Brian Howard's guitar building & repair blog: The Bondo Cutaway Or Why I hate bondo on guitars!

My patient this time around is a 59 Gibson ES 125. This guitar can tell some stories too. The current owner is the son of the original purchaser. But the guitar was not handed down directly. It was sold by the father and tracked down by the son after his passing. In that time the guitar was used, abused, repaired, modified and gigged pretty hard. What started out life as an ES 125 TD showed up at my door as an ES 125 TDC……C meaning cutaway. I had been informed that a cutaway was added to the guitar before taking the job and expected some debauchery. But in the photo’s the work looked fairly clean, even if it was buried under mass quantities of black enamel. It also suffered a broken headstock, which had some type of repair lurking deep under some type of filler…….The top was partially stripped, but done very roughly with a pad sander. Our goal was to restore the guitar to its former glory.

My first exploration was of the neck break and subsequent repair. The filler was bondo……..Let me say, I hate bondo on wood! Repeat that! Don’t use bondo folks, there are proper products for restoring wood. I will show some later. Of course when I found what was lurking under the huge blobs of filler the choice of bondo was less surprising. The neck repair was mostly mechanical consisting of 3 screws with inverted trim washers partially countersunk into the face and a steel plate with ground down nuts on the reverse. A truly bad cover up of a lousy repair. Yes it was functional, but that’s the only good part. The entire neck had been faired with bondo and something even worse……..lacquer spot putty! Sigh…….

The cutaway turned out to be just as brutal. First I decided to strip off the black enamel. I used a heat gun and a putty knife. And I discovered more auto body work there as well. The cutaway however was something to see. It was constructed on the surface at least entirely of bondo……… Under all that bondo there actually was some wood. Chunks of something glued in to support the plastic filler.

First I opted to repair the head break. After getting all the bondo off and removing the hardware I ran the headstock into a drum sander to prep the back for a back strap graft. Here we can clearely see the original fracture line, the 3 bolt holes (filled with sanding dust in this pic) and as a surprise bonus two wooden dowel pins. You can also see my main concern with the original repair, the wide line of glue & filler at the joint of the break. The person doing the repair obviously lacked the proper clamps to pull this back together. This could have been glued up the first time as to have been barely noticeable….. The dowels and screws actually served to weaken the joint by seriously limiting long grain glue surfaces.

Despite all this it was stable and the alignment of head to neck was fairly good. The tuner holes had all been hogged out for modern cast tuners and there were evidently some small chips of the peg head face lost in the initial break or the subsequent repair. I reamed the tuner holes true and glued in mahogany plugs. In this view you can see the break from the front after the holes were plugged.

I glued a new back onto the headstock. Kind of like a backstrap except much thicker. Too thick to make the bend at the heel as would usually be done. So it was fitted in to the curve from straight on and a second layer was added to build the heel back up to where it could be shaped properly. The heel is roughed in using a cabinet maker’s rasp. Gibson peg heads are not a uniform thickness either, they are slightly thinner at the top than at the corners of the hyoid. So I shave a shelf at the end of the head with a chisel to about .015” of final dimension, just enough to allow for sanding. I then chalk the shelf so I can be sure not to cut it down any farther. The large piece glued onto the back of the peg head was cut to give this same .015” over dimension before being glued on. So now I just pare away between the two elevations with a crane neck chisel and I can carve the transition to the neck.

The face of the peg head still needed quite a bit of work. There were big chips at the edges that had been filled with……you guessed it, bondo. The break was also very nasty on this side. So I decided to put a face plate on as well. But I needed to cut out the bad spots at the edges and lay some new wood in there. No filler or putty will ever hold up well in places like that. I also needed a solid and flat surface to glue the headplate onto, so to fill in the cracks and make a level surface for my face plate I use a product called Famowood. I use the solvent variety and not the water based as I find it matches and blends better when it is exposed. Once all this is done a .030” face veneer is glued on and the proper size tuner holes are drilled.

With the neck and headstock squared away it was time to turn my attention to the cut away. First I had to dig out all the bondo…….Under which I found chunks of Cherry Crudely shaped and wedged/glued in to support the bondo. It was decided that I was to proceed with constructing the cutaway from wood rather than the easy route of just re-filling and painting the rim of the guitar an opaque.

So the wood blocking needed to go. To remove it without causing any more damage to the body I bored as many holes through it as possible. I call this the “Swiss Cheese” method…. The blocks can now be collapsed in on themselves And carefully pared away from the body. They were infact glued inb and what was lacking in good tight fit up was made up with extra glue.

Once the blocks are removed I true up the top and back which were cut slightly off from each other on a drum sander and sand away the glue and dirt inside so I have a clean fresh surface to build a new proper cut away on. At least the person to actually do the job the first time didn’t mess with the bracing and cause any damage. The back had also been split up a bit from pounding one of the blocks in so this was cleaned and repaired at this time as well. Another problem to address is the neck block. The bondo king did not know how to deal with this so he left it exposed after he cut it. You could clearly see all the plies in it even through all the nasty black enamel. So I once again turned to my crane necked paring chisel and carefully cut the block back so the new rim could fit over it and still be flush to the neck.

A set of paper board templates was made of the shape of the pieces I needed. I am doing this in two layers to add some strength and match the laminated construction of the guitar a bit better. I then cut two pieces of mahogany to these shapes and carefully bent them to the correct curve on my hot pipe. These two pieces are then glued together to form the new rim for the cut away. Notice the inner one is notched to fit around the bracing so it winds up tucked into the rim for the most solid connection I can make.

The new rim is then carefully glued in at the headblock and the point, just kind of floating between. This must be done very precisely as when finish it should already be rebated for bindings. Installing tradition linings without removing the back would have been an extremely tedious and time consuming affair. So instead I made a pile of lining blocks as some classical builders still use and glued them in individually. The ones I could reach and see through the pickup hole were done with a small brad as a handle and some surgical tools. The others were stitched in with a piece of nylon string.

All the bindings were then replaced and scraped then it was time for the finish work. This was done in a nitro lacquer. The original burst was one with a cherry red around the edge. This would have been too transparent and showed some scrapes and other damage around the edges caused by previous finish stripping and a bad rebinding job. The owner also preferred the older style tobacco burst and this instrument would have been right at the transition between the two finishes anyhow. So that is the route we went. The back and sides even after stripping and prep still had a majority of their original stain intact, so that was saved and I blended new matching stain in as needed. This was mainly around the edges. The neck was sanded just enough to remove all the amp rash that had accumulated and stained as well.

Another really cool thing about this project was the wiring. The original wiring harness was still mostly intact! The volume pot on the neck pickup had been replaced at some point, likely in the 60’s and a section of wire to the jack had been spliced in quite questionably. I replaced the section with a new one and that was it.

Here it is after final assembly. It has new stainless frets, a bone nut, Kluson tuners and tailpiece and a nice reproduction pick guard. A really awesome old guitar brought back to its former glory and ready to make the world sound better. Have a listen with the video at the end.