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Brad point bits with accurate tip

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I have several sets of Brad Point bits, some expensive, some mid range. But a problem I find with a lot of them is that the tip is not always very central or runs true. I can put the bit in the drill press or on the lathe, and the whole thing runs true except for the point on the end. Which is very frustrating when you have marked a point with an awl for the bit to follow (when working on the lathe, I'll use the skew chisel to mark the center for the bit to follow). Most of my sets have a ground point, like in the picture below. I suspect this process isn't very accurate? is there a more accurate type? not really looking for a whole set, just want a few that I can use for very accurate work on the lathe (or at least more accurate than I am getting).



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Ollie78

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I suspect this is going to be a bit price related unfortunately. I bet the Fisch ones or the Famag have much better precision.

I noticed the same thing last week when using a 13mm brad point in my pillar drill when the point touched it tried to wobble but as soon as spurs hit it was a nice and straight cut. I really hadn`t noticed the tips being off when using them in my battery drill, maybe because it spins faster.
Mine are not cheap and nasty but not expensive either. I was thinking of trying some better ones.

I am quite tempted by these Star-M Japanese 601 Precision Drill Bit Set of 10
They do singles as well.

Ollie
 

Alpha-Dave

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For all my lathe-drilling, I just use ‘standard’ HSS drill bits or Forstner bits, although that is probably because the holes I am making are usually going up to a bigger size than my lip&spur set goes to or are in materials that would not suit lip&spur such as acrylic pen blanks or wood with epoxy resin.
 

chaoticbob

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I have Fisch Set which seems OK to me - no worrying wobble of the points. I don't know how £18.58 for a set of eight sits in the scale of things though - seems good value it to me as the bits cut beautifully.

I suspect that if you need real accuracy (but we don't know what accurate means in this context - better than 0.1mm?) a brad point bit mightn't be the tool of choice. You need to start the hole with a short, rigid drill such as a centre drill as Phil suggested, or a spotting drill .
I should say that I'm new to woodturning and speaking from the perspective of a metal worker, but the general principles are the same I guess.

Bob.
 

hodsdonr

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You need to mike your bits and discard those that are off centre. The distance from tip to spur needs to be identical for each side . any difference here means there was a grinding error in manufacture. I have had cheap drills perfectly centered and expensive ones off centre. Now I drill my pen blanks on the lathe with a good quality machinists drill bit and make certain that the end of the blank is perpendicular to the bit. If that is of then the flutes will hit that side first and deflect the drill bit .
 

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