# 2-3/4" Holes in Plywood



## patlaw (Jan 4, 2010)

I have to cut a number of 2-3/4" holes in 3/4" plywood. The options I'm considering are a Forstner bit, a hole saw, or an adjustable hole cutter, as in the picture below. The reviews on all of these products are all over the place. The Forstner bits look like they will dull quickly in plywood. Hole saws are slow to cut, but they're pretty durable. I've never used a hole cutter. For the record, I don't know how to sharpen bits, so I'd like to know which bit will last the longest. The hole cutter has a lot of appeal because it is infinitely adjustable. Which way should I go?


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## Nickp (Dec 4, 2012)

Forstner bit will tear at the bottom...
Circle cutter might also...and will grab as grain changes...not really meant for deep cuts...
Hole saw has my vote...

Drill press...?


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## Stick486 (Jan 4, 2013)

have the hole cutter...
not so good...

better forstner bits w/ serrated/toothed rims and an in carbide will outlast you...

1 to 4 tooth hole-saws (Lenox or Bosch) are for wood...
mega toothed saws are for metal but will do wood...
these saws are everywhere...


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## Stick486 (Jan 4, 2013)

Nickp said:


> *Forstner bit will tear at the bottom...*
> Circle cutter might also...and will grab as grain changes...not really meant for deep cuts...
> Hole saw has my vote...
> 
> Drill press...?


serrated bit and a backer will put a stop to that...


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## phillip.c (Aug 9, 2012)

Forstner bit is your best bet. You can place a sacrificial piece under your work to prevent tear out. 

Hole cutters are clunky to set up and run. You'll get some variation in your diameters. I have one that dulls very quickly. A forstner bit will last a long while.


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## JIMMIEM (Apr 4, 2010)

RotoZip type tool will also work. It's a specialized tool so not something you'd want to buy for a one-time project. How large are the pieces that you need to cut the holes in?


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## patlaw (Jan 4, 2010)

Yes, I have a drill press. There are 12 holes in a 16x20 piece of 3/4" plywood.


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## Stick486 (Jan 4, 2013)

fostner...


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## JIMMIEM (Apr 4, 2010)

Make a template. Rough cut the holes and finish with a flush trim bit in a router.


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## dalboy (Jun 12, 2012)

JIMMIEM said:


> Make a template. Rough cut the holes and finish with a flush trim bit in a router.


I would go this route as well, as I feel it would leave cleaner holes


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## tomp913 (Mar 7, 2014)

Make a template. Cut the hole using a router with a template guide, size the hole in the template to suit the required finished hole size, bushing diameter and router bit.


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## patlaw (Jan 4, 2010)

The router is a fourth option I didn't consider. It makes sense to me, and it will save the Forstner bit, but it's a lot more work. Thanks for the suggestions. 

Is a $45 Forstner bit worth twice as much as a $22 bit?


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## Stick486 (Jan 4, 2013)

got a bit link???


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## JIMMIEM (Apr 4, 2010)

patlaw said:


> I have to cut a number of 2-3/4" holes in 3/4" plywood. The options I'm considering are a Forstner bit, a hole saw, or an adjustable hole cutter, as in the picture below. The reviews on all of these products are all over the place. The Forstner bits look like they will dull quickly in plywood. Hole saws are slow to cut, but they're pretty durable. I've never used a hole cutter. For the record, I don't know how to sharpen bits, so I'd like to know which bit will last the longest. The hole cutter has a lot of appeal because it is infinitely adjustable. Which way should I go?


FWIW, you can buy replacement bits and the cutter for the hole cutter that you have pictured. I've been able to cut clean holes in plywood using this tool. Based on the size of your sheet would you be able to reach all the hole positions if you used a drill press?


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## jd99 (Jun 17, 2009)

I like the router method, Ive used the hole cutter several times have even used it on metal, (Look up Trepanning) the main thing on the hole cutter is 
Your bit needs to be sharp, and make sure there is enough back clearance to clear the radius of the hole.
The material your cutting has to be clamped down and not move.
the spindle on your drill press should not move side to side, or wobble.


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## Herb Stoops (Aug 28, 2012)

To make the template you will have to cut holes with something the same size or larger than the finished hole. Depending on if you are using a bushing on the router, or a bearing. That is almost too big for a drill press so a template is the best way to go.

Be sure to cut the center out of the hole before routing out the last 1/8".

Herb


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## patlaw (Jan 4, 2010)

Stick486 said:


> got a bit link???


Steelex Forstner Bit $20.60

Roman Carbide Forstner Bit $44.95


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## Herb Stoops (Aug 28, 2012)

Another suggestion is to drill a small pilot hole all the way thru and then use a forstner bit to drill from both sidea, that would solve the tearout problem.

Herb


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## JIMMIEM (Apr 4, 2010)

Herb Stoops said:


> To make the template you will have to cut holes with something the same size or larger than the finished hole. Depending on if you are using a bushing on the router, or a bearing. That is almost too big for a drill press so a template is the best way to go.
> 
> Be sure to cut the center out of the hole before routing out the last 1/8".
> 
> Herb


Hole cutter to make the template from mdf.


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## Stick486 (Jan 4, 2013)

patlaw said:


> Steelex Forstner Bit $20.60
> 
> Roman Carbide Forstner Bit $44.95


those two bits are not in the same league w/ each other...
the Freud will outlast the Steelex by a wide margin...

HSS vs carbide...


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## patlaw (Jan 4, 2010)

Stick486 said:


> those two bits are not in the same league w/ each other...
> the Freud will outlast the Steelex by a wide margin...
> 
> HSS vs carbide...


Understood. I did order the cheaper one. I'll use it to make the template for the router. I'm not sure if the drill press will allow me to get to the center holes. Using the router will give me a chance to use one of the jig saws, which I haven't touched in years.


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## Stick486 (Jan 4, 2013)

use a Top Bearing Flush Trim Router Bit nd you'll be golden...


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## hawkeye10 (Jul 28, 2015)

JIMMIEM said:


> Make a template. Rough cut the holes and finish with a flush trim bit in a router.


""Bingo"" Jim gets my vote with his idea.


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## patlaw (Jan 4, 2010)

Stick486 said:


> use a Top Bearing Flush Trim Router Bit nd you'll be golden...


The Whiteside 3004 will be here tomorrow.


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## Stick486 (Jan 4, 2013)

patlaw said:


> The Whiteside 3004 will be here tomorrow.


excellent..


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## JIMMIEM (Apr 4, 2010)

Stick486 said:


> use a Top Bearing Flush Trim Router Bit nd you'll be golden...


Would he be Silver if he used a Bottom Bearing Flush Trim Router Bit and did the routing on a Router Table?


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## Stick486 (Jan 4, 2013)

more control free hand because of the clamping you'll do on the work piece....


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## chessnut2 (Sep 15, 2011)

Herb Stoops said:


> Another suggestion is to drill a small pilot hole all the way thru and then use a forstner bit to drill from both sidea, that would solve the tearout problem.
> 
> Herb


That's what I do on most all forstner cuts.


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## mgmine (Jan 16, 2012)

For 12 holes I would go with a hole saw. The fly cutter you pictured would also work but should be used in a drill press and they can be dangerous. The last tool I would drag out would be a router. By the time you have a template made you could have drilled all the holes several times over.


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## cocobolo1 (Dec 31, 2015)

I recently needed to cut several 2 9/16" holes in 3/4" plywood.

I used a sawtooth bit from Lee Valley along with a backer board on both top and bottom of the plywood.

Zero tearout anywhere, and the job took but a few minutes.


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## jw2170 (Jan 24, 2008)

Use one of Harry's circle cutting jigs....

Easy, Peasy....

http://www.routerforums.com/jigs-fixtures/28939-building-harrys-simple-circle-jig.html

Or one of theses..

http://www.routerforums.com/jigs-fixtures/581-router-cutting-circles.html


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## patlaw (Jan 4, 2010)

Well, I just ordered the Forstner bit....


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## billyjim (Feb 11, 2012)

patlaw said:


> I have to cut a number of 2-3/4" holes in 3/4" plywood. The options I'm considering are a Forstner bit, a hole saw, or an adjustable hole cutter, as in the picture below. The reviews on all of these products are all over the place. The Forstner bits look like they will dull quickly in plywood. Hole saws are slow to cut, but they're pretty durable. I've never used a hole cutter. For the record, I don't know how to sharpen bits, so I'd like to know which bit will last the longest. The hole cutter has a lot of appeal because it is infinitely adjustable. Which way should I go?


Forstner is my choice. Back it up and you will have no problems.


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## Herb Stoops (Aug 28, 2012)

patlaw said:


> Well, I just ordered the Forstner bit....


You will need a 1/2" drill motor to drill with a Forstner bit,if not using the drill press.

Herb


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## bwilling (Jul 14, 2015)

chessnut2 said:


> That's what I do on most all forstner cuts.


When I use a forstner bit I drill nearly thru until the pilot point just comes thru than turn the stock over and using the bits pilot hole as a guide drill the remainder thru. No tear out.


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## john60 (Aug 30, 2014)

I would use the following since I already own one. Works great for this application



The CRB7 arms your router with the ability to cut fully microadjustable dadoes, mortises, circles, and indexed grooves for faux paneling and shelving systems. (Clamp Guide Not Included)





In addition to that, the offset design provides excellent anti-tilt support, and includes an accessory support foot for routing narrow materials.

The CRB provides a simple and exceptionally quick way of accurately repeating a dado for indexed grooves in shelving systems and false panelling. 

The CRB7 fits the majority of woodworking routers, and unlike similar jigs, it requires no screws or drivers to install, just slide it on and tighten the knobs.

Increased stability in turn leads to better accuracy and finish quality.

Use the magnetic pin stored in the base to rout precision circles and holes, even holes that are actually smaller than the base of the router! 

Realize the full potential of your router in only seconds with the easy-to-install CRB7 Multi-Function Router Base.
.
Previous


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. 

See it in action:


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MPower Combination Router Base - Overview 


MPower Combination Router Base - In-Depth 


Micro-Adjust Your CRB7 Router Base 


Enhance Your Router with M-Power 
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M-Power CRB7 MK3 Multi-Function Router Base


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## Stick486 (Jan 4, 2013)

John, no links....


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## boogalee (Nov 24, 2010)




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