Lathe Noob With Some Questions On First Cuts

[mikey]

I meant no insult, Brino. I don't think discussing fluids here will hijack the thread - Tony can use the info, too.

In terms of cutting efficiency and tool life, WD-40 works fine for Aluminum but not for steel under relatively high cutting loads. My reasoning over the years is that since WD-40 has a boiling point the the mid-300's it loses most of its lubricating properties with heavier cuts in steel where temps at the point of cut can be quite high.

I think we all try different stuff and settle on what works for most things. I like Tapmatic #1 Gold for most stuff, heavy sulfur-based oil for thread cutting most stuff, A-9 for aluminum when I need the best finish or WD-40 for routine turning and milling of aluminum. No one thing works for everything and everyone will have their favorites.

 

[brino]

I meant no insult, Brino. I don't think discussing fluids here will hijack the thread

Mike,

Absolutely no offense taken!

I had not considered boiling point, there's one more parameter......sigh.....

I think we all try different stuff and settle on what works for most things.

Agreed, our requirements vary greatly. At the top of my requirements list is for what ever the fluid is NOT TO FREEZE!
(I'm guessing that's not on your list ).
Since I cannot guarantee that my garage shop will be above freezing in the winter months.

Tests I've done on some of the soluble oil coolants that you mix with water showed that at the recommended dilutions they do freeze.

Sure the true cutting oils will not freeze, but I'm considering fluids for my power hacksaw and mill too.
My big old mill has coolant slots in the table and a reservoir in the base, but I've (so far) never used them.
Currently I just hand apply small quantities with a spray bottle or brush.

-brino

 

[Bill C.]

This is the only place I've read of using WD40 as a cutting fluid. I had used heavy cutting oil with the turret lathes I was assigned. I have used water based coolant with grinders, saws and milling machines. I don't know if the water based coolant would freeze or not. Cutting oil probably will stiffen up when it is cold. Interesting question

 

[Pinresto]

Hijack away. I need to buy a cutting fluids. Right now I'm using the same ISO 68 I'm using for my lathe. Not ideal im sure but It's probably the best of what I have on hand. I'll need to order some and it will take two weeks to get here. Today I found a shop locally that sold some machining stuff. Some starrett micrometer, calipers, lathe tool blanks, reamers, etc. it's nice to find one so close to me. They probably have cutting fluids but my command of the local language in limited at best. I'll stop back by when my translator (wife) is with me to ask some questions.

 

[Pinresto]

Mike, I'm going to post some more pics of my tool. (Lol) All I've done to it is hone it and put a slight radius on it. I'm home now and ready to go at it again. I'm going to read through your post again and make your suggested adjustments.

 

[Pinresto]

 

[mikey]

As suspected, you have no end relief angle on that tool and it will not be able to penetrate the work except with brute force. May I suggest you see the links in post 70 in this thread?

http://hobby-machinist.com/threads/turning-tool-and-facing-tool-questions.36687/

Have a look at the articles with particular attention to how to grind the various shapes and angles and then have a go at grinding the tool again. I hope it helps.

 

[T Bredehoft]

Aside from what looks like a worn nose radius, it looks like it should cut well. If the radius is just honed, go for it, if it's worn shiny,regrind the end until its' gone.

Edit: maybe a little more vertical relief on the end, try 7 to 12º under cut.

 

[janvanruth]

there are some good videos on youtube on the subject of grinding cutting tools

 

[Pinresto]

I made the adjustments you suggested and its def an improvement. I'm going to start again from the beginning after I read through the three part article on machinist blog. It's really good info. I had actually started reading it before you suggested it. I've got to run out for the evening but I'll post pics and an update tomorrow.
Thanks, your help is much appreciated.