Undercut slot cut with a 1/8" T-slot bit. Center area removed and back curved edge cut with a 3/16" end mill.  Friction tape added for a nice snug friction fit of the ruler.

   

Small scrap of Bubinga that needed a use. Ruler/T-Square to be added to a drawing kit box I'm working on. 

One more scrap saved from the trash bin. 😉

4D

Realized that since the ruler can slide through it could be used as a marking gauge. 

Cut a recess for a small square nut under the friction tape and added a thumb screw so the ruler could be locked in place for critical needs. 

Doubled the uses for it with just a little more CNC work. Last step will be to cut the threads on the thumb screw shorter. 

4D

Heckuva a cool idea!

Hey 4D, what do you think of the open top area, the channel tabs for lack of a better word, those look kind of thin? Could they snap or split when the screw is tightened?

8 minutes ago, John Morris said:

Heckuva a cool idea!

Hey 4D, what do you think of the open top area, the channel tabs for lack of a better word, those look kind of thin? Could they snap or split when the screw is tightened?

With the friction tape under the ruler, it only takes a 1/4 turn or so to lock it in place.  Top had to be open to cut the slots, and I didn't want to lower the slot  for a thicker lip as the nut below is 1/8" thick thick only leaves 1/16" of wood under the nut.

The nice thing about making this myself is that if it does fail any way I'll learn from that failure and can make another one a bit thicker.   The thickness of this one was dictated by the thickness of the bubinga scrap.   I could have made it thinner but not thicker.  😉

4D

Sweet! Bubinga is pretty hard and with interlaced grain. Should hold up well.

26 minutes ago, 4DThinker said:

With the friction tape under the ruler, it only takes a 1/4 turn or so to lock it in place. 

That's the ticket! Just a light turn locks it in, I had not thought that it would only be a gentle twist, I had in my head that'd I'd be wrenching it down, but you are right, don't take much to lock it in place. Thanks 4D