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I have 3 spots where the side material tore out while cutting the binding ledge. All similar to the attached picture. I was wondering what the best way to fix this might be? I can bind then fit in little pieces and finish to match or repair before the binding goes in. What's the best method?

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Common problem, particularly around the lower bout. Best thing to do is to bind the guitar, being sure to have a black line on the bottom of the purfling scheme, use the CA binding method, but wait to do the final pass with the CA along the sides. Come back with some fine sandpaper making some sawdust with the adjoining wood and fill it, hit it with superglue, level, hit it again, level. This will mostly go away on darker woods.

Thank you. Yeah it's around the lower bout - that's the plywood tail block visible in the pic. I'll try the technique you suggest. It's walnut BTW.

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If you can find the little piece you can CA it back on are reroute that area as well. When ever I am routing something I try to keep an eye out for large pieces that may shoot off, so I can find them to glue them back on.

Very small piece on a floor covered in saw dust and chips - not happening, but thanks for the tip.

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Hah! Funny, as I was fine tuning the purfling/binding ledges I found another large (2" x 3/8") piece that had been torn out. Looked all over and finally found it over by the car about 10 feet away. Glued it in, cut the ledge by hand and will finish repair after binding. Looks like crap now and disappointing/frustrating but may clean up OK.

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That's a big chunk of tearout. Are you following the climb cut pattern as found on the stewmac site?

IME the best way to deal with this sort of thing is to make your own splinter, shaping it by teasing with a needle or something until you get a reasonable fit. Soak it in some hot hide glue and clamp it in hard to smoosh it in place. Let it dry and chisel flush.

I strongly disagree with the use of CA for this repair. Likewise, don't even think about glue and sawdust. I cringe every time I hear someone suggest this.

Walnut is fairly forgiving because of repair like this can be disguised as variation in the grain and pore structure if you are careful.

Small tearouts are best dealt with by filling with clear burn in lacquer stick. This is usually invisible.

I agree with Greg. If you can't find the original piece of wood, find some of close color on your
Back/Side cutoffs and make a piece to fit. If you follow the grain lines, you can even enlarge
the tearout a little- making it a small triangle, and then make a piece to fit. Because it's a little
larger, it's easier to shape. Doesn't matter if it sits proud of the surface, you can sand that
off after the glue cures. I don't like the sawdust & CA mix because it almost never matches
the surrounding wood color (but as dberkowitz says, it can sometimes work with darker woods).
I like LMI white or fish glue. The LMI dries clear, and the fish is a brown/amber that works well
with most woods.

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Gene

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I have another right at the corner of the end graft - looks awful - and this will require a custom little piece so I'll probably build more as I get the technique figured out.

Yeah more tear out than I've see before - like none on previous builds. Maybe a dull bit and definitely some very brittle wood.

Yes I did follow the Stew Mac guide for routing.

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Glue and sawdust does work well for very very minor gaps though. I agree that CA is not the best choice because it will show the glue line.

Looking at your soundboard, there, Larry, seems you have some pretty dull tooling. Not much help this time around, but a new cutter or a touch up of your current one (and climb cutting) would help avoid for next time.

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I got in the habit of using a gramil before going to the router. (next time) Clinton

Wood is walnut and figured near this end of the git but all the advice is good and will be heeded next time.

I used a combination of all the above techniques and I think it will finish up fine. If some of the fills are too visible I'll go back and fill where needed with wood but the CA worked pretty well in the smaller areas, areas too small IMO to fill with a piece of wood. I'll epoxy fill soon and will know then what worked and what didn't.

Thanks again for all the advice and timely information.

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Fillipo, two thoughts. First and foremost many of the folks on this forum are new to woodworking and struggle to get through their first instruments. While a splice repair would be preferred, many of them have enough trouble getting the basics down let alone what is not an easy repair for the uninitiated. I suggested a very common repair technique, ubiquitous in the community. As you and others pointed out, it's not the right repair in all circumstances, and I wouldn't recommend it on something that went further down the side or as I already pointed out lighter materials, but it's hardly the sin you suggest.

Second, when we talk about climb cuts, it's a climb cut relative to what -- the plate or the side? That part of the body is problematic for chipping both on the plates and the sides because of the changing grain directions. Approaching the plates has runout on either side of the apex of the lower bout, as well as on the sides where it's common to have the short grain runout as shown in the original post. It's not infrequent to have some chipping on the sides in this location. Even cutting the ledge in sections, i.e., the ledge depth without the purling, and a second pass deeper for it, can see problems with chipping and with brand new bit's. It used to be that the common repair was to fill chips and binding gaps with stick shellac. I've found over the years that for the most part the CA repair is less visible than the shellac.

As much as I strive to have as little to adjust as possible, there are always going to be the inevitable repairs in the course of building. 80% of building is doing the basics and 20% is covering the inevitable hiccups made during the first 80%. It's wood after all and there is no escape from its vagaries.

A climb or conventional cut depends only on how the tool is engaging the material to be cut. Using a climb cut technique will climb cut both the plate and the side.

http://www.cnccookbook.com/CCCNCMillFee ... tional.htm

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That was a very informative post. There were answers to questions I didn't know I had. The walnut sides that chipped were indeed quite figured, very brittle. and may have contributed to the chip out. There was fairly bad chip at the end graft that I cut a piece to fit and smaller chips there I CA filled. I'll post the guitar under finish when it's complete and see what the various ares look lke.

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Andy, I disagree. There are two relationships to the bit, the relationship of the rotation of the bit to the grain of the top and the same with regard to the side. They are not the same climb cut. In the current example, one would cut from the apex of the bout away in both directions to reduce tear out in the plate; however, that is not a climb cut when cutting the side as you are pushing into the short grain as opposed to away from it.

http://www.finewoodworking.com/how-to/a ... ayers.aspx

I have never heard a definition of climb cutting that is not as the above...

I have made it a near 100% routine to first climb cut all routes and then go back with a conventional cut to clean up any furring of the grain...

I look at it like this: using a conventional cut (often considered far safer to the operator of the hand held tool) the rotation of the leading edge of the bit is pushing material away from it's edge at 90 degrees...this can many times cause blow outs...when climb cutting the material is for all intensive purposes being compressed into itself...except in cases where the material is severely flawed, climb cutting has a very low % of failure (taking the caveat that the operator has the tool firmly held in his/her hands)...

climb cutting can result in more burning on total end grain, but in the case of a binding ledge this is of course covered up and therefor a non-issue

It seems like 'climb cutting' is defined by a couple of factors. One is the rotation of the bit in relationship to the travel of the router. The other is the relationship between the rotation of the bit and the direction of the wood grain. According to this definition a climb cut tends to 'compress' the grain and the other type of routing will 'lift' the grain and increase the chance of tear-out..

With my Bosch Colt router the rotation of the bit defines any clockwise movement around the outside of a guitar as a climb cut (I think) but only along certain portions of the top and sides will this direction of bit rotation router movement 'compress' the grain. In other areas it will 'lift' the grain as you travel from bout to waist to bout. Of course that's the rationale behind StewMac's routine of routing binding channels.

Along the sides a classic 'climb cut' will, again move in the direction of the router bit's rotation but the grain direction can change from area to area. Is it still a climb cut if the grain's direction cuases it to lift? If you use just the bit's rotation then yes. If you take into consideration the grain's direction then what?

So it seems like the term can mean a couple different things and it seems with a figured side where the grain direction change quite radically it's a bit of a crap shoot whether you are truly climb cutting or not. I'll pay more attention to all the factors next time I route bindings.

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It's only defined by the rotation of the bit and the direction of the feed with respect to the rotation of the bit. The grain of the material does not come into consideration when defining whether or not you're climb or conventional cutting. Look at the drawings in the links above.

With the guitar sitting on your bench face up with the router pointing down - feeding the router clockwise will result in a climb cut, counter clockwise in a conventional cut period.

Typically speaking, a climb cut will result in much less blowout compared to a conventional cut.

http://www.stewmac.com/freeinfo/Routing ... -1298.html

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Thanks for that link Mike.

Mike, does that mean you route in a clockwise direction around the entire guitar first, no matter the grain direction? Does anyone else do this?

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http://www.newenglandluthiers.org/conte ... g_Jig.html

go to the bottom and read using the jig...

I think it's six of one and half a dozen of the other...

climb cutting exclusively deals with the issue of hard wood sides...a combination of climb cutting and forward cutting deals with the grain of the top (usually a soft wood)...

I think softwoods cut/route easier than softwoods, and barring a 'defective' piece of wood, climb cutting results in fewer blow outs...

as a note I learned of climb cutting many years ago...tended to not use it because of the difficulty associated with using it in general wood working where typical routes remove a fair amount of material (hence making the router want to fly out of control)...then came a period of time where the material being supplied in the field (as a trim carpenter) was some sugar pine that was what I can only describe as being stringy in its grain structure...when forward routed the result was tear outs in the routed profile (not on the edge, but the whole profile), when climb cut it would furr up but leave the option of being sanded...so at this point I started to use the climb cutting method even though it was more difficult and more time consuming (climb cut on one pass slowly, and maybe even doing 2 or more passes as needed because of the amount of material being removed, and a final pass in the traditional direction) as in the end arguing this or that made no difference to the builder/owner of the house...the desired end result needing to be a finished product that was nice and smooth...in general the painter is not paid to fill a bunch of tear outs in the wood, and while I could of course argue it was the inferior wood, I can guarantee you that argument (while totally true) didn't work...in the end it was best to climb cut, sand a bit (and let the painter do any final sanding to full smoothness after the surface got primed) and make everyone happier...yep even myself as I certainly don't like a builder who is supplying regular work being unhappy with me...

I find that taking your time and using SHARP bits will dramatically reduce grain orientation issues when climb cutting...the same cannot be said with as much surety for forward cutting...

there are many 'happiness is' lines out there...as a full time wood worker since '86 (and part time/hobbyist for most of my life) my version of 'happiness is' are VERY sharp tools...second to that would be power saws with no bearing run out which (because of various factors) is becoming almost impossible to find these days

I first rout around the entire guitar in a clockwise direction (climb cut). The reason you get fewer blowouts this way is because the router bit is taking smaller bites of the material. The bit does tend to push itself out of the work so a firm hand is required on the tool.
A sharp bit and a cutting edge on the bottom as well as the side of the bit will help minimize blow outs on the sides.