Hole diameter gage

Before I broke down and bought a set of pin gages, I made this tool for measuring the diameter of holes too small for split-ball gages.

https://s3-us-west-1.amazonaws.com/f...he/35511-1.jpg

It consists of two parts: a housing with a lock screw and a tapered measuring gage with a cut away section that, in concert with the lock screw, prevents the measuring rod from falling out and damaging the slightly fragile tapered rod.

https://s3-us-west-1.amazonaws.com/f...he/35511-2.jpg

In use, the tool is calibrated by sliding the taper into a hole of known diameter and measuring the projection of the rod from the top of the body. With this reference point it's then just a simple bit of math to obtain the diameter of an unknown hole.

Yes, I knew full well when I made it that it could be fooled by a bell-mouthed hole. It was only used for non-critical measurements. I knew that I would eventually buy pin gages and I did.

Great idea !
Thanks for sharing !
Christophe

Thanks mklotz! I've added your Hole Diameter Gauge to our Measuring and Marking category, as well as to your builder page: mklotz's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/hole-diameter-gauge"><img src="http://www.homemadetools.net/uploads/128102/hole-diameter-gauge.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/hole-diameter-gauge">Hole Diameter Gauge</a> <span> by <a href="/builder/mklotz_3">mklotz</a></span> </div> <div class="tags">tags: <a href="http://www.homemadetools.net/tag/gauge">gauge</a>, <a href="http://www.homemadetools.net/tag/measurement">measurement</a>, <a href="http://www.homemadetools.net/tag/hole">hole</a></div> </div> </div> </div>