locating pin for drilling a linear series of holes

I really dislike repetitive measuring when there is a way around it.
For drilling a series of holes in a straight line on my mill or in a drill press for that matter I like to make a stud pin hole locator.
For my T nut project what I did was machined off the head of a 1/2" bolt then turned the OD of the end of it down to match the ID of the holes in this case 27/64s
Attachment 42171
Attachment 42172
Loosely mount it in the table slot
Attachment 42173
Center the drill chuck over it snug up the chuck and tighten the stud pin in the table loosen off the chuck and shift the table the proscribed distance to where the next hole would be lock down the table and start drilling
Attachment 42174
Advancing the bar one hole at a time the standoffs position the bar in the Y plane while the pin stud positions in in the X plane until I have advanced as far as I can still clamp the bar
Attachment 42175
Then I remove the stud pin flip the bar around use the drill bit to locate the last hole drilled re locate the stud pin under a hole in the opposite end of the bar then drill the remaining holes
Attachment 42176
Attachment 42177
Attachment 42178

<!-- BEGIN /var/www/html/homemadetools/protected/modules/zeus/views/tool/postUpdate.php -->
Thanks Frank S! We've added your Drill Press Hole Locating Pin to our Drilling and Drill Presses 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="https://www.homemadetools.net/homemade-drill-press-hole-locating-pin"> <img src="/uploads/254010/homemade-drill-press-hole-locating-pin.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="https://www.homemadetools.net/homemade-drill-press-hole-locating-pin">Drill Press Hole Locating Pin</a> <span> by <a href="https://www.homemadetools.net/builder/Frank+S">Frank S</a></span> </div> <div class="tags">tags: <a href='https://www.homemadetools.net/tag/drilling'>drilling</a> </div> </div> </div> </div>
<!-- END /var/www/html/homemadetools/protected/modules/zeus/views/tool/postUpdate.php -->

With the las picture it looks like you are setting the hole center by eye.

Still it is a good project.

Ralph

Quote:

---

Originally Posted by Ralphxyz

With the las picture it looks like you are setting the hole center by eye.

Still it is a good project.

Ralph

---

There were a couple holes that drifted off center a bit. Actually I shouldn't be using 1/2" studs on T nuts that fit in a .560 slot. Should be using 7/16" studs or use only T bolts. I could mill the slots out to be standard with the rest of my machines but the mill is fairly old and has an unmolested table

Just days ago, a post demonstrated a very labor intensive manufacture of T-nuts, and resulting in a very small quantity, far less than half what Frank S will get here.
Using a spacer pin (indexing) is efficient reusable tooling. With the spacing allowing for saw cut, those holes can index the cut-off just as well.
To keep the edge distance consistent, add a bar (longer than part) to contact and slide against for each successive position. Even in a plain drill press (where there is no defined X movement) the spacing will be so regular, detecting any variance by eye will be difficult.

A good method. Almost looked like you were drilling shelf pin holes until I enlarged the pictures. A great method to make a lot of T nuts in a hurry. Or any other indexed series of holes. Now that you have the T nuts you should have any slop on the pin idea.

Quote:

---

Originally Posted by mwmkravchenko

A good method. Almost looked like you were drilling shelf pin holes until I enlarged the pictures. A great method to make a lot of T nuts in a hurry. Or any other indexed series of holes. Now that you have the T nuts you should have any slop on the pin idea.

---

I usually find ways to get more mileage out of several of my special tools I can always make some sleeve bushings to fit over the pin for drilling larger diameter hole series just as I can make more strand offs to use on my tramming posts on the riser blocks, for the most part my jobs do not require critical measurements to the inth decimal so a few thou one way or the other is not a deal breaker. I particularly like being able to measure once then drill and advance without having to measure or layout and center punch the hole series. To speed things up even more I can make a pair of over center cam lock or toggle clamps

Simple and elegant. You can opt to use a fence.:hattip: