Help cutting 6" hole

["Gary Smith"]

I have the need to cut several 6" holes in sheets of hardwood plywood.
What is the best way of cutting such an hole? Is there a 6" hole saw? The problem I see with a router is mounting a template without damaging the plywood.

[Myk Rian]

I have the need to cut several 6" holes in sheets of hardwood plywood.
What is the best way of cutting such an hole? Is there a 6" hole saw? The problem I see with a router is mounting a template without damaging the plywood.
Use a fly cutter.
http://ep.yimg.com/ca/I/stylespilotshop_2073_389963466

[Rod Sheridan]

Hi Gary, a template could be attached to the plywood with double sided tape, and then a router could trim it to final size.

Regards, Rod.

[mickey cassiba]

+1 on the fly cutter. Also called a "trepan" (not sure of the spelling). The beam can be replaced to make almost any size hole. I've used them to cut REALLY big holes in all types of metal, and, when I get the woodworks going, expect to use them again. Really large diameters are aided by an outrigger opposite the cutting knife. Basically a bearing on the other end of the bar that will keep the knife from deflecting out and making a tapered cut
Mickey
Trying to get my Sketchup chops up to illustrate.

[Paul Ryan]

I was one of those fools that bought a roto zip when they came out. Acually I have a craftsman version. It came with a whole slew of attachments. One of the attachments happens to be a circle cutting jig. That tools is worthless except for that jig. I have found nothing that works better for cutting perfect larger circles (bigger than a hole saw). If you can find one of those it is really slick. Drill a hole in the center plunge your bit and turn the tool, slick.

[John Terefenko]

Why not a router??? Use double sided tape to hold template. Have to cut a template though but that is easy with a bandsaw or scrollsaw. You do not want to pay for a 6 inch hole saw. Or you can use a router with a circle cutting jig.

[Myk Rian]

I would also have suggested carpet tape to hold a router template, but I have had it tear out plywood when removing it. That is Garys' concern.
A router with a circle jig would also work well. I use them often.

[Bill Huber]

I say use a router, make the circle in MDF or the like and then tape it down.
Put a trim bit in with the bearing on bottom and go for it.

The best tape that I have found is from Eagle, it comes off clean and also hold very well.

http://www.eagleamerica.com/product/v447-7150/adhesives

[James Baker SD]

Starrett and Milwaukee both make 6" hole saws so they are available on Amazon. Kind of pricey though unless you will use it many times.

James

[Paul Atkins]

Although I've used double stick tape for the jig described I would think a bit here. The tape I have might rip the veneer right off . I make an oversized pattern with a hole in the middle and clamp it where I need it -no glue, nails, or tape residue. This way you can cut a hole about any where and any size. The fly cutter would be limited to the size of drill press (shaft to hole) and not as clean. Sometimes I make a template on the lathe first to make the hole on a bigger board.

[Josiah Bartlett]

Starrett and Milwaukee both make 6" hole saws so they are available on Amazon. Kind of pricey though unless you will use it many times.

James

You need a lot of power out of a drill to use a big hole saw like that. I nearly broke my wrist when using a 4" holesaw when it caught, I would hate to see what a 6" would do. A fly cutter is a good option, or a router template.

[Tom Veatch]

You need a lot of power out of a drill to use a big hole saw like that. I nearly broke my wrist when using a 4" holesaw when it caught, I would hate to see what a 6" would do. A fly cutter is a good option, or a router template.

A fly cutter is an option if it can be done with a drill press or similar machine. I don't think it even comes close to being an option if the tool is a hand held drill motor. Likewise, I don't think a 6" hole saw is a hand held option.

Router and template if the hole location in the sheet can't be reached with a drill press. Hog it out with a saber saw and clean up with router and template.

[John Coloccia]

If you're worried about damaging the plywood with tape, I would use the template to make a hole in some scrap, and then clamp that to the sheet as your new template. Use a trim bit with a bearing and cut. Alternately, use the trim bit to duplicate the template, and then use the collar to make the hole.

That's probably what I'd try first because it seems simple, and I'm lazy :)

[Kent A Bathurst]

Starrett and Milwaukee both make 6" hole saws so they are available on Amazon. Kind of pricey though unless you will use it many times.

James

I had a need, and got a couple hole saws (Starrett), with the removeable arbor. After that initial investment, I get an additional saw as/when the need arises.

[John Coloccia]

One thing to remember with the fly cutter. Wait until it stops turning BEFORE you reach for the part. I know it's obvious, but just keep saying this to yourself as you shutdown the drill press. Guaranteed you will catch yourself from mangling your hand someday. The instinct to shut off the press and grab the part is really deeply ingrained. I've caught myself twice thanks to my fly cutter mantra.

[john bateman]

Get one of these "Jasper Jigs" and attach to your router. If you don't think you'll need it again in the future, you can make an oversized router baseplate from scrap hardboard, and drill the pivot point so that it will give a 6" circle.

http://images.rockler.com/rockler/images/63430-01-500.jpg

[Doug Shepard]

... you can make an oversized router baseplate from scrap hardboard, and drill the pivot point so that it will give a 6" circle.



My first circle jig was nothing more than a 6" wide strip of hardboard mounted to the base of the router. Drill a 1/4" hole in the center of your hole location, stick a dowel 3" from the far side of the router bit through the hardboard and into the hole in the ply and start turning.

[Prashun Patel]

I say use a router, make the circle in MDF or the like and then tape it down.
Put a trim bit in with the bearing on bottom and go for it.

The best tape that I have found is from Eagle, it comes off clean and also hold very well.

http://www.eagleamerica.com/product/v447-7150/adhesives

Thanks for this tip, Bill. Thanks for all yr tips!

[Zach England]

Jasper jig.

[John Coloccia]

While the router mounted circle jigs are great for making round discs, I have to think it's very easy to mangle the cutout. There's nothing keeping the disc/router from drifting into the sheet as you finish the cut. Is it just a matter of being careful, or is there a trick for getting the cutout to come out perfectly?

[Lee Schierer]

Although I've used double stick tape for the jig described I would think a bit here. The tape I have might rip the veneer right off .

The trick with double sided tape is use enough to do the job but not too much and most importantly don't leave it stuck any longer than needed to get the job done. In most cases, the longer tape is on a surface the tighter it grips. Don't place any tape near a cut edge and always peel the tape off toward the cut edge not away from it.

[Wayne Cannon]

A fly-cutter catch is worse than a hole-saw catch.

I've never had a problem using a large hole saw, even with a modest drill, as long as you don't lean on it. I wouldn't expect a cordless drill to do very well, however. Keeping the RPM up will minimize any tendency to catch.

Having said that, 6" is a reasonable size to cut with a router, as well. A router will take longer to set up and cut, but you will get a cleaner hole.

[Tom Veatch]

While the router mounted circle jigs are great for making round discs, I have to think it's very easy to mangle the cutout. There's nothing keeping the disc/router from drifting into the sheet as you finish the cut. Is it just a matter of being careful, or is there a trick for getting the cutout to come out perfectly?

Awhile back, I had several circle cutouts to do and was concerned about that exact problem. My solution was to use a piece of plywood larger than my workpiece, drill and insert a 1/4" dowel at the center of the plywood, attached an auxillary block with a 1/4" through hole to the router's edge guide.

A 1/4" hole at the center of the cutout in the workpiece fit over the 1/4" dowel in the plywood base, and the hole in the edge guide fit over the dowel on top of the workpiece. Edge guide adjustment set the radius of the circle. Clamped the workpiece to the plywood base, routed the circle. Clamp restrained the workpiece, dowel restrained the center cutout, plywood base protected my workbench. Use the same tooling for every circular cutout larger than my router baseplace.

[Bob Stritzke]

Awhile back, I had several circle cutouts to do and was concerned about that exact problem. My solution was to use a piece of plywood larger than my workpiece, drill and insert a 1/4" dowel at the center of the plywood, attached an auxillary block with a 1/4" through hole to the router's edge guide.

A 1/4" hole at the center of the cutout in the workpiece fit over the 1/4" dowel in the plywood base, and the hole in the edge guide fit over the dowel on top of the workpiece. Edge guide adjustment set the radius of the circle. Clamped the workpiece to the plywood base, routed the circle. Clamp restrained the workpiece, dowel restrained the center cutout, plywood base protected my workbench. Use the same tooling for every circular cutout larger than my router baseplace.

Thanks I like this idea.

[John Coloccia]

Awhile back, I had several circle cutouts to do and was concerned about that exact problem. My solution was to use a piece of plywood larger than my workpiece, drill and insert a 1/4" dowel at the center of the plywood, attached an auxillary block with a 1/4" through hole to the router's edge guide.

A 1/4" hole at the center of the cutout in the workpiece fit over the 1/4" dowel in the plywood base, and the hole in the edge guide fit over the dowel on top of the workpiece. Edge guide adjustment set the radius of the circle. Clamped the workpiece to the plywood base, routed the circle. Clamp restrained the workpiece, dowel restrained the center cutout, plywood base protected my workbench. Use the same tooling for every circular cutout larger than my router baseplace.

This is a nice, simple solution.

[Phillip Marsh]

The reason they don't make hole saws larger than 6-1/4" is that the torque required to drive them is well beyond the capabilities of any hand held drill. Even the mighty Milwaukee Hawg stud drills are rated for a maxium hole saw size of 4-5/8 in wood.

We use a Hole Pro adjustable hole cutter that we first saw on "Cool Tools" and with it we can easily cut 12" diameter holes in MDF and plywood using a 1/2" hand drill with now problems and get a much cleaner hole in a lot less time as well. Twin blades make for less contact area so a lot less horsepower is needed and their is no burning of the wood and you won't spend another 5 minutes knocking out the plug when you are done.
Good for laminates and plastics as well and no worry about needing an ultra low speed to prevent melting as with hole saws and similar tools.

You can also make the hole exactly the size you really need, 6-1/4, 6-3/8, 6-7/16, no problem. But use a twin blade cutter as the single blade tools are not very good and are very limited in their cutting range. We usually use the Hole Pro model X-305 that adjusts infinitely from 1-7/8" up to 12" as we do speaker and home theater cabinetry and are often working with MDF (which rapidly dulls bi-metal hole saws).

[John Coloccia]

I have the need to cut several 6" holes in sheets of hardwood plywood.
What is the best way of cutting such an hole? Is there a 6" hole saw? The problem I see with a router is mounting a template without damaging the plywood.

By the way, I was at my local Home Depot the other day, and they sell 6" Ridgid hole saws. It's about $40. Glad someone resurrected this thread...I almost forgot.