Simple circle jig

[AntonZ]

I posted this inside another thread. Apparently people liked the idea, so I figured it might as well be posted in the Tips/Techniques section where it does not expire automatically.

Here's my scrap wood circle jig. I use it for baffle holes, recessed circular cuts and the like. The router is the cheapest I could find, about 35 euro's. The router is working fine for me, though I do have to check regularly for screws coming loose.






It uses metal for the point where it turns rather than just a hole in the wood, so it will retain precision much longer. The threaded thingies are made out of long threaded rods (sold per meter, don't know the name in english) instead of the rods from the parallel jig that came with the router (I want to use that jig as well at times). Because a router gives strong vibrations, I used self-blocking nuts (with the nylon ring in it, don't know what these are called in english either). The 3mm bolt for centering is stored in a 3mm hole in the jig when it is not being used.

[David Carter]

This is an excellent idea! Thanks for sharing! Now I just have to get a router!

[spiderbass]

Really nice idea, thanks

[Harley]

Anton, that's a great simple tool jig and I am going to build myself one or two of those

For your info;

The threaded thingies are made out of long threaded rods (sold per meter, don't know the name in english)

They are called 'threaded rods'

I used self-blocking nuts (with the nylon ring in it, don't know what these are called in english either).

They are known as "Nylock Nuts"

[AntonZ]

Thanks for the thumbs up for both the jig and my english (I'm not a native speaker )

Additional recommendations:
Use thin plywood for the jig's base if you intend to "go deep" (like cutting baffle holes in 3/4" ply or more). You need quite a long router bit if the jig is 1/2" and the baffle is like 3/4". My version cuts through 1/2" ply with a regular router bit, 3/4" would be somewhere between tricky and impossible. The adventurous might let the router bit extend a little more, I find this far too dangerous with bits rotating at anywhere between 10.000 and 30.000rpm in a $35 router and therefore strongly advise against any experiments in that direction.

Most routers allow to remove their plastic base, which might give those few extra mm's needed to cut through.


Harley, since you are the unofficial "master of jigs" on this forum, please do not hesitate to share any improvements you make.

[Harley]

Harley, since you are the unofficial "master of jigs" on this forum, please do not hesitate to share any improvements you make.

I think Tim deserves a fair share of that title too! He's come ups with a few beauts.

I'm picking he must have been a bass player at some stage.

[bgavin]

I'm picking he must have been a bass player at some stage.

Even if he was, there is no salvation for Tim now. He has gone over to the Dark Side now.

[Harley]

Even if he was, there is no salvation for Tim now. He has gone over to the Dark Side now.

I might try and invoke a miracle by attempting born again bass-man re-conversion when I meet up with him in Oct.

Then again, if he's shouting the beers ( so long as it's not that wombat's piss they call Fosters )....I just might keep my trap shut!

[DJPhatman]

...when I meet up with him in Oct.

Harley, are you coming to the state of Michigan???

[DJPhatman]

Thanks for the thumbs up for both the jig and my english (I'm not a native speaker )

Additional recommendations:
Use thin plywood for the jig's base if you intend to "go deep" (like cutting baffle holes in 3/4" ply or more). You need quite a long router bit if the jig is 1/2" and the baffle is like 3/4". My version cuts through 1/2" ply with a regular router bit, 3/4" would be somewhere between tricky and impossible. The adventurous might let the router bit extend a little more, I find this far too dangerous with bits rotating at anywhere between 10.000 and 30.000rpm in a $35 router and therefore strongly advise against any experiments in that direction.

Most routers allow to remove their plastic base, which might give those few extra mm's needed to cut through.


Harley, since you are the unofficial "master of jigs" on this forum, please do not hesitate to share any improvements you make.

A tip for cutting circles with any jig (I use a Jasper jig myself) is cut half the depth from one side, then flip the work over and finish from the other side. Deep depth cuts with a 1/4" shank router bit and even a 1/2" shank can wander when extended deep into the work. I find that 1/4" to 3/8" deep cuts into the wood don't overextend the tool. FWIW.

[Harley]

Harley, are you coming to the state of Michigan???

Indeed!! pm me your address and phone no and we'll see if we can't come along and say hello and have a beer or thirty three.

[haydar]

sorry for dummy question, other than a circular saw, what I need the most: router, or jigsaw, or both for BFD projects? Bill mentioned jigsaw in the plan.
I'm really green in woodworking.

[LelandCrooks]

Router. With a handsaw or two, and a little creativity with a circular saw you can do anything a jig saw will do. Routers do so many things that that take forever or are next to impossible by hand.

[Bill Fitzmaurice]

A tip for cutting circles with any jig (I use a Jasper jig myself) is cut half the depth from one side, then flip the work over and finish from the other side. Deep depth cuts with a 1/4" shank router bit and even a 1/2" shank can wander when extended deep into the work. I find that 1/4" to 3/8" deep cuts into the wood don't overextend the tool. FWIW.

A 1/4" upcut spiral bit goes through 1/2" plywood like a hot knife through soft butter. I have one in a 1 1/2HP router that I only use for holes and radius cuts, it never bogs down.

[Harley]

A 1/4" upcut spiral bit goes through 1/2" plywood like a hot knife through soft butter. I have one in a 1 1/2HP router that I only use for holes and radius cuts, it never bogs down.

Is that the Rotozip or is it a plunge router with the rotozip bit?