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Establishing a referance Point in the z-axis
- Thread starter chiroone
- Start date
- Joined
- Dec 6, 2012
- Messages
- 2,677
One of my mentors taught me to mic a scrap of paper.
With the machine off very slowly raise the knee while moving the paper with your fingers. Stop when she first starts to drag.
That puts the cutter off the top edge by that distance. Sometimes I do this several times and check repeatability to confirm my reading.
If I'm in a hurry and tolerance is pretty wide, then I'll lick or oil the paper. With the machine off. I place the paper under the tool and move my finger4s away. Then start up the machine and raise the knee until the paper moves.
Daryl
MN
With the machine off very slowly raise the knee while moving the paper with your fingers. Stop when she first starts to drag.
That puts the cutter off the top edge by that distance. Sometimes I do this several times and check repeatability to confirm my reading.
If I'm in a hurry and tolerance is pretty wide, then I'll lick or oil the paper. With the machine off. I place the paper under the tool and move my finger4s away. Then start up the machine and raise the knee until the paper moves.
Daryl
MN
The wobble thing is called an edge finder. Put a piece of paper on the work and bring the cutter to it. When it gets thrown out by the rotation of the cutter, bring the table up the thickness of the paper.
Please read the safety instructions before you fire that mill up.
Please read the safety instructions before you fire that mill up.
- Joined
- Dec 6, 2012
- Messages
- 2,677
Attached is a copy of a Wiggler Manual. Yes, it's a manual from a General. If someone finds a better manual I'd be thankful for it!
Addtionally, please note the cut/paste from Burley. These are not indicators. They don't tell you how much you are out or which direction.
Testing Machine Tools: Burley p38-39
"Non-measuring Indicators. — These instruments (sometimes called " wigglers ") do not admit of the actual measurement of errors, though they enable the presence of errors to be detected. They usually work on the principle of magnification, the operation of which causes the movement of the indicating element to be several—in some cases, many—times as great as the actual error, whether this be one of eccentricity or obliquity. As instruments for use in precision testing they are practically worthless except in those cases wherein only qualitative results for the purposes of correction are required."
You can use them to edge find, and check parallel of the X, Y or Z. (note that the depth is limited to the length of the stylus). It's really handy device for finding center when on the DP!
There may be more precise methods. But, she is quick, easy and if you accidentally drop her your stomach won't get queasy.
Several local mentors have beat into me the idea that everything really comes down to "fit for use".
Daryl
MN
Addtionally, please note the cut/paste from Burley. These are not indicators. They don't tell you how much you are out or which direction.
Testing Machine Tools: Burley p38-39
"Non-measuring Indicators. — These instruments (sometimes called " wigglers ") do not admit of the actual measurement of errors, though they enable the presence of errors to be detected. They usually work on the principle of magnification, the operation of which causes the movement of the indicating element to be several—in some cases, many—times as great as the actual error, whether this be one of eccentricity or obliquity. As instruments for use in precision testing they are practically worthless except in those cases wherein only qualitative results for the purposes of correction are required."
You can use them to edge find, and check parallel of the X, Y or Z. (note that the depth is limited to the length of the stylus). It's really handy device for finding center when on the DP!
There may be more precise methods. But, she is quick, easy and if you accidentally drop her your stomach won't get queasy.
Several local mentors have beat into me the idea that everything really comes down to "fit for use".
Daryl
MN
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