Need Good Single Point Threading Tool

Yes HSS, Yes Carbide

Learn to grind HSS very versatile for one off jobs(also rewarding). Atlas/Southbend how to run a lathe have very clear illustrations of tools for general work, photo copy, put in a plastic page, set it by grinder lay tool on it as you grind. will clearly show your work progress. A can water to cool tool, fingers. Learning is the fun/interesting part starting out and thirifty.
 
Beautiful threads, Dark Zero!
To all you guys who like hot fingers and eating grinding dust, hope you can hit 60 degrees along with proper clearance for the helix angle of your intended pitch and diameter. I am sure you can, but to the novice, this is a challenge. LT (Laydown Triangle) inserts are often interchangeable with several manufacturers. Sandvik is an exception by making a thicker insert. You must always pay attention to the Anvil/Shim under the insert. Notice all LT inserts have no relief ground into the Flank Face of the insert. In order to gain axial and radial relief (clearance) the insert is tilted in the negative plane. However, to produce a coarse thread one day and a fine thread on a different day at a different diameter may require a different Anvil. Every degree of helix angle requires a different Anvil. Each anvil is typically good for +/- 30 minutes. For this reason, I prefer Kennametal Top Notch, Widia Top Thread, or Sandvik Top Lock. The inserts, both threading and grooving, and holders are interchangeable by replacing the top clamp and the inserts have enough clearance ground into the thread form to produce a majority of common threads. In the Kennametal product line, use the grade KC5025 or Widia, use grade TN6025. Both inserts are quite tough (IMPACT RESISTANT) and should do a fine job at really slow speeds, even on those less than ideal machines. Just cut some 1/2 and 7/16- 20 threads a couple days ago on 303 SS at 75 RPM without a bit of difficulty. The key is using a tough, sharp, grade as mentioned above. No matter who the manufacturer is, to obtain a sharp edge the insert must be ground and uncoated or PVD coated only. CVD coatings will not deliver a sharp edge.

Good Luck,
Gary
 
I too, am spoil to using inserted tooling for threading. I did my share of tool grinding in my early years of machining. But when inserted threading tools came available and reasonably affordable to us individuals, that all I use today.
One thing I have learned about the carbide inserts, threading inserts do not like a heavy honed edge at all when used on light duty machines as many of us have. It's kind of a crap shoot trying to get a unhoned insert. You usually are stuck with what is available at the time ordered. I will say, most inserts today, have fairly sharp edges with minimum hone to them. That makes it nice today! Last, get you some good cutting fluid to use while threading. Mobile makes some nice cutting oils available in 1 gallon jugs for around $30 that work great. I like using it plus mixing in with Tapfree!
 
It's straight forward to make Cleeve's jig to sharpen HSS threading tools. It's not quick to grind a threading tool from a blank because considerable HSS must be ground away. However, the jig makes it easy to get the angles right and also makes resharpening quick and easy because the angles can be reproduced exactly.

See: http://www.gadgetbuilder.com/ThreadingTools.html

John
 
I bought this 5/8" carbide insert threading tool from Shars:

http://www.shars.com/5-8-x-5-8-indexable-cutting-tool-universal-external-threading-tool-holder

I have ground my own HSS, and also used 60 degree brazed carbide cutting tools. Last fall I watched a tubalcain (mrpete222) video about the "Machinability of Steel" parts 1 and 2 (#175 & #176). It was very interesting because he was experimenting with this new carbide insert thread cutting tool. As it turned out, hard to thread metals were not nearly as hard to thread with this tool. The thread quality is excellent, and it is also relatively cheap at $37. I bought the corresponding internal thread boring bar as well, and am very happy with them both. I use the AG-60 IR and AG-60 ER carbide inserts which allow threading from 8 to 36 TPI. Buy your replacement inserts on eBay, they are cheaper.

Many of the old issues with carbide not working well in smaller machines have gone by the wayside. The new insert shapes and coatings perform quite well, and sizes are available that match up well with smaller machines.

Just my $.02

GG
 
In using carbide insert or even brazed in carbide threading tools, one MUST provide a run out recess for the end of the cut, otherwise, chipping or breakage is inevitable. I agree that one should learn to grind their own tools in HSS; I have been at this craft since 1962 if you count high school machine shop class, later apprenticeship, then journeyman, then my own business for over 40 years, now a home shop, and the very first thing that I was taught was how to sharpen cutting tools; we were issued blank tool bits, and kept them for the remainder of the class. Today I seldom use tool bits, except for special shapes or forms. For external threading, I use a shank type tool with a formed bit that is sharpened only on the top, made by Pratt & Whitney, bought on e bay. I also have one of the formed cutters that Aloris sells, but I like the P&W better because of the long shank that allows its use in tight quarters when I have to support the part with the center, For internal threading I use a form relieved boring bar from BOKUM Tool Co. it too is sharpened only on the top, and are sized for various diameters, some quite small. They also make boring bars in lead angle, and flat bottom configurations. If you were using a big CNC lathe, carbide would make sense, on small hobby style machines, it does not make much sense.
 
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Darn Will, when I see threads like those it makes my mouth water and I have the urge to go cut some threads just for the sake of cutting threads. Sorta like a picture of a big greasy, juicy hamburger makes you crave a big greasy, juicy hamburger. Nice job!

Tom
 
+1 on the nickole, I have both the R and L, love em, I also have the carmex tools, they are great as well, I had an import threading tool that used the single end Carbide Insert, sold in a set from shars, straight garbage, the tip of the insert broke on aluminum, junk junk junk, I also broke the parting tool that came in that set, I now use an aloris 77-I holder with an iscar self grip blade, I no longer buy Chinese tools, a used brand name tool is 10x better than a new China made, I will admit though, that SOME of the inserts from China have lasted a long time
 
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