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Would you mind sharing your technique for cutting the X-brace lap joint?

I've considered using my table saw. If I lay both legs side by side against the miter gauge and cut both slots at the same time on the table saw, once I turn one of the logs over will that slot be angled the right direction?

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Formerly known as Adaboy.......

I don't own a table saw, but that is how I do it with a hand saw so I don't see why it wouldn't work. . .

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I do it by hand as well. I made something similar to the fixture shown here: http://www.kennethmichaelguitars.com/Xb ... guide.html

It was easy to make and works great.

Seems like a lot of trouble to remove such a small amount of material. I've had pretty good results so far just cutting each piece by hand with a little exacto saw and using an angle gauge to mark the cut. Knock out the waste with a chisel. I cut slightly undersize and then use a flat file to sneak up on a snug fit. Unless you were doing dozens of these a day I don't think jigging up saves you any time or much accuracy.

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Jonathan Kendall, Siloam Springs AR

I agree with the above post.

I transfer the angle to the braces with an angle guage, and then flip one over, so that you can cut them both at the same time with a razor saw, clear with chisel. As above also, I cut them inside the lines then file to fit. It works pretty well, and you get a nice fit.

Great, if it works for you. I've done it that way as well. Getting a good, tight fit is pretty easy, but ending up with exactly the x angle I wanted is not so easy in my experience, since the slightest variation of the angle at the intersection can transmit to 2 or 3 degrees at the lower ends of the braces. A nicely fitted joint looks nice and is structurally sound, but if your x angle is off that affects tone as well. The jig removes any error in the angle and results in a perfect, tight fit.

I do it by hand and I make the cut a little too small for the brace to fit into. Instead of sanding the cut out to make it bigger to fit the brace, I sand the side of the brace to make it a tiny bit smaller to fit the cut. When I used to file the cut out to make it wider to fit the brace, I tended to get it out of square. Sanding the brace thinner with 220 lets me get the fit tight as a frog's back side without going out of square or changing the angle of my lap joint.

Darryl,
I saw on that other forum where CET's post with the link to the KMG jig was removed. Thats a terrible practice, but kudo's to you for saying something about the editing of posts over there.

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http://www.CostaGuitars.com
PMoMC

Darryl : I do mine on the tablesaw and find it's much easier to do then by hand. Take a couple of pieces of scrape the same cross section as you X braces and set up the saw and practice. Leave the notch a few thou.short of going together.Don't take your braces apart to try but measure with dial calipers. Then give them a rub on a bit of sand paper to fit and I think you"ll have a better job then by hand. Fit will be perfect and angle will be dead on.Takes me a bit at the saw to figure out the angle etc. but you get around this quickly with the test piece. Let us know how you make out.
Tom

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A person who has never made a mistake has never made anything!!!

I do it just as describe by MikeyV

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http://www.Harvestmoonguitars.com

I have made them both ways. One shop I worked in we made enough braces at one time for maybe 10 guitars or more at a time. Had an old table saw set up with daddo blades stacked just right for the joint. The other shop I worked in, we did them in batches also, but used a blitz saw to cut them after marking them.

I do the hand cut because I don't have a dedicated saw nor room for one. Use a jig for angle as noted above. By the time I would set a rig up for a table saw, I can have them done. But I am sure there are those with good jig it only takes a moment to setup and do and have them done faster than others can by hand.

So depends on room you have, tools you have and how you want to set up for this task.

I only have the cheap miter gauge that came with the saw. It has clicks (supposedly 1 deg increments) and is a little difficult to set at a half deg increments (and I doubt it's very accurate anyhow). I'm making a Norman Blake style 00 and measuring my drawing the X brace is at 95 deg. so I need to set my miter gauge to 2 1/2 deg which means I have to fight the "clicks" to get it right (it's difficult to stop in-between clicks). Just tried it and it was close but not exact (on scrap).

I have to go back to work so tonight I'll either fight the clicks or cut by hand. Might make the jig described to keep alignment for hand cutting, not sure. I'll see how well I do on scrap and decide.

Thanks for all the suggestions!

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Formerly known as Adaboy.......

If you need a 95 degree angle , then you set the gauge to 5 degrees off 90 ..... I use the table saw to do mine as well. I mount two diablos, with a Forrest stiffener and the right amount of Lee Valley dado shims between them to get the spacing just right, so it cuts and leaves the notch a little snug - knock the centre waste piece out to get the notch, then a pass or two with the plane to fit and they are perfect.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Ya, don't 1/2 the angle. You need to set the gauge to the proper angle. Think through the cut and you'll see that the cut needs to be at the exact angle you want to achieve.

I cut on table saw too. I cut my angle to 1/4" and then sneak up on the joint by running the brace through my sander...

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My Facebook Guitar Page

"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

I don't see a need to go to the table saw to make a couple of cuts that are faster and easier to make with a Dozuki and a chisel.

-jd

This works like a charm:


http://www.bridgecitytools.com/default/tools/gift-ideas/km-1-kerfmaker.html





Best regards,


Edzard

this isn't that difficult of an operation. A nice trick to control the depth is to clamp a stop so you don't cut deeper than you want to. A wood file and clean things up in a hurry . Many cute jigs for this and most work well .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

cheater! :p

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Jim Hansen

It works make it simple . Sandpaper glued to a stick makes a good fitter.

Using a table saw is great for multiple braces. I use a fine blade and you can use the rip fence for a stop. I am making braces this week and can show this technique. I agree if you are making 1 set or 2 learn to do it by hand , it is a good skill to have .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I've always had trouble getting my saw cut perfectly perpendicular to the base of the brace, and even depth of the cut was always poor too, as well as popping the notch out with a chisel seemed to tear out some wood at the bottom of the lap. Then fine tuning it all with a file..... I was never happy with the joint that I produced, which is why I switched to the table saw. Depth of cut is easy to set, angle is easy to set (measure on drawn out plan or top) on the mitre gauge, and cut to 1/4" wide (or how ever wide your brace is) is the only fine tuned aspect.

Everyone has a good method that works for them. Some like the table saw, some like doing it by hand. For me the table saw netted more accurate and tighter fitting joint, even for one off. Had nothing to do with the time required to do it.

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My Facebook Guitar Page

"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

I mark mine, for both angle and width then clamp them together in a vise and cut with a small saw.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Table saw very fast, accurate and tight fitting. Use your angle gauge and your off and running.

Lance did an excellent tutorial on this a while back. Works beautifully and you can make more than one at a time.

http://www.luthiersforum.com/forum/viewtopic.php?f=10117&t=15971

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Dan

After reading these suggestions, I decided to try using my dado blade set. One pass through the blade appealed to me as I didn't want to get the channel too wide. Had to add a thin carboard washer (included with the dado set) between the two 1/8" outside cutters to get the right fit but it worked fine.

I'll probably start another thread to discuss another issue I found with my brace radius........but here is a picture of the X-Brace laid over the plan I drew (00 based on a Norman Blake 000):

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Formerly known as Adaboy.......

I use my router table and a mitre guage , for 1/4 inch braces, I start with the braces slightly wider than a 1/4 inch, cut the slots then sneak up on the thickness with my thickness sander...perfectly tight fitting joints...

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MK5acoustics.com

Dan, thanks for sharing the link to Lance's tut! I may use a similar approach in the future.

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Formerly known as Adaboy.......