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Well, I started off Radiusing my braces in the radius dish. It was effective, but for these reasons I searched for a better way.
-Took a lot of time and elbow grease.
-Occasionally skinned a knuckle or two on the sandpaper.

Then I bought the Brace Radius jig, but honestly don't like the design. For these reasons:
-More times than not the jig won't hold a brace down in the radius. It might hold it for a second, but it slowly slides back up and I'm getting tired of battling with it.
-Waste. Because you're running the brace across a jointer, it must be a given height to be able to clear the jig. Often this is a big waste of brace material and probably kills almost twice as many trees as needed.
-Width limitation. While most of your braces are usually within this width, I occasionally have a brace that just wont fit in this jig.

I'm looking for either an alternative solution to brace shaping that is easy to do, effective, and doesn't require a lot of elbow grease.

OR

A solution to getting the Brace Radius jig to at least hold the stinking brace down like it was intended to.

Thank you all in advance for your thoughts and ideas.

(PS If someone who can delete posts wants to head on over to the video and picture tutorials forum where I posted this about 100 times, please delete them)

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

Blain, do you have a router table? Even a small make shift one? If so, consider making a jig to radius your braces on that. Piece of 1/2" plywood with the radius along one edge. A couple of dowels to position the brace and a couple of hold down clamps (these don't have to be expensive either). Use a flush cut bit in the router and your done.

Or, you could do this (find my post in this thread) on the table saw. I think I've posted this method 3 or 4 times now here...

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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

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This is my first build but I used a very sharp block plane. Seemed to work well but I guess I'll find out when I finish assembling it.
Good Luck
Mike

I use a jig based on one that Sylvan Wells uses. On mine, the center stop is drilled off-center, so I can dial in different radii, requiring only one jig.



Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

Sweet. Thanks Guys.

Rod, I do have a router table. I think that is exactly what I'll try to do. Thank you!

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

Do you have a plane? If so, this is the simplest and best method I have tried.

I trace the radius of the domed sanding dish onto the side of the brace, and plane to this line while with the brace held in this simple jig. The last passes with the plane is along the whole brace, to get a continous planed gluing surface. It is surprisingly easy to plane a curve that matches the radius of the dish, so I’ve abandoned the routing templates I was using for a while. This method is not only faster, it also gives a superior gluing surface.

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Rian Gitar og Mandolin

Hi Pat,

This one is just not apparent to me. Can you explain how it works?

It appears you're deforming the brace stock (by pulling back on the middle, with the ends stopped), and then clamping down the center, then cutting with the sled. I can see how that would create a radius (when the wood springs back), but can't see how it would cut a radius of any specific, repeatable dimension.

So, I'm sure there's something I'm just not envisioning.

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

Jigs such as Sylvan's or Pat's do not create a brace with a radius (i.e., circular) curve. They create one with a spline curve, which may be close, but is not circular.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

This thread kind of highlights a bracing issue that I've been contemplating for a while now also.

That is, let's say you're bracing a guitar back using a 15' dish. If you just radius the braces using a plane or router technique, they end up with a 15' curve on them that's parallel to the flat top surface of the brace. When you glue the braces onto the back in the dish, they end up perpendicular to the dish surface, so, (the top and bottom ones in particular) they will end up looking like they lean towards the center of the dish. This is not pretty when you look at the bracing through the soundhole.

To overcome this issue, after radiussing the braces (I use a marking template to draw a pencil line on them, then plane them - just like Arnt shows in his posting above - very fast indeed), I sand them in a dish in the actual position they will be mounted in when glued to the back (or soundboard). This works well - you end up with braces that all look vertical. However, the sanding operation is extremely tedious - it's quite difficult to keep the braces vertical as you sand them - and the rough sandpaper is fairly hazardous to ones finger tips! I've been thinking of making some kind of brace holding jig for this operation. Has anyone done this already? Got any pics?

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

I did an exaggerated drawing to show what I'm talking about in my posing above:



HTH,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

I ask myself whitch would be the better support for the plate........?
My instinct is towards the former.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Dave buddy I completely understand what you are describing and concur too. I posted about this several years ago and indicated that I too will mark the actual location of the respective brace in the dish and then sand it as close to that location as I can. Doing otherwise and they lean AND even though the degree is mouse nuts the profile on the bottom is ever so slightly off unless the brace happens to be destined for the middle of the guitar plate and it also happened to be sanded in the middle of the dish.

I was shot down in flames over the mention of this and everyone, except Coach Tony if I recall maintained that sanding anywhere in the dish produced the same profile so it didn't matter.

The leaning issue can be overcome simply by shaping the brace not to lean but I still maintain that sanding in the respective location in the dish that the brace will go makes for a better fit.

BTW I just can't remember where I learned about this but it's not an original idea on my part, nothing generally is..... and I believe that it may have come from Frank F. and his video series.

Anyway I profile simply by tracing the desired radius onto the brace stock using one of Tracy's excellent radius templates from Luthier Suppliers (link above) and then hit the brace on the belt sander - very fast! Then I sand in the dish (yeah, yeah I still sand in the respective future location so there.... ).

A tip that I think that I did come up with is if your particular brace is subject to flexing when dish sanding possibly because of an over zealous sander/person... tape two like brace stocks together, one on top of the other like the buddy system with a broken finger. The flex goes away and you get the true radius sanding into the brace and it's easier to hold on to.

If you sand the brace perpendicular to the bowl, then the ammount of lean for braces 1 and 4 on a ladder braced back is about 1 degree .... thats very easy to get rid of when planing the shape into the brace, thats what I do...

About what Hesh said .. if you are not leaning the brace that one degree in the bowl as you sand braces 1 and 4, then you are getting the exact same effect/bottom edge as sanding in the middle of the bowl. So are you good enough to lean the brace only one degree and not two ??? Are you really getting a better fit than a planed bottom ??? I know I am not. I will take the planed edge over a sanded one any day ... and as for the flat edge vs the slightly rounded one you are getting by sanding (again, assuming you are not rocking at all and actually making it worse) .. its about a thou across the brace bottom, about the thickness of the glue ...

BTW .. I use my shop buitl version of the radius jig .. I coulnd get my wider braces to fit either, as it will only hold something thats about .440 wide ... not the aadvertised half inch. Mine has 80 grit sandpaper as a hold down, and the brace doesnt move .. cut on the TS, then cleaned up with a plane, I can make enough braces for 5 guitars in about 20 minutes, all ready to glue ...

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

I rough shape my braces either with a jig like Tracy's or a plane, then sand in place on the dish. I find trying to sand the braces gives me two difficulties. First, I get hot spots. It sands more aggressively where I hold the brace. My other problem is trying to keep the brace vertical when sanding not in the center of the dish. I made a little brace holder to help distribute my pressure more evenly and give me a larger thing to keep straight. My shop is presently a disaster, so I can't post a picture, but it's essentially looks like a little version of Tracy's jig (straight backed, not radiused) with a thumbscrew and a scrap of back to keep the screw from denting the brace. I just cabbaged it together on the fly one night, so it's more of a hassle really, but it does work and is easier to hold. I like Hesh's idea of stacking a couple of braces. Quick. Easy. I'll definitely try that next time.

Edit: Oh and Howard, thanks for that. I'd never heard of a spline curve. Cool.

Mike

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Mike Lindstrom

I bought a brace maker as I needed something to do the job.. I have only used it for one back so far so I can't make too much of a comment. It does spring back a fair bit if you use too wide or too tall of a brace. What I found myself doing to save wastage was to cut my brace wood on the table saw to near the perfect height needed to fit in the brace with enough over-hang to level it off.

One way of doing it under brace radius

http://www.youtube.com/user/closetpicker#p/u

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Formerly JJH

I learn more from my mistakes than my successes

It's funny how times change. I asked this question a month ago & didn't hear much, now there are all kinds of interesting answers.
I ended up taking my 15ft. male radius curve & made a matching female curve & clamped that female curve to my bandsaw with a little notch cut out for the blade, so when I ran my male curve against it, it did not damage it. Then I put a fence & stop on the male curve. I dropped the brace on it & fed it against the fence & it cut the curve very fast. Then I lost patience & sanded them anywhere on the dish.
I figured last year it would be better to sand on the dish where the brace is actually going & vetical but I don't care right now. I would like to see the math on this to see what we are talking about.
When I get to the top bracing I think I will sharpen up th plane & do the final clean up that way. I agree with Tony a planed edge is better, (flatter & a better glue serface)

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Mike McNerney

Arnt,

Is a plane cut superior to a routed one? I always figured they were similar since both were cut, not sanded.

I use a router jig and scrape the bottoms along their whole width with a sharp blade before gluing.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

Howard,

That's true. If I check by sanding in the radius dish, I get full contact, so I guess it's pretty close.

Pat




Dennis,

When the brace is put into the jig and pulled back, it approximates an arc. The table saw makes a straight cut, then when the brace is released, the straight cut becomes an arc. The hole in the center stop is drilled off-center, so that turning it to different positions alters the amount of sag in the arc so that one jig works for both my top and back bracing. I've marked the positions for the two radii that I use; one of marks can be seen in the photo just in front of the toggle clamp.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

Wow! Lots of answers. I was curious about these jigs so I bought two of them One of them was purchased from a local luthier going out of business. It has the toggle clamp in the middle that holds the stock in place. But it doesn't hold very good. Then I bought the jig from luthiersuppliers, and it works better. I had to put some sandpaper on the plexiglass to get it to hold the 12' side (I got the 12/25). But even after I cut it, I have to put in though my radius dish to fine tune it. I think the stiffness of the wood effects the accuracy of the cut. I have not done one yet that was perfect right out of the jig. But it does save a lot of time. Once you get all the wood ready, you can mass produce the braces. Anyway you look at it, they are a pain to produce. I wish there was a cheap source for good quality, un contoured braces.
Mike R.

Well, in theory it is, since a rotary cutter will leave tiny scallops and the plane makes one long, continuous cut... I'm not sure if it matters if your router set up is working perfectly, though. I do know I can easily get better results with my plane than I ever did with my router table. As a bonus it is faster, quieter, and produces less dust. What's not to like?

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Rian Gitar og Mandolin

I do my differently-I can make all 4 back braces in around five minutes.

First I take a quartersawn blank 3/4" high by about 1-1/2" wide by the length of the longest brace.

Then I use the radius dish to draw a pencil line on the edge of the blank and bandsaw almost to the line.

Then I sand it to the line on my 6 X 89 sander with the 90 degree table (check to the dish) then I set the bandsaw to cut out 4 pieces a little over 1/4" and cut out the 4 braces from the blank.

Then send through the wide belt(or drum sander ) to desired thickness-DONE

I know this doesn't take into account the curvature of the earth (dish) but I don't notice any difference in the finished domed back.-If you wanted you could still sand to the dome as the last step.

For me the beauty of this method is that I don't really have to handle the 4 pieces untill the end.

My method is very similar to Hesh's - although I made my own radius jigs out of some dogwood I had. Hard as iron.

I simply place the template brack on top of the spruce brace, trace the relevant radius onto the brace, plane back to the line, and touch up on the radius dish. Still needs a bit of elbow grease, but not much. And yes, I try to sand it on the relevant place on the dish, so as to avoid the "leaning" appearance. Seems to work.

I made a jig that has the radius on the edge and clamps to hold the brace in place, and cut on the router table with a pattern bit and touch up on the radius dish. The jig didn't take much longer to build than it would have to sand a couple sets of braces, sometime I get a little chip out at the ends so I leave extra length when cutting.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I have seen many versions of this jig but Pat, I think yours, with the adjustable radii, is the coolest. Good job!!

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