Source for small adjustable circle cutter?

[Larry Edgerton]

I looked around and could not find one small enough, but.....

I have this set, and they do a very nice job, clean cuts. You could buy the 5/8, cut the wheel but not all the way through the stock, change to a 3/16" bit and drill the axle hole.

http://www.leevalley.com/us/wood/pag...at=1,180,42288

Just another random thought..........

[Ben Rivel]

Thanks for the suggestions. I'm sure there is a micro circle cutter out there somewhere, but I can't find it.

These "Mechanical Marvels" models have considerable precision (I've built 8 so far, the most slop I've got so far is about 0.006-7", or a bit less than 1/128"). Store bought dowels (even the "precision" ones I've found) aren't even close to their advertised size, most are undersized 0.010 or more. I don't have a lathe (yet!) but have resorted several times to visiting a friend with one to make fairly precise dowels. I think I would need to bore the hole first, I am not sure I could precisely center a hole on a disk that was already slabbed off. Wood choice is important too, since I live in a pretty humid area (massive understatement there).

Thanks again.

Wow, thats quite a bit of precision to expect from wood.

Are you getting the plans for such devices from somewhere or are you figuring them out from images/video?

[Richard Hash]

Ben,
I'm going thru the early 1990's Raymond Levy book "Making Mechanical Marvels in Wood", trying to keep things as tight as possible and still function smoothly. It's the first woodworking I've ever done where I've needed to use a micrometer (I found out I go cross-eyed really fast trying to even see a 1/128" now), and I've learned alot about what species work well for me and how grain affects expansion. I live near the Gulf coast, and my shop can be 98% humidity in the summer, so planning for shrinkage is important. What I've noticed is that mesquite and jatoba barely move for me at all when I take them inside (where humidity is maybe 50-60%). The few samples I've watched have moved about 0.002 which I think is just amazing! So I tend to make the tight tolerances pieces out of those...

[Edwin Santos]

If you have a plunge router and guide bushing set, here's an approach that might work for you:

Make a 1"hole in 1/4" or 1/2" material using a Forstner bit or a hole saw, or a circle cutter on a drill press. This will be your template.
Secure this template to your stock with hot melt glue or double face tape, and then use a plunge router with a 1/2" template guide bushing and a 1/4" router bit. The resulting circle you will be cutting out should be precisely 5/8" in diameter and not require any sanding or clean up.
You could drill your 3/16" hole by marking the center of the workpiece while the template is in place, using the same 1" Forstner bit you used to make the template (the center spur of the bit will mark the center of the wheel. Basically you're using the drill bit like a transfer punch. Once the center is marked, drill your 3/16" hole either before or after you rout the wheel. Since precision is critical to what you are doing, I think you should drill the center hole with a drill press to keep it square to the wheel so maybe it makes sense to do so after the routing operation.

Make sure your router bit is centered in the bushing.

You can accomplish the 5/8" diameter wheel with other combinations of template hole diameter, bushing diameter and router bit diameter. For example, you should get the same outcome with a 1 3/8" template hole, a 1" guide bushing and a 1/2" router bit. I hope this makes sense. As I read what I'm writing here, it sounds more complicated than it really is. You don't have many of these to make based on the picture, so this should only take 30 minutes or so.

[Dan Cameron]

Here is a way to make your wheels. Cut squares about 3/4" across and drill a 3/16" hole in the approximate center. Buy a 3/6" partially threaded bolt and cut off the head. With washers/spacers push the bolt thru the wood square and with a nut, mount the bolt in your drill press chuck so that the wood spins with the chuck. Now make a right angle mount for a router that you clamp to the drill press table. Position a straight router bit below the wood square with the bottom of the bit 5/16" (the RADIUS of the desired wheel) away from the rotational center of the drill press. Turn on router and drill press and SLOWLY feed the quill until the all of the square is turned to round. Voila!

[Edwin Santos]

Store bought dowels (even the "precision" ones I've found) aren't even close to their advertised size, most are undersized 0.010 or more.

Thanks again.

You could try the inexpensive hardwood dowels sold by the Beall Tool Company for use in their wood threader fixture. They claim to be accurately sized and they offer 5/8".

[Jason Mikits]

If you use the lathe, I would not predrill the center hole if you need it to be precisely concentric. I would chuck the piece of wood, use the tail stock while getting the outside diameter, and then use a drill bit in the tail stock (morse taper drill or morse taper chuck and drill) for your center hole. Otherwise your center hole will likely end up slightly off center, or not quite square.

[Dave Sabo]

Can't you just order 5/8" wooden discs fro pm a website somewhere ?

[Kerry Wright]

Do a search for a 5/8 plug cutter. Grizzly even has a set of various sizes.

[lowell holmes]

Check this add.

https://www.infinitytools.com/tenon-...24PhoCYOLw_wcB

[johnny means]

Wow, I thought plug cutter wasn't going to come up.

[Greg Parrish]

For small stuff like this why not buy a set of plug cutters. Will prob be cleaner than hole saws.

EDIT - DOH! Should have looked at page two before responding. LOL

[Edwin Santos]

If you have a neander streak in you (and because you don't have many of these to make) you could also consider cutting a 5/8 x5/8 blank and pounding it through a dowel plate, then slice off the discs you need. The largest size in the Lie Nielsen dowel plate happens to be 5/8", or if you have a 5/8" drill bit you could drill your own through a piece of metal. Paul Sellers demonstrates a "poor man's" dowel plate using hardware store washers with the appropriate I.D.

[Charles Lent]

There are more reasonably priced 5/8" plug cutters if you decide to try them.

https://www.amazon.com/Carbon-Steel-...F8+plug+cutter

https://www.amazon.com/dp/B01IHNP27M...8FJVG650&psc=1

Charley

[lowell holmes]

Or this add.

https://www.amazon.com/s/?ie=UTF8&ke...l_8inyyfkeuw_b

There are several cutters.