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Since the image uploader is fixed I thought I'd throw up this on how I cut lapjoints. I first saw this jig on Charlie Hoffmans site.

The jig for this took at least 5 minutes to make and probably another 10 to adjust for the X angle I wanted.





Clamp it to the bench and measure the X braces and mark where the joint should be.

I use an 8mm router bit for dreds and larger and a 6mm bit for smaller OM/OOO type guitars.

Thickness your braces so that they are a little thicker than final dimensions.



Clamp your braces to the underside of the jig with another 'sacrificial' piece of wood to stop tearout.



Adjust your router to the appropriate depth and cut.



Next is to run the brace through the thickness sander to bring it down to final dimension and a tight fit.



Voila. Perfect joint.



This one is for an OM back brace @ 8mm



I know some people will find it quicker to do with a hand saw but this method is really foolproof considering the critical nature of this joint.

I also do a run of X braces while I've got the jig set up so there's about a years supply in the shed at the moment.

Cheers

Bob

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Bob Connor
Geelong, Australia

Excellent! Thanks Bob,
By the way, do you radius the brace bottoms before or after cutting the lap joint? If after, how do you do it?

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Lance@LuthiersForum.com

I radius after Lance.

I have a jig that will radius on a router table or a pattern sander.

Of late I've been sanding manually on a radius dish.

It only takes a little longer and there is no danger of tearout like on on the router table.

Bob

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Bob Connor
Geelong, Australia

One question with the radiusing of the brace after if I may Bob. Are you worried at all that the radius will not be uniform due to the fact that the brace has the lap joint cut out already. The brace would tend to flex more in that area which may cause the radius to be irregular.

I certainly do like this method and plan to "steal/borrow" it from Charlie in the very near future.

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Good Job Bob. I have a similar setup, and I too copied Hoffman.

Bob, will you play with a set of these loose braces and see if you can get it to assemble at the wrong angle?

Mine will and I have to be careful to get them right.

How about these pictures? !

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http://www.dickeyguitars.com

I've noticed that too Bruce.

It's very easy to assemble them the wrong way.

Yes, the picture upload thing being back on is super. I've had these pics sitting here for about a month waiting for it to be fixed.

Rod - I've got a 15 and 25 radius gauge that I check them against after sanding.

I find that I have to be careful not to sand too much off them otherwise the lap joint won't be snug (in a vertical plane) Hope this makes sense.

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Bob Connor
Geelong, Australia

I did a dozen last time with adi, only to realize that the angle could be wrong. I'll never forget that experience. Thin super glue in the joint holds very well, very fast.

The idea was to make it easy.....

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http://www.dickeyguitars.com

Saw your image and I hope this works.

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Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

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http://www.dickeyguitars.com

This is my little jig.

A couple more pics here.

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http://www.dickeyguitars.com

Cool Bob. Thanks for sharing. How tight are these using this method? Squeeky tight?

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

[QUOTE=Brock Poling]
Cool Bob. Thanks for sharing. How tight are these using this method? Squeeky tight?[/QUOTE]

I would think the tightness is a mater of how carefull you sneak up on the thickness of each piece with the drum sander. Pretty cool method me thinks, thanks for sharing.

I rough shape the bottom of the braces before I join them and then sand to whole x in the electric dish after. This insures that each piece of the x is square to the world, or perpendicular to the top.

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Tickle your guitar daily, and it'll tickle you back.

Absolutely correct John.

I guess you could 'sneak' up on them with a plane or sanding block or a scraper for that matter.

I like your idea of sanding the X whole.

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Bob Connor
Geelong, Australia

Very clever solutions, guys. Thanks!