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Hi all,
I am looking for plans to build a router circle jig. It was featured in Shopnotes Magazine, volume 14 issue 83, which is unavailable at this time. I am trying to avoid buying four volumes to get the one plan. I have tried Amazon and Ebay to no avail.
Shopnotes site does have a video demonstrating it's use, but not the plans. It is for 1/2" to 4" holes but am hoping to modify it to fit a 5" mirror. Any help would be appreciated.

Thanks,
Bob
 

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Welcome to the forum, Bob.

Search the forum for circle jigs. There are many posts from members who have made their own.
 

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Theo
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Hole saw is an option, I have a set that goes up to seven inches.
 

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If it is not there all the plans are on the Shopnotes DVD.
I bought that ShopNotes DVD recently. I have a lot of reading to do. :)
Since I didn't have any of the issues, it was a good buy for me.
 

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There is a much simpler way to make small circles.

Make a circle into which your router base will fit. Determine the diameter of your router base and the diameter of your bit. Be sure that your bit is centered.

If the hole is the same size as the router base the cutout will be the diameter of the bit, obvious. If the hole is 1/2 inch larger than the base, then the cutout will be 1 inch larger than the bit.

To cut a disc, the hole must be diameter of the hole can be figured this way. The radius of the base + the radius of the bit + the radius of the desired disk = the radius of the cutout.

So, with a router base that is 5 inches in diameter its radius is 2 1/2 inches
Diameter of the bit is 1/4, its radius is 1/8
Desired disk diameter is 13 3/4 inches, radius is 6 7/8 inches.

2 1/2 + 1/8 +6 7/8 = 9 1/2

For a 4 inch disk: 2 1/2 + 1/8 + 2 = 4 5/8

Since the size of the base does not change, if you use the same size bit you just write down the information, 2 5/8 in this case, and add the radius of the disk that you want to get the size of the cutout.

I hope that you find this method for making cut outs and disk useful.

Browne
 

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Browne, if the bit and the sub base plate are both centered this method will work. Very few router sub base plates are centered from the factory.
 

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Mike,

Perhaps I should have been clearer when I said 'be sure that the bit is centered' and said to center the base plate on the router and the bit to the base plate?
 
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