Ideal drill bit for entrance holes (1 Viewer)

[Pilotone78]

Hello. First post here. My daughter and I are going to be making a bunch of nest boxes with some leftover cedar I have. Bluebird & chickadee.

Question for you all - do you prefer to use hole saws, spade bits or forstner bits? I have a drill press. My thought was to use a forstner, but before I go out and buy those sizes I figured ask.

Thanks!

 

[Andy Adcock]

Hole saw, every time but have to admit, never tried the others.

 

[Mike Crawley]

It’s ages since I’ve been involved in making nest boxes but I used (actually the carpenter I was helping provided) spade drill bits.
I guess that the birds really don’t care, it’s what is convenient for you and your tool kit

 

[Dan Miller]

Whatever kind of drill that makes the properly sized hole. It's not fine cabinetry, and the as Mike says above, the birds don't care.

 

[Kits]

Welcome to Birdforum. I hope you enjoy your visits and good luck with the nest box making.

 

[S_Man]

Easiest way for me was hole saws.
Recently the main issue is to protect the wood around the hole to prevent woodpeckers to destroy nests.

 

[Torchepot]

Have all three and would choose holesaw every time, though I guess at least if you use either of the other two you don't need to winkle the cut bit of wood out of the saw each time.

If woodpeckers enlarging the holes is an issue there are stainless steel plates with different size holes available or you can cut a piece of slate to approx 90mm square, drill a hole in each corner for fixing screws and make an entrance hole with a cheap diamond hole saw, slate is really soft so the saws last for ever. I've made several like this and they look a bit more rustic than the shiny steel ones.

 

[Pilotone78]

Thanks all. I have copper hole guards. I understand that all will technically work. 1.5” is a size that’s slightly large for a spade or forstner but on the smaller end for a hole saw. I also dont have that size in any of my bit or hole saw collection, so figured if I have to buy one might as well get the one that works best.

 

[Torchepot]

I guess the forster bit will make the neatest hole and because there's no need to remove the plug, as with the holesaw, would probably be the quickest.

Not seen the copper hole guards - sounds like a good idea - I bet squirrels don't like the taste and slugs won't cross it either

P.S. Isn't 1.5" a bit big for chickadees?

 

[Elkhornsun]

The least efficient are the bi-metal hole saws. Instead of a spade bit I would recommend a auger style bit. This is hybrid of a standard wood auger bit and a self-feed type of drill bit. It has a threaded tip to pull the auger cutting section into the wood. A Forstner is best used with a drill press and good for cabinet makers with thinner boards being used.

https://www.amazon.com/IRWIN-SPEEDBOR-2-Inch-6-Inch-3041021/dp/B003KGBIX4/ref=sr_1_6?crid=157FMPP3VGVIE&keywords=IRWIN+SPEEDBOR+Drill+Bit&qid=1705779159&sprefix=irwin+speedbor+drill+bit%2Caps%2C173&sr=8-6

 

[Pilotone78]

I guess the forster bit will make the neatest hole and because there's no need to remove the plug, as with the holesaw, would probably be the quickest.

Not seen the copper hole guards - sounds like a good idea - I bet squirrels don't like the taste and slugs won't cross it either

P.S. Isn't 1.5" a bit big for chickadees?

Yes 1.5 is too large for chickadees. The right size for bluebirds. I’m building both. Copper hole guards are great and they are like $3. Check online there are a few dealers. My local Audubon shop carries them. They look nice too!

 

[MiddleRiver]

THe trick with drilling these holes is to clamp the 'finish' piece to a sacrificial scrap of lumber. This'll prevent tear out on exit side.

 

[dantheman]

THe trick with drilling these holes is to clamp the 'finish' piece to a sacrificial scrap of lumber. This'll prevent tear out on exit side.

Yes - that augurs well for a smart finish.

 

[Torchepot]

Those Irwin speedbor bits really bite, great for chewing through joists when running cables or pipework, but a bit too aggressive for cutting a few holes in bird boxes in my opinion, especially when using a drill press.

A nice project to do with your daughter by the way, when I was a kid I really wanted a bird table and my dad (a carpenter) and I made one together, it helped to kindle my interest in carpentry.

 

[Elkhornsun]

How "aggressive a wood bit depends on the rpms and the feed speed of the operator. A self-feed bit is far more likely to chew up the wood which is why they tend to be used where the hole is out of view. A bi-metal hole saw will take 5 times as long when you add in time it takes to remove the plug from one hole before you can start the next hole. The one exception are the TCT Blue Boar hole cutters that have large teeth that extend past the inner and outer wall of the hole cutter so the cut plug will fall out.

 

[Pilotone78]

I decided to go with the forstner bit. $20 Freud at the local HD. Those speed bore bits are really dangerous in a drill press. They will throw the wood right at you. Not designed for high RPMs. Will report back, but I think it’s going to be the way to go as they cut very clean.

 

[Torchepot]

Just talking from experience, when I first used those Irwin bits they grabbed the wood so hard that they nearly sprained my wrist, I've also split smallish bits of wood with them as they want to pull through the wood so fast. I'd never use one in my drill press. Sometimes faster isn't necessarily better

Sorry, crossed post with Pilotone.

P.S. A useful tip for avoiding the plug getting stuck in the holesaw is to flip it over before it's all the way through and finish it off from the other side. Not much use with very thin material but works OK with most thicker stuff.

 

[etudiant]

Yes 1.5 is too large for chickadees. The right size for bluebirds. I’m building both. Copper hole guards are great and they are like $3. Check online there are a few dealers. My local Audubon shop carries them. They look nice too!

A hole 1.5" in diameter does keep out starlings, but is a welcome mat for house sparrows eager to take over the box.
They do kill nestlings as well as adults in the box.

There are lots of Bluebird support sites, best known is Sialis Home - Helping Bluebirds and Other Small Cavity Nesters Survive and Thrive
For sparrow removal, the Van Ert trap is very effective Van Ert Enterprises
Alternatively, a narrower 2"x1 3/8" oval nest hole appears preferred by bluebirds and dislikes by sparrows Out My Backdoor: What's the Best Bluebird Box Design? | Department Of Natural Resources Division

Good luck to your daughter and you with your Bluebird nest box project. They are just delightful birds to have around.

 

[Pilotone78]

We are on the edge of bluebird territory so will be interesting to see if we even get any action. No shortage of house sparrows though! Thanks for the resources. I’ll check them out.