Holders to use the obtuse corners of C* inserts.

I have quite a few CCMT/CCGT inserts which are worn or chipped on the 80 degree corners but pristine on the 100 degree. I can't find holders to use the 100 degree corners though - probably not using the right search terms. They must exist!

Can anyone advise?

Robin.

I have seen them but only on DIY forums. You may have to make your own.

Paul

Hi,

Here is a link to APT Link

If you google the tool code (SCBCRxxxx) you may find them on eBay.

David.

Edited By David Colwill on 29/04/2021 05:54:49

UK made and cheap..

JB Tools

You can also get SClCL which is the left hand one for facing, I got both L & R from JB Tools.

Edited By JasonB on 29/04/2021 06:55:32

I have one from JB tools l can turn and face with same tool holder.

https://youtu.be/vzrhyDr4JBM

David

Back in the day we campaigned 80 degree rhombic turning tools using 12 16 & 19mm tips, we also had holders to use up the obtuse angled corners as well, these murdered things like square or other irregular shaped components in both steel & cast iron & saved the company vast amounts of money! If you are as tight fisted as I am it is perfectly feasible to make your own, don't ask me how I know, set out from positive rake tips in the home workshop.

BobH

i have a Sandvick branded one that I regularily forget to use so the pile of inserts with good 80° corners just keeps piling up.

Rhombic inserts do a decent job at both turning and facing when the tool is set at 90° to the bed that its so convenient not to bother changing. Especially as being a mostly HSS guyI don't use "that" many inserts. Averages out about 2 or 3 a year so the bargain stash of 6 Sandvick boxes bought "mumble-mumble" years ago is lasting well.

Clive

Edited By Clive Foster on 29/04/2021 08:51:25

An old describtion of a homemade,ultra-rigid

Toolingship

I had exactly the same problem and I was guided towards Jenny Blackwell of JB Tools. She has exactly what you want at the right price and I believe they are made in the UK.

Andrew.

Another vote for JB tools

Hello

I've sent a detailed article to Neil (MEW editor) on how to machine these tip holders and others, just wait for the publication.

JM

Greenwood Tools used to sell such holders so that the 100 degree corners could be used. They are shutting down, so be quick and take a look, if Jenny Blackwell can't help you.

I use mine for roughing, but they give a good finish anyway.

Howard

Edited By Howard Lewis on 29/04/2021 12:25:14

I

JB Cutting Tools

Thanks all - just what I needed. I have bought inserts from JB (and had excellent service), but didn't think to look there. An order will be winging its way to JB.

Niels - thanks for the link to your ultra-rigid holder. That looks good. Apart from your holder, the thread is informative in general about the use of carbide tooling in a home workshop.

It's sad to hear that Greenwood is closing. I have a KIT-Q-CUT parting tool which I bought from them years ago at a show (remember shows?). It's a wonderful tool - zips its way though pretty much anything.

Robin.

Hello Graham

Thank You for kind words.

There are pictures of Your lathe in album.

What is size of lathe and can I have a picture of the headstock with internals?

And spindle bearing numbers?

I am interested as the screwcutting geartrain seems to be the same as in my future (and latest. I swear) dream lathe.

Chineese of course and a 38mm bore for 1000$ called CJ0625.

The same gentleman explain carbide part off tooling (and I hijack the thread here)

Step parting

Edited By Niels Abildgaard on 30/04/2021 09:15:08

Hi Neils. My lathe is of the generic Chinese 12x36 design - there are many variations, but the particular variant I have came from Axminster Tools. You can find a manual which gives some info about the headstock / screwcutting gearbox internals here . In the US Grizzly used to sell a very similar machine, marketed as a gunsmith's lathe - the (rather more detailed) manual for their variant can be found here . The Grizzly headstock spindle and gearbox arrangements appear to be identical to those in my machine, but the threading / power feed box is somewhat different.

[Edit] I had a quick look and it seems the CJ0625 - if that's the one you're looking at- is an entirely different animal, so the above might not be of much use!

If I can help further it might be better to continue discussion by private message, as its a bit off-topic here.

Thanks for the link to the discussion of carbide parting tools on HMEM. Your step parting technique is interesting - as well as the Greenwood tool (which uses 2.2mm Sandvik Coromant inserts I think) I have an ARC tool which uses 3mm GTN inserts, so it could be a useful method for me in some circumstances.

Robin.

Edited By Robin Graham on 30/04/2021 23:11:42

Edited By Robin Graham on 30/04/2021 23:15:04

Edited By Robin Graham on 30/04/2021 23:18:17

Hello Robin and thank You for links.

Exactly what I wanted to look at.

The CJ0625 is a very different animal but the procedure described in the Grizzly manual of Yours is universal for adjusting spindle bearings and has been bookmarked.

Niels

Another thumbs up for JB tools, great service from Jenny and some spare tips thrown in free gratis.
first time I have used them, but not the last.

ian

The Glanze holders I bought from Axminster came with this card:

SCBCR and SCKCR use the 100 deg corner.