How to make a 60mm hole

[mjmjm]

I've been on the planet for many years, but I've never learned how to successfully make a 60mm hole in wood.

I want to mount some weather instruments.

I bought a set of hole saws, the ones with different size blades that fit into a slotted holder, but the wood grabbed it and ripped it and the drill out of my hands, bending the mandrel in the process.

I figure there must be a better way to do it. Only way I can think of is a dedicated 60mm saw in a drill press. Can anyone give some advice?

Michael

[warrick]

Make a template and use a router

Warrick

[weisyboy]

a jigsaw and a smaller drill bit?

[rrich]

Make a template and use a router

Warrick

That's not fair. :)

You probably need to start with a hole that can be enlarged with a rabbetting bit. Two templates, each one enlarged with the rabbet bit. The trick is to start with a hole that can be enlarged in a number of twice the size if the rabbet.

[Al B]

Michael What about a 60mm Forstner Bit.

http://www.mcjing.com.au/woodworking/forstner/forstner.ASP

[AUSSIE]

Michael What about a 60mm Forstner Bit.

http://www.mcjing.com.au/woodworking/forstner/forstner.ASP
Michael
I have the good holesaw & the router & the Forstner Bit.Along with the drill press needed.
Pick the Forstner Bit in the bench drill every time.
You will get a nice clean hole,not a lot of mess
Clamp your wood ,Dont forget a nice flat board under your job,set drill to a slow speed and feed the forstner bit down slowly.You will be finished in no time and be very pleased with yourself.
Aussie

[coffenup]

use your mother inlaws mouth . mine chewed me so much I recon my hole is at least that large:D:D:D

[Skew ChiDAMN!!]

I'd use a forstner bit if a drill press is available.

Otherwise I'd use a dedicated 60mm. hole saw... the type with a separate arbor, to accept different dia. blades. (Not the type that fit into concentric slots! [shudder])

Purely because a forstner is more likely to grab when freehanding than the hole saw and also tends to be slower. It removes way more material after all!

[STAR]

I recently made a weather station and purchased the correct Forstner bit to go with them. the result was a perfect fit.

Not sure if it was a fifty or 60 mm hole but the cost was only $15. I will not buy a clock now unless I can get a matching forstner bit.

I got my Forstner bit from letsmaketime.com.au Janine is on the Gold Coast but I am sure you can get them elsewhere and look after them.

[China]

The hole saws that fit into slots like the one you used are complete rubbish as Skew said buy a good quality hole saw and the diference will be like chalk and cheese, good hole saws will set you back around $30.00 each, the cost is well worth it, also take easy and let the saw do the work

[mjmjm]

Thanks for all the replies. I'll de-rust the drill press that's been sitting on the verandah for years and get a 60mm bit.

Michael

[munruben]

I bought a set of hole saws, the ones with different size blades that fit into a slotted holder, but the wood grabbed it and ripped it and the drill out of my hands, bending the mandrel in the process. Gotta use a drill press with those things.


I'll de-rust the drill press that's been sitting on the verandah for years and get a 60mm bit.Way to go :2tsup:

[Scally]

The drill press and forstner bit is the way to go.

Clamp your board down on the drill press table and drill slowly so you don't burn the bit.
Put a waste piece under the work piece if you intend to cut the hole all the way through.


I have been cutting a lot of circles lately for making drums and I also made a weather wall with different size clocks/gauges.

Sometimes you just can't find the exact size drill/hole-saw.

I made a couple of bases for my router.
One is like a long tramel with hole drilled along the arm. It has predrilled holes for set diameters.
The pic shows a fancy version that you can buy.

Sometimes I make the tramel or base out of MDF or perspex and drill a hole exactly where I need it for the circle.

I did make a perspex base with an "adjustable centre pin hole".
I found the plan in a Router Jig book by Patrick Spielman.

Router Jig and Techniques, Page 194, Adjustable Circle Cutting Base.
His example cut holes from 1" up to 7". Pretty handy.

It is very handy because you can slide the centre-pin along the arm to get the exact diameter you want and you can use any size bit you like.

Have a look at this one from the Forum
http://www.woodworkforums.ubeaut.com.au/showthread.php?t=15808

If you like to spend more time making jigs than jobs - you might like this link.
http://www.woodcraft.com/articleprint.aspx?ArticleID=618
It explains how to make an adjustable circle cutting jig.


Cheers

[scotty60]

i do it the easy way , i have a waterjet at my work,it cuts what ever you want:2tsup:

[Barry_White]

When drilling a large hole with a holesaw a tip is to drill about a 10mm hole just right on the edge of the 60mm hole. This allows the sawdust to clear down the 10mm hole and not clog up the teeth on the hole and will prevent burning as well.

This is especially important when drilling MDF.

[mjmjm]

Never thought of that. Thanks.
Michael

[AUSSIE]

When drilling a large hole with a holesaw a tip is to drill about a 10mm hole just right on the edge of the 60mm hole. This allows the sawdust to clear down the 10mm hole and not clog up the teeth on the hole and will prevent burning as well.

This is especially important when drilling MDF.
That is a great tip Barry.Simple when you think of it.
Aussie