Indexable Carbide Inserts

[WannabewelderParticipant @wannabewelder]

Hi All

Help please. I'd like to purchase some basic inserts for the usual machining operations that you'd contemplate on a 9×20 lathe.

I propose making my own holder(s)

I don't want to have to purchase a host of different inserts for this operation or that operation; so what's the best general purpose insert to go for so that I can try them, mainly for facing and turning, and get a feel for whether they suit without having to spend a fortune.

Also I have a basic mill / drill on the way so, if the inserts could find an application in that too, it would be a bonus.

Regards

Wannabewelder

[WannabewelderParticipant @wannabewelder]

Best choice for general purpose machining

[Rufus RoughcutParticipant @rufusroughcut]

Hi Wannabewelder

Basic Tips something in this pattern is easy clamped at the end of a tool and size dependent will be fitted to some milling tools currently out there theres three tips/edges/faces to chew up on one tip so pretty economical, theres every manner of size discritiojn under the sun to contend with so you may need to think how big a tool you will make and size buy to suit your intentions.

Barry

[Thor 🇳🇴Participant @thor]

Hi Wannabewelder,

I have found triangular inserts can be used both on turning tools and milling tools. Steve Bedair has a description on how he made tool holders for 1/4" TCMT carbide inserts. I have made tool holders based on his description, and have used them for many years on my small lathe.

Regards

Thor

[Ian S CParticipant @iansc]

I made my tool holers from bits of car half shaft, and use the same 16 mm tips on both my vertical milling machine, and my lathe.

Ian S C

Edited By Ian S C on 18/04/2013 13:33:55

[WannabewelderParticipant @wannabewelder]

Hi guys and thanks for the swift response.

Rufus, you say "there's every manner of size and description under the sun" and that's the problem. What's a good "middle of the road" versatile form to start with?

Thor, I've come across the Steve Bedair site myself, and a very good site it is too! In fact it's what got me thinking about trying indexable tooling.

Ian, your tool holders are very similar to Steve Bedair's – his use a holed insert and, from memory, are a bit smaller but are very similar.

I've got a broken half shaft from the Land-Rover, so that's the holder material taken care of. It's just down to what's a good general purpose insert to start with.

Maybe I'll just go with what's in the Arc Eurotrade catalogue.

Regards

Wannabe

[Ian S CParticipant @iansc]

Heres the tool assembled. You can see the amount of wear on the front of the tool clamp, it looks as though its been attacked with a hacksaw. Ian S C.

[Chris ParsonsParticipant @chrisparsons64193]

Just bought some replacement tips for my Glanze tools from this supplier **LINK**

Most of my tools use these type of tips, although the ones I bought were for a parting tool (different)

I don't have any affiliation to the company but they seem to have a good range and have been recommended by others? (delivered pretty quickly too and were helpful when I called) They are in the UK, not sure where you are?

You can rotate the tips giving you two cutters for the one tip, and I find it useful when I chip one to be able to 'cannibalise' a tip from another tool temporariy

Regards

Chris

[Thor 🇳🇴Participant @thor]

Hi Wannabe,

the half shaft should be Ok for the holder. What kind/shape of insert depends on many things, among others what you prefer. I have used positive rake triangular inserts with three cutting edges. Other shapes may give you more(or less) cutting edges. For my small lathe I made holders that use TPMR110304 inserts. I also made a small single tooth cutter for my Mini Mill. For my new and bigger lathe I may have to make new tool holders that take larger inserts.

Thor

[WannabewelderParticipant @wannabewelder]

Hi guys and thanks for the additional info.

Ian, the assembled tool looks good. I'm optimistic that mine will be that good. Incidentally, I meant to say that the planned holder will be either 8 or 10 mm square.

Chris, I'm in the UK so your supplier would be good for me too. We have an engineers merchant in Norwich, which isn't too far so I might see what they can offer when I'm next in Norwich.

Thor, I decode TPMR110304 as:-

T= Triangular.

P= 11 deg. Clearance.

M= Tolerance as per table on all the insert dimensions. M is not the closest tolerance as far as I can see but certainly not the loosest either!

R= Chip-breaker one side.

11= Size, but I can't decode this.

03= Thickness 3.18mm.

04= Radius/Chamfer 0.4mm.

I've looked at Steve Bedair's site again but he doesn't specify an insert – just cheap from Ebay. From scaling the photos I reckon the insert is a bit under 3mm thick (and has a mounting hole) and the edges of the insert are approx.12mm.

I think I'll try the Norwich merchant as they seem to offer similar parts **LINK** and I'll also keep my eyes peeled on Ebay for a “bargain”

I'll report back when I've achieved something but I'm renowned for my slow rate of working!!

Meanwhile thanks again for the helpful comments and if you think of anything else please let me know.

Regards

Wannabe

[Thor 🇳🇴Participant @thor]

Hi Wannabe,

your decode is spot on, as far as I know the digits 11 is the length (in mm) of one side of the triangle.

Good luck with your toll holder production.

Thor

[Boiler BriParticipant @boilerbri]

Ian, I have often wondered about making my own, but have nerver vertured due to worry about the tip moveing, is this a problem?

I tend to use HSS and sharpen lots

Bri

[Thor 🇳🇴Participant @thor]

Hi Bri,

As Ian did, I milled a triangular pocket for the insert. The clamp and the cutting forces will push the insert into the pocket. I have never had an insert come loose.

If you look at Steve Bedair's site you will see that he uses triangular insert with a hole in the centre. He used an 4-40 Allen screw to clamp the insert to the holder. For the single cutting edge milling cutter I made I used similar inserts, and a countersunk M3 Allen screw to clamp the insert.

Thor

[Boiler BriParticipant @boilerbri]

I am going to have a go at that. I need a fly cutter for my sweetpea axleboxes. Hss end mills would damage too easily with the casting grit.
Cheers
Bri

[Ian S CParticipant @iansc]

My tool has a height of 15 mm. I have another one even more beat up, and it has a tool resess at each end, so it can be used left hand, and right hand.   Ian S C

Edited By Ian S C on 21/04/2013 12:59:34

[John McNamaraParticipant @johnmcnamara74883]

Hi Wannabewelder

If you happen to live in an area where there is a decent trash and treasure market. Or possibly second hand industrial machinery suppliers, It may be worth keeping an eye out for 25mm or one inch square square shank lathe tool holders. A fairly standard size for larger lathes. Ebay maybe but beware of Chinese look alike tools.

The tool tip height will be too high for your lathe but it is fairly easy to cut them down (from the underside, and the back edge if need be) to bring the tool tip to your centre height, You can also shorten them if need be to fit your tool post. You could put them in the four jaw or on the mill if you have one. The shanks are not hardened, although they are a better grade of tool steel. You will need to leave maybe 20 or 25mm near the tip unchanged to enable the clamping system to work.

Traders normally have quite a few and you should be able to negotiate a fair deal.

Make sure you pick holders that take standard square, triangle and Diamond tips. Both with or without a hole. With a hole means they are clamped from above and on a post. Better for heavy cutting.

Often I see packets of new tips usually from top end suppliers, but beware of buying unknown grades. Well unless they are cheap!! And make sure they fit your holders.

Cheers

John

 

Edited By John McNamara on 21/04/2013 14:03:01

[WannabewelderParticipant @wannabewelder]

Thanks again for all the advice and encouragement.

I happened to be browsing through the digital issues on the website yesterday evening and I came across an excellent series of articles by Mike Haughton – If you're on the forum Mike, congratulations they're very good and I'm glad I found them before spending money.

They're in MEW March to June 2008 (Editions 136 to 139) and, in my opinion are well worth a read!

Regards

Wannabe

[Roger HulettParticipant @rogerhulett83124]

Taking this discussion (although somewhat dated) a stage further.I have bought a set of 5 Utility Indexable toolholders. STNCR & STACR STDCR & STECN and STCCR

The "S" and the "T" are self explanatory,however for example two of the toolholders have only one difference in the number…..stAcr (0degrees) and stNcr. (3degrees) The difference being the side cutting angle.

My question is whenand why would you use "A"…..0degrees or "N"….3degrees

Thankyou.

[Nigel McBurney 1Participant @nigelmcburney1]

I was given a quantity of of identical inserts,without the holder,so I took a tip with me when I went round the auto jumble at various events ,soon got a holder for a couple of quid, I have made my own holders,these were made to take inserts which have holes in them ,so they can be secured to the holder with socket screws.

[JasonBModerator @jasonb]

Posted by Chris Parsons on 19/04/2013 09:24:12:

Just bought some replacement tips for my Glanze tools from this supplier **LINK**

You can rotate the tips giving you two cutters for the one tip, and I find it useful when I chip one to be able to 'cannibalise' a tip from another tool temporariy

Regards

Chris

With a second holder you can use the other two corners as well so get 4 usable corners from one tip, the obtuse ones are good for roughing out or interupted cuts as they are a bit more robust. I have also made some large boring bar holders for these tips which are quite easy to make.

[Ian S CParticipant @iansc]

After you have chipped the tool, get a suitable sized 8.8 (or better) bolt, and grind it up for a boring bar, and braze the old carbide tip on, green grit wheel is ok for shaping the tip, and a diamond lap for sharpening.

Ian S C

[AjohnwParticipant @ajohnw51620]

I stick to these as they are the nearest thing to a sharp indexable tip that I am aware of

That's an 11mm tip fitted to what may be a 9mm tip holder. The 11's seem to be a bit short of that and the 9 a little bigger. 16mm is also available.

This is the same general shape I usually use on HSS because it will turn both ways even though there is negative rake in one direction and it will face and face plus relieve shoulders as well. The rake is positive in both directions on the tips. The only problem is this style of holder which only seem to be available in cheap kits with several shapes in them so at some point I need to make one myself. The tips in these kits aren't bad. They look like general purpose to me but don't have this degree of rake. Some of the kits use hex socket screws to hold the tip – best change them to torx before the keys wear out.

Boring bars are also available that take the same inserts. Only problem with the one I bought is that the picture showed a tip angle suitable for boring blind holes and lightly facing the end. It turned out to be angled for through holes so when needed I will have to modify it. Thanks RGD.

If people are into different profiles for different materials they are pretty economic. 2 will do. One micro polished for aluminium and none ferrous and another for harder stuff, stainless etc. The reference numbers for them can be found on APT Carbide but there is need to look at the actual page for a tip to see what it's suitable for. The one in the shot is for stainless and alloy steels and also works well on brass. The aluminium tips might be better. I didn't have any last time I worked on brass.

To be honest though I am not convinced that they are any better than a highly polished decent grade of HSS. The problem with HSS is getting the polish and also the small rad. A slip stone helps a lot and can also be used to sharpen the tool while it's on the lathe.

John

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