# Bench Dog Holes



## TomC (Oct 27, 2008)

I am building a new work bench. Nothing fancy just a 2X4 SYP base and a Birch veneer solid core door top. I want to bore bench dog holes in the top and wondering what is the best method? I would like to use a plunge router to make sure the holes are 90 degrees to the top. The door is 1.75" thick. I have some Rockler bench dogs and the are 0.780" in diameter. Therefore a 3/4" router bit will not work.Does anyone know where I can get an odd size router bit such as 25/32" or maybe 20mm? Also, do I need to bore from the bottom with a backer plate on the top to prevent the birch veneer from splintering?
Thanks Tom


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## woodnthings (Jan 24, 2009)

*Tom why not just use ...*

A block of hardwood say 1 1/2" or 2" with a 13/16" hole bored vertically as a guide. A Forstner bit will bore a clean hole efficiently. I really wouldn't use a router for this project myself.
You want a relatively moderate speed say 1000 or less RPM for that size bit and pull it out often to clear out the chips. :thumbsup: 
I think the bench dog needs a little slop for it to jamb in the hole
so you should be fine. Just curious..what size holes do they recommend? :blink: bill


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## TomC (Oct 27, 2008)

I don't know what size hole they recommend? I bought a bench from them when I could get it at 20% off. The dogs that came with it are the one that are 0.780" in diameter. I just looked at their catalog and the ones they sell say they are for a 3/4" hole. I did bore a 3/4" hole in a piece of wood and the dog will not go in it. I believe the bench is inmported and the holes are more that likely metric.

Tom


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## jlhaslip (Jan 16, 2010)

I have a Maple veneer solid core door as a work bench and when I drilled some dog holes they worked fine until the pressure distorted the holes.
With some luck, the solid core will be a hard wood like Maple, but not likely, in my experience.


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## TomC (Oct 27, 2008)

I don't know what the core is made of but the door weighs a ton.
Tom


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## joek30296 (Dec 16, 2009)

There's a good chance that it's solid particle board with birch veneer faces. That's why it's so heavy.
Just my 2 cents.

joe


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## Hammer1 (Aug 1, 2010)

You should check your bit, the dogs from Rockler and others are made to fit a 3/4" hole. Some are spring loaded. In solid wood workbench tops, the wood can move. If the holes were precise, you may not get the dogs in. The holes are 1/32" larger than the dogs. Solid core doors are filled with particle board. It doesn't drill that cleanly and the holes may degrade with frequent use. Whether you decide to use a router or a drill bit, use a tight fitting backer so the exit doesn't blow out, or drill until the point just comes through and then drill from the opposite face. A trick to keep the drill straight, in addition to a guide block, is to hold it out at arms length, not in close to your body. That way you can see if it's perpendicular much easier.


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## TomC (Oct 27, 2008)

The bench dogs I got from Rockler came with the a work bench. They will not go in a 3/4" hole. They are 1/32" larger than a 3/4" bench dog. I guess I could buy other dogs but the metal dogs at Rockler are about $20+ per pair.
Tom


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## woodnthings (Jan 24, 2009)

*Finding a 20 mm bit is a problem*

I did find this adjustable one with 2 cutters:
http://cgi.ebay.com/NEW-IRWIN-Large...Drill-Bit-/300476416624?pt=LH_DefaultDomain_0
They recommend a drill press, but a slow speed 1/2" drill may work. :blink: I donno.
If not, the closest size drill to 0.780 is 13/16" at 0.8125 like one of these: http://cgi.ebay.com/8PC-COBALT-SILV...-WOOD-BOX-/380278499697?pt=LH_DefaultDomain_0

Just another wild idea would be to line a large size hole with a copper tube epoxied in place and a nice slip fit for your bench dog...don't ask me what size ....It would protect the particle board from distorting possibly?


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## The Engineer (Mar 16, 2010)

A 13/16" (0.8125) quality forstner bit would be available rather easily.
One such source is here: http://www.woodcraft.com/Product/2001917/3151/1316-BORMAX-Forstner-Style-Bit.aspx

Having said that, I bought holdowns for my bench, sized for 3/4" holes. They measure just a hair over 5/8" diameter.
Since you said your bench dogs are a shade over 3/4", at .780", perhaps they would work in 7/8" holes.
On the other hand, perhaps holdowns need a little more slack to wedge into the hole when you knock it down.
I don't have any bench dogs yet, but I was planning to make my own from something like osage orange, or lignum vitae.

Another consideration is the thickness of your door (top). My bench top is built up of 4 layers of 3/4" plywood with a replaceable hardboard top, so my holes are over 3" through.

If the particle board core of your door is a problem with deformation of the holes, perhaps you could attach a 1 1/2" thick strip of oak, or similar material to the bottom of your top, under the holes before you drill them.


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## TomC (Oct 27, 2008)

I bored the bench dog holes in my work bench top today. I went with 3/4" hole because I wanted to use a router to bore the holes. I will just have to make my bench dogs or buy new ones for a 3/4" hole. I had to order a 1" bushing for my router to use in the jig I made. The jig is 1/2" plywood with a 1" hole drilled just over 1/4" deep and a fence to keep it square to the top. I clamp the jig to the top. The router bushing sets in the hole on the jig. When I plunged the first hole I drilled a 3/4" hole the rest of the way through the plywood. Now my jig has a zero clearance plate for the bit. I did not get any chipping of the veneer.
Tom


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## jimmyhopps (Nov 18, 2011)

how is the veneer and door holding up around the bench dogs.


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## omextreme (Nov 18, 2011)

About to do the same thing to my bench, thanks for the insight.


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## railaw (Nov 15, 2011)

*Bench Dogs in Solid Core Door*

I'm considering throwing a door onto my bench top and adding dog holes. Any report on how the door is holding up?


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## TomC (Oct 27, 2008)

railaw said:


> I'm considering throwing a door onto my bench top and adding dog holes. Any report on how the door is holding up?


They are holding up fine. The top is getting rough and needs sanding. I put a finish on it but I have had some glue stuck in spots.
Tom


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## Cliff (Feb 5, 2012)

joek30296 said:


> There's a good chance that it's solid particle board with birch veneer faces. That's why it's so heavy.
> Just my 2 cents.
> 
> joe



This is most probably correct and if so hold down dogs won't work because in MDF or OSB or particle board the dogs will tear the soft inner cores to shreds leaving the veneer to carry the load - which it won't . You would need a solid wood top and bottom sandwiching the door made from 3/4" thick ( or thicker) oak or maple for the dogs to have something against which to bite.


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