Doesn't exist? -- 8 TPI threaded chuck to fit an 80mm HF faceplate (w/ picture)

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Firebrick43 said:
Any good right hand tool/holder that has a sharp cutting edge and has positive geometry would work. HSS would have the lowest pressure and therefore limit deflection of the shaft.

I personally would use a tangential tool holder but that is because I have one. A CCMT 21.52 RH tool holder (SCLCR) would work as well.

While I still don't know why they do it, a RH tool is meant to cut to the Left towards the chuck.

I personally don't care for triangle inserts most of the time.

I would use HSS for threading but you would need to learn to grind it. I also have a number 1 top notch tool that takes threading inserts that works well but probably more expensive than many want. Laydown threading tool holders seem to be much more reasonably priced but I have not really used the
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So what I'm hearing is the the stock index cutters that come with the HF mini lathe are not the right call. :)

I can be a maniac about acquiring tools that I use once and then end up in a bin. What would your recommendation be for a tool set that would be versatile and reasonably economical?
 
bcrimmins said:
For example, are these crap?

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They aren't great, but they aren't crap. What you run into is that the inserts tend to be molded and not very sharp. That increases tool pressure and deflection of the part. On a mini lathe those can be very important.

You can get honed/polished inserts. They are generally intended for aluminum, but will cut steels nicely. They won't last as long, but will work better, particularly for a small machine.

Grinding HSS is probably the best option for a mini. Get it really sharp and you can get very good cutting with it.
 
ttabbal said:
They aren't great, but they aren't crap. What you run into is that the inserts tend to be molded and not very sharp. That increases tool pressure and deflection of the part. On a mini lathe those can be very important.

You can get honed/polished inserts. They are generally intended for aluminum, but will cut steels nicely. They won't last as long, but will work better, particularly for a small machine.

Grinding HSS is probably the best option for a mini. Get it really sharp and you can get very good cutting with it.
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Oh, so hhs cuts better ( e.g., less pressure) than carbide?

How difficult is it to get good at sharpening hhs cutters?
 
bcrimmins said:
Oh, so hhs cuts better ( e.g., less pressure) than carbide?

How difficult is it to get good at sharpening hhs cutters?
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Yes. Mostly due to the sharpness you can achieve. Carbide is brittle, so a really fine edge can be fragile. HSS has a bit more give.

Grinding and sharpening looks harder than it is. It just takes a little practice to get the feel for it.

The thread mentioned above is what I call the Book of @mikey. It's well worth reading. And with a mini lathe, the bits are smaller and faster to grind. :)
 
bcrimmins said:
Oh, so hhs cuts better ( e.g., less pressure) than carbide?

How difficult is it to get good at sharpening hhs cutters?
Click to expand...
One thing I learned is you don't have to be all that good at grinding cutters to be better than carbide on a lathe. I did pretty well just eyeballing angles and not really going for a particular angle (just watched the ToT video), and did better than the import carbide.

What helped the most was some sort of stone to get a fine hone.
 
Could someone share a link to Mikey's hhs grinding post. He's been a prolific poster and I'm not sure I have found the referenced post. Thanks!
 
www.hobby-machinist.com

Models for grinding HSS Lathe Tools

In a recent thread by @Darkbluesky, http://www.hobby-machinist.com/threads/lathe-accessories-tools-ideas-of-what-to-buy.62043/#post-511618, @ttabbal joked about sending me blanks to be ground into lathe tools ... he was joking! But it got me to thinking ... yeah, I know it's not a good thing...
www.hobby-machinist.com www.hobby-machinist.com
 
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