Drilling a Long (12") Hole

[museumguy]

A little pricey but will this work? https://truepositiontools.com/products/c...ight-jigs/

[Willyou]

Thanks - all good responses/suggestions. MY DP has a 3" throw and it is only a bench-top! So thinking about it now it would be a very complex process to drill (Not enough room to fit both a 12" drill PLUS the 12" shelf under the bit -  even with the bed lowered all the way). So it would require multiple length bits and steps. Doing it by hand after an initial pilot hole - maybe?!

Of course (or perhaps obviously!) plan "B" is to route a "2-step" dado in the bottom of the shelf and use a filler strip to close off. That seems to me to be the most reliable and least amount of effort overall. Thanks.

Sounds like a plan. Good luck.

[KyleD]

When you get below 1/4 inch with router bits they start to get mighty prone to breaking with any real depth of cut. I have a sliding miter saw with adjustable depth of cut that can be set up to cut dados. This would leave a 1/8" wide dado. Instead of cutting a T shaped dado I would leave it straight 1/8" and sand or hand plane a slight wedge shape in a tight fitting filler piece. Then tap it in with a little glue and plane or sand flush.

[Bill_de]

Depending on how deep the shelf is, could you route a groove along the back edge of the shelf and drill a hole from back to front?

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[Cabinet Monkey]

Lots of long drill bits out there besides the TP one , which works great BTW. 

Colt and Fisch make ‘em too.

[arthropod98]

maybe it's just me, but i think i'd be slightly concerned about losing some strength of the shelf.  of course, this depends on how this shelf is mounted, so may not matter.

i'd be tempted to go from the front then around the side  --  if there's enough cord length.

[Don_M]

A little pricey but will this work?  https://truepositiontools.com/products/c...ight-jigs/

Who knew - I guess there is a tool for everything!

[BrentDH]

Instead of making the groove with two steps, I would just make it one width and then make my "plug" with a very slight angle to it (maybe 1-2*) so that it wedges tightly in the groove as you tap it in.

[iclark]

maybe it's just me, but i think i'd be slightly concerned about losing some strength of the shelf.  of course, this depends on how this shelf is mounted, so may not matter.

i'd be tempted to go from the front then around the side  --  if there's enough cord length.

Concern about the strength or the sag of the shelf seems like a valid concern if the thickness of the shelf is now only 1/4" and the groove is between the shelf supports.

If you are using a saw to cut a groove, it only needs to be deep enough to hold the wire and a thin piece of wood to fill the groove opening.

[Cabinet Monkey]

Concern about the strength or the sag of the shelf seems like a valid concern if the thickness of the shelf is now only 1/4" and the groove is between the shelf supports.

If you are using a saw to cut a groove, it only needs to be deep enough to hold the wire and a thin piece of wood to fill the groove opening.

While it certainly “weakens” the shelf it’s not enough to get concerned about.    The alu LED profile adds some stiffness back to the equation.  

We started doing this 10-15 years ago and have had zero callbacks for “shelf issues” because of lighting grooved into shelving.