some basic routing guidance needed - cutting rectangles

[sramdeen]

Hi all. This is my first post after having found this site whilst googling. I have a kitchen worktop in 40mm oak and need to cut three rectangles in it. To give you a rough idea of the size, the worktop is 2 metres long by 60cm wide. The rectangles are going to be about 36cm x 46cm each, in the middle of the worktop, with about a 3-5cm gap between each cutout.

What is the best way to go about this? Is routing the correct way to tackle this problem? I have enquired about getting it done professionally via a cnc machine shop not too far away but they want to charge a three figure sum. I would like to be able to do this myself and if it means making an investment in a piece of kit, I don't mind as I will probably need to use it again in the future.

The only problem I can see with cutting it with a router is that I'll be left with curved inner corners. The corners need to be straight cut, as if they were cut with a jigsaw, but with the accuracy of a router.
I was thinking about setting up some guides so that I could run my jigsaw along the guides and therefore should end up with a pretty straight cutout, but being that the worktop is 40mm thick, I don't think the cut would be completely square (speaking from previous, bitter experience...)

If I go the router route, I would need to obtain the smallest diameter template-bit available to minimise the curve of the corners (smallest one I can find is 1/4", same as my router's chuck). Still, any curvature at all is not desirable. If my limited research is correct, I would need to fabricate some guides, or a frame, so that the router may 'run around' the frame to obtain a perfect, 'square' cutout. Do you agree with this, or is there a better way. If I go this way, how do I fix the frame to the worktop; I can't nail it on as that would then ruin the worktop.

Many thanks for your advice.

Stuart

[Tex B]

Stuart,

I wouldn't want to try routing holes in a 40mm solid timber. Even getting bits that will go to that depth is not easy or cheap, and would definitely take several passes, like five or six.

Instead, buy a good jigsaw, should be a bit cheaper than a router as well, and buy a couple of extra blades.

The trick, whether you're using a router or a jigsaw, is to clamp a straight edge the proper distance from the cut so the the tool runs up against the straight edge.

Most people cutting holes in kitchen counters are installing sinks, stoves, etc, which have a lip that covers the edge and hides any irregularities in the cut. Means the corners are not so critical and don't need to be exactly square. If you're doing something different, might consider some kind of moulding so you can cover the actual cut.

Tex

[HarryM]

G'day,

I also wouldn't recommend a router for this task. I would suggest you consider drilling four through holes using a spade bit, then using a bandsaw cut out the rectangles.

Of course you need access to a friend or a woodworking group who has a band saw, or else the money you save from the quote you got, buy a bandsaw, they are not that expensive.

I hope it helps.

Regards,

HarryM

[ozwinner]

I would use a jig saw too, or a circular saw for the bits in between the corner drill holes and finish off with a hand saw.

Al :)

[echnidna]

I'd use a circular power saw and cut out the corners with a handsaw

[Shedhand]

Welcome Sramdeen.
I'd use a Circular saw (60t or more to reduce tearout) to cut the bulk of the length of all sides (clamp a piece of hardwood or straight edge to the bench as a guide for the saw) then I'd finish the cuts to the corners with a Jap saw (they cut on the pull stroke and easier to get an accurate and square inside corner.
Good luck with it;)

[NewLou]

Gidday Sramdeen:)

Just trying to get my head round why the rectangles need to be perfectly square? Usually these kinds of cutouts arn't required to be super accurate for kitchen installations??????

Regardless due to the size of the rectangles your cutting I'd tend to lean towards the following:

1. Drilling holes with a brad or forstner bit in the corner of your rectangles (Bit size you choose will dictate cleanup to square corners)

2. Rough cut rectangle out with a quality Jigsaw

3. Tidy up your rectangles with a flush trim bit (bearing type) or straight bit using a template guide.

4. You could square the corners with a handsaw or sharp chisel. Score your markout line to help ensure squareness.

As always though pleanty of options to choose from.

Regards lou :)

[Greg Q]

Beat me to the answer, New Lou. I was just reading the rest of the thread-you saved me a bit of typing.

Greg

[Shedhand]

Yep, NewLou's plan is the go.;)

[doug the slug]

Gidday Sramdeen:)

Just trying to get my head round why the rectangles need to be perfectly square? Usually these kinds of cutouts arn't required to be super accurate for kitchen installations??????

Regardless due to the size of the rectangles your cutting I'd tend to lean towards the following:

1. Drilling holes with a brad or forstner bit in the corner of your rectangles (Bit size you choose will dictate cleanup to square corners)

2. Rough cut rectangle out with a quality Jigsaw

3. Tidy up your rectangles with a flush trim bit (bearing type) or straight bit using a template guide.

4. You could square the corners with a handsaw or sharp chisel. Score your markout line to help ensure squareness.

As always though pleanty of options to choose from.

Regards lou :)

definitely the way to do it Lou

[Template Tom]

Hi all. This is my first post after having found this site whilst googling. I have a kitchen worktop in 40mm oak and need to cut three rectangles in it. To give you a rough idea of the size, the worktop is 2 metres long by 60cm wide. The rectangles are going to be about 36cm x 46cm each, in the middle of the worktop, with about a 3-5cm gap between each cutout.

40mm thick would rule out the use of the router unless you were to use a 16mm long reach cutter and work in stages

What is the best way to go about this? Is routing the correct way to tackle this problem? I have enquired about getting it done professionally via a cnc machine shop not too far away but they want to charge a three figure sum. I would like to be able to do this myself and if it means making an investment in a piece of kit, I don't mind as I will probably need to use it again in the future.

The only problem I can see with cutting it with a router is that I'll be left with curved inner corners. The corners need to be straight cut, as if they were cut with a jigsaw, but with the accuracy of a router.

Here you will always have a radius in each corner in this instance 8mm which will have to be chissed square.

I was thinking about setting up some guides so that I could run my jigsaw along the guides and therefore should end up with a pretty straight cutout, but being that the worktop is 40mm thick, I don't think the cut would be completely square (speaking from previous, bitter experience...)
Yes the cut is never square cutting into 40mm material (Average Jig saw Blade)

If I go the router route, I would need to obtain the smallest diameter template-bit available to minimise the curve of the corners (smallest one I can find is 1/4", same as my router's chuck).
You will never get a cutter long enough to fit into a 1/4" chck (Safety reasons)

Still, any curvature at all is not desirable. If my limited research is correct, I would need to fabricate some guides, or a frame, so that the router may 'run around' the frame to obtain a perfect, 'square' cutout. Do you agree with this, or is there a better way.

This will still give a radius corner irrispective of what frame you use but this is the way to do it with a longer 1/2" cutter such as the 16mm
If I go this way, how do I fix the frame to the worktop; I can't nail it on as that would then ruin the worktop.

Make one of the sides of the frame wider so that you can clamp it to the bench with at least two clamps

Many thanks for your advice.

I hope this is of some Guidance
Tom

Stuart

[doug the slug]

Hey, Tom

CHeck the dates beforee replying - if he hasnt already done it i doubt if he's going to do it at allhttp://www.woodworkforums.ubeaut.com.au/images/icons/icon10.gifhttp://www.woodworkforums.ubeaut.com.au/images/icons/icon10.gifhttp://www.woodworkforums.ubeaut.com.au/images/icons/icon10.gif

[Auld Bassoon]

Hey, Tom

CHeck the dates beforee replying - if he hasnt already done it i doubt if he's going to do it at allhttp://www.woodworkforums.ubeaut.com.au/images/icons/icon10.gifhttp://www.woodworkforums.ubeaut.com.au/images/icons/icon10.gifhttp://www.woodworkforums.ubeaut.com.au/images/icons/icon10.gif

:D