How to grind brad point bits by hand

**elanjacobs** · 21st November 2019, 07:51 PM

This topic comes up with some regularity, so I've finally gotten around to doing a proper instructional thread. I've tried to get as many photo angles as I can.

Basically, the trick is to let the grinder do all the work for you.

Step 1 is to hunt down a narrow wheel; this seems like the kind of thing that shouldn't be a problem, but we had a hell of a time finding 6" dia x 1/4" wide white AlOx wheels. The narrow wheel isn't essential, but it makes dressing the wheel easier and the majority of bits won't need more width so it seems a waste to use a wider one (and you can always just move wider bits across the face of a narrow wheel anyway).

The wheel is dressed to match the shape of the bit; I've never measured the angle, but it looks about 10 degrees. It's quite worn in the first pic so the corner has rounded off, but for small bits you'll need to keep the corner quite sharp.

IMAG3581.jpg IMAG1487[1].jpg

The tool rest is set to create the back clearance; again, never measured it but it's about 15 degrees. This angle can affect how aggressively the bit cuts, so if your bits self-feed try a flatter angle.

IMAG3582.jpg

Hold the bit on the tool rest so that the spur being ground is slightly higher than, or level with, the other spur and feed the bit into the wheel. When grinding a new twist drill, make sure to leave a thick centre point; it's very easy to get carried away and not have enough material left in the centre, so once you've got the shape roughed out, come back and thin the point down. Creating a centre point that is truly "on centre" is probably the hardest part and does require several trips back and forth to the drill to check how it's running and which side needs to be thinned down, but, if you're careful not to touch the point when touching-up the edge, it rarely has to be corrected.

IMAG3587.jpg IMAG3585.jpg IMAG3586.jpg

You may be left with a thin bit of steel at the back that is not ground away. To remove it, rotate the bit clockwise and reapply it to the wheel, being careful not to catch the other spur on the side of the wheel. You may also need to hold the bit at a slightly higher angle so only the back of the bit is being ground. Forgot to get pics of this bit (sorry), but you'll figure it out

Finally, admire your new HSS brad point drill bit that didn't cost $30+

IMAG3583.jpg IMAG3584.jpg

**auscab** · 21st November 2019, 09:55 PM

Nice demo Elan .

I went searching for thin grinding wheels years ago and have used these guys ever since . I got some red coloured saw sharpening thin wheels for grinding shaper blades . About 4mm x 150 I think . They sell all sorts of stuff though .

http://www.workmate.com.au/

The other thing I do is bolt a used worn down 9" angle grinder cutting disc blade into the bench grinder . I rounded that and have been doing small things on it like drill bits sometimes . I try and do some of the drill bits with a center point as well as the side spurs to slice the grain . Sort of works out sometimes .

The best thing Ive discovered is the its a perfect fit for re sharpening my 3/8 bandsaw blades . Its a bit of a long job grinding! I spent a good 20 years buying 3/8 blades for the workshop and I never sent them off to be sharpened . I'd just hang them on the wall and buy more with the next order of large 1.25" ones . Now I'm in a country workshop and saving a buck any way I can so I'm re sharpening those blades until they break . Don't think its possible Ill go through them all for that saw?

Rob

**China** · 21st November 2019, 11:58 PM

Great tutorial, I was taught how to do this when I was working as wood machinist, many many moons ago, the doweling bit on the machine I was using broke
the foreman just grabbed a standard twist drill and reground it

**Lappa** · 22nd November 2019, 11:48 AM

Nice demo - thanks!

I was also thinking of using an angle grinder off cut wheel - must have a go now it’s been mentioned.

**qwertyu** · 22nd November 2019, 09:58 PM

Thanks for posting this!

Anyone have suggestions on where to buy a 1/4" white wheel? Its not listed on the workmate website

**auscab** · 22nd November 2019, 10:15 PM

Originally Posted by qwertyu

Thanks for posting this!

Anyone have suggestions on where to buy a 1/4" white wheel? Its not listed on the workmate website

Did you see this ? 1.5 to 4mm so not 6.35 or 1/4"

http://www.workmate.com.au/product/s...rinding-wheels

There's white in the pic there but I have Pink . Cuts and shapes HSS spindle moulder tooling no problems , Drills are HSS I think .

Edit . This is a link with the differences between a white and Pink grinding wheel .

The Different Types of Abrasive Grinding Discs | Blog | VJ Tecnhology

**China** · 22nd November 2019, 10:21 PM

You don't need a narrow wheel, just makes it easier can be done on the edge of any width wheel

**qwertyu** · 22nd November 2019, 11:16 PM

Originally Posted by auscab

Did you see this ? 1.5 to 4mm so not 6.35 or 1/4"

http://www.workmate.com.au/product/s...rinding-wheels

There's white in the pic there but I have Pink . Cuts and shapes HSS spindle moulder tooling no problems , Drills are HSS I think .

Edit . This is a link with the differences between a white and Pink grinding wheel .

The Different Types of Abrasive Grinding Discs | Blog | VJ Tecnhology

thanks for that I missed it. It seems like it only comes in packs of 10? Were you able to buy a single wheel?

Originally Posted by China

You don't need a narrow wheel, just makes it easier can be done on the edge of any width wheel

Just seems a bit wasteful to be dressing a larger wheel

**auscab** · 23rd November 2019, 12:20 AM

Originally Posted by qwertyu

thanks for that I missed it. It seems like it only comes in packs of 10? Were you able to buy a single wheel?

No , not one but he didn't make me buy the pack of ten either from memory . It was a while back . I ring Sydney when I want something . I find them great to deal with . You need more than one anyway I reckon, for when you knock one and find out how fragile thin wheels are .
I got an old grinder and built a box around it , fitted a wooden rest on both sides to rest steel on and enclosed the front so I had a much narrowed view to look through. I used safety glasses and look through the narrow part . Just so I don't get a face full if something goes wrong . With two wheels I can have one with a convex radius and the other to a sharp V or what ever I like to shape it to with my diamond dresser.

Thread: How to grind brad point bits by hand

Thread Tools

Search Thread

How to grind brad point bits by hand

Similar Threads

Brad Point Drill Bits - Two Types?

Sharpening Brad Point type Drill bits

Spare Brad-Point Bits for GMC Dowelling Machine?...

Miebach Colt Brad Point Bits

Brad Point Drill Bits.

Posting Permissions