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I've been using a popsicle stick with an exacto blade to cut my rosettes so far, and I'm ready to step up to a more precise instrument. Veritas and Lie Nielsen both offer radius cutters. Does anyone have any experience with either one?

Veritas: http://www.leevalley.com/us/wood/page.a ... 3314,69873

Lie Nielsen: http://www.lie-nielsen.com/tools-for-in ... us-cutter/

I,ve got the the L/N one good for defining inside and ouside of your rosette.I got the extended rod as well. They make a V groove . practice on scrap WRC an spruce/I/ would also get the miniature router from L/N which I have . You can start your cuts with #3 gouge in the circle and get fairly level with the L/N miniature router which IMHO is extremely accurate and can be used for other jobs. PS I also use the die grinder from john hall and the new router circle hole cutter from stew- mac . I had a machinest center the plastic from stew -mac and use the die grinder with it vy slick. I also have homemade rtr circle cutters using a ryobi lam trimmer and baltic birch ply . many ways to go.

Popsicle stick is a great method. The real advantage is that the blade is fixed, ideal for doing rosettes that are of the exact same dimensions.
I have many of them, 'set' to various diameters.

Thanks guys. Yeah, I have a mini router plane from Veritas that excavates the rosette well, and a smaller blade for routing the bridge. Ernie, would you say the radius cutter is worth the money? Is it a major improvement over the popsicle stick aside from being adjustable?

I can/t comment abt the popsicle stick as I/ve never made one . You might try one like michael, to see if it works for you. There are other homemade circle cutters around, I think I saw one in the courtnall an stanley doubtfire books.Or google plans for a circle cutter or youtube video.Luthiers sometimes make their own.

The groove cutter blade on the LN looks interesting. One thing I don’t like about some circle cutter tools is the small pivot pin which for the one I had was difficult to secure properly without a tendency to enlarge the hole in the soft soundboard wood resulting in occasional sloppy or inaccurate cuts.

Here’s a homemade version that has a very stout blade and pin and gives very accurate cuts.



I’ll add a post in the tutorials section for anyone interested in how it’s made.

Joe

It's there now.

Your question seems to suggest that the Popsicle method isn't working for you. What exactly is the deficiency/problem?

I have a tutorial in the old tut file on making a circle cutter. I still use it on some guitars, vs the trim router version, which I also have. I, most always, do the Spruce rosette channels by hand, but use the router on Redwood and Cedar.
viewtopic.php?f=10102&t=13581%22

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Are there advantages to using a hand circle cutter vs a trim router or Dremel? Less 'furring' of wood fibres?

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Now theres a real nice sweetie no brainer pie circle cutter.

Thanks for posting it.





For those of you whos gotts money to burn...there always Lenard and Thomas, both make really nice toys eh.

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"Are there advantages to using a hand circle cutter vs a trim router or Dremel? Less 'furring' of wood fibres?"

A sharp blade will give a better defined edge than the typical less than perfectly sharp carbide router bit, but good and bad results can be had with either.
I use a cheap double bladed flycutter chucked into a drill press to cut both the inside and outside radius at the same time. Still need the trimmer to take out the wood in between.

I do like Joe's homemade cutter - very nice!

That's beautiful Joe. Thanks for posting it. And that's a good point about the small pivot pin in softwoods.

Michael: My issue with the popsicle stick method is that the blade is not terribly secure, chips easily, can move laterally and is not very comfortable to use (having to push down on the exacto blade as I'm turning it). It's worked sufficiently for the guitars I've made so far, but I think I'd like something stouter going forward.

You shouldn't have to push down as you are turning it. Maybe a light tap after you've done a full revolution so that it sinks a bit further. I don't use an exacto but a very pointy scalpel blade - inserted so it isn't completely upright. A dab of CA on the upper surface (around the blade entry) prevents it from being too loose. Never had a problem with the method myself and it always cuts very clean, precise lines.

Good to know. Maybe I'll give the CA glue a shot.

Now if I can just figure out how to keep the popsicle from dripping on the soundboard...

Joe , is that circle cutter made from cocobollo? vy nice job.

Thanks for the compliments on the homemade circle cutter. It's simple design was taken from the Buchanan style cutter modified slightly with elements from a couple others I like.

Ernie, it's made from Goncalo Alves. It's not real heavy, weighing about 95g without the brass pin.

Joe

Any time I use to try exacto blades I have switched to scalpel blades they are very sharp. I use Blade Rib Back Surgeon Bard-Parker PT# 25 Carbon Steel. http://www.amazon.com/gp/product/B005780YPQ. They fit in a #6 handle.

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On my current build I used this contraption with some success:



Once the perimeter was scored, I then went in with the dremel (or broken scalpel for the small channels) to clear out the middle. It was a pain to have to change single bevel blades (bevel on outside or inside) and because I only have one circle cutting jig I had to disassemble to plug in the dremel. I also experienced issues if I ignored the grain direction & direction of cut (laziness). But if sharp, I can't see me deviating much from this method. The tools will no doubt adapt and multiply over time, as is their want.

Here's the result:

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Some really good suggestions/cutters in this thread. Thanks guys. And Todd, looks like you identified another problem I have.

Has anyone here tried using a circle cutter hand tool like the ones you can find at local hardware stores? They're inexpensive and are adjustable to different diameters. They're technically made to cut holes in dry wall, but I'm wondering if it would work. Might try on some scrap this weekend.


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Weird I've never seen this. Then again, I don't really look through the StewMac catalog as much as I used to.

I think I could use this to rig up a fix on a rosette that I sanded away some purflings on, they apparently didn't get down into the slot enough.

Thanx!

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By the way, the hand make tool is absolutely beautiful. Sadly, I am not at a point where I'm comfortable making my own tools yet.

Again, beautiful work.

I own the LMI circle/rosette cutter and it is the only one i have used, well made and does its job. Its downfall for me is you can't see it doing its work and you can't see the work itself, you are pretty much working blind. For something as fine and noticeable as a soundhole IMHO any tool which gives me a better look at whats going on would be preferable. The pop stick, both LN and LV tools, perspex/lexan and many assorted home/shop improvements are way better suited to our needs as you can see the cutter at work.

Steve

Oops double post perhaps a mod can remove please.

Thanks Steve