small metric forstner bits

[herb fellows]

I'm looking for metric forstner bits in small sizes. 6mm to 14 mm. Imperial 'equivalents' wont do, needs to be very precise for the project I have in mind.
I've seen sets that start with 6mm, but very little after that. I would prefer 6,7,8,9,10, 11,12,13,and 14.

Does anyone know where I can find smaller sizes like this? I've tried hobby stores, no luck so far.

[LCHIEN]

Lee Valley has metric bits.

They have 10-35 mm bits in both HSS and HCS (following link is for HSS).

http://www.leevalley.com/wood/page.aspx?c=2&p=63566&cat=1,180,42240

Doesn't go below 10 mm, though, in Forstner, but they do have HSS and HCS brad point bits from 3 mm up to 10 mm.
If you can stand to sub a brad point for a small forstner...

[phi1l]

ya, I think what you are looking for are brad point bits.

I just Googled : "metric brad point drill bits" & got tons of hits.

[cabinetman]

This set starts at 6 mm but doesn't have your entire sequence.
.

[herb fellows]

How much of a flat bottom am I going to get with brad point bits? That's sort of important for what I'm doing, that's why I wanted the forstner bits, but they don't seem to exist.

[LCHIEN]

How much of a flat bottom am I going to get with brad point bits? That's sort of important for what I'm doing, that's why I wanted the forstner bits, but they don't seem to exist.

Both the brad point and the forstner will have a point in the middle.
The brad point will have a spur on the outside, so will the forstner to a small degree.
So those parts are not completely flat. The part between the outer spur and the center point is vanishling small under 10 mm, less than 3/16." I would say its more or less but not perfectly flat. How flat does it have to be? I would say they're closer to flat than a regular 118° drill bit.

surely you have some imperial (inch fractions) brad points available - to me that's the woodworker's bit... pick a 1/4" to 3/8" one and drill it and see if its flat enough for you.

you got me curious, maybe tomorrow nite i'll drill some 1/4 and 3/8 and 1/2" forstner and brad point holes partway thru a piece of wood and then section the holes in half with the table saw.

[herb fellows]

I guess I'm just getting lazy (er?). Instead of doing it and looking at it, I just went with the maxim that flat bottomed holes are only attainable with fostner bits.

I'm inserting gems and other bits and pieces into the wood, I'm working on some jewelry pieces I dreamed up. I want the inserts to look perfect, and a lot of the gems and other stuff are metric perfect sizes.
I'll have to go into the shop and compare the two, as you said, Loring. At least it will probably be able to control the depth better with the drill bits, so maybe a trade off there, because depth is also very important. Thanks to all!

[LCHIEN]

last nite i drilled 1/4 3/8 and 1/2 holes with regular drill bit, forstner and brad point. And then sectioned it on the table saw.

the forstner was pretty much dead flat across the bottom except for the center hole and maybe just a nick at the outer edge.

The brad point was close to but not dead flat - the spurs on the outer edge cut a little deeper and there was a slight rise across the entire bottom towards the center, which if course had the hole in it, too.

post a picture later.

[phi1l]

How much of a flat bottom am I going to get with brad point bits? That's sort of important for what I'm doing, that's why I wanted the forstner bits, but they don't seem to exist.

In that case you might want to consider using a router and a small mortising bit to make bigger holes you can make a template circular template.

[LCHIEN]

the following pictures
each show from L to R Brad point, Forstner, and 118° drill bit

The first picture is 1/2", the next is 3/8" and the last is 1/4"
The fourth picture is the whole thing.
Drill press at 1900 RPM.

you can see the forstner is dead flat except for the center spike, the brad point has a spur on the outside and a slight rise across the bottom.
The brad point were a Delta set I got many years ago, I think it may well depend on the grind, I now realize should have tried different brad point sets, I have at least three.

[Uncle Cracker]

Maybe I'm not picturing this right, but it seems like you're worried about what the bottom of the hole looks like behind the gems you are inserting. Is this right? If so, then they must be clear gems for it to matter, right? So, why don't you insert a piece of cardstock or other such media behind the gem to conceal the slop at the bottom of the hole? This would allow you to control or enhance color, or even to use something reflective (like tinfoil) to reflect the light and create more dazzle. And it would mean you don't have to be so concerned about the appearance of the hole you are boring. Just a thought...

[pecker]

Or maybe just put a drop or 2 of colored epoxy in the hole. It should level out to a flat bottom.

[herb fellows]

Loring, that's pretty much what I concluded also, so I don't think the other sets would show a difference. Thanks for the experiment!
UC, They are mostly dark colored, so the appearance behind doesn't matter. The reflective aspect of tin foil or whatever is something to consider with the more transparent gems though, thanks for that idea.The flatness needed is because the gems, as bought, are dead flat on the back. I was going to use ca glue to hold them in, does that have any 'gap filling' properties?
Or maybe the epoxy idea is good?

I will end up experimenting of course, just wondering if anybody had any thoughts on this. Thanks!

[woodturner]

I was going to use ca glue to hold them in, does that have any 'gap filling' properties?

There is a variety of CA glue that has "gap filling" qualities. It's thicker and sold as gap filling super glue. Woodturning suppliers have it, among others.

Model airplane folks achieve the same result by adding filler, either glass beads or baking soda, to regular CA glue.

[herb fellows]

Baking soda? Really? Whodathunkit?! I have a 10 lb bag sitting in my basement, now I know how to use some of it at least! Thanks for that info!