Settle a dispute for me - countersinking technique

[Noah]

On another forum, a member has stated:

"Actually no, a Forstner bit cuts a sharp edged hole due to the nature of the cutting surface. The bit you have shown (countersink bit and matching plug cutter) is merely to drill a pilot hole and set a counter sink for a screw. It should be used AFTER you have used the Forstner bit to make the bore hole for the plug."

Am I crazy thinking that you generally just use a countersink and then set a bung - not pre-drill with a forstner bit then countersink, then bung. I would think you would screw up the hole 50% of the time with the other method.

Set me straight, I'm ready to learn if I need to.

[Todd D]

I use the counter sink bit drill the pilot hole and make the hole for the bung. Occassionally I use a forstner bit to clean the hole up if it looks a bit ragged so the bung will fit more easily. I have never started the hole with a forsner bit.

[StevenBauer]

The whole purpose of the countersink bit is that it bores for the bung while drilling the pilot hole. That poster sounds confused.


Steven

[kc8pql]

The whole purpose of the countersink bit is that it bores for the bung while drilling the pilot hole. That poster sounds confused.
Steven
agreed

[Duncan Gibbs]

The whole purpose of the countersink bit is that it bores for the bung while drilling the pilot hole. That poster sounds confused.

Or a fussy perfectionist with no time contraints.

[Paul Girouard]

Almost for sure that posters is not making a living out of working wood.

If he is he's one of those few fussy / read expensive, WWers.

What say ye Lefty;)

[Paul Girouard]

Great minds think alike eh Dunc:D

[Eric Hvalsoe]

The statement in question is quite confusing. I think the fella is a little confused, maybe the nomenclature is getting mashed up. People often use tapered bit/countersink (ie Fuller brand).
combinations. However the tapered bit does not always give the necessary bore - say running bronze through something really tough. So I might drill through again with a straight bit, after the combo bit, to get just the clearance I need. Or I might 'clearhole' the piece I am fastening so It does not split. I dunno what the guy was talking about. Might use a forstner bit for counterboring a bolt head, although that is more easily done with a Fuller counterbore slipped onto a straight bit. There are also stepped pilot/countersink combinations.

[goodbasil]

Your right Noah, they are wrong. If they have anymore doubts, send them here.

[peter radclyffe]

the centre of a flat bit, or spade bit extends for a reason, to start a hole on an angle, i.e. drilling a curved bow plank, you cant do this with a forstner, a forstner is used in particular when you need a plug in fine joinery

[RodB]

I recently bought a really nice Fuller kit with 5 tapered bits and countersinks... each size as one tool, along with a plug cutter and dept stops...
http://www.amazon.com/quick-change-countersink-counterbore-predrill/dp/B001AQ0ZXU/ref=pd_cp_hi_1

Its really nice to be able to countersink the screw and drill the hole for the plug all in one step. I've been wanting this kit for a while...

RodB

[boattruck]

Noah, Back in the day, before the availability of the nice sharp Fuller type taper bits and counter sinks, a fellow would counter sink with a forstner type, drill for the shank size, then drill for the root screw size, we also had to walk uphill six miles to school in freezing sleet...I am glad to do it all in one step if I can, although the counter sinks can get pretty dull pretty quickly and sometimes it actually saves pushing your guts out to use a separate forstner type for the countersink...Do what works for you, let the chorus sing whatever they want, Cheers, BT

[Gezzunder]

What the fellow meant was correct if you are going to place a plug over a screw head. Forstener bit does the recess for the plug, then drill/countersink for the screw. Plug is placed after screw is driven.

If you drill the screw hole first, it's almost impossible to cut the pocket using a forstner bit as it will try to wander all over the place.

Where he confused everyone is using the term 'bung' instead of 'plug'

[Duncan Gibbs]

This guy's saying cut the hole with the forstner bit as it will give a clean cut, then use a countersink to set the screw head flush into the hole, then use the plug/bung cutter to make said plug/bung (you say tomaytoe, I say tomartoe ;)) and set said plug/bung with favourite adhesive... Shellac if you REALLY want to be trad' about it.

Most lazy bastards (take a pinch of salt here people) will just use a countersink to cut the hole AND set the screw head flush in one hit. Like I said, the guy is just a fussy perfectionist: Nuttin' wrong wit dat!!

[outofthenorm]

I recently bought a really nice Fuller kit with 5 tapered bits and countersinks... each size as one tool, along with a plug cutter and dept stops...
http://www.amazon.com/quick-change-countersink-counterbore-predrill/dp/B001AQ0ZXU/ref=pd_cp_hi_1

Its really nice to be able to countersink the screw and drill the hole for the plug all in one step. I've been wanting this kit for a while...

RodB

I bought that set from Lee Valley 20-something years ago. Expensive, but worth every penny. I've used them thousands of times - literally - and always been happy with the result. With a little care, bungs can be almost invisible.

The bung cutters in that set make tapered bungs that fit perfectly almost every time. You have to sharpen all the cutters now and again, but that's pretty easy.

As Eric said above, the tapered drill bits are not always right, especially for harder woods, but that's easy to deal with as well.

- Norm

[David G]

This guy's saying cut the hole with the forstner bit as it will give a clean cut, then use a countersink to set the screw head flush into the hole, then use the plug/bung cutter to make said plug/bung (you say tomaytoe, I say tomartoe ;)) and set said plug/bung with favourite adhesive... Shellac if you REALLY want to be trad' about it.

Most lazy bastards (take a pinch of salt here people) will just use a countersink to cut the hole AND set the screw head flush in one hit. Like I said, the guy is just a fussy perfectionist: Nuttin' wrong wit dat!!

Agreed. I think it's important to make the distinction between countersinking and counterboring. Countersinking is for drilling a shallow, conical depression that will allow the head of a flathead screw to lie flush (us just under flush) with the surface. Counterboring is for drilling a deeper, cylindrical hole - either to get the screw head completely out of the way, or to allow the use of shorter screws than would otherwise be necessary, or to make room for the later insertion of a bung.

A true countersink bit cuts only the cone. No pilot hole. No shaft clearance hole. A Fuller brand combination bit has a tapered drill bit to make a pilot hole, and it has a countersink attached further up the shank, and adjustable, so that the depth of the pilot hole can be varied. A forstner bit will cut only the (very clean and accurate) counterbore. No pilot hole. But it will leave a slight centered depression at the bottom of the hole where you can start your pilot bit, or shaft clearance bit. Same with a spade bit. Spade bits, however, tend to cut a ragged hole, and need to be kept very sharp to hope to avoid such bad behavior.

It's also true that the Fuller bits can frequently be used to cut pilot, countersink, AND counterbore. This is particularly true for softer species, and thinner planking. For a larger boat, with thicker planking, of a denser species... you might begin to think about counterboring first.

So... Noah. The answer to your question - as is often this case - is... It Depends. As always, there are lots of ways to skin the cat. Your debating partner is technically correct. If the topic was fine furniture, then he was more correct than not. If the topic was planking a small boat, then you were probably more correct than not.

In general, people who argue that there is one "correct" way to accomplish some woodworking task alternately amuse or irritate me. In my experience, the best way to tackle a task has to factor in such things as: skill level; tools available; working conditions; schedule; money; fatigue level; etc. The more experience you have, the better you'll be able to judge which approach makes sense for your particular circumstances.

[Jay Greer]

This actually reminds me of an argument I once overheard between two sailing friends who were going to bring some Mexican take out food to the boat we were crewing on. The argument was that of the difference between Mexican food and Mexican Foods being posted on the sign out side of the resaurant. One contendend that if the sign said Mexican Food then they, technically, were offering one food or one item. The other insisted that in order to offer more than one food, the sign should read "Mexican Foods". My comment was, who cares?

I always use Fuller Counter Bores for standard size plugs. If the hole needs enlarging, beyond the standard sizes of Fuller counter bores, I may use a Forstner Bit in a wooden quide plate and custom turn the odd sized plug on my metal lathe. Even so, the conical portion of the hole, for a flat head screw, must be cut with either a counter sink or a counter bore. The counter bore is better as the taper drill will pilot the cutter on center. Futzing with a Forstner cutter is a waste of time, except for a special need.
Jay

[Ian McColgin]

I either don't understand or disagree with some of the implied order. If I'm to counterbore for a bung and for whatever reason the tapered one-step is either not available or not suitable - perhaps I'm setting a bolt - I drill the counterbore first with usually my hand auger but sometimes with a fostner or other quality brad point bit. This gives a fine starter hole for whatever size hole I need for the fastening, so much easier to center than to get the conterbore centered over the pilot hole.

G'luck

[pcford]

I guess I am don't understand. Forstners are usually used in a drill press. However, a quick Google shows several bit types all being called Forstners. For example a spur bit was called a Forstner. I have never seen a Forstner (of any type) used in creating a countersunk screw hole.

Fuller makes countersinks and counterbores. Counterbores have a flat bottom...

[Jay Greer]

I guess I am don't understand. Forstners are usually used in a drill press. However, a quick Google shows several bit types all being called Forstners. I have never seen a Forstner (of any type) used in creating a countersunk screw hole.

Fuller makes countersinks and counterbores. Counterbores have a flat bottom...
A power Forstner bit can be used for cutting a clean hole if it is guided by a pre-bored guide plate made of ply-wood. The quide is centered over the hole to be cut and held down by either lead blocks or fine brads.
Jay

[RodB]

I bought that set from Lee Valley 20-something years ago. Expensive, but worth every penny. I've used them thousands of times - literally - and always been happy with the result. With a little care, bungs can be almost invisible.

The bung cutters in that set make tapered bungs that fit perfectly almost every time. You have to sharpen all the cutters now and again, but that's pretty easy.

As Eric said above, the tapered drill bits are not always right, especially for harder woods, but that's easy to deal with as well.

- Norm

Great... I was at Woodcraft and the salesman noticed I was interested in that set... he handed me a 15% off card... so I bought it... Glad to hear this is a good investment... I plan to use it a long time.

RodB

[Bill Perkins]

Norm ;I've got the same set . How do you sharpen yours ?

[Mrleft8]

Almost for sure that posters is not making a living out of working wood.

If he is he's one of those few fussy / read expensive, WWers.

What say ye Lefty;) Sounds like someone gave someone else some bad advice at some point.


Norm ;I've got the same set . How do you sharpen yours ? Send 'em back to Fuller.

[Jay Greer]

Fuller bits can be hand honed on a diamond plate or water stone. Some of mine are forty years old and still cutting clean.
Jay

[Wooden Boat Fittings]

Where he confused everyone is using the term 'bung' instead of 'plug'

Except that what we call 'plugs' the Yanks call 'bungs.' :)

Personally, I don't even know what a "Forstner bit" is. But any of our fittings that are big enough to warrant the bolt-heads being plugged after fastening, are first drilled for the plug using a spade bit, then for the bolt using pilot and clearance bits centred in the indentation left by the spade bit.

And of course if they're to be screwed into place rather than bolted, then a countersink is used after the clearance hole has been drilled, at the bottom of the counterbore produced by the spade bit.

Mike

[Eric Hvalsoe]

Perhaps the words countersink and counterbore are blurring together. I refer to the fuller tapered bit/countersink combination. Whether I set the screw flush, or deep for a plug or bung or whatever you want to call it, it is still a countersink bit, with a beveled shoulder, for screws. To me a 'counterbore' has a flat shoulder - for a bolt - the Fuller counterbores, or a forstner bit (very little pilot point), or a spade bit for that matter.

[peter radclyffe]

http://www.woodenboat.com/forum/images/buttons/reply.gif (http://www.woodenboat.com/forum/newreply.php?do=newreply&noquote=1&p=2308875)

[David G]

Perhaps the words countersink and counterbore are blurring together. I refer to the fuller tapered bit/countersink combination. Whether I set the screw flush, or deep for a plug or bung or whatever you want to call it, it is still a countersink bit, with a beveled shoulder, for screws. To me a 'counterbore' has a flat shoulder - for a bolt - the Fuller counterbores, or a forstner bit (very little pilot point), or a spade bit for that matter.

Eric - agreed. See my post #16