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Hey guys so I present to you a challenge that I have now encountered twice and is rather annoying. Though fixable it seems to be a process that takes way to long to reach the desired effect.

I am trying to cut rosette rings of wood. Each time I cut the outside of the circle things go well. However when i cut the inside out of the ring I can never get the circle to be symmetrical. It is always about 10 thou off on one side compared to the other which will present gaps and is a visually noticeable amount of a-symmetry.

Are there any simple ways to cut rings of wood? Or at least something I am missing to ensure this doesn't happen?

Thanks for the help

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What method are you using right now?

.01 out of symmetry is a lot for a 4" diameter part or less. I assume you are using a router or dremel on a pinned pivot. The issue you mentioned can have two basic causes the first and foremost is that the base system you are using has some play in it either in the adjustment or in the pivot bushing/pin arrangement.

It is critical to have a near but not quite press fit between the pivot bushing and the pin so that the base can mot get out of symmetry while rotating on the base. Also the pin must be near interference fit in the work board holding the pin so that the pin can not wiggle at all. Also you want to make sure the pin is true plumb to the work board. If the pin tilts at all It will cause asymmetry.

The simple way to get around this is to use a 2 bladed fly cutter on a drill press rather than a router base on a pivot pin.

Try using some two-sided tape to hold the rosette blank in place while you are cutting, what may be happening is that the already cut ring shifts a bit as you are cutting the inner circle....been there done that

Greg

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Gwaltney Guitars

What I've found is that the grain can sometimes drag the cutter (or the wood) out of whack, if it's a solid bit of wood that you're cutting from, it's a grain direction thing.

Try cutting the inside a bit smaller (outside a bit bigger), just to remove the bulk of the wood, then adjust your router so that you creep up on the diameter you're after and only take a little off on the second pass. The second pass with the router adjusted usually takes care of the asymmetry. But as has been mentioned you need to be holding it down with some good quality carpet tape, so that it's still stuck down good for your second pass.

Anyways, worked for me when the same thing happened.

This is not uncommon . Todd suggests tape , you can also glue it to kraft paper, my favorite as that is then the bottom of the rosette . What I also like to do is this , when I do a wooden rosette , I will first make the rosette , then the hole . Then I can test fit the rosette to the hole and if need be sand the area that is tightest and get it in puckered tight . If I am ringing the rosette , ( my favorite ) I don't care about the fit so much as I will glue in the rosette then I use .020 blk or a bk/w/bk that is .090 and I can cut that channel last after the rosette is in, This give you a very clean line and takes out the variance of the wooden rosette . I may make a vid of this .

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