Replies

1. 
   mwenz | Feb 21, 2007 10:15am | #1

   Starting with the router and finishing with a bit is probably the most accurate.

   Personally I just bore them with a bit and brace. They don't have to be absolutely perfect.

   Take care, Mike

2. 
   chabber | Feb 21, 2007 10:17am | #2

   Jeff, what kind of wood is the bench top made from? I recently built a bench and the top was made from MDF with a hardboard skin. I attempted to drill the dog holes with a forstner bit, but it quickly clogged. If I took the cut real slow and removed the bit from the hole often, it did ok. It would have taken a while. I then switched to using a wood auger bit and cut the holes in no time flat. I wasn't super worried about being square in that the dogs I got from Lee Valley had a 2 degree tilt built in.

   Granted, the holes are a little rough inside and you have to watch out for splintering when the auger bit comes out the other side. You could start the holes with the router bit and then finish with the auger bit.

   Also, I did all of this drilling with a portable drill guide.

   good luck

1. 
   jeff100 | Feb 21, 2007 10:28am | #3

   Bench top is 85% bigleaf maple, and 15% red oak. Bigleaf maple is native to western Washington state and I think it's considered a 'soft' maple. Soft is a relative term though....it's still a hardwood.Jeff

1. 
   cadiddlehopper | Feb 21, 2007 04:10pm | #4

   Here is how I did it: Bored 3/4-inch pilot hole in a scrap 10/4 hardwood (8/4 should do, too) using Forstner bit. Punched centers for dog holes on bench top. Placed Forstner bit point in dimple to center the pilot hole thru the piece of hardwood which I then clamped down. Using 1/2-inch 110-v drill motor, bored hole thru pilot hole and thru bench top using Harbor Freight Silver & Deming bit (Because it was long and was guided for a greater length). This is not a HF commercial, but that bit cut thru as if the bench top were warm butter. I never expected such performance. The hole is a tight 3/4-inch diameter. This method is very simple and as accurate as one needs. Good luck!Cadiddlehopper

3. 
   Lataxe | Feb 21, 2007 05:05pm | #5

   Jeff,

   Please have a look at the photos in 33837.25.

   I bored 3/4 inch dogholes in my 3 ins thick hard maple bench with three methods:

   1) sawtooth forstner in a handheld electric drill, kept vertical with one of those "drillpress" frames you can mount a drill in.

   2) Same arrangement but with a spade bit having long, sharp wingtips.

   3) Using a brace with an auger, as in the picture in 33837.25.

   The first two methods drill perfectly vertical holes but tend to cause a little breakout on the bottom.  This is mostly because of the lack of "feel" coming back through the electric drill in its cage.  You press hard right until the beakthrough, as you have no feedback when the bit is about the exit the bottom of the bench top. 

   The breakout is minimal and anyway can't be seen and doesn't affect the grip on dogs or hold-downs.  But I soon switched to method 3, to get that feedback.

   Method 3 is slower and requires careful use of an adjacent square to start and keep the bit vertical.  However, it gives the most feel and you can avoid any breakout at all. You could begin the vertical hole with the caged drill/forstner-spadebit method then switch to the brace & bit, which will tend to be kept vertical by the hole-so-far. 

   If you use a bit with a slow-screw tip and long, sharp wings then no breakout occurs, if you note the feedback of imminent breakthrough and are careful when the tip-then-wings exit. 

   You can make doubly sure that there's no breakout if you feel for the bit's screw tip-only exiting (it comes through first) then use the hole to align the bit from underneath, to get the last millimetre or two of wood out the bottom of the hole.  To do this, you need to have room under the bench to get the brace and bit in.

   Lataxe

4. 
   Walnutz | Feb 22, 2007 03:08am | #6

   Jeff

   2 ways to combat breakout of the bottom of your bench. 

   1. Start your hole, then use a skinny bit to go all the way through, which gives you a pilot hole.  Then, using that pilot hole, drill up from the bottom, eliminating any tearout.
   2. This is what I did.  Clamp a piece of scrap to the bottom of your bench underneath where the holes are.  The scrap will absorb the tearout, and the exit hole will be clean.

   By the way, your bench dogs will work just fine without worrying about being exactly perpindicular.

   Walnutz

1. 
   user-153029 | Feb 22, 2007 12:57pm | #7

   I used my new Triton drill to put 3/4" holes in a mdf top to match up the holes on my maple workbench and it worked great.  The Triton is like a portable drill press.

   Edited 2/22/2007 5:00 am ET by Tim Malone

5. 
   MonteB | Feb 22, 2007 06:24pm | #8

   Jeff,

   As I understand it, 2-4 degrees of tilt towards the tail vise / end vise is an advantage.

   Monte

1. 
   jeff100 | Feb 22, 2007 08:22pm | #9

   Thanks. That's my understanding as well. I will achieve that via an angle on the face of the dog....WOOF.Jeff

2. 
   mike4244 | Feb 23, 2007 05:07am | #10

   Youre correct, I use about 2° on hardwood benches, up to 5° on softwood benches.The angle doesn't have to be exact,just so the dog tilts a bit towards the vice.If the holes are bored straight the stock between the dog and vice has a tendency to raise off the table at the dog end when snugging up the vice.Softwood bench holes will elongate a bit over time without an insert like black pipe pieces.Thats why the angle is a bit more on these benches.Use a spade bit with a stop collar or a piece of tape for depth. These bits will give you a small center hole when you break thru.Then bore the last 1/4" from the underside.

   mike

6. 
   MikeHennessy | Feb 23, 2007 03:32pm | #11

   A 3/4" Forstner bit will be fine, and it doesn't have to be absolutely, perfectly square. I just drilled mine freehand with a regular drill.  Hey -- it's a workbench, not a watch! ;-) If you're worried about blow-out on the bottom (tho' I can't imagine why anyone would be), just fix a sacrificial piece to the bottom before drilling. As another poster said, go with the Veritas dogs/pups -- they have a tilted face built in. Also, you can't beat the Veritas hold-down. Check it out:
   http://www.leevalley.com/wood/page.aspx?c=2&p=31149&cat=1,41637

   I also have a Veritas Wonder Dog that often comes in handy.

   Mike Hennessy
   Pittsburgh, PA

7. 
   thewoodshepherd | Feb 23, 2007 07:30pm | #12

   I like the idea of perpendicular holes, so I chose to start them with a plunge router and the 3/4" bit.  Then I finished with the technique of drilling through with a small pilot bit, then starting from the underside, drill up through with a 3/4" bit to lesson break down of the hole on the bottom, then flipping the benchtop over to finish with the same 3/4" spade bit in a hand held drill from the top.  Works great.  Be ceftain to use a guide of some sort to keep your holes in good alignment as you go down the length of your bench.

   the woodshepherd

   SE Ontario, Canada

1. 
   Handrubbed | Feb 24, 2007 11:51pm | #14

   There are some good tecniques here, but one of them is not the way to go, and that's using a forstner bit.  I learned the hard way on a brand new bench top.  A forstner is a steerable bit and that is why electricians use them to make crooky holes with a hand drill.  A forstner in a drill press or drill guide makes a very clean straight hole.  Of course the bench top is not going to work in the drill press.  What I will do next time is use the plunge router to start the hole to its max depth, then finish with a brace and bit or a spade bit with something clamped to prevent the breakthrough.  I don't see how a counterbored hole with a small diameter helps though.  By the way, my bench top came out fine with a just the first hole being problematic.  I filled and rebored it.

   By the way a small chamfer on the dog hole done with a 45 degree router bit is a nice finishing touch.

1. 
   jeff100 | Mar 03, 2007 01:01pm | #15

   ...one of them is not the way to go, and that's using a forstner bit...

   Not to disagree, but I will, with a caveat of course.  While I agree that forstner bits can and do 'wander' if allowed to (yes, it's happened to me), it's just a matter of proper technique and tools.

   To bore out my dog holes, I did end up using a forstner bit.  But I used the forstner bit with a "JIG IT" drill guide from Rockler.  The drill guide is a funnel shaped guide and I bought a long shanked carbide forstner bit from Rockler as well, to drill my dog holes by hand.  Using a hand drill, and the JIG IT guide, I've had excellent results, in fact, spectacular results.  Taking care and slowing down when I'm near the bottom of the benchtop with the forstner bit, I don't even get any tearing out or splintering on breakout.  I was reluctant to buy the drill guide, but it's proven itself well, and I now view it as money well spent.  Here is a link to the guide. 

   http://www.rockler.com/product.cfm?page=2406

   Another justification for talking myself into buying the drill guide, is that the JIG IT guide is the same drill guide used with Rockler's hinge cup hole forstner bits for boring out cabinets doors for European style hidden hinges...which I plan to use frequently in my cabinets.

   Best regards, Jeff

1. 
   Handrubbed | Mar 03, 2007 08:56pm | #16

   That's a good solution, one that I would have chosen myself; but as you say there is a caveat that one is willing to add $30.00 of expense to this end.   The fostner bit, as well as some other types of drill bits is meant to be used with some form of mechanical guidance, be it a drill press or drill guide.

1. 
   tmoney | Mar 12, 2007 05:06am | #17

   As a high school woodworking teacher, I have installed vises and dog holes to seven benches ( 2 1/4" maple) with four vices each.  A  3/4" spade bit worked better than  more expensive carbide tipped forstener style bits.  Steel bench dogs are best, shopmade wooden dogs are better than the plastic ones from Rockler.

8. 
   [email protected] | Feb 24, 2007 07:09am | #13

   Start the holes with the 3/4 plunge cutting straight bit,  as deep as you can get it. 

   Then switch to a 3/8-inch pattern bit, and use the hole you cut as the guide to punch it on down through the bottom.