Thread cutting on a lathe.

[brightspark]

Join the dark side. Insert tools are a doddle

and over expensive and not always needed I always used them at 1st and thought they were brill cos I couldn't sharpen tools rarely use carbide or insert tools unless on hard materials

 

[Seadog]

They are, but so easy to use.

 

[brightspark]

They are, but so easy to use.

all tools are easy to use providing there sharpened properly the most I've spent on lathe tools in 45 years is 75 quid all second hand and I use them regular

 

[mechman]

Used to use hss tools for screw cutting many years ago(sound like uncle Albert) but nearly always had to use a thread chaser afterwards to tidy the thread up.

 

[Hood]

It all boils down to material type and how long you want to spend on a job.
I do mainly stainless and Duplex or harder steels EN19 etc so although HSS will cut them they don't last to long and it takes time to regrind the edge. If you are doing it as a hobby and by that I mean the actual lathe work is the hobby and not a means of producing parts for your hobby, then HSS will likely do fine. If turning for a living or needing to get parts done as fast as possible then Insert is the only way to go.
I still occasionally make up a form tool out of HSS but it is very occasionally, last one was probably 10 years ago or more and if I had had the CNC at the time I wouldn't have been using a form tool.

 

[KMP]

Slim-boy-fat, the range of available change gears for a Myford is large and there is a set to cut metric threads on an imperial machine. Because of the gear size of the metric conversion gear trains a different gear quadrant with a longer slot is required to accommodate the sets. If you have a manual then there is no alternative to counting the teeth, most original Myford gears have the number of teeth cast into them. If you have some of the "clone" gears that abound which are not marked then like me it is counting and then painting the number on. The standard set of gears will be listed in the manual or sometimes on the information plate on the stand if it came with one. A quick google will find a number of sites that list such things, the one thing about owning a Myford is that information is widely available.

With regard to your tooling, most of us "old gits" will have started with HSS (if not Carbon Steel) and they are really versatile and will in general if ground correctly produce a better finish on normal steels than the cheaper indexable sets. A HSS blank is really cheap these days being less than one tip for the indexable tools. Sharpening is not the "black art" that many like to claim and the angles are really very forgiving when you start. One thing I would recommend is that you don't bother with the cheap Tungsten Carbide sets that are available, they chip very easily and are more difficult to sharpen requiring a "green grit" or diamond wheel.

Have fun with the lathe, I have spent many happy hours producing swarf by the bucket full, finished items are a little rarer.

Keith

PS Like many I now use mid range indexable tools, Glanze seems to do me fine being a reasonable balance between price and quality. Be careful with the Myford they are a little slow for most tipped tools to be at their best, and they do not like the industrial negative rake tooling as they lack a little in stiffness and power.

 

[brightspark]

It all boils down to material type and how long you want to spend on a job.
I do mainly stainless and Duplex or harder steels EN19 etc so although HSS will cut them they don't last to long and it takes time to regrind the edge. If you are doing it as a hobby and by that I mean the actual lathe work is the hobby and not a means of producing parts for your hobby, then HSS will likely do fine. If turning for a living or needing to get parts done as fast as possible then Insert is the only way to go.
I still occasionally make up a form tool out of HSS but it is very occasionally, last one was probably 10 years ago or more and if I had had the CNC at the time I wouldn't have been using a form tool.

correct times money in business hobby a different kettle of fish

 

[Richard.]

They are, but so easy to use.

They are easy to use and I love em for the speed and visual appearance I can get from a finishing cut but there is a great satisfaction getting a beautifully turned part or accurately turned thread from a tool made up by my own hands. Those inserts are also very dear and one wrong turn sees them down by an edge as I've managed to do a couple of times. It's kinda catch 22 because they are good for beginners in one respect with there simplicity but very bad for beginners in the respect at £3-5 a pop it will soon cost a fortune till you learn to look after them. I'm still a beginner with the lathe game but I blunted plenty of hss before trying out the inserts. Now I use both.

 

[brightspark]

majority of time I use this . quick to sharpen it used cobalt hss 1/4 bits https://www.google.co.uk/search?biw...g-8Dc#imgrc=neXoQ9HaEwe2eM:&spf=1503437858729

 

[Hood]

PS Like many I now use mid range indexable tools, Glanze seems to do me fine being a reasonable balance between price and quality. Be careful with the Myford they are a little slow for most tipped tools to be at their best, and they do not like the industrial negative rake tooling as they lack a little in stiffness and power.

Glanze are indeed decent tools for a small lathe and also as you say a positive insert for a small lathe is best. You can even get HSS inserts for indexable tools although they are usually more expensive than carbide as they are highly ground and polished and very sharp.

 

[addjunkie]

Learning to grind tools and drills for that matter is all part of learning to use a lathe. To those of us old enough and lucky enough to have been properly taught as apprentices it is second nature. But it is a skill worth learning, as Richard points out earlier it adds to the job satisfaction in hobby use.

But I tool use tipped most of the time now, mainly as I keep the most commonly used tools set up in tool holders ready to use, with HSS each grind up it needs resetting.

Though I have learned if machining some rusty old piece of what ever that is rough as, HSS is much cheaper. I went through 5 tips machining the back plate of one end of a pair of trailer axle. And one HSS re gring for the other 3 ends.

 

[Pete.]

If you can find it, get some stellite tool blanks. They are ground just like HSS only it's much harder and doesn't soften when you get it red hot.
I grind threading tools from stellite it holds the edge very well.

 

[Hood]

Internal threading the easy way

http://www.mig-welding.co.uk/forum/threads/stuff-you-have-made-today.67127/page-69#post-1040989

 

[slim_boy_fat]

Well, curiosity has got the better of me and today I sent off for a r/h Glanze indexable turning tool [with insert], just to try.

Also, I've checked the gear set I have and they are as follows: 20 30 35 45 (x 2) 50 55 65 70 (x 2) and 75. Haven't checked those on the lathe as I'd have to clean and possibly remove them to see the numbers. Can i Assume this is an imperial set?

 

[KMP]

Hi, standard gear set for an ML7 or Super 7 is:

2 x 20, 25, 30, 35, 38, 40, 45, 50, 55, 60, 65, 70 and 75t

With the addition of 2 x 21t gears a range of metric threads can be cut. The mathematically correct change wheel for imperial to metric is a 127t gear which is too big to fit on the lathe so either 63t or the 21t gears are used, while they are an approximation the difference in the real world is very small and they are perfectly fine for normal use.

The very early machines with a gearbox needed a different set.

So guessing that some of those missing in your list are on the machine, it looks as if you have a standard imperial set.

Keith

 

[slim_boy_fat]

Thanks @KMP , much appreciated - hope you're right and the others are already fitted on the lathe. Judging by what came with the lathe by way of extras, I can't see that the previous owner would have had anything other than a full set of gears.

I should get a chance to be out there later today so will try to identify those which are fitted at the moment.

 

[Rannsachair]

Hi, standard gear set for an ML7 or Super 7 is:

2 x 20, 25, 30, 35, 38, 40, 45, 50, 55, 60, 65, 70 and 75t

With the addition of 2 x 21t gears a range of metric threads can be cut. The mathematically correct change wheel for imperial to metric is a 127t gear which is too big to fit on the lathe so either 63t or the 21t gears are used, while they are an approximation the difference in the real world is very small and they are perfectly fine for normal use.

The very early machines with a gearbox needed a different set.

So guessing that some of those missing in your list are on the machine, it looks as if you have a standard imperial set.

Keith

I picked up two 21t gears so O can cut metric on my Imperial ML7, as you say works well enough.

 

[slim_boy_fat]

I sent off for a r/h Glanze indexable turning tool [with insert], just to try.

It arrived, and I have......just on a bit of scrap aly, but it produces a good finish. But those who use these will know that already .
Might add others as time passes. Next up, I need to grind a parting tool from HSS - be good practise, every day a school day......

 

[Hood]

Next up, I need to grind a parting tool from HSS - be good practise, every day a school day......

If I was only allowed to use one inserted carbide tool and all the rest had to be HSS, then the one I would choose is a parting tool.

 

[addjunkie]

What I will say if increasing your tipped tool collection, try to get extra tools with the same tips, saves loads of hassel.