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By worn thumbs
#1322400
Some sound advice already given and I would add one further recommendation;if you see an Irwin expanding bit with both [i][/i] adjusting wings present do not let it escape. Infinite adjustability from 7/8 inch to 3 inch so you can even produce metric holes with it.

As you might be aware if you ever work on older stuff, screws can get very attached to their surroundings and a brace with a screwdriver bit allows you to lean on the screw head while applying a lot of torque.
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By Sheffield Tony
#1322402
To add to Cheshirechappies list of bits and their uses:

Gedge bits for some reason work better for end-grain boring that the rest.
Spoon bits make it possible - with practice - to bore a bole that is slightly wider at the bottom than the top. Potential fun combination with fox wedging.
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By ED65
#1322440
Andy P Devon wrote:...drilling the odd pilot holes (although I try not to use screws)...

Cheshirechappie mentions which bits would be most suitable for this but something nobody has touched on is a brace isn't the right drill type for day-to-day pilot holes. Maybe if you're piloting for a coach screw or something of that sort of size but for screws in the normal range a hand drill (eggbeater) is the better choice, assuming you're not using a power drill.

If you have a grinder and you want to use twist bits it might be worth converting a small set of them for wood only. The standard grind angles on twist bits are intended for metal and while they will certainly drill wood they can work better if adapted specially, and you only need to do a handful of sizes for pilot and clearance holes.
By xy mosian
#1322673
ED65 wrote:If you have a grinder and you want to use twist bits it might be worth converting a small set of them for wood only. The standard grind angles on twist bits are intended for metal and while they will certainly drill wood they can work better if adapted specially, and you only need to do a handful of sizes for pilot and clearance holes.


Hi ED65, from long memory I believe the point angle of 'standard' twist drills is 118 degrees. What is the best angle for wood?
Thanks in advance, xy
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By ED65
#1323120
xy mosian wrote:Hi ED65, from long memory I believe the point angle of 'standard' twist drills is 118 degrees. What is the best angle for wood?

Something lower than this, i.e. a steeper bevel. The precise angle can't be that important given a 118° included angle works all right and I've seen recommendations for 60°, 75° and 90° for wood in various places. The main thing seems to be for the bit to have a more pronounced point.

Image
For anyone who wants to give this a try on a spare bit or two, there are numerous good guides to grinding bits on YouTube. The one that unlocked it for me was this one: https://www.youtube.com/watch?v=-wXBbbDVksk from That Lazy Machinist. Fair warning, the audio isn't the best on this because it was recorded in a large echoey machine shop, but it breaks the freehand method down into the simplest, easily remembered and repeated steps.
By xy mosian
#1323201
ED65 wrote:
xy mosian wrote:Hi ED65, from long memory I believe the point angle of 'standard' twist drills is 118 degrees. What is the best angle for wood?

Something lower than this, i.e. a steeper bevel. The precise angle can't be that important given a 118° included angle works all right and I've seen recommendations for 60°, 75° and 90° for wood in various places. The main thing seems to be for the bit to have a more pronounced point.

For anyone who wants to give this a try on a spare bit or two, there are numerous good guides to grinding bits on YouTube. The one that unlocked it for me was this one: https://www.youtube.com/watch?v=-wXBbbDVksk from That Lazy Machinist. Fair warning, the audio isn't the best on this because it was recorded in a large echoey machine shop, but it breaks the freehand method down into the simplest, easily remembered and repeated steps.

Thanks for that Ed, strangely that is the exact image I found last evening. The different point angle, for wood, is mentioned now and again, but I admit this is the first time I have sought to find the answer. I must grind some drills when the workshop/garage warms up.
Luckily I am old enough to have been taught the joys of regrinding drills at school. These days anything below about 4, or 5, mm can be a bit hit and miss but I'll give it a shot. I don't recall seeing any sets 'For wood' for sale, perhaps someone is missing a trick.
Thanks again, xy