I fairly recently bought some tungsten? tipped screw cutting and boring lathe tools from a well known model engineering supplier who advertises on the internet and who has supplied other things in the past which have been satisfactory.
Tried out one of the boring tools a week or so ago. Needs completely re shaping before it will be of any use for cutting any type of metal . Yesterday I tried the external screw cutting tools on a series of 8 number
5/8" bolts on which a local fisherman needed an M16 2.0 thread to bolt down a new six cylinder Cummings engine. Both tools failed and are now scrap. I finished the job with an HSS Myford tool which I have had and used for over 40 years.I myself am not over worried, the tools were cheap and I should have used my better judgement. However any newcomer might well buy on price and even his best efforts will be disappointing.
I am sending the tools back to the supplier to do with them what they will.
In the 1950's and 1960's a tool supplier or even a local ironmonger had a choice of tools of quality. I have many which are as good as the day they were bought and are a joy to use. I also have joiners planes and chisels dating back to the turn of the last century which will take an edge like a razor and hold it.
Better stop now before boring you further
Donald South Uist