Mill Tramming tool aid

I read this somewhere on the net but it has been a while and I do not remember where I read it.

My mini mill table is 4" by 16" long and with the T-slots that does not leave much room for checking tram.
I found this Honda brake disc on the bay for $15.00 and that included shipping. Now, the thing weights
a good bit, must be over 10 lbs and that is a good thing.These discs are precisely ground and have a nice finish.

The one I bought has a large hub in the center section which I could do without buy my tramming tool that I made
a while back has positions for small diameter testing and larger diameter testing since I always wanted to get a
precision plate to aid tramming.

Any how here are a couple of shots of the setup. Works great.

My mill was the tilting column variety and I have it locked down. I never tilt it.
I made mine quite sturdy using this process:

Reducing Mini-Mill Column Flex (and Column Y-Axis Alignment) - Home Model Engine Machinist

The bar at the bottom is the secret to a fast and accurate tram. If you have the solid column I think it has a built in set of
stops that can be adjusted.

Cheers, JR

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Thanks jjr2001! We've added your Mill Tramming Aid to our Measuring and Marking category,
as well as to your builder page: jjr2001's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-mill-tramming-aid"> <img src="/uploads/168753/homemade-mill-tramming-aid.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="http://www.homemadetools.net/homemade-mill-tramming-aid">Mill Tramming Aid</a> <span> by <a href="http://www.homemadetools.net/builder/jjr2001">jjr2001</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/milling'>milling</a>, <a href='http://www.homemadetools.net/tag/measurement'>measurement</a>, <a href='http://www.homemadetools.net/tag/tramming'>tramming</a> </div> </div> </div> </div>
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I do the same thing with a 12" GM truck rotor on my 10 x 54 knee mill for traming

Maybe I should have mentioned that I turn the rotor opposite of your picture and anchor it to the table. The rotor hub is milled true to the brake pad surface so it woks like that as well.

Thanks for the tip. I think I will try that just to test my x-axis ways. I have always thought that the x-axis ran up hill when I move to the right.
The ground surface on the rotor is much smoother than the mill table so that should give good results.
Cheers, JR