Best carbide insert shape/type?

[Member 66061]

I would like some info on what the best shape/type of carbide insert for lathe tools are for general left/right hand lathe cutting. I dont understand why theres so many different shapes.
Theres TCMT and theres DCMT07 inserts, and other shapes. So what dictates the choice of insert used?
I would have thought TCMT would be best? Thanks

 

[ukracer]

I would like some info on what the best shape/type of carbide insert for lathe tools are for general left/right hand lathe cutting. I dont understand why theres so many different shapes.
Theres TCMT and theres DCMT07 inserts, and other shapes. So what dictates the choice of insert used?
I would have thought TCMT would be best? Thanks

Adam has done a few videos lately explaining the nomenclature (posh word for figures used to describe tips and tool holders) of various tools and inserts.

 

[dobbslc]

I've had the same thing recently, I had the wrong inserts on the wrong tool.
A right hand tool if you're looking at it in the tool post pointing at the work it points to the left! Don't ask me why though. Left hand tool points right..
You need to know what lathe tool you have first as they are different. The seats are different as far as I can tell, I didn't known what my cheap looking tools were so bought a Sandvik one and now I know I need TCMT tools to fit it thanks to other members here.

I got this link in my post about it.
http://www.carbidedepot.com/formulas-insert-d.htm

 

[Member 66061]

There is no such thing as general lathe cutting

Type of material, surface speed attainable with your machine, feed rate, depth of cut, rigidity and a fair few other factors come into play when deciding which is the 'best' insert - that's why there are so many.

28 seconds into that very informative vid, he says he uses these tips for general turning and facing and whatnot
I had a bad day and just gave up on those crap tool holders i have. The DCMT boring bar is still good though.
So what would be the coding for a CCMT type insert 3/8" size? if such an insert exists? If not what would be the next type choice?
It made sense what he said about using those rhombic inserts odd corners for interrupted cuts.

 

[ukracer]

28 seconds into that very informative vid, he says he uses these tips for general turning and facing and whatnot
I had a bad day and just gave up on those crap tool holders i have. The DCMT boring bar is still good though.
So what would be the coding for a CCMT type insert 3/8" size? if such an insert exists? If not what would be the next type choice?
It made sense what he said about using those rhombic inserts odd corners for interrupted cuts.

He has more videos that show the black book with all the information you need. I guess that information will be available on the tool/tip suppliers websites when you know how to read it

 

[Member 66061]

He has more videos that show the black book with all the information you need. I guess that information will be available on the tool/tip suppliers websites when you know how to read it

Ive only used brazed tip and HSS tools before, so this insert thing is very new to me. Thanks for your help, i enjoy learning things.
What do you think of these? http://www.ebay.co.uk/itm/NEW-7PCS-...215648?hash=item4b0e1b4620:g:CAcAAOSwnFZXUn1M they should be a 12mm shank
I am skint, but the lathe is useless without tools.

 

[Imakora]

I'd be willing to bet that what he considers general isn't what the next person considers general.

General on the type of machine I trained on would rip something like a myford to shreds in seconds (considering I could have stuck an ml7 in the chuck and parted it off).

General on my current lathe would be 'sneaking up' on that type of machine.

But hey, what do I know?

Good Edit.

 

[Member 66061]

Well i guess theres only room for professionals in this forum. Youll forgive a squid like me for not having much to join in with the willy waggling contest.
This sometimes feels like a fine art exhibition and im there with my potato prints.
Good edit.

 

[brightspark]

Ive only used brazed tip and HSS tools before, so this insert thing is very new to me. Thanks for your help, i enjoy learning things.
What do you think of these? http://www.ebay.co.uk/itm/NEW-7PCS-...215648?hash=item4b0e1b4620:g:CAcAAOSwnFZXUn1M they should be a 12mm shank
I am skint, but the lathe is useless without tools.

I 99percent use hss tipped tools on most materials and have done for 45 years. just learn how to sharpen them properly .most new folk are convinced they need carbide insert tip tools

 

[Imakora]

As a complete novice, I benefit greatly from the knowledge and skills that folk share on this forum. Threads like this are a great source of info and certainly help guide people like myself in the right direction. Keep the info coming all.

 

[ukracer]

 

[T0rnado69]

What do you think of these? http://www.ebay.co.uk/itm/NEW-7PCS-...215648?hash=item4b0e1b4620:g:CAcAAOSwnFZXUn1M they should be a 12mm shank
I am skint, but the lathe is useless without tools.

item location......... india...

i would try get some from the uk... incase you get something delivered that's faulty or damaged.

 

[Member 66061]

As a complete novice, I benefit greatly from the knowledge and skills that folk share on this forum. Threads like this are a great source of info and certainly help guide people like myself in the right direction. Keep the info coming all.

To be honest, it seems im here to show myself up and end up with my head in my hands.
Someones got to be asking the questions for threads like this to provide the info for novices.

 

[WorkshopChris]

Its not just the insert and the holder and matching them to the material.
Its also finding something that will work with the lathe you have as PDG said one mans general is the next mans heavy.
Abom79 will often take off 1/4" in one pass on a roughing cut when getting stock down to size, but on a myford or similar that is many passes and 5 min's work maybe.
For light cuts sometimes you cant beat the finish from a HSS tool. And on a similar feed a tipped tool will just rub and overheat.

 

[Hood]

What size of lathe do you have? What materials do you cut?
Regarding the tools you linked to, well I wouldn't even think about them but others may disagree.
I would much rather go with a decent small lathe tool such as Glanze, bit more expensive but made more like the real ones.

 

[T0rnado69]

To be honest, it seems im here to show myself up and end up with my head in my hands.
Someone's got to be asking the questions for threads like this to provide the info for novices.

not at all.... im fairly new to carbide tip tooling too, i started of using brazed tip tools.

but found after a while the cost and time involved in getting them sharpened.

but being able to replace the tip on the tool yourself.
even half way through a job if need be, it only takes a min.
where my local sharpening place was on a week turn around.

i went for the biggest holder my tool post would take. 16mm.
and slowly added more holders to my collection when they come up for sale.

 

[brightspark]

[QUOTE="
but being able to replace the tip on the tool yourself.
even half way through a job if need be, it only takes a min.
where my local sharpening place was on a week turn around.

.[/QUOTE]pay to have your lathe tools sharpened

 

[Member 66061]

I have a Clarke CL250M, my granda died and my uncle passed it on to me.
It is a small crappy lathe, but i have done some good work on it >click for link< and saved some money.
I put any metal that will fit in it and turn it, i was doing some EN8 today, i know, horrible to machine, but its what i had.
I got some tools with it, but im starting to run out after damaging them, the lathe would be an ornament with no cutting tools.
I have a quick change tool post on it now and it will hold 12mm max

I used to have access to a big lathe and had set up a bench grinder to sharpen HSS tool steel with, but bad things happened and all that is gone.
I learned how to sharpen cutting tools from HSS blanks.I dont have a suitable grinder to make HSS tools now and im not going to get one.
I just see the same results from the carbide tips as the HSS and thought indexable would be a fuss free way to go.

That kit from India is what im after, but minus the boring bar. I will try to find something similar from the UK that wont cost too much.

 

[Hood]

EN8 machines lovely but if your tools are crap the results will be too.
Ok so it is a small low powered lathe so I would say go for a positive insert tool. A good all rounder would likely be one that takes a CCMT insert so something like SCLCR on this page
http://www.glanze.co.uk/acatalog/Single_Turning_Tools.html
Another tool worth looking at would be one that takes a DCMT as it will allow a bit of profile cutting as well as straight turning and light facing, so again on the above linked page scroll down to the SDJCR.
I would say a 0.4mm nose rad would probably be best suited to your lathe.

On my manual lathe (Colchester Triumph POS) I tend to reach for a PCLNR which takes a CNMG insert but it is a negative insert so is really suited to a more powerful and robust lathe than you have. On my CNC my go to general tool is a SDJNL (DNMG 15 06 insert), very strong tool and much more versatile than the CNMG insert. Again though a negative insert so suited for medium to large lathes.

 

[Member 66061]

EN8 machines lovely but if your tools are crap the results will be too.
Ok so it is a small low powered lathe so I would say go for a positive insert tool. A good all rounder would likely be one that takes a CCMT insert so something like SCLCR on this page
http://www.glanze.co.uk/acatalog/Single_Turning_Tools.html
Another tool worth looking at would be one that takes a DCMT as it will allow a bit of profile cutting as well as straight turning and light facing, so again on the above linked page scroll down to the SDJCR.
I would say a 0.4mm nose rad would probably be best suited to your lathe.

On my manual lathe (Colchester Triumph POS) I tend to reach for a PCLNR which takes a CNMG insert but it is a negative insert so is really suited to a more powerful and robust lathe than you have. On my CNC my go to general tool is a SDJNL (DNMG 15 06 insert), very strong tool and much more versatile than the CNMG insert. Again though a negative insert so suited for medium to large lathes.

This is really helpful, thankyou.
Looks like i will be placing some orders on that site then
SCKCR0808D06 and SCLCR0808D06