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Hi all, here's a carved top tutorial Setch posted at guitar.com awhile back. Apparently guitar.com lost the thread, and Setch hadn't backed it up, so we thought it was lost forever. I was cleaning out some old folders on my hard drive around Christmas and found that I had saved it. So sorry Setch for just getting around to it, but I told you I would and here it is. I cleaned it all up and rehosted the pictures for easier viewing. From here on out it's Setch speaking :D .

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This is the blank I glued up for the demo. It's about 6" across, not fullsize, and just screwed to some scrap 2x4 so I can grip it in the vice. Normally the top to be carved would be glued to the guitar body.

1.jpg

Next step is to route a rebate around the blank to the final depth of your carve.

You'll notice the top of the blank isn't flat anymore - I messed up here, and because I was rushing, got the steps out of order - so do as I say, not as I did :D Cutting this rebate is easy when the top is flat, and very tricky if you've already planed the neck angle.

2.jpg

Third step (not second!!!!) is to plane in the neck angle. The process for calculating this is a post all in itself, so I won't go into it here. Do this *after* routing the rebate - this makes life so much easier...

3.jpg

After the rebate is cut, and the neck angle planed, you plane a second angle into the top. This is a straight line from the end of the fingerboard, to just in front of the bridge poistion. I don't have a great shot of this, so You'll have to have this one again...

This is basically the state the top is in before you actually begin carving. The lines show where the neck angle ends, and where the secondary angle ends, just infront of the bridge.

4.jpg

In this pic I've marked out areas which must remain flat with pencil. These are the bridge location and the area where the fingerboard will be glued down.

Time to dig in with the spokeshave. I've cut a fairly constant bevel all around the body. It runs from just above the routed rebate, upto half way between the flat areas and the edges of the body.

5.jpg

In this shot I've started to introduce a second angle. The idea at this point is to maintain 2 facets, which will make it easier to keep the carve symetrical, whilst hogging away the bulk of material. I've not really strated to create the final shape at all, but it will be easier to make it even if I strat with a symetrical base.

It was at this point I started to experience real trouble with a big knot in the waist of the cutaway side. Instrument grade wood will be free from such knots, so they won't be a problem.

6.jpg

I think I missed a step here - in this pic I've removed the corners which defined my facets, so I've got a more or less even curve over the top. You can tweak this lots, regularly checking the shape with light from different directions, and looking at it in profile. It's all just adjusting the convex curve to your tastes.

Then, I dig out the swan/goose necked scraper. I use this to introduce a recurve arount the edge of the carve. This is a lousy picture, so I'll try to explain what's going on in the next post.

7.jpg

Ok - Explaination of the recurve. With the spokeshave you can only create a convex curve - like in diagram 1. I use the scraper to create a concave curve around the edge of the carve, so it ends up like diagram 2. Once this is done, you can use a combination of scraper and spokeshave to flow the two curves together, your aim being something like the curve in diagram 3. This was a bastard to photograph...

On some instruments this recurve actually ends up being more exagerated - so the carve actually goes below the height of the binding, them back up towards the bridge.

8.jpg

And here's a shot of the carve - on a real instrument there would be a bunch more sanding, but the bulk of the work is done. The knots in the pine made the waist of the cutaway side impossible, so it's still pretty rough.

9.jpg

....and here's the aftermath.... note broom!

10.jpg

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Thanks Devon. Setch, what if any consideration would you have to take when planeing the neck angle on a double cut guitar, say a PRS? Do you think the neck angle should carry into the horns? How would you attack a PRS top?

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Thanks Devon. Setch, what if any consideration would you have to take when planeing the neck angle on a double cut guitar, say a PRS? Do you think the neck angle should carry into the horns? How would you attack a PRS top?

On my double cutaway I wanted the fretboard to sit on the binding at the neck joint, so I calculated the neck angle to allow this, then planed that angle into the neck joint area. However, the angle couldn't continue along the horns, since it would have made them thinner than the body, and broken through the maple top into the mahogany body.

It's hard to describe how the carve flows to accomodate the neck angle, but the shape achieved is a lot like Ormsby's vine guitar - rebated all around the perimeter, with crests along the top of the horns and a shallow "valley" where the neck meets the body.

The other approach is to simply carve the body to a shape you like, and then have the neck sit in slightly proud of the body. I used to think this was 'cheating' somehow, but I've since seen it utilised very elegantly by a few folks, most notably David Myka, and I now think it's a perfectly valid solution, which also makes for a less involved top geometry.

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I have a few questions... I'm thinking of doing a double-cutaway mahoghany guitar with a carved maple top. Bolt on neck. I don't want the carve to be too severe, pretty much like a Les Paul. The way I was thinking I would do it would be to attach the maple top, cut out the body shape, do my pickup routing and drill the holes for the TOM bridge, and then make a sort of skid, and run a router over the body perpendicular to the glue-line. Then for the back of the guitar I would freehand sand it down to the right angle or whatever. Will this work? Do you forsee any problems I might have doing it this way? Are there any other ways to do it? This isn't the first guitar I've built, but the first carved top, and I'm not sure how to do it properly. Thanks for your help.

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28if i'm not completely sure what you mean, can you draw a picture for us explanation-impaired? :D Just remember, free hand is your worst tool :D

Edited by dawn8

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I used to use a bearing guided cove bit, but now I use this:

carve_with_jig.jpg

It's just a simple plywood base, which raises the router above the top. Instead of a bearing, it incorporates an adjustable plywood guide, which the guitar is run against, controlling how far towards the centre the cutter can reach.

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It's pure genius. I'm a-make me one of those. :D Well, something similar at least. My work surface isn't that big or nice.

Greg

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My work surface isn't that big or nice.

That's a piece of 24" x 36 x 3/4" plywood sitting on top of a workmate - hardly the Ritz Carlton of work surfaces :D

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So shiny! Well, it's at least a Super8 by comparison, but yeah, I can probably swing that. :D

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It used to be part of a shelving storage thingy at my old job - the shop got refurbished, and I nabbed a load of pre-finished plywood which would have been chucked out otherwise.

I just used some of it to make up a totally gratis myka-style neck pocket jig - 99.9% recyclyed material, apart from a handfull of machine screws and hardware. Dumpster diving rules :D

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I used to use a bearing guided cove bit, but now I use this:

carve_with_jig.jpg

It's just a simple plywood base, which raises the router above the top. Instead of a bearing, it incorporates an adjustable plywood guide, which the guitar is run against, controlling how far towards the centre the cutter can reach.

Is the adjustment of the plywood guide something like a series of (properly spaced) holes for a bolt & wingnut or something else more ingenious?

I am also wondering...Is the guide placed low on the body so that the outermost (deepest) cut is done first,

or is the shallowest innermost cut done first right across the whole area to be shaped followed by the deeper more peripheral cuts and the guide lowered with each router adjustment?

I hope this made sense... :D

RobSm

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The adjustment is currently an f-clamp which clamps the guide to the jig, and also clamps the jig to the wroktop!

The guide registers off the body approximately 3/4" from the worktop, and I cut from the centre outwards.

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The adjustment is currently an f-clamp which clamps the guide to the jig, and also clamps the jig to the wroktop!

The guide registers off the body approximately 3/4" from the worktop, and I cut from the centre outwards.

Thanks heaps!! :D

I already have pieces cut & lying about.....I just gotta get a wroktop... :D

RobSm

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I just gotta get a wroktop... :D

Saw one on ebay the other day...went real cheap too, I should have snapped it up.

Very cool idea, Setch.

My question: the top I'm adding to my guitar is only 10mm thick (that's a little less than half an inch for you imperial types). Is it worth trying to carve this?

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Half an inch is all that a les paul has. So you could carve all the way until JUST going through... or you can do like I'm doing for my next build. 1/2" curly claro top, and the carve carves INTO the back wood... so you get more carve per top thickness, and get that awesome two tone look I love from the front :D

Chris

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Half an inch is all that a les paul has. So you could carve all the way until JUST going through... or you can do like I'm doing for my next build. 1/2" curly claro top, and the carve carves INTO the back wood... so you get more carve per top thickness, and get that awesome two tone look I love from the front :D

Chris

I'm a little nervous about carving too much from the edge though --since it's essentially a hollowbody, I'm worried about making the top too thin around the sides, afraid the glue would fail or something.

How many millimeters do you suppose I should leave at the edge? I guess I'll measure my acoustic's top--if that's strong enough to stay on, then it should work for this guitar too. I can also play around with carving the innards too.

I thought Les Paul tops were more like an inch thick though?

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I'm a little nervous about carving too much from the edge though --since it's essentially a hollowbody, I'm worried about making the top too thin around the sides, afraid the glue would fail or something.

How many millimeters do you suppose I should leave at the edge? I guess I'll measure my acoustic's top--if that's strong enough to stay on, then it should work for this guitar too. I can also play around with carving the innards too.

I'd leave 1/4" (6mm?) at the edge - that's pretty standard.

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I have been experimenting, and have come to the conclusion that I can do a reasonable job.

What bit size and what router speed do you recommend for use with the jig?

TIA

RobSm

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Your top routing jig is a really neat idea, Setch, and I have a copy half built in the garage at the moment, but something's been bugging me. I want to replicate the top curves of a PRS Custom 24. Your jig can cut nice contours at equal distances from the edge of the body, but on a Cu24, you have to contend with different contours.

If you take a cross section through the length of the body, the curve at the back running along the length of its centre line falls over a 150mm distance from 48mm thick to around 35mm thick.

If you take a line across the width at the thinnest part, the waist between the pickups, then the same height loss occurs over a much steeper gradient, only about 5mm of travel from the bridge and pup plateau to the edge faux binding. I can't see how this jig can replicate the contours of a top that is not concentric, if you get my meaning.

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It could be tweaked to cut that kind of carve, but it's really mostly to provide a symetrical, rough cut, which hogs away material prior to final shaping.

I then dig out the 40 grit sanding discs and create the final shape, and it's at this point that I vary the contours and exact shape of the recurve area.

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Can you give us ,or pics of the jig or a drawing? Also, per a previous response, I thought LP tops started at 1". My friend who's built them for many years and a set of plans I have call for 1 inch. I suppose you can do what you like and make the contours a bit shallower.

Setch, I noticed on your blog you chambered your LP. Was that normally done? I know some custom ones were that way, but other than those, I thought LPs were solid.

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Not being an expert or anything, but you'd be hard pressed to find an LP with a full 1" maple cap. I can't help but wonder about the authenticity or modernity of the drawing if it's asking for 1". As for Setch's chambering, there's no reason that just because Gibson does a solid body you can't improve (or "modify" if you don't consider it an improvement) on their design! No need to follow Gibson's style slavishly. A lighter LP is a good LP. <grin>

Greg

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