CUTTING A CIRCLE WITH A ROUTER

[user 19915]

OK here we go just a quick question im going to cut a wooden circle using a router in plywood to start and then in other timber so my question is what router bit should i use to plunge and cut a circle in plywood ??And if in other timber should i change the bit if so to what ???
thank.s in anticipation mock

 

[paulm]

Just a normal two flute straight cutter would work fine. You can get up or down spiral cutters too for particular applications but I would try a normal basic cutter first.

Cheers, Paul

 

[paulm]

If you are following a template then choose one with a bearing on top or bottom to suit.

Cheers, Paul

 

[Phil Pascoe]

Try "Wealden" for mail order cutters - they're hard to better.

 

[Stu_2]

I use a Trend CRB, and Axminster cutters. They do a limited a range of bottom-cutting bits, which are a good all-rounder for this application. Axminster cutters are excellent.

 

[user 19915]

What about carving your name on a project would there be a specific bit

 

[Phil Pascoe]

Any small "V" cutter, I would think. You'd need a bit of practice to do them freehand.

 

[user 19915]

Yes and iv,e never used a router before that why all the questions lol
thank,s Phil

 

[MIGNAL]

I once cut a circle in plywood with a router.
I got a bit of a surprise when I did the final pass. Something started juddering violently at roughly 10,000 RPM or so. :roll:

 

[user 19915]

What did you make that

 

[MIGNAL]

It was a warning. Don't cut a circle in the middle of a piece of plywood. At least not where the central portion is small and free to jingle about just after you have plunged right through, thus 'releasing' it. There are safer ways to do it.
If you are new to routers just make sure you know the safety aspects and the pitfalls.
I just gave up using routers. :shock:

 

[user 19915]

Thank,s for the warning im always open for suggestions as you can tell im new to wood work the circle i cut was 13in :idea: (hammer)

 

[jimmyhenson]

If you cut out the circle a few mm oversize with a bandsaw or jigsaw it will be safer and quicker to router

 

[custard]

If you cut out the circle a few mm oversize with a bandsaw or jigsaw it will be safer and quicker to router

+1

And the finish will likely be better too.

 

[Skeety]

In my limited experience screw the centre and outer to a sacrificial bit of timber so they don't move when you do the final pass. I also use a Trend CRB like Stu_2. If you are really new to it I would advise practicing on some off cuts. I used a 6mm x 20mm cutter to radius a shelf tonight, 18mm at full depth but made 4 passes and was perfect.

Key thing here is make sure neither part can move and don't try going through in 1 pass, do several which will give you a better finish. Before you start for real do dry passes to make sure nothing is in the way and helps you get used to the router.

Jon.

 

[rafezetter]

if you are cutting right through then either small tack pins or double sided tape on each bit both inner and waste will stop any mad issues when it finally releases the 2 parts.

 

[Eric The Viking]

A couple of years ago, I tried to make a jig for cutting small circles out on a router table. The design brief was no central hole, as for the purpose that wasn't acceptable.

I very nearly made it work. Presently, it doesn't, so I've had to cancel the book launch and open-topped bus parade through Bristol city centre. Humiliating, but research will proceed, and we WILL have victory eventually.

The US military have expressed an interest though, as it uses far less energy than their new railgun and the results are roughly comparable. Meanwhile, I am learning when to duck and feeling is slowly returning on that side.

Don't let my temporary setbacks put you off though. With a suitable helmet, visor and Kevlar body armour it's perfectly safe, as long as you keep your fingers out of the way, of course.

Don't forget Alfred Nobel's famous saying, "If nobody experimented, we'd probably still have all our fingers, eyesight and hearing."*

E.

*OK, I may have misheard that at some point. Parden?

 

[rafezetter]

A couple of years ago, I tried to make a jig for cutting small circles out on a router table. The design brief was no central hole, as for the purpose that wasn't acceptable.

I very nearly made it work. Presently, it doesn't, so I've had to cancel the book launch and open-topped bus parade through Bristol city centre. Humiliating, but research will proceed, and we WILL have victory eventually.

The US military have expressed an interest though, as it uses far less energy than their new railgun and the results are roughly comparable. Meanwhile, I am learning when to duck and feeling is slowly returning on that side.

Don't let my temporary setbacks put you off though. With a suitable helmet, visor and Kevlar body armour it's perfectly safe, as long as you keep your fingers out of the way, of course.

Don't forget Alfred Nobel's famous saying, "If nobody experimented, we'd probably still have all our fingers, eyesight and hearing."*

E.

I have JUST the thing for you give this a whirl *ahem*.... - read all of it,as all will become clear

http://www.woodcraft.com/Articles/Articles.aspx?articleid=618

I can also help get you the plexiglass.

 

[Phil Pascoe]

I like the "now use your jig to make a ... jig".

 

[rafezetter]

I like the "now use your jig to make a ... jig".

true - It's not ideal, but the first jig would only work with a central hole and cut only larger circles, the smaller one gives you the ability to cut almost tiny circles with no central hole, which is what Eric was after.