Brad point bits. What are the advantages? Especially for dowels?

[Packard]

Also note that a “spur bit” isn’t exactly the same as a brad point drill.
The spur bit center point is more robust (more like the bullet point) and is less susceptible to following misleading end grain.

But the image looks like a brad point bit.

 

[Packard]

I just got an email notification that the Montana bits arrived.  When I get home, I will try them and respond here.

 

[Crazyraceguy]

Also note that a “spur bit” isn’t exactly the same as a brad point drill.
The spur bit center point is more robust (more like the bullet point) and is less susceptible to following misleading end grain.

But the image looks like a brad point bit.

It does. It may be a very slight thing and maybe even very by brands, but my Fisch Brad points are a little more exaggerated at the cutting edges.

Like spade (paddle) bits. Some are just flat, other that the spear point, others have little points at the edges. Some even go so far as to have an under-cut, to give a positive cutting rake. Irwin?

 

[Michael Kellough]

Maybe Garrett Wade (or the jig manufacturer) meant brad point but wasn’t sure anyone would know what they meant?

Whether you call them by different names or not there are different types of brad point drills.

A description of the different types and uses of brad point drill bits.

 

[Packard]

The Montana bits arrived.

Initial observations:

1.  These bits are shorter than my other bits.  About 1/2” shorter across the board.  All are long enough to use with the jig.
2.  Sizes 1/8” to 1/2”
3.  Blister pack; no case.
4.  The 1/8” size has a round shank.
5.  All the other sizes have three flats milled in the shank, a useful feature.
6.  Laser marking is small, faint, and difficult to read.

I tried these in pine and none were warped.  All spun true.
Freehand all had ragged lead in, but in the jig all cut cleanly and fast.  These bits are sharp.

I did not test the 1/8” in any jig.  Freehand, the start was ragged too.

I have no idea why I could not get clean holes freehand. I did not try these in the drill press, but I assume those will be clean too.

I  think these will serve me well. If you are considering these, note the short length, and lack of any holding case.

Of course the DeWalt bits are similarly packaged with no case, but I think they are longer.

These will work for me.  I am not going to return these.

 

[Mini Me]

At least Forstner bits provide a means to extract the chips from the hole. Hole saws are generally terrible at that. The older "Professional" line of Craftsman hole saws has 2 very large gaps in the teeth, which help some, but not nearly as good as Forstner bits. I think those openings were really there to help with plug removal, but accidental benefits are still nice.

Most everyone I see runs them both way too fast, which overheats them.

[member=44099]Cheese[/member] I'm certainly not going to pick at you over it, if it works for you, so be it. The job looks great.

Try drilling two holes as I mentioned in another post, it really does work

 

[Cheese]

Try drilling two holes as I mentioned in another post, it really does work

Ya thanks for that...I will try it the next time I "hole saw". Cedar seems to really be an issue because the chips are so soft and they completely pack into the gullets of the hole saw leaving it "toothless".

 

[Packard]

I’ve used the relief hole technique.

I start the hole saw just deep enough to reveal the outline.  I drill one 3/8” hole that just intersects the interior of the hole.

Why drill 2 holes?  One hole seemed to work.

The other problem with hole saws is that it is sometimes difficult to remove the trapped disc in the saw.  Some have an access hole to drive it out, but most have slots on the sides to lever it out.  It’s easier in the drill press where you don’t have to use the pilot hole.

 

[ChuckM]

Yes, one hole is enough. I know some prefer two holes so they can use a pair of long nose pilers to pull the stuck disc.

 

[Crazyraceguy]

I’ve used the relief hole technique.

I start the hole saw just deep enough to reveal the outline.  I drill one 3/8” hole that just intersects the interior of the hole.

Why drill 2 holes?  One hole seemed to work.

The other problem with hole saws is that it is sometimes difficult to remove the trapped disc in the saw.  Some have an access hole to drive it out, but most have slots on the sides to lever it out.  It’s easier in the drill press where you don’t have to use the pilot hole.

The ideal method, in a hand-held situation, is to drill about 75% of the way through from one side. Then come in from the other side, this will make the plug break off in the middle. Two things happen here, the plug is mostly sticking out of the saw, making it easy to remove. The other thing is reducing the chance of tear-out on the back side.

 

[Cheese]

The ideal method, in a hand-held situation, is to drill about 75% of the way through from one side. Then come in from the other side, this will make the plug break off in the middle. Two things happen here, the plug is mostly sticking out of the saw, making it easy to remove. The other thing is reducing the chance of tear-out on the back side.

I've used that method a lot for cedar, the only issue is that there's always a slight difference in alignment with the two holes. I think that in soft cedar the pilot drill is the guide for just a short depth, after that the hole saw takes over and becomes the actual guide and it forces the pilot hole out-of-round. Flip the board, complete the cut and the two holes will not be co-planer. I assume there is less of an issue when using maple, oak, walnut et al.

 

[Packard]

When I need really clean holes from a hole saw, I back the hole up with a piece of scrap wood.  There is usually no tear out when I do this.

It works very similarly to backing up rails when cutting the ends with a coping sled. 

I too find that drilling from behind ends up leaving a “shelf” where the registration is not perfect. 

When I build a pour over coffee stand a while back, I arranged for that seam to be near the one edge I was planning on doing a roundover with my router.  The router cut hid the lack of registration.

But in the end, if you want a really clean cut, then the backer board is the way to go.  Just keep some scrap lumber in the house for this.  Even 1/4” thick ply will work for this application (though I usually like 3/4”, so I can drill over my work bench and not penetrate the bench.)

 

[Crazyraceguy]

If I needed a hole that had to be that nice, like it would be open and visible, I wouldn't do it with a hole saw in the first place. Forstner bit or template and router, depending on size

 

[Packard]

If I needed a hole that had to be that nice, like it would be open and visible, I wouldn't do it with a hole saw in the first place. Forstner bit or template and router, depending on size

Typically the hole is covered by the “rose” of the lockset, and typically the rose is about 1/2” larger than the hole.  That is why a ragged hole is not usually an issue.

How was that hole drilled in 1953 when my house was built?  Did they make auger bits over 2” to be used with a manually operated brace?

 

[luvmytoolz]

You can still buy adjustable auger bits that are surprisingly easy to use with a brace.

 

[Cheese]

I've been replacing my Colt Twin-Land brad point bits with some made by Fuller in Rhode Island. Here's how each Fuller drill bit arrived, individually packaged in a heavy duty envelope with the brad point completely coated with dip seal.  [cool]

[attachimg=1]

[attachimg=2]

[attachimg=3]

Here's an interesting comparison in the brad point geometries between the Fuller on the left and the Twin-Land on the right. 

Also, those dual lands do provide additional guidance when drilling free hand but they also produce a lot more heat which tends to burn the holes and blue the drill bits.

[attachimg=4]

 

[Packard]

Interesting.  I will check the geometry of my bits when I get home.

 

[BarneyD]

+1 on the Fullers. A few years ago I bought a 14 pc. set in an index (perhaps from McFeely's, don't remember). They are a bit pricey, but the quality is excellent. Best brad points I've ever used.

 

[Packard]

I don’t know why it is viewing so large.  These are th 3/8” and 1/2” Montana bits. The grind looks different than the Fuller bits.

It appears that they added a black oxide + oil finish after sharpening.  Blister pack is as effective as the dip in preventing damage to the tips.

Black oxide adds no corrosion protection, but the oil does.  They claim that the oil adds 100 hours or more to the salt spray rating, but that is only when the parts are dripping in oil.  These are just oily enough to get my hands dirty and would likely get a salt spray rating of less than 5 hour.  In other words, just enough corrosion protection to make the trip from Montana to New York.

 

[Cheese]

Interesting.  I will check the geometry of my bits when I get home.

I noticed this last night when I was putting things away. These are all 5 mm brad point drill bits. Notice the differences in point geometries and the rates of twist, starting on the left.

1. Made in Germany, 1 rotation per 34 mm
2. Made in USA, 1 rotation per 18 mm
3. Colt Germany, 1 rotation per 28 mm
4. Fuller USA, 1 rotation per 29 mm

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