Best Parting off tool

I don't think my HSS blade would have a prayer on hardened races, but that's rather an outlier of a requirement and I've certainly never needed to do anything like that.

Even the link admits in the notes at the end that conditions and techniques for parting can be highly idiosyncratic. That old cartoon set I keep seeing here and in magazines illustrates only the extremes of a multidirectional spectrum.

I think nothing is ever perfect in all conditions, and that there ain't no best parting tool.

Mick,

I think you may have missed this bit:

It has a strip of carbide along the top of the T

Nah, saw that :D - and I'm sure it's good if you're trying to cut hardened stuff, but that doesn't necessarily make it the answer to every issue.

Having experienced difficulties with the "Greenwood" type unless the TC bit was sharpened regularly on a diamond or CBN wheel, I followed a suggestion made by the owner of a small precision eng company. This was to part off with a slitting saw mounted on an arbour. Probably known to you all and It no doubt breaks all the "rules" yet works very well. When the contact tooth gets blunt, just rotate a little & use new one. New slitting saws aren't cheap but seem to appear in abundance at our M.E.Soc's auction nights. (The image shows parting PEEK CA30 piston rings).

The "Greenwood" type as referred to is a standard insert tool, (other makes are available). If you find you have to sharpen with a diamond (frequently) you are rubbing your way through and not cutting, These inserts need a strong and sustained infeed at the correct height..

That is exactly my experience with the Greenwood tips. I found if I made it work. E.g. 50mm EN8 1000RPM power feed blue curls coming off the finish was better than I could get when facing with other tips. If I am honest it was a bit scary but my goodness they work well. However like I posted earlier I wore out the holder. I cannot recommend those Greenwood tools parting tips highly enough for performance and finish. The GFN-2 (JB cutting tools) and GFN-3 (ISCAR) tips I use now (Greenwood's were 2.6mm) are similar but not quite the mirror finish, good enough for me though.

Do you have a link to a standard blade holder either 19 or 26 size that takes these sandvik tips?

Thanks,

Steve

With your +ve comments about the "Greenwood" tips, do you both also use the standard holder? (The one shown unused in my image above). I'd be grateful for some guidance then because even though I carefully align the vertical "tip holding plate" parallel with the chuck body, it apparently flexes enough to end up with a distinctly dished cut-off piece. There's no discernable sideways movement in the top slide and the saddle is always clamped hard to the bed.
I had been using the TC tips from JB in the original Greenwood holder. Those showed this angled cut and I wondered if this caused the concave surface after parting (which doesn't show using the slitting saw & is thus now used exclusively).

Its not about rules. The teeth are generally fine pitch and you need to ask how the swarf can escape from the throat of the tooth that's doing the cutting.

Murray

Most suppliers keep these parting tools, eg Arc, APT Tools and all the usual ebay / Ali Express traders.

Murray

In my experience, every time you put an angle on the end (usually the other way so there's no pip on the part being parted off), the blade does flex giving a dished surface.

Neil Wyatt:

Thanks for the link which, however, takes me to a page where the only reference to "carbide" is to indexable carbide tipped tools.

Its a left hand parting tip for leaving best finish on the left of job.
Looks rather rounded even though unused.

Right hand opposite of above leaves in theory clean finished cut to the right.

Neutrals just neutral.

Try Iscar tips wont go wrong.

Really? There’s no mention of any carbide strip on the blade on the website. It just says M42 HSS.

**LINK**

Strange... that link takes me straight to the front or rear parting tool

If the tool isn't fifth down on the menu to the left, then you need to clear your cache and reload the site.

Neil

.

... but where is there any reference to the blade having a carbide 'top' to the T

?

MichaelG.

Really? There’s no mention of any carbide strip on the blade on the website. It just says M42 HSS.

Don't ask me. I only quoted from Hopper's post. He is the one to ask!

Perhaps you are not looking in the right place? You had better ask Hopper, or even his mate.

Edited By not done it yet on 08/12/2017 22:13:21

> Chris T anhd Jon,

Many thanks for your comments.
I have used Iscar tips for general turning and found they performed well so I'll certainly try a couple for the p/o holder and hopefully start using it again.

"Looks rather rounded even though unused."
My thinking too & why I began to sharpen them on a diamand wheel, after which they cut much better. Here's that same new tip from the side:-

Hi All

Thought I'd just clear up the confusion with the carbide tipped "T" type blades question.

I used to sell a 1mm and a 1.6mm wide blade with a brazed on carbide strip about 16mm long but I didn't sell many as they were quite expensive so I discontinued them a while back.

If anyone really needs one they can still be purchased through Somma Tooling in the US but I've just had a look at their website and a 1/1/6" tipped blade is now US$44.50 + postage so fairly pricey.

They also make solid carbide ones if you want to fork out US$83.50. You wouldn't want to snap it on the first job

Cheers

Gary

Eccentric Engineering

Thanks for clearing that up, Gary.