Drilling Dog holes Tip

[Prashun Patel]

I've struggled for a couple years on an economical way to drill bench dog holes.

My forstner gives the cleanest and tightest results, but doesn't do well on thick tops.

I never got tight results with a spade bit; which makes holdfasts tricky for me to set.

I stumbled on this method and it works very well for me:

1. Drill with a 3/4" forstner bit down 1/2"; enough to start the hole.
2. Switch to a 1/2" twist or brad point bit, and drill through the bench.
3. Switch back to the 3/4" forstner and widen the hole. The clearance hole prevents heat and chip build up, and keeps the bit cutting cool and efficiently.

Quick, tight, effortness.

[Michael Stein]

This may be a stupid question, but I am fairly new and do not have a bench with dog holes (yet), but how do you ensure the holes stay/are vertical, and not drilled at an angle?

[Prashun Patel]

I find my forstner bit and a hand held drill stay vertical 'enough'. My bench is only 2.25" thick, so maybe it matters on a thicker top, but eyeballing it works fine.

[Bill McNiel]

Nice tip Prashun, thank you.

[Peter Kelly]

Also this: http://www.leevalley.com/US/Wood/page.aspx?p=72602&cat=1,41637


https://www.youtube.com/watch?t=10&v=tnrBZjPT9y0

[glenn bradley]

On my last couple of surfaces that had dog holes I vowed to cure the non-perpendicular issue. These were pretty thick surfaces and so the problem of crooked holes can get amplified by their length. Like Patel I use a staged method. I drill with the 3/4" Forstner for 1/8" or so. I then use the Forstners center dimple and drill down the center with a 7/16" twist drill . . . I am able to stay vertical enough to do this free hand. This eliminates a lot of the spoil and makes the plunge routing go very quickly.

Use a backer:

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I then use a plunge router and a 3/4" spiral bit to drill as far as I can (but not through the other side).

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Lastly, I flip the top and clean up the bottom of the holes with a 3/8" flush bit in a small router.

I use a similar method with a template. Once the first set of holes are done, dogs register the template for the next set and so on. This example also has slots as it is an assembly/clamping surface.

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Definitely more involved than an auger and a brace but, I had reached my limit with non-perpendicular holes. Your use of the holes will directly affect your tolerance for what is good enough. If they're working for you, they're perfect :).

[Reinis Kanders]

As it happens I drilled some dog holes last night. I have settled on using LV brad point drill bit using guide bushing from the above post to drill the first two inches or so and I finish by hand with auger bit from wood owl. Works very well.

Another bit that works well in the power drill is wood owl overdrive bit http://www.amazon.com/WoodOwl-00705-Overdrive-Cordless-Diameter/dp/B004IJTZ50
Overdrive bit actually cuts better than LV brad point bit. I sometimes end up reaming with a 49/64 bit to make bench dogs slide a bit easier.

[Peter Aeschliman]

Also this: http://www.leevalley.com/US/Wood/page.aspx?p=72602&cat=1,41637


https://www.youtube.com/watch?t=10&v=tnrBZjPT9y0

This is awesome! Thanks for posting that. Didn't know that product existed.

[David Eisenhauer]

I marked my hole locations with a penciled "x", then 1) used a hand drill equipped with one of those drill press converters attached to the drill to drill out 3/8" holes with a spade bit, 2) Used my plunge router with a 3/4" straight bit to establish the perpendicular hole (it does not plunge all the way through). The plunge router base was held in position by a straight edge/jig gizmo 3) Went back to the hand drill equipped with a 3/4" brad point to drill all the way through. The initial 3/8" spade bit clears the hole out an amount that causes lots less work/heat for the dado bit and the brad point both, plus the plunged router hole seemed to result in a perpendicular start that was followed by the 3/4" bit. I always envisioned using a longer 3/4" up cut spiral bit, but found them cost prohibitive at the time and I always wanted to follow up with the 49/64" or so sized bit but those aren't as readily available for walk-in pickup at the local store, so I had to reduce the diameter of my dowel stock slightly. I have perpendicular holes without having to purchase extra items, as I have had the drill press converter mounted to an old corded hand drill for years.

[Chris Parks]

A few methods here https://www.youtube.com/results?search_query=workbench+dog+holes

[Paul Wunder]

Prashun,

Thank you for your excellent (and cost effective) tip. Lee Valley has a jig that will help others drill vertical holes. I purchased a non LV look alike about 20 years ago and I have used it multiple times; most recently when I used Confirmats to assemble a cabinet

http://www.leevalley.com/US/wood/page.aspx?p=73237&cat=1,180,42311