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Does anyone know where I could have an archtop billet CNC routed. I have only built flat tops and would like to build an archtop without having to hand carve the top and back?

There are a few of us CNC guys on the board. It may be hard to find a volunteer willing to design and cut just one of something like this as it does take some time to develop a good model for a carved part.

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http://www.PeakeGuitars.com

Hi Steve,
I am not aware of anyone who makes them as a "standard" product.
I have seen them on ebay.
If I was you ,I would just try one from scratch-it's not as hard as you might think-Use Bob Bennedetto's book for a reference.
I have a tutorial I am going to do on carving plates,so keep an eye out for it.
Brad

I agree with Parser and Brad. Though if you are dead set on purchasing a carved set of plates you will still need to do a lot of hand graduation of the plates.

John Watkins I believe has the CAD/CAM files for carving plates you might try him at http://www.cncguitars.com

Another way to go is to purchase laminated plates that are pressed into shape. I think Ken MacKay who drops by here sells them. You might also wish to try Acme Archtops http://www.acme-archtops.com

Lastly, carving plates isn't all that difficult as Brad points out. Follow the Benedetto book and I suspect Brad will be posting a great tutorial and you'll be well on your way.

If there was enough interest in them then I could run some off. I think a lot of people are using laminated plates now, so I'm not sure if there's enough of a market for solid wood plates to offset the setup costs. A CNC carved plate is definitely a high-dollar item compared to the laminated plates.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

All you are going to get if you can find it is roughed out and ready for the real work of fine carving and tuning. The rough out is easy.

Do you want to build an archtop? Carving the plates is the nub of it.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I agree with Howard, the rough carving isn't all that difficult, it's learning how to correctly hand graduate a plate that is. The rough carved CNC plates I've seen are done to a hair over 1/4" thickness to accomodate graduating and final sanding.

Bob, I didn’t realize that a lot of people are now using laminated plates. Are you referring to manufacturers?

Do you have a Rhino CAD program for a standard Benedetto style plate or were you thinking of doing the programming yourself if interest warranted?

Luthiers Automation sells a Rhino CAD program for Archtop plates for $550. http://www.luthiersautomation.com/guitars.htm It is slightly different in dimension than the standard Benedetto shape many of us use.

Bob, assuming you already had a good Rhino file, is it out of line to ask what you would charge to carve per plate?

Contact Greg German of http://www.germanguitars.com I know he has a CNC machine and he builds archtops. He actually cuts all his plates on his CNC, and then does the final tuning by hand. I'm sure he would be willing to do one for you if the price is right.

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Tracy
http://www.luthiersuppliers.com

I'd program it here, I only use outside CAD if a customer sends it for a machining quote or if someone's paying me to fix it. It's not very hard to draw up a model from decent plans, especially considering some of the hand-carved monstrosities I've put into CAD for customers (think PRS-style body contours and kick up the complexity a couple notches). I'm in the wrong business after seeing the LA site. Time to start selling CAD models!

On the cost of machining it has a lot to do with the part finish and quantity. I can make roughed out plates pretty quickly, or I can make plates that only need to be sanded with 400 grit, but will of course cost more. Quantity's also a big deal if it's an item that I don't have set up yet. If there's a decent initial quantity then I soak dev cost, if there isn't then the dev cost adds a lot.

It's a funny business to be in as I have some sort of confidentiality agreement with many of my customers, and certainly with all my biggest and most prominent ones. Because of that, I can't show most of the best work I've done. But, generally, I'll handle any project if there's enough interest to offset the setup costs.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

You mean there are famous builders who don't want it known that they farm a bunch of the work out? I'm shocked, shocked.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I have the Benenetto book and the rough carving doesn't look that hard. I don't have as much time as I would like so I try to save some if I can. Has anyone built one with red spruce? What I really hope that I would find was someone the a CNC of even a low tech copy router who would rough cut my billet for around $100.

Steve Brown

Thanks for all the answers and suggestions!

Steve if you are trying to save time, an archtop may not be the way to go with a build. They take considerably longer than flattops for example.

Red spruce billets for a 2-piece top 17-inch Archtop for example will cost you a pretty penny and won't be the easiest to find. Sitka spruce makes a terrific archtop and is probably the most commonly used top.

Let me know if you find someone to do that for that price...that's pretty cheap!

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http://www.PeakeGuitars.com

There are guys around with retirement funds and ShopBots that'll do some of this stuff pretty cheaply, but you get what you pay for.

I think you could rough out a plate pretty quickly with an angle grinder or a lancelot. The main benefit of CNC in the case of archtop plates would be that you can have the outside surface in finish-ready condition when you start, so you'll only have to deal with graduating the inside (since the outside profile, to my understanding, is constant and only the inside carve changes for most archtop guys)

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

The outside comes first, but then the outside recurve is revisited when tuning after the box has been closed up.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I've only built about a dozen archtops so I'm not an expert on them by any means, but I have to agree with Howard
that they take considerably more time to build than a flat top guitar. My results are good on every archtop that I've built
and there was marked improvement on each one from the previous one.

There's no possible way that you are goin to get a top carved via CNC that is finish ready since the recurve must be
cut by hand after the body is closed and ready for tuning. Sure, a goo CNC guy can give you a surface that is ready for
your final sanding and finish, but they can't give you the dimension that need to be arrived at through fine tuning the
carve and listening to it as you do.

An archtop is not a great choice for a build of time is at a premium for you....especially when it's your first archtop.

Regards,
Kevin Gallagher/Omega Guitars

Thanks for all the advise and suggestions. A few notes: Old Standard Wood has Adirondack billets for about $85 - obviously not cosmetically first grade.
I have an offer to carve a joined and thicknessed plate provided by me for $150 in an existing 17" standard pattern.

Again - Many Thanks
Stephen Brown