Tool post height

Thread has also moved on to people saying that a QCTP lacks rigidity, plus the fact I had already done that video several years ago.

But as I said in that post 6mm and 8mm holders are also readily available so the OP does not really need to limit himself to 12mm which becomes a lot less "desirable" when it needs one of several solutions to make it work on a machine designed for smaller shank tooling.

But here you go. First we have a 8 x 8 shank tool ( JBTools) which is my usual "rougher" as it makes use of the two obtuse corners of CCMY & CCGT inserts. The Insert is a CCGT 060402 I think from Kennametal and classed as "Light Finishing" though it may have been from APT, once the two main corners are used I don't keep track of them. Cut was only 0.225" ( 5.7mm) as the length of edge is not enough to do 1/4" bar 1" EN1A. Note that I'm running 2.5 times faster with the Carbide as with the HSS and less noise from lathe belt .

No, but is was originally about insert tooling.

To answer the other questions raised. The Video I posted Yesterday was showing a 6mm square HSS cutting tool that had been freehand ground, no special jigs, grinders or honing of the edge. Rod's video is also HSS.

The sharper **GT inserts in this mornings videos do allow for a finer cut but as you say can be a bit more delicate, I would generally not use them for such heavy cuts but that is what was in the holders. They were also used inserts not new for the video. I'll also add that I usually don't take off such a heavy cut at such slow speeds my reasons why have been covered elsewhere on the forum several times and you should build upto what works on your machine don't try such a cut straight away..

Yes there are many factors that go into trying to achieve the perfect finish/removal rate/tool life.

No CNC does not work it out for you, it's up to the person programming the machine to select tool, enter feeds, speeds and cutting parameters. There are some wizards that will give you some of the se figures but the results should be used as a guide as the individual machine will dictate what it can actually do. Also buying tooling from reputable suppliers who will often give some cutting data for their tools or have makers catalogues available to download will also guide you to what a particular tool is best run at in a particular material.

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Did you read the subject line, Vic ?

The material from which the insert is made is irrelevant to that.

MichaelG.

Yes could just have well needed to grind 3mm off the top cutting face of a 12mm HSS toolbit as drop an insert 3mm into it's holder. My point was why but the bigger one when smaller does the job without modification.

Edited By JasonB on 11/07/2021 10:35:55

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The principles would equally apply to Warner’s HSS inserts : **LINK**

https://www.arwarnerco.com/CCMW-2-1-5-5-p/inserts-ccmw-21505.htm

Or even to these : https://contour-diamonds.com/

MichaelG.

Edited By Michael Gilligan on 11/07/2021 13:58:31

Well thnx 10^6 JB that is most informative with proper explanation that I can work with and learn from

I will certainly follow through

and not go rushing down the 12mm holder route just yet

Its clear that going carbide is something of a black art - hss is so much simpler by comparison

As a matter of interest have disposable hss tips every been marketed or is that a silly idea?

Well blow me if this didnt answer the question i just asked HSS inserts?

bit pricy for disposable - presumably one could gear up to having a jig to fit to a bench grinder where a touch would be just enough to put the edge back on

Perhaps MOD we should make this a separate topic?

There are a couple of users of the Warner inserts on another forum I use, they give them a lick with a diamond slip to give them another lease of life.

They are not priced much different to brand name carbide inserts and their cutoff inserts which would fit my Mini-thin holder are less than the carbide ones for that.

Well that came to a dead stop Warner are available here and their product $8-12 are not cheap, in fact it brought me back to hss form tools

I can get a set of 10mm 8pce Soba £49 from Chronos and to my simple mind it looks like these can be sharpened with a light touch on the end.

It brings me to the question of tool sharpeners jigs (like twists drills - many are mickey mouse)

then I came across this from one of your sponsors

https://www.youtube.com/watch?v=bzEQCvE1cIk

https://www.eccentricengineering.com.au/uk-distributor

£190 not cheap

Anyone any experience here, suggestions

Have you thought of trying a Tangential tool, bought or home made? Quite a few folks on here like them including myself. Easy to sharpen and built in height adjustment.

Tangential Tool

Wow that is rude, its like you know what the other way round

will look into but the tool holder and sharpener jig for LH and RH are £130!!!!! 5/16 - 1/2"

So buy the RH and copy its geometry to make you own LH.

Or follow some of the other advice and make all of them; that's about £5 of material and a productive evening in the workshop. My RH tool is made from a short piece of10x20 steel bar, and the sharpening jig is a scrap piece of aluminium and two M5 bolts. All for a 3mm square toolbit. I've been meaning to make a LH one since I finished it. That was over 15 years ago which shows how often I need a LH tool. I generally use carbide inserts on 8mm shanks in Dickson QCTP holders that I bought for the mini-lathe I had at the time. Neither are the limitation for the WM250 I now have...

As said, Tangential tool holders aren’t difficult to make. I used 12° on both angles and it works fine.

Well ive been doing it from the front lifelong, Ive got enough trouble with Mrs Myford and Mistress doreen Im not going to start round the other way Ive got enough trouble getting them into shape as it is

Making a Tangential Turning Tool is simple. Three milling operations (Possibly a fourth ) and one drilled hole, once the material is cut to length.

I have them in 1/8, 1/4, and 5/16.

A friend made his in both RH and LH forms.

The sharpening jig is simple and the toolbit is adjusted to to bring the cutting edge to centre height.

There have been two articles on making such a tool in M E W

Easy to make, sharpen, and effective in operation, whats not tom like?

Howard.

Edited By Howard Lewis on 12/07/2021 08:09:24

If you make one with a separate clamp for the toolbit, you could make a perfectly adequate holder with a hacksaw and files.

And cheap to “run” using small pieces of HSS.

Hi Guys,

I agree with the comments that Tangential lathe tools are quite easy to male and use. I made one quite a while ago.

Easy to set up and easy to sharpen. You get a good finish too.

This is a drawing of one that I made. Just scale to suit whatever HSS or carbide you want to use.

As you can see the finish is not too bad.

Certainly better than my photography

That is not unlike one that I made to cut a semi circular thread with a 4 mm pitch!

A good variation on the theme!

Howard