# Tramming vise on mill



## Investigator (Aug 28, 2017)

Just want to make sure I understand......
This is in reference to a RF30 type round column mill:

After I fit the vise to the mill and get it trammed, if I raise the head I dont have to re-tram the vise right?  The jaws will still be perpendicular to the spindle even if the spindle has moved up and possibly over a bit.  Not talking about tool changes, but between parts.

For example, Say I have the vise trammed in and all is good.  I make a part and move on to another project.  Some time later I have a new project and new part to make.  I realize I dont have enough spindle height for the new part so I raise the head.  Now I have enough spindle height and put the part in the vise.  At this point is the vise still trammed correctly even though the head moved up (increase in z axis) and possibly moved to the side a bit?


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## mikey (Aug 28, 2017)

Just leave the vise alone and bump the head to align it to the vise, then tighten and check. You may have to do this a few times because locking the screws that tighten the head to the column can move the head a tiny bit. It's a hassle but you get used to it quickly.


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## T Bredehoft (Aug 28, 2017)

You are correct. the relationship between the vice and the table doesn't change when you move the head. Just don't asume that X and Y zero will be the same after  you move the head.


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## Silverbullet (Aug 28, 2017)

Wouldn't a laser pointer mounted on the head be able to relocate the head back to the same spot within a few thousandth. Or two to intersect on one Spot.


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## T Bredehoft (Aug 28, 2017)

Silverbullet said:


> a laser pointer



I tried that with mine, 15 feet away the laser dot is about 3/16 inch and fuzzy. Is there a more precise laser available? I tried both a freehand pointer and a commercial (but cheap) level with a built in laser.


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## kd4gij (Aug 28, 2017)

Silverbullet said:


> Wouldn't a laser pointer mounted on the head be able to relocate the head back to the same spot within a few thousandth. Or two to intersect on one Spot.




I read a thread on another board where a guy drew a thin vertical line on a wall and used a laser mounted on the head just for that.


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## kd4gij (Aug 28, 2017)

T Bredehoft said:


> I tried that with mine, 15 feet away the laser dot is about 3/16 inch and fuzzy. Is there a more precise laser available? I tried both a freehand pointer and a commercial (but cheap) level with a built in laser.




 Yes but there not cheap.


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## Silverbullet (Aug 28, 2017)

Couldn't it be pointed at the base of the mill and it work the same . I would think it would be more accurate using the permanent base then a wall or ceiling. Even turned if it's lined up on the same spot.


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## Bob Korves (Aug 28, 2017)

3/16" over 15' is a quite small angle, .19 degree if the dot is off by one entire 3/16" diameter, which is unlikely.  That works for repeatably squaring round mill heads to the table.  Over the distance from head to table, 3/16" is a much larger error.  Those machines often have errors with the Z axis being not perpendicular to the X and Y axes such that real accuracy will not be attainable without resetting the column of the machine so the travel of the head is in a line perpendicular to the table axes.  Even then, the quill travel axis may not match the Z axis of the head travel.  Those machines can be made quite accurate, but it takes some understanding of what causes the errors, then reading them, and then fixing them in a proper sequence to make comprehensive progress.  Lacking that, the errors just get chased to another axis.


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## kd4gij (Aug 28, 2017)

The best setup I have seen was the guy used 2  1" linear rails 1 on either side of the head with 2" long bearings.


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## FanMan (Aug 28, 2017)

Are you talking about tramming the vise in the x direction while you move the table or the z direction while you move the head?  Because in the first case, you're not tramming it to be square with the spindle even though you're putting the indicator in the spindle; you're tramming it to get the fixed jaw of the vise parallel to the x travel.


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## kd4gij (Aug 28, 2017)

I DTI is still your best friend


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## Investigator (Aug 28, 2017)

FanMan said:


> Are you talking about tramming the vise in the x direction while you move the table or the z direction while you move the head?  Because in the first case, you're not tramming it to be square with the spindle even though you're putting the indicator in the spindle; you're tramming it to get the fixed jaw of the vise parallel to the x travel.



Not sure how to say what I mean, but I think we are saying the same thing in your second case above.

Another try:

I buy a vice and mount it on the table.  Using my DTI held in the spindle I get the fixed jaw trammed in so that the fixed jaw is parallel with the x movement of the table. Now I make a widget for a project I am working on.  When I complete the widget, I clean the table, cover the machine and go on to other projects.  Several days, or weeks later I have another project to build.  This time I need to make a whatsit, but to do that I have to raise the head of the mill/drill to have room.  After I raise the head of the mill (without indicating anything), which of the following is correct?

The vise is still trammed for accurate x travel and all that is needed is to find the X and Y edge, reset the DRO and make whatever cuts I need.
OR

because I raised the head, I need to use a DTI and adjust the vise to make sure the fixed jaw of the vise will still travel parallel to the x travel

I think the first option is correct, I just wanted to make sure what I think is what is correct.

I also understand that while keeping the same part fixed to the table or vise that raising the head will cause me to need to use a DTI to find the position again, but that's not what I talking about in this question.


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## Bob Korves (Aug 28, 2017)

Investigator said:


> The vise is still trammed for accurate x travel and all that is needed is to find the X and Y edge, reset the DRO and make whatever cuts I need.


That statement is correct.


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## aliva (Aug 29, 2017)

This problem is why I got rid of my round column mill, a real pain to reset when you have to move the head


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## higgite (Aug 29, 2017)

What am I not understanding about round column mills and the need to re-tram your vise when you move the head up and down? You don’t tram the vise to the head, per se. You tram the vice to the direction of table travel. I don’t see how rotating the head changes that relationship. It just changes X and Y zero coordinates, doesn’t it? Can’t you just re-zero your dials or DRO with an edge finder, like has been suggested? Or is re-zeroing being used interchangeably with re-tramming?

Tom


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## Investigator (Aug 29, 2017)

higgite said:


> What am I not understanding about round column mills and the need to re-tram your vise when you move the head up and down? You don’t tram the vise to the head, per se. You tram the vice to the direction of table travel. I don’t see how rotating the head changes that relationship. It just changes X and Y zero coordinates, doesn’t it? Can’t you just re-zero your dials or DRO with an edge finder, like has been suggested? Or is re-zeroing being used interchangeably with re-tramming?
> 
> Tom



You are correct.  Being a newbie I asked to make sure my thought was correct.  Raising the head only affects the x/y co-ordinates.   Raising the head will not effect the tram of the vise.


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