correct tool height

[gdgambler]

I am talking about a lathe. Is there any trick or easy ways to set the correct tool height on cutoff tools and turning tools.

 

[SwissPro]

On a CNC lathe, measure the tool height before you put it in the machine. I like to use a comparator stand and a drop indicator. Then use a shim to make up the diff. If your holders vary, qualify them and stamp or etch the size into it.

On an engine lathe, use a small height gage. You'll need to figure out the height off of the cross slide first. But once you have it, using a height gage is pretty quick. You can also use a planer/shaper gage if you dont have a height gage.

There are also little gages available that have a "V" that you rest on the work. The other end is a flat that you rest on the tool. In between there is a small bubble level. So the theory being that you get the bubble in the middle by raising or lowering the tool, then the tool will be on center. They're good enough for government work as the saying goes.

 

[nisse]

Another way is to take a face cut, and measure the nub diameter that is left and shim half of that. On a manual lathe a quick and dirty way is to place a rule between your tool and work and bring the tool up until the tool holds the rule against the work, and adjust your height until the rule is perpindicular to the ways. That is the same idea as SwissPro described.
John

 

[John Murphy]

or make one of these--
http://www.frets.com/FRETSPages/Machining/index.html
Look under tooling/ 3rd from btm, lathe tool height setter.
bet you spend at least 1/2 hr looking over the other items! John

 

[G95]

keep in mind part off tools work better a little above center maybe .005"

 

[Advena]

Hi

I sometimes put a sharp rolling center in the tailstock and allighn the tool height with that.
Allways worked for me. On the cnc I make sure to buy the right tool and if it is not in the center I check another tool position and if it is also out you know that the tool turret needs to be adjusted.

Christo

 

[stroker]

Take a trial cut to produce a diameter and then gently hold a straight edge (e.g. 12" rule) between the tool tip and the diameter. The straight edge will be perpendicular when the tool is on centre, or lean to the right or left (when viewed from the tailstock) when too high or too low.
Mike

 

[maxh]

For quick and dirty, I measure my piece of stock in the lathe, lock my calipers at half of that, bring my tool to the end of the stock and raise or lower the tool until my calipers say it's in the right spot. I find this is faster for me than eyeballing my scale pinched between the stock and the tool until it's vertical.

I always put my tools right on the center. If a more negative rake is needed, I change the tool rather than raise it above center. When your tool is not on center the effective rake angle changes as the diameter of your part changes.

Oh, on CNC, I guess test facing cut, measure the nipple, then shim appropriately.

 

[winger]

The scale trick works but not a good idea for carbide. Push a little to hard and the insert chips.

 

[Solar71]

Throw it in and take a test pass...

Bring the tool down to some material...

Take a .03 cut about .25 long...

Read the screen and see what diameter you are cutting at...

measure your material...

If the numbers match, your good to go...
If not, adjust the tool offsets by the same amount that the 2 numbers differ by...

Cut again, check, repeat untill satisfied...

Only other way is to pay 1,000-2,000$ and have a tool-eye installed in your machine...

That way you can just touch off on the tool-eye with each tool, when you make contact the machine will beep and automaticly set the correct offsets for you...

Good luck...