Forstner Bits

[brucen]

Another dumb question from a noob....

I needed a 35mm forstner bit to drill a blind start hole for my router insert so I bought a 16 pce kit from Carbatec in Sydney (actually I got it via exchange of a returned item). Now the question...

Are forstner bits ONLY for shallow blind holes or can they be used for through holes as well? Just wondering as I don;t have a very good set of twist drills yet....

Cheers
Bruce

[bennylaird]

I have used them for through holes with no problems at all. If your worried you can always clamp some sacrificial backing on anyway.

[brucen]

I have used them for through holes with no problems at all. If your worried you can always clamp some sacrificial backing on anyway.
Cool, thanks Benny. I can see myself using them more often then :)

Cheers
Bruce

[AlexS]

You'll get a much better result if you drill into a sacrificial backing piece - otherwise you can get a bit of splintering, depending on whay wood you're drilling.

There are no dumb questions.

[soundman]

brycen, just a point.
Remember that these bits are not high speed steel and will need sharpening from time to time and may not be real sharp out of the box.
Invest in a small "mill bastard " file and a small triangular file & learn to sharpen them. it isn't hard.
BTW are they true forstners (continuous rim) or are they saw tooth.
cheers

[Pete J]

Just wondering as I don;t have a very good set of twist drills yet....


Brucen

As twist drills aren't specifically designed for timber, maybe it might be worth your while looking at brad point drills, lipped for preference. Very clean cut in timber. Sorry if this is old news to you.

Regards

[brucen]

Thanks Guys

AlexS: thanks for the tip, when through drilling I will definately use a scrap under the work.

Soundman: Thanks for the heads up. I have never used forstner bits before. Now I am a bit worried though about the sharpening bit, never done that before either! They are "real" forstner's, continuous edge. I read that the saw tooth ones were used for end grain drilling and at the moment I can't forsee me doing that in the near future. Then again, I could be wrong.

Pete J: Thanks, I saw these in the Carbatec cattledog and wondered about them. Might make a set the next drilling investment. Oh, an you were telling me something I didn't know, I am shiny new outs-the-box when it comes to semi-serious woodworking (full size stuff!). Been doing engineering type stuff for a while but the woodie bit is brand new.


Cheers
Bruce

[soundman]

Don't sweat the sharpening It isn't hard, except for the small ones they are a fiddle.
Doing the inside rim on the true forstners can bi a bit of a fiddle, but its the cutting edge that need the attention.
Just lay the file flat on the face of the cutting edge & take a few strokes I support mine in a partly open wood vice.

The brad points are a real good thing. The carbide tip ones are a better thing.
cheers

[brucen]

Don't sweat the sharpening It isn't hard, except for the small ones they are a fiddle.
Doing the inside rim on the true forstners can bi a bit of a fiddle, but its the cutting edge that need the attention.
Just lay the file flat on the face of the cutting edge & take a few strokes I support mine in a partly open wood vice.

The brad points are a real good thing. The carbide tip ones are a better thing.
cheers
Thanks soundman

I'll give it a go. I have a set of 6 thru 54mm bits so the little guys should be interesting :)

I have some brad points circled in the Carbatech catalog, they will be my next purchase. They are carbide tipped and have spurs.

Cheers
Bruce

[Iain]

You can also drill a 1/16" pilot hole as a reference point and use the forstner bit half way and then attack from the other side.
There are also spade bits as well as brad points.

[brucen]

You can also drill a 1/16" pilot hole as a reference point and use the forstner bit half way and then attack from the other side.
There are also spade bits as well as brad points.
Good tip Iain, I'll keep that one on record :)

As for the spade bits - yup, I have them circled in the Carbatech catalog too!

Cheers
Bruce