Thread: best type of drill bit for dog holes?

I used a flat bit for mine, pretty sure it left a clean face

I'd just use a speedbore....a brand new flat bit,,,with spurs on the side, for crisp cut. There's a new 3 flute irwin (blue thing) out that cuts nicely I've noticed. At work we've got one.

And clamp onto the underside of the bench (where your worried about that tearout) some scrap, so the tearouts in the scrap. Setup a couple of squares to guide yourself with. Maybe with a mate to guide you vertical from the side you can't see from, so you don't have to change stance to check etc. Make sure the scraps tight at the hole. So have a clamp right next to it. some ideas.

But if I was you.......just quietly......don't worry about damaging your bench. The sooner it gets damaged the sooner you'll feel inclined to screw jigs to it. Its very handy being able to just pick up the cordless and screw jigs etc straight down flush whereever you want......you can't be practical and do things like that if your worried about even scratching your new workbench.

I am no expert but can't you use a spadebit?
Wolffie

spadebit = speedbore samething AFAIK

Originally Posted by Wolffie

I am no expert but can't you use a spadebit?
Wolffie

yes you could, spadebits (or flatbits as other posters have referred to them) are designed for rough cutting wood, however I've found that they tend to wander off course drillling deeper holes. Plus they have a tendency for tearout at the start and at the end of the hole. I think that's why they
aren't included in Veritas' recommendations.
Happy to stand corrected if others have found them reliable for drilling dogholes.

Irwin speed bores are a type of auger bit AFAICT that look useful, but I've never seen any in 19mm/3/4" or 1 1/2". they only seem to be available in very limited sizes.

Personally I'd go the Forstners.

I have been wondering the same thing as I have finally decided to go with round dog holes in my bench (unless someone wants to come visit me with their Domino).

I was contimplating buying a new router bit and using the router to plunge the holes square, would this work?

flat bits are fine. In fact I think their ideal, because their cheap, and you can docter them.

Took some photos. Show you what I mean.

By chance I had chance to use one this arvo. I making a jig for my lathe. And I need a tight fitting hole on the 5/8" spindle. Ultimately thats all that matters.

pic 1 - Just found an old one from the box thats a bit oversize. and just grind it down slowly until you get a good fit. Just grind the wings equally. Count to 3 on one side, or when your fingers get too hot, or whatever then do the other side the same way.

Drilled a hole in the scrap......checked its fit over the actual spindle. Still too loose. Ground a bit more, drilled a hole, checked again.....take your time and keep doing that so you don't grind too much until you get the fit your after (for your dog holes I'd imagine you want a sliding fit)

pic 2 - can see all my attempts. 4th time I got it spot on.

Now, because these things are so cheap, you can put that aside, named it ' for spindle holes' so I know what it is for, and never change it again. For spindle holes only .

pic 3, 4 - When I built this bench about 8 years ago, I tried these veritas dogs too, because everyone was raving about them. And heres the bit I used. And really haven't used it since . Dog holes still there but I never used them. Found I don't like round dogs. spinning problems (especially those pup things) I found better methods I thought. Not something you probably want to hear

You might have convinced me to change my stubborn mind apricotripper.

there is a thread linked at the bottom of the page called 'what type of drill bit' that discusses the same topic.

I have to say I'm not convinced by spade bits, I don't think that they provide the level of control needed. I'm favouring the forstner for the 1 1/2" hole and I think I'll use a 3/4" auger bit for the dog holes. I wish I knew more about drill bits!

how about a clean cut bit.

we use them for fencing can be got in sizes from 1/4" up to 2".

also known as clean cut auger bits.

I would not use a spade bit as a first chioce as the hole will not be perfect and regular.

a traditional forstener bit seems like a good idea and may be in some of the softer northern hemisphere timbers but will be slow going and frequent sharpening in ausie hardwood....... you will also find the forsteners when they get that small tend not to clear their chips particularly well especialyu straight out of the box.

a carbide tipped boreing bit, similar to a forstener would be possibly one of the best two choices, they cut true and follow there own hole as well as a forstener andcut a very nice clean hole.... with plenty of staying power in hardwoods.

the other of the two best chioces in my opinion would be a carbide tipped brad point bit.... but in 3/4 it will start to be expensive.....it will perform better in deeper holes.

a auger also is not as percise a bit as the two best chioces above and again is at a disadvantage in hard woods.

with any of the non carbide bits you will need to keep the speed down unless you want to send smoke signals and blunt the bit quickly.

to get the holes square & true the best option is to mount up an electric hand drill in one of those accessory drill press things and swing the drilling axis off the base...clamp the base down for stability.

when I drilled my do holes (which by the way I very rarely use.. I could easily live without them), I started with a spade bit because at the time I had nothing better.
I found the holes were not true and undersized.
so
I had at them with a freshly sharpened hole saw, that I knew cutt the true size.
The holes in my bench are nowhere as clean as they would be if they were cut with one of the better choices.

cheers

If you have one, a brace and sharpened auger bit would do a nice job. Line up the bit with a couple of try squares. Practice on some scrap first, of course.

Drilled my dog holes a month or so ago. Used a new augur bit which I bought at one of the bargain tool stalls at the Wood Show last year. Very clean, smooth and very quick. My bench top's made from 65mm thick tassie oak. The bit went through like a hot knife through butter. I was very pleasantly surprised. No tear out as long as you have a backer block.

To get the holes vertical (although some people say they should be at a slight angle), I used the drill press to drill two guide holes at my desired spacing through a hardwood block about 75mm thick, then clamped the block in position on the bench top and away you go. That way, each hole is exactly the same distance apart from the next one. If you want the hole at a slight angle, just drill the hole in your guide block at that angle.

Lots of guys here say use a spade bit. Probably OK but from using spade bits in framing previously, I was concerned they might be a bit rough. I found that my spade bits tend to "shudder" a bit when the spade part engages the timber but maybe they weren't the sharpest they could have been. I thought of using a router or forstner bit but the augur bit's just fine.

Have used the Veritas bench dogs with no problems. The flat face on them tends to force them square to the face of the workpiece but it could depend on the tightness of the fit in the dog hole. If the dog is a tight fit, it can resist squaring up to the workpiece. Maybe that's what apricotripper was referring to.

I do get a bit nervous using the metal dogs just in case I nick my plane blade on them. Have thought about making hardwood dogs but haven't got around to it yet.

Hope this helps. Cheers
Samson