21/32 x1/4 drill / transfer punch guide

My life as become a never ending battle to make enough special tools or fixtures for a project I am working on
the latest is this guide fo r drilling or using a transfer punch to locate the center of a pre existing hole.
I started with a 20mm 10.9 grade bolt mostly because the root diameter of the threads was close enough for my purpose of locating the center of several 21/32" holes that are drilled in a 1" thick plate clamped to the structure of the machine I am building.
Attachment 19374 Attachment 19375 Attachment 19376

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Thanks Frank S! We've added your Punch Guide to our Metalworking category,
as well as to your builder page: Frank S's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="http://www.homemadetools.net/homemade-punch-guide"> <img src="/uploads/204180/homemade-punch-guide.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-punch-guide">Punch Guide</a> <span> by <a href="http://www.homemadetools.net/builder/Frank+S">Frank S</a></span> </div> <div class="tags">tags: <a href='http://www.homemadetools.net/tag/punch'>punch</a>, <a href='http://www.homemadetools.net/tag/guide'>guide</a> </div> </div> </div> </div>
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I like this idea for many different reasons and uses. On those days when you want to go out in the shop but don't want to get too deep in a big project just make one of these on the lathe. A bit of preplanning will set you up to build an entire set of various sizes, threaded and plain that will fit on a small wood block or in a small box. Color code them to identify specific sizes and/or threads. If you want to get really sexy make them with coolant feed holes. Even a small angle chamfer on the top of the hole will work that way. A longer thread on the inside to make room for a locking nut will improve centering as the locknut will take up the slack between the threads which allows a few mils of misalignment if the purpose of the tool is to spot the visible end of a broken bolt needing removal.

THanks Ed also find my thread http://www.homemadetools.net/forum/t...5-8-11-a-63210 the locking nut is there just for the same reason you stated I didn't bother adding the chamfer on that one since I drilled it from the threaded end for coolant when using a hand drill as I did in these operations I just pull out and dip in thread cutting oil
Yes making a set is one of the to do lists it would take a while to be sure since I would want the smooth sizes for each 1/64" through 2" bore size
the threaded ones would be fewer however if started with 1/4-20 through 1 1/2 6 for NC plus the NF and all of the 12 TPI sizes from 3/4 through 1 /12 " would be quite a large number the I would want metric as well. by the time I would have a complete set it could easily number a 150 or more, easily turning into a major project of it's own. NOPE! I'll probably just make one as needed when needed