Can anyone recommend a fine grade hole saw?

[bing!]

I had a Craftsman hole saw that I use for making holes on my kayak. I started making a fishing rod rack today and used what I already had. The saw rips up the wood when it exits. This is despite having 3/4 plywood backing the workpiece. I was using a drill press on the lowest speed setting, thinking this will prevent wood burning. How can I make a furniture grade hole? Finer saw? More speed?

Thanks in advance!

/bing

[charliex]

I drill most of the way through on the face side, then flip the work and finish from the other side, thus preventing blow out. This also makes removal of the plug easier because it's not buried in the saw. Another thing that helps when using a hole saw is to just lightly start the hole, then just inside the rim of the hole drill a hole. This gives the sawdust a place to go reducing friction and burning.

Chas

[LCHIEN]

I drill most of the way through on the face side, then flip the work and finish from the other side, thus preventing blow out. This also makes removal of the plug easier because it's not buried in the saw. Another thing that helps when using a hole saw is to just lightly start the hole, then just inside the rim of the hole drill a hole. This gives the sawdust a place to go reducing friction and burning.

Chas

that's both good advise from Charlie. Since the pilot bit makes a through hole first, its easy to use that pilot hole (or drill one separately) as a guide and you can drill perfectly matched holes from each side with no blowout and saving the plug digging PITA.

When using hole saws i really find the second tip given, to drill a relief hole (say 1/2" to 1" dia) intersecting the hole saw kerf, is great. this lets the cuttings exit the hole and not fill the teeth and burn! the relief hole can be either on the inside or outside depending on whether the hole has to be good or the disc has to be good.

[phi1l]

From what I have seen, fine grade hole saw is an oxymoron.

[cabinetman]

I drill most of the way through on the face side, then flip the work and finish from the other side, thus preventing blow out. This also makes removal of the plug easier because it's not buried in the saw. Another thing that helps when using a hole saw is to just lightly start the hole, then just inside the rim of the hole drill a hole. This gives the sawdust a place to go reducing friction and burning.

Chas

Good advice that can also apply to holes not done on a DP, like handle and lock sets for passage doors.
.

[LCHIEN]

Actually Phi1l is right, you really want a forstner bit if you want nice clean holes. But you still need to be careful about blowing out the backside.

[cabinetman]

Actually Phi1l is right, you really want a forstner bit if you want nice clean holes. But you still need to be careful about blowing out the backside.

For through holes, a hole cutter would be easier as it doesn't have to plow out all that wood. Another thing is many forstners have short pilot bits which won't poke through the other side until it's almost all the way through.
.

[LCHIEN]

Large diameter holes 201 : Hole saw vs. Forstner

the way I see it is that the Forstner will cut a much smoother edged hole - the forstner has rim cutters which will cut a more defined, smoother wall than the hole saw which usually has set teeth and cut a more ragged side hole.

The hole saw has a real drill bit which can usually be set to the depth you want so it can cut a perfect pilot hole all the way thru and its easy to re-enter perfectly centered from the back.
The Forstner has a tiny pilot point which is only about 1/16th to 1/8th inch deeper than the bottom cut. If you want to enter the other side then you must watch very carefully until the point just exits the back, then flip it over and re-enter the pilot point from the back, which I have done many times to get a perfectly clean bottom.

The other point C'man makes is that the Forstner removes all wood whereas the hole saw just cuts the rim and leaves a disk. This goes either way, if you need to make disks then use the hole saw. if you need a cleaner hole wall the use the forstner.


The forstner clearing out all the wood makes a better cut because the cuttings are all ejected. The hole saw really has no exit for the cutting except to lift the saw periodically and clear the hole. Excessive drilling and not enough clearing causes the wood cuttings to be trapped in the slot, and jammed into the teeth so that the saw is riding on the wood cuttings rather than the teeth and justs heats up and burns rather than cutting.
So you need to use the trick mentioned earlier in the thread to clear the slot, or keep raising and trying to clean the teeth to cut w/o burning. I find a forstner for all the wood removal is still maybe faster than hole saws since you don't have to keep clearing the teeth and the slot kerf and the hole is so much nicer and very accurate in diameter.

For the OPs purpose of cutting a fishing rod holder its a tossup as to which is better. If he intends on lining the holes with felt then the hole saw will be adequate. If the holes are to stand alone and be visible then I would use the Forstner. When I made fishing rod holders (only three examples remain the other two having been blown out to sea in Hurricane Ike) I used forstner bits. If the OP wants a finer cutting bit, I assume its for better looking holes, then I recommend the Forstner. - hole saws are mostly for carpentry, forstners are more for woodworking.

this is in rough-cut cedar, not hardwood so the holes a bit rough anyway.


http://www.bt3central.com/showthread...shing+rod+rack

[LarryG]

How can I make a furniture grade hole?

Loring is correct. For the furniture grade hole the OP wants, a Forstner bit is the ticket.

BTW, Loring ... don't you have a BIG picture that you could show us?

[cgallery]

I have some carbide tipped hole saws in a few sizes, that I used when I was building more loudspeaker enclosures.

They do a remarkable job of cutting clean holes.

Though, I still cut from both sides of the board to completely eliminate the risk of blowing the hole out.

[headhunter636]

But you still need to be careful about blowing out the backside.

This has always been a matter of great concern for me, always be careful not to blow out the backside.

(insert sorry attempt at humor here) In my defense, it is rather early.

Dave

[August86]

Backer board

If you're not going to drill from both sides, then use a backer board. clamp everything together to reduce tearout as much as possible. This is for any drill bit including Forstners.

For boats you may hare to shape a piece of scrap to fit tightly.

[cgallery]

This has always been a matter of great concern for me, always be careful not to blow out the backside.

(insert sorry attempt at humor here) In my defense, it is rather early.

Dave

[Chuckling]

You're doing just fine.

[bing!]

Great stuff. Thanks for all your replies! /bing

[crokett]

Woodcraft has a set of carbide-tipped hole saws. They are expensive though. I do what has been recommended and I flip the piece over.