Cutting small discs

[wizer]

I have some 20mm thick walnut that I want to cut out some roughly 80-90mm dia round discs.

I'm wondering the best way to do it. Should I use a hold saw like this (I can live with the pilot hole)? Will this end up with too rougher finish?

The only other way I thought is to use the triton router's circle cutting jig. Not sure if it will cut that small?

Comments greatly recieved

 

[JFC]

Why not use the holesaw to make a jig and then use your router with a guide bush or top bearing , you could countersink the hole the holesaw makes and use this to screw the template to your walnut .

 

[GCR]

Have you considered a "tank cutter". Basically a rotating cutter (preferably driven by a pillar drill) which rotates about a drill/pilot (just like the cutter you highlight). The cutter is adjustable for radius and the cutting edge can be ground to give a good edge with minimum tear-out. The trick is, like the screwfix tool, to drill halfway from both sides. The downside is that they can be a bit daunting as all the bits spin round!

Bob

 

[DaveL]

WiZeR,

I cut discs from walnut form the motor bike toy I made last year. I ended up with a jig to sand to the finished diameter using my belt sander.

I tried to cut them with a jig on the router, you have to be very careful, stick the job down with double sided tape to stop it moving about. I then had problems with tear out, the grain in effect chances direction as you go round the disc.
I also have a tank type circle cutter, you need a pillar drill and its needs a very slow speed as most of these are way out of balance, I taped a counter weight on but would have liked a suit of armour while using it. The finish was still not that good.

 

[beejay]

I use one of those multi blade hole saws for cutting discs and although cheap, the finish isnt too bad,,just needs a light sand normally. I havent cut walnut but lots of mahogany and they are OK.
I wish youd try the Triton though and ket us know how it faired.
beejay
http://community.webshots.com/user/eunos9

 

[wizer]

Thanks guys. I don't have access to a pillar dril so might have to see how I get on with the triton. If not then i'll experiment with holesaws

 

[Garrett in Victoria BC CA]

Do you have access to a lathe? Just turn the dowel to size and slice the disk of the end using a bandswa.

If you do it this way, make a vee block to hold the dowel for the bandsaw.

Cheers, Garrett

 

[Barry Burgess]

Thanks guys. I don't have access to a pillar dril so might have to see how I get on with the triton. If not then i'll experiment with holesaws

I use Link
This is an adjustable hole cutter that I use for diameters less than 200mm.
Be careful cutting a small dics with the Triton circle cutter and use the smallest bit you have.

Mod edit to reduce URL length

 

[Gill]

Here's the underside of a circle cutting jig I made for my old Bosch 400 router out of MDF:

I've been able to rout out discs with a diameter of less than 20 mm using this. It didn't take long to make.

Gill

 

[JFC]

Another way and alot safer would be to drill a hole in a scrap bit of say mdf and use a guide bush and straight cutter , work out the size of walnut disk you want and over cut the hole the size of the guide bush and cutter . You can then clamp this jig to your work and route down to the last 00.3mm ish and simply cut out the rest with a stanley knife and clean with a quick sand .

 

[devonwoody]

No practical experience of such an excercise myself but have you considered the possibility of 3 disks to make up the 20mm overall thickness. Then glue them together after disks cut. Even a contrasting centre colour might attract you to this idea.
Using the router with a template and not to deep a cut to make, could work, and double sided tape has not got such a load to carry if thin pieces?

 

[SketchUp Guru]

It's probably too late now, but here's another option for you. You could cut a number of squares with a hole drilled in the center, stack them up on a piece of threaded rod with a scrap piece on either end. Lop off the corners on the tablesaw or with a hand plane. Chuck it into the lathe, turn the stack to the desired diameter and sand them smooth.

I think you could get a smoother surface on the end grain with a chisel than with a hole cutter of any type.

 

[radicalwood]

how about a circle cutting jig but for the band saw there are a few patterns for this on the web. you could also use the same jig on the sander.

All the best
Neil

 

[Taffy Turner]

It's probably too late now, but here's another option for you. You could cut a number of squares with a hole drilled in the center, stack them up on a piece of threaded rod with a scrap piece on either end. Lop off the corners on the tablesaw or with a hand plane. Chuck it into the lathe, turn the stack to the desired diameter and sand them smooth.

I think you could get a smoother surface on the end grain with a chisel than with a hole cutter of any type.

That is how I would have done it, but without cutting the corners off first.

Taffy