriage and top slide.
The only time I use brazed carbide is for small boring bars. Regard them as disposable, but they aren't very expensive. Good for getting into smaller holes, as indexable boring bars need a large hole, and grinding boring bars from HSS blanks is very tiresome.
You might want to buy a cheap set of brazed carbide tools as an introduction to the brittleness of carbide - otherwise no. Another cheap-ish introduction to carbide is the TPUN RH tool available on ebay from marypoppinsbag - but throw away the horrible screw, make a suitable thick washer and use a proper M5 allen bolt instead.
But start with HSS, not carbide.
-- Peter Fairbrother
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A beginners thoughts:
Most here seem to say buy blanks and grind your own.
But, if you are a beginner isn't that just adding something else to learn and worry about? Is it not better for a beginner who already has a lathe to buy some ready to use tools so that they can get the hand of using the lathe first? Then later on learn to grind their own tools?
I mean, if you screw up the grinding you're never going to begin turning, right? Or the turning could be terrible with a rubbish home brew tool. You get down and potentially give up.
When I got my ML7, also got 1 tool, clearly ground by the previous owner. It worked ok, but I went out and got a set of cheapo tools to get the hang of the lathe. Then I started grinding up the cheapo tools to get the hang of grinding. Then lastly I bought some good blanks and now make my tools.
Its all very well old timers saying home brew is best, but for a beginner, that to me seems like a route to possibly not ever getting going. Or a recipe for added problems.
Beginners, and I still consider my self a beginner after 2 years of owning my ML7, need it simple.
So I say get some cheapish ready made tools, get the hang of the lathe, find the limitations, and then look at grinding your own tools a little later on ( or in parallel to learing about turning. That way you get to play at lathing immediately, with out the added pressure of grinding tools.
AC
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AC wrote:

If you are a beginner, begin by learning how to grind tools. It is part of learning how the lathe cuts, and why it won't, at times.
If you never understand the basics of the physyics of cutting metal, you will never understand why you are not getting the results you wish to, or understand what has gone wrong (or right) with your set-up.

An eight year old can learn to grind a decent tool. It is an elementary level skill. All new skills come with a learning period. Best to get it over and done!

Pity! You were stuck using one tool, and had no other options. Had you learned to grind your tools early on, you would have had ALL options open to you right away.

Gawd! You make it sound like getting three angles ground so they meet at a sharp edge, is some kind of bloody great miracle! It isn't!

If you had started out learning to grind a tool for yourself, right off, you would be a lot further along. You would not have run into whatever stunbling blocks that have held you back, and you would have a far greater skillset in hand, IMO.

Grinding tools is not pressure. It is a basic skill, that should require about as much concentration as learning to tie ones shoelaces. If you are getting scared by it, you are spending too much time considering the problems, and not enough time grinding tool blanks.
Really!
Easy!
Not Magic!
Not to be feared!
But if you never try it, you will never learn it!
Once you have this skill, all options are open.
Cheers Trevor Jones
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I was when I did and I agree whole heartedly with the overall tone of this thread. In general get HSS blanks and grind your own. I have a few indexables I keep for nasty jobs like stainless and getting below the skin on burned & rusty brake disks, but for 95% of normal daily use you can't wear out HSS fast enough to worry about - not playing about in your own shed, production work is a different kettle of fish altogether.
Richard
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from Richard

I was fortunate enough the get an apprenticeship with Coventry Gauge & Tool where preparing tools for lathe work came second only to general 'fitting' work.
Although I didn't touch a lathe between 1962 and 2005 I still retain all the skills I gained during the apprenticeship and sharpen all my tools by hand on a bench grinder - I really do mean _all_ my tools - today I converted a broken 1.4mm carbide drill to an end mill and made a 0.3mm wide carbide parting off tool from another damaged 0.5mm drill. 95% of my lathe tooling is HSS but I do have a few indexable carbide tips that I use as if they were HSS (as far as reginding/sharpening is concerned) these are used on 'difficult' materials such as Stainless Steel, Spring Steel and Cast Iron.
For me, each tool material has its particular merit and knowing which to use and when is the skill. Buying pre-ground tooling might be alright - and even necessary - in a producion environment but for 'hobby/home workshop' use it is imperative to cultivate the skills needed to keep all tools sharp - a blunt tool is a liability!
JG
JG
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They're also handy for sharpening drills and centre punches and taking the burrs off cold chisels and generally removing relatively small quantities of hard-ish material. Many of the typical small trade books like Zeus and the Dormer Drill book that turn up a boot sales etc for a quid or two have diagrams of what you're aiming for in terms of tool shape. Hand sharpening drills can be a bit tricky, especially in small sizes, but again it's a skill well worth learning even if only to recover broken ones to start with.
Richard
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On or around Fri, 23 May 2008 13:01:25 GMT, Trevor Jones

anyone care to point to a decent place to get tips on this, ideally online? Or if there isn't such an online resource, does anyone fancy having a go at producing one? While I mostly make tools that work, it sometimes takes more than one "go" and I daresay mine could be better if I knew a bit more about it - I expect most of us end up with a tool that does the job adequately rather than well, quite often.
I have one indexed tool, for general turning and one indexed boring bar. I like the carbide tool for the fact that it stays sharp, it's difficult to bugger up by cutting too fast or inadequate coolant, and it's dead quick and easy to get a really sharp edge, you just change the insert, or turn it round to get a new cutting edge.
Downsides, as others have said: it's an expensive way of doing it: a single half-inch square HSS tool will last for ages, and costs little (although, to be complete, you should factor the grinding wheels and the electricity the grinder uses into the cost).
Carbide tips also last quite a while but they're difficult to say the least to sharpen credibly, they break if you're careless and they cost quite a lot to replace. The general turning tool I use has a CCMT09 insert and they cost several pounds each for decent ones, as much as a whole half-inch HSS tool, which will last much longer unless you do something really stupid with it.
Now, I've just given the impression that I only use 2 tools, both indexed. That's not really true. Okay, a lot of the time I do use just the one tool, but then a lot of the time that's a good tool for the job. In fact, if you come and look at my lathe, chances are the normal indexed 75 tool is on one side of the toolpost and the parting-off tool is on the opposite side. But that just reflects that these are the tools I use most often.
I have quite a few other HSS tools, some of which came with the previous lathe, and some of which I bought. I also have a parting tool with an HSS blade. I use the HSS tools primarily for anything that needs a non-standard shape or angle. The most recent one was a funny pointy tool to turn the reverse chamfer I mentioned in the post about the pipe bulging tool I made. This requires an odd set of angles on the tool which you'd not get on an indexed tool anyway - technically, it could be done with triangular insert but the small diameter would mean there wouldn't be enough clearance below the cutting face. On the HSS tool, that just meant a bit more grinding.
Other things I've got HSS tools for are machining circlip grooves (a very very thin cutting edge, only cuts about 1mm deep and on the end of a 1/2" tool - took a bit of grinding, that one, but invaluable once done, also tools with large radii on the end, tools that leftwards instead of right-wards, one that cuts a semicircular 2mm groove, and so on. All of these had a special use at the time, and some are still in use. Or they get re-ground to a different shape for the next special job. For this sort of turning, you can't beat HSS unless the material to be worked is simply too hard.
--
Austin Shackles. www.ddol-las.net my opinions are just that
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Austin Shackles wrote:

Take a look at the Sherline website. www.sherline.com IIRC.
Several hundred pages, mostly devoted to very small lathe and milling machine work.
There are a couple pages of info on tool grinding there, that are worth a look.
If you are not on a dial-up account, search around and find a copy of the South Bend Lathe book, How to Run a Lathe. Tool shapes are covered there pretty well.
A copy of this book in hard copy form, can usually be found for under $20 on this side of the ocean (Lee Valley Tools sels a older version for $10) and I am pretty certain it is available from the booksellers in the UK. Same book, is the Boxford manual, titled, IIRC, Know your Lathe.
I usually steer beginners towards 3 UK published books to start off.
The two Tee Publications books (or whomever has taken over that line) Workholding in the Lathe, and Milling operations in the Lathe, by Tubal Cain, and The Amateur's Lathe by Sparey. Between them, they cover a LOT of ground, and show that many things are possible with limited tooling.
Cheers Trevor Jones
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I agree with the sherline pages, I learnt to grind tools following this: http://www.sherline.com/grinding.htm One thing I disagree with however is the recommendation to have a cup of water to dip the blank in if it gets to hot (pretty sure it was this article). Dipping hot HSS into water can cause micro cracking of the steel. The water cooling is a throwback to Carbon steel tools HSS should be ground hard and quickly, faffing about taking light passes wastes time, and heats the blank excessively. My top tip: clamp the tool blank in a pair of mole grips and have at it, you wont burn your hands, and its virtually impossible to draw the temper on a good HSS blank. grind it hard and fast to approximatly the correct shape and then tune it up on the other wheel, and finally (if you need a good finish) a diamond 'stone' Dont worry to much about the angles, they are to aim for, not gospel. The correct shape is one where the first and only bit that contacts is the cutting edge.
Dave
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dave sanderson wrote:

I show the guys the mole grip/ vice-grip technique.
From what I read, the microfracturing of the surface tends to come about from dropping the red hot tool bit into the water. I tell folks to consider that HSS will hold a cutting edge at red heat, and that for the most part, they cannot hurt the tool blank enough to affect the way it cuts, by anything they do with a grinding wheel.
A dip tank is nice, for when you have ground away the most of the tool, and you have to get down to the fine bits of work, and you want to be able to hold the tool bit by hand.
It's amazing, how heavy those little bits can be, when they have been in contact with the wheel for a few seconds! :-)
Cheers Trevor Jones
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If I need to hold onto it I often use a welding glove, first time I ground a tool bit I put it down and then picked up the wrong end... Owowowowow...
Dave
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See we are back were we started, not quite, We had people saying that they could not grind HSS tools yet know they are grinding tips. I give up on this one.
enlightened us thusly:

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enlightened us thusly:

If you grind the tool wrong, it will do one of 2 things, either not cut at all, or snag in the work and break something.
Or it may cut poorly, leaving a poor finish and generating much heat, resulting in going blunt quickly.

Oh fer fexache, get off your high horse.
Even if it did come over a bit patronising, he's right.
No-one said you can't buy tools, most of us do. But you also do need to learn how to make them, if you're going to do anything more adventurous than straight turning or facing or boring.
as for patronising: it's like offending people. You can only take offence, you can't give it. I could be as offensive as I like, but if you decline to be offended, then I'm wasting my time.
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Austin Shackles wrote:

That pretty much covers it, really!
Cheers Trevor Jones
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That's all very well, but I personally agree with AC. If you're a newbie who has just bought their first lathe, then the last thing you probably want to worry about is learning to grind tools from scratch. You want to stick some metal in the lathe, and make chips. A set of preground tools will let you do that. Once those pre-ground tools aren't cutting how they should, then they can start to learn how to sharpen them, and how cutting angles work.

And your way is like telling somebody that if they want (fill in the blank) cuisine, to cook it before they've even tasted it. Most people will of tried what they want to cook before they try cooking it, or at least have a rough idea of how it will taste.

True, but there's more than one route to acheive most things.
<big snip>
My first set of cutting tools were pre-ground. They let me try out the lathe, and then once they started to get blunt, I started to re-sharpen them. After that I started to learn about cutting angles, before moving onto grinding from blanks. However, I now mostly use indexable tooling for easiness, but still use the odd HSS tool mainly for profiles and flycutters.
I would personally recommend that any person new to the hobby, who hasn't got anybody to guide/help them nearby, that they buy some pre-ground tools. It might not be the ideal way, but it allows them to make some chips, and provides them with a rough idea of how tools should be ground. From there, they can go on to learning to grind them.
moray
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moray wrote:

Except if you were to follow his plan, you would have bought pre-ground tools, but not a grinder, because grinding tools is hard.

Point taken. Bad example, but the best I could come up with in short order.

Yup. True.

Can you still buy a set of pre-ground tool that is not total shite out your way?
Not here.
Chinese, round edges, burrs, and no points, made of mystery metal, are the best I have seen. For the most part, I would not spend the few dollars asked for such garbage. I would never recommend them to anyone, let alone a new user, that may or may not be able to recognise why they would not work out of the box.
And the occasional Myford set that sells for insane prices, for no reason that I can come up with. Them on Ebay, too. Not that they are exactly a bargain from Myford...
Better off making your own out of old files, if you can find one that is actually all high carbon steel, rather than just case hardened. Even if it does mean learning to heat treat them along the way too.
My recomendation is still to learn to grind a tool right, right off. Grinding a tool poorly, right off, is at the least, a step towards the knowledge that will be with you for a long time!
I figure if a new owner is so lacking in skills or experience that grinding a tool is going to be a scary thing, then that same person is going to be pretty hard done by, when the chips start coming off hot and everywhere!
Unlike AC, who was preaching that it was hard to do, and to be avoided, I am saying that it is merely another skill to learn, that looks daunting, until you get your hands onto it. It's really not such a fearsome thing, to grind a decent working lathe tool, and it should not be approached with the amount of fear that is evident from some of the posts I have seen along the way.
Cheers Trevor Jones
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