4" disk

I have that trouble too, the blade’s cutting edge has to be aligned with the center pivot point of the jig,
I could never get consistent circles so I scrapped it and use my router with a home made circle jig, perfect circles with no saw marks, hope this helps.

-- MARK IN BOB, So. CAL

Move the jig so the leading edge of the teeth are on a line with your pivot pin. That should solve the binding problem. Somewhere I saw a chart that had a 1/4’ blade should be able to cut a 3/8” radius- that was probably the absolute smallest.

A wondering blade might mean that the tension on the band saw blade is not sufficient.

-- Lew- Time traveler. Purveyor of the world's finest custom rolling pins!

I am planning on using a 4”hole saw when I start building my drumm sander. The 1/4” pilot drill will aid in drilling the larger center hole also.

-- Carpenter assembles with hands, Designer builds with brains, Artist creates with heart!

I agree with papadan, except to get a 4” disc, you need a larger hole saw. The 4” is the outside diameter of the hole saw, which will be the size of the hole you cut. To get a 4” disc, you will need a 4 1/8” or maybe 4 1/4” hole saw.

-- She thought I hung the moon--now she just thinks I did it wrong

Got lathe?

-- Manufacturer of fine quality sawdust since 1984. Comments and advice on my shop welcome. Check it out at http://lumberjocks.com/dbhost/workshop. Gladly accepting shop build donations!

im with mski…the holesaw does work but if you dont have that big of a hole saw jig up your router to cut a radius around into a full circle…makes perfect edges with no bumps to worry about or sanding to do.

-- My purpose in life: Making sawdust

Try a circle cutter with the blade turned to pruduce a flat circle instead of a wheel profile. I used this to make a laminated drum as part of a toy train many years ago. Use a drll press and slow the speed to about 250 rpm.

Draw the 4” disk with a compass. Using a jigsaw, cut close to the line – don’t worry if it isn’t very even. Drill a 1/4” hole in the center of the circle – use the hole made with the compass as a pilot. Insert a 1/4” bolt, with washers, and tighten down with a nut. Insert bolt end in your drill or drill press. Hold a sanding block to the edge until you have a 4” diameter circle.

JimC

-- A veteran is someone who, at one point in his/her life, wrote a blank check made payable to "The United States of America," for an amount of "up to and including his/her life".

you all have good ideas thank you…

I thought of the hole saw and circle cutter and this would do the job well. but ass i thought about next step i realized i know have a 1/4 hole in the center and i need it to be a 5/8 hole. there is only one kind of bit that i know of that will chase that hole. I do not have this bit and on pricing this out it was going to cost 20 to 30 bucks.

The lathe is and idea that i will try next. i was thinking of gluing 8” up at a time.

Jim , this system work but you have to be care full you do not oval the peace. 21 would take some time but it could be done.

-- I get out in the shop when I can

The lathe is a good idea, but it could be a little difficult getting a consistent diameter unless you are very careful and check your progress often.

-- Mike, American in Norway

You can still rebore your hole in your 4” circles after leaving a 1/4” hole behind. Just glue a dowel in the hole, cut off flush and redore with a 5/8” spade bit. you only need enough to get the bit centered and started.

-- Methods are many,Principles are few.Methods change often,Principles never do.

If you can get them cut close to the line; after assembly put a sandpaper covered piece of plywood on your sander bed and lower the turning discs (drum) to it. Sanding them all at the same time. They will be exactly the same diameter.

-- Father of two sons. Both Eagle Scouts.