Workers Of Wood

Bushwhacker wrote: ↑Fri Oct 27, 2023 9:50 am My daughter bought a set of 2 end tables and a coffee table. They were used but very nice, made of heavy oak. Problem was, they had glass inserts for the tops. and she has 3 boys.
I opened my big mouth and told her that if she bought them, I would make her wooden tops for them.
The glass set into the tops on a 1/2 inch shelf. So I needed some thing that would drop into that space and still be strong enough to span the open space.
This is what i came up with.
I'll try to post the pictures in the order of the build.
No promises.
First, I cut a circle of 1/4 inch plywood to span the open space.
Then I made a 1.5-inch octagon.
I then made pieces to fit the center by cutting them at 22.5 degrees with the small end to fit the inside octagon.

Cherryville Chuck wrote: ↑Fri Oct 27, 2023 11:48 am Nice job David. I made a circle cutter quite a while ago (meaning there are no pictures) for my band saw. It's easy enough to do by using some ply and one of those adjustable outfeed rollers to support it. You add a cleat on the underside to fit in the saws miter slot. You need a pin (point of a screw or nail) in the ply to spin your circle on that's the distance from the blade you want the radius of the circle to be and you need to add a stop underneath that will hit the table when the pin is perpendicular to the edge of the band when you slide the table into position. Trim the corners of your glue up off with a jig saw before you start and they are usually the best starting point to start cutting on the bandsaw then.

So to use the jig you drop your would be circle onto the pin, start the saw, push the jig and piece into the band until the stop hits the table and then rotate the piece on the pin and cut the circle. You can build the jig in half an hour but you are cutting perfect circles this way so you might gain that time back in reduced finishing.

That's the simple version by the way. More time and you can make one with a sliding pivot pin that cuts a range of diameters if it's something that you might use a lot.

Herb Stoops wrote: ↑Fri Oct 27, 2023 12:56 pm fantastic job. You put a lot of thought and wrk into that, 3 tops,WOW.
It came out really nice too. good job on the finishing. That is a little different oak than I have seen before. I know there are different kinds,Red, White, and some more I am not familiar with.
Herb

Bushwhacker wrote: ↑Fri Oct 27, 2023 12:16 pm
I would love to see a diagram of that. I don't do a lot of circles but Like Rainman, "When I do" it would be handy and time saving.

Bushwhacker

honesttjohn wrote: ↑Sun Oct 29, 2023 11:30 am David - - you need a CNC with your newfound interest!!! Great job doing it the "old fashion" way. Lol

Cherryville Chuck wrote: ↑Wed Nov 01, 2023 10:13 pm Sorry for the delay David. Wifey has had me busy for a couple of days. There really isn't much to the simple circle cutting jig for a bandsaw. You need a piece of some kind of panel board that is large enough to hold your blank so that it's stable as you turn it. Most of it is going to hang over the end of the saw table so you need to support it. I'm using an adjustable outfeed roller. Level it with the table.

The photo shows an imaginary point where the pivot pin would go. You can use a nail, the point of a screw, or even install a dowel that will fit into a drilled hole in the bottom of your circle blank. Whatever it is just has to hold your blank as you turn it without the blank slipping off it.

You have to add a strip on the bottom of your jig that fits in the saws miter slot. You can attach the strip so that the end of the jig is close to band or even past the band so that you have to saw into it on the first pass. Doing that would give you basically the equivalent of a zero clearance insert which would help prevent slivering, so not a bad idea to do and if you cut the slot before you install the pivot pin it will make locating the pin for the desired radius easier.

The reason for the miter slot is that you have to slide the blank into the band. How far depends on how much wood you are going to cut off.

You'll notice that I have a layout line going to the band. Move the jig until that line is even with the teeth on the band and install some type of stop, either to the jig or the table that prevents the jig from going any farther that where that line lines up with the teeth. That is your optimal cutting position that will give the smoothest cut.

If you pre trim your blank to size you don't want to cut too close to the finished size when using a bandsaw. Cutting too close can put uneven pressure on the band and cause it to deflect. You'll have more pressure on the circle side of the cut than the offcut side. Leave at least a 1/4", more wouldn't hurt.

To use the jig, back it away from the band, put the blank on the pivot pin, then push the blank into the blade until the jig hits the stop. Then rotate the blank into the teeth.

I had made a fancier one but I can't find it and I haven't used it in a long time. It had a slot on the top of the jig, running 90 degrees to the band. I had the pivot pin on a strip that fit into the slot and could be locked down at any distance from the band to cut any radius I wanted (within the limitations of the jig). That jig takes longer to build but if you are cutting lots of circles of different radii it's worth building.

NOTE: the photo will orient correctly when you click on it.

Bushwhacker wrote: ↑Fri Nov 03, 2023 10:02 am

Cherryville Chuck wrote: ↑Fri Nov 03, 2023 1:58 pm

Bushwhacker wrote: ↑Fri Nov 03, 2023 10:02 am

Soooo ? Does this still require that I make a hole in my work piece?
When I made those table tops for my daughter, I had the glass inserts and simply centered them on the new table top after sanding, then drew my circle, the small ones I did on the band saw, but the large one I did with my jig saw.
Honest john has offered to send me a CNC machine in exchange for a Cheque. I don't know of any Cheques around here. I wonder if a couple of Canadians would do.
Sounds like a good deal.
I thought that you guys have that funny looking well dressed little guy , maybe you could send him to John. and we have this stumbling old fellow that no one would miss.
I'll have to see what John thinks.

Thanks for all your help Chuck.
Stay warm.

David

Cherryville Chuck wrote: ↑Sat Nov 04, 2023 12:26 pm A cousin who was a machinist told me one of the basic rules of machining. If the piece is small, take it to a machine to work on (e.g. router table). If it's large, take the machine to it (hand held router). I find that useful to keep in mind because if you're trying to figure out how you're going to do some job it tends to point you in the direction you need to go.