Single Point Threading Tool

[DaveH]

A few pics showing the type of tool holder and inserts I use for single point threading on my lathe.

The same as the one used here . http://www.metalworkingfun.com/showthrea...94#pid2794

A view of the business end
   

Both the same holder, the silver coloured one is just newer, and has the threading insert, the black one (on its side) has a small profiling insert – or more specifically a rounded end grooving insert

To the right another threading insert and a grooving insert (straight ended)
   

Shows how the tool angles the inserts to achieve the correct cutting angles
   

The threading inserts are either 60 deg or 55 deg. Shown by MT=60deg; WT=55deg.
   

The insert at the bottom in the above photo is chipped. What happens if you allow the work piece to turn backwards.
   

Some more photos.
   
   
   

All the inserts are interchangeable, some different sizes makes it quite a versatile tool holder.

DaveH

[EdK]

Dave,

I like those tools, especially the fact that they'll take a grooving and form insert besides the threading insert. What brand are those tools?

OT: What brand and model is your new camera? Just curious since I have photography as a hobby also.

Ed

[DaveH]

Ed,

Iscar - GHSR 12-2 this one http://www.iscar.com/Ecat/familyHDR.asp?...=1&lang=EN

My camera is a canon point and hope "ixus 220 HS"


DaveH

[PixMan]

That's a proprietary, though more rigid version of something that's been available for over 40 years: Top Notch grooving/threading tools.

Kennametal had developed the tooling system long ago, and distributed it widely. The patent had long run out, and now Walter Valenite, Tool Flo, and myriad other companies make the holders and inserts for them. There are 3 basic size groups, a 2, 3 and 4. If they ever made a tiny "1" size or a larger "5", I don't know about it. The 3 is the most popular, by far. I have them in left and right hand holders.

With the Top Notch system, you can also find a huge variety of different threading and grooving inserts, though parting inserts are very limited. The Top Notch inserts are much cheaper and easier to find. Iscar did a good job with that, but they never stick with anything as long as the Top Notch stuff has been out there.

[EdK]

Ken,

Thanks for the information. I've been eying the Top Notch stuff for awhile since I see them mentioned all over the internet. Good to know the inserts are easy to find and cheap.

Ed

[Tony Wells]

Top Notch is, well......top notch. I have some tooling in that configuration and highly recommend it.

[PixMan]

I should refine what I wrote in my post above. When I used the term "more rigid", I meant only that the insert is, technically speaking, held more securely than a Top Notch style insert.

In the Top Notch system, there is a groove molded into the top side of the insert. The groove (or "Notch" as it refers to) is at about a 45º angle. The pocket in the tool holder is almost square and flat (most people don't realize there's actually about a 3º inclination angle) and nothing in the pocket secures the bottom of the insert. The tool holder's top clamp pulls the insert back into the pocket as it pushes down.

The Iscar tool shown, as well as the myriad other choices from other makers, has V-grooves on both the top and the bottom of the insert, and corresponding features on the holder make for a very secure, bi-directional grip on the insert. With certain groove/turn type of inserts, you can easily do some fairly heavy duty turning with the tool. When doing that, the holder's "support blade" carrying the insert is engineered to flex a bit so that the insert isn't rubbing the whole face as you traverse from left-to-right or right-to-left. That flex, though slight, is there and is why most other makers of similar tools do not offer threading inserts in their double-ended grooving/parting tool systems.

By contrast, the Top Notch is only good for cutting pressures from the 90º quadrant opposite the holder's insert pocket nesting corner. The makes them good for compound infeed threading and suitable for straight-in grooving. I use the Top Notch for threads coarser than 8 threads per inch and for snap ring, O-ring, and thread relief grooving. I might also use the Top Notch threading inserts for any thread that I don't yet own the proper pitch-specific lay-down 16ER/IR insert. There are now available a limited range of cresting (full form) threading inserts for Top Notch, but they are harder to find and probably the same money or more than the relatively easy-to-find 16ER/IR styles.

I'll try and get some photos of both styles. This is another case of a picture is worth 1000 words.

[Rickabilly]

I was using Top notch in the late eighties, they were good reliable tools, Iscar are always good but I found them as expensive as they are good so I tend to stick to Kennametal, Old habits!

I may be a dinosaur but I still like HSS for threading and grooving, I like control over my geometry in a way that indexable tools just don't allow, and when threading I like razor sharp tools which gets expensive when you need to replace tips to get that razor sharp edge for the finish cut, with HSS I take a minute before the finish cut and polish the edge with a diamond file, Lovely.

Best regards
Rick