Author Topic: Forstner bits  (Read 1577 times)

Offline Auldfart2010

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Forstner bits
« on: December 19, 2020, 06:55:54 PM »
Hi, total newbie here. I see on youtube that there are turners who use forstner bits for initial hollowing out. I got google fatigue trying to find out if carbide cutters were any good compared to the steel ones for using in the tailstock.
Does anyone have any experience that they can pass on to me?

Offline Twisted Trees

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Re: Forstner bits
« Reply #1 on: December 20, 2020, 01:02:26 AM »
I had a complete new set of forstner bits to 75mm for Xmas last year, the 55mm to 75mm are the carbide toothed ones, and they are a pain! the tooth cuts a grove deeper than the hole gets cut, when turning a box and using a forstner to speed it up I curve out the bottom and often recut the sides to hide the fact I cheated but that groove is hard to get out cleanly.

Another unrelated tip for using Forstner bits is if you have 2 the same size, and you want to make square bottom holes (e.g. 50mm for tealight holders) grind the point off of one of them, start your hole with the standard pointed one, once you have a shoulder to support the bit swap it out to the ground one and you will have a nice flat base without the point mark to clean out.
TT, AKA Pete, but that name is taken :-)

Offline Paul Hannaby

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Re: Forstner bits
« Reply #2 on: December 20, 2020, 01:55:25 AM »
I would just use a twist drill for starting hollowing because they are generally longer, are less hassle to use and are invariably HSS so they drill lots of holes in wood before they need sharpening. If you shop around there are some reasonably priced ones.

Offline Bill21

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Re: Forstner bits
« Reply #3 on: December 20, 2020, 11:18:35 AM »
You can use a Forster bit to produce a finished hole apart from a little sanding and tidying up the end. If it’s just to start a hole though I wouldn’t bother, as said a twist drill is quicker. I have reduced shank Blacksmiths drills up to about 30mm, they aren’t expensive.






Offline Wood spinner

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Re: Forstner bits
« Reply #4 on: December 20, 2020, 01:19:06 PM »
Do you intens drilling end grain or side grane ?

One uses a forstner the other a sawtooth cutter

Offline Auldfart2010

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Re: Forstner bits
« Reply #5 on: December 20, 2020, 01:53:32 PM »
Do you intens drilling end grain or side grane ?

One uses a forstner the other a sawtooth cutter

Both really. Would a sawtooth do both at a push?

Offline Auldfart2010

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Re: Forstner bits
« Reply #6 on: December 20, 2020, 01:55:04 PM »
I had a complete new set of forstner bits to 75mm for Xmas last year, the 55mm to 75mm are the carbide toothed ones, and they are a pain! the tooth cuts a grove deeper than the hole gets cut, when turning a box and using a forstner to speed it up I curve out the bottom and often recut the sides to hide the fact I cheated but that groove is hard to get out cleanly.

Another unrelated tip for using Forstner bits is if you have 2 the same size, and you want to make square bottom holes (e.g. 50mm for tealight holders) grind the point off of one of them, start your hole with the standard pointed one, once you have a shoulder to support the bit swap it out to the ground one and you will have a nice flat base without the point mark to clean out.

I will avoid the carbide ones then, thanks for the square bottom tip.

Offline Wood spinner

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Re: Forstner bits
« Reply #7 on: December 21, 2020, 07:17:07 AM »
Do you intens drilling end grain or side grane ?

One uses a forstner the other a sawtooth cutter

Both really. Would a sawtooth do both at a push?

Only if burt and smoking wood is OK , Bit like chainsaw chains , bandsaw blades ,hand saws Etc

They all come in ripping and crosscut 

Offline Alan Rowe

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Re: Forstner bits
« Reply #8 on: December 24, 2020, 09:58:45 AM »
Which one is used for which orientation please?

Offline Wood spinner

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Re: Forstner bits
« Reply #9 on: December 24, 2020, 11:30:02 AM »