Using Cleats to Repair Side Cracks on the Gibson TG-1 Guitar

In our last episode, I glued the top and side cracks on the Gibson TG-1.  Now I'm going to make some cleats to put behind the side cracks for reinforcement.  The cracks aren't too bad, but since they're about 3 inches (75mm) long, I want to make the repaired area strong so the cracks won't open up if the guitar takes a hit to the side.

I have a nice piece of mahogany for bracewood that I've been using for these kinds of repairs.  I cut off a hunk of it.

Then I stuck it on my trusty sanding board with double-sided carpet tape.  The piece of mahogany is about 1/4 of an inch thick to start with.

By holding the workpiece up to the belt on the ROSS, I can get it down to the thickness I want and keep it reasonably square.

Right now the coarsest belt I have is 120 grit, so this sanding takes a bit longer than usual.

Note to self:  order more belts.

I was aiming for .090 inches thickness, and I'm within .003.  Close enough.

I probably could have gone down to .080, but the wood gets a bit fragile as it gets thinner, and I hate to start over.  I've broken these small pieces before when cutting them to shape.

The top of the guitar is about .090, so I figure the cleats will be fine - not too thick.

Now we use a razor saw to carefully cut the square cleats out.

I should probably make some kind of jig to do this, but I honestly don't do it enough.  But a jig would make the cleats a bit more precise.

Not that anyone really sees them once they go into the guitar.

Here are the cleats after the edges are beveled with a small file.

The one on the right is a tad bigger - it will go in the center where the cracks are a little further apart.

Here's how I get the cleats into place.

I have some repair magnets from Stew-Mac.  They're super strong magnets - if you get your fingers in between two of them when they are pulling together, your fingers will get pinched!  They have lots of power.

I put double-stick tape on the back of a cleat, then attach a magnet to the tape on the other side.  Then I use long tweezers which grip to the magnet.

Then we put hide glue on the surface of the cleat to be glued over the repaired area.  I glue the cleats on with their grain running opposite to the grain on the guitar (up and down in this instance) to help add strength to the repair.

The hide glue is sticky, so it wants to naturally adhere to the wood, which helps in this repair.

While I'm holding the cleat in place from the inside, I hold another magnet on the outside of the body of the guitar and whap! the magnets are drawn together.

This picture was taken after the outside magnets were attached...

...as you see here.

Stew-Mac sells these little 'handles' to attach to one of the magnets.  This makes the magnets easy to hang on to.

The magnets' pulling together acts as a clamp to hold the cleat in to place.  Super handy to have for this kind of tricky repair.

I wound up putting 3 cleats over the cracks.  The top crack is actually very tight - it didn't necessarily have to be cleated.

But I couldn't get the bottom crack fully aligned, so I went with the cleats just to make sure the whole repaired area is nice and solid.

You can also see how the cracks spread just to the original cloth lining - which helped stop the cracks from spreading when they first happened.

You can see a third crack near the bottom - it's behind the kerfing.  I was able to open it up a bit and get glue into it.  Since the lining supports it, it's a solid fix.

The guitar must have taken a fairly hard hit at some point.  But now it's good to go.

Next we'll mix up some lacquer to touch up the repairs.