Crack or split repair and prevention

….OUCH…A guitar makers nightmare…

The Problem:

It is very sad when after all your hard work something like this happens…it shouldn’t but it does. It is surely equally upsetting for the owner. This is only the second time one of my guitars has come back looking like this but I thought I would write a few words on the subject to hopefully help prevent it happening again.

It is not uncommon among high end guitars made as they are from inherently fragile, thin plates of fine tone woods. It appears the most common place for a split to appear is along the centre seam of the soundboard between the bridge and the tail block as in the picture above. Coincidentally this can also the hardest to fix as there are more braces on the soundboard to be potentially affected.

Unless the braces have also come loose, or the top or back become separated from the sides, most splits or cracks have no noticeable effect on the tone, but it is better to repair them before they get any worse.

The Cause

All our wood is carefully conditioned before work starts but this does not make it indestructible.

Rapid changes or extremes in the environment can harm your guitar. Because the top and back are curved this allows some breathing space for the thin plates to expand and contract slightly as they take on and lose moisture, but there is a limit. Taking on moisture in a damp environment is less damaging, the plates may warp and the action may rise,  but too dry and the wood will shrink and eventually split. It can also become very brittle and even a small knock can cause it to split.

Real damage occurs invariably when guitar is allowed to dry out too much. The most common causes are:

A. left in the sun

B. hot car/van

C. attic or centrally heated room (i.e.too near a radiator)

The symptoms

You can usually spot if your guitar is drying out to much as the curved top and/or back plate will start to flatten out. This will cause the action to drop and you may experience a few buzzes or rattles while playing that weren’t there before. Other symptoms may include a dry appearance but this can be hard to spot to the untrained eye, and sharp fret ends as the fretboard shrinks and they begin to stick out slightly.

Inevitably as they are made of wood, guitars move all the time, albeit very slowly, as they react to the changes in the seasons which is why some players have their guitars set up twice a year (whether it needs it or not!). Under normal conditions most guitars don’t move enough to affect playability so the small amount of movement goes unnoticed.

The Cure

The instrument should be moved immediately to a safe environment between 45-55% humidity and allowed to settle down and stabilise. Often gaps will close up on their own but they will still need to be fixed to stop it from spreading.

Various repair techniques can be employed to cure the problem, some refinishing is normally required.

A. If the gap can be easily closed then it can be simply glued back together

B. Wider gaps must be filled with a splint made from the same material

Small cleats may be glued inside to reinforce the repair- the sound should remain unchanged if done correctly.

C. In extreme cases it may be easier to replace the damaged part altogether but this has the most potential to alter the sound of your cherished instrument especially if it is the soundboard.

Repairs like this can be tricky and very expensive so it is well worth trying to avoid them.

Prevention is much better!

Wood should not crack or split if kept at 45%-55% humidity.

Guitars are made to be played and not kept in a glass case, but if you have an expensive or cherished guitar it is well worth taking a few steps to avoid any damage caused by letting it dry out too much.

Buy a ‘hygrometer‘ (not a typo- a humidity meter), and a ‘case humidifier‘ if the room you keep the guitar is on the low side (less than 40%) and put the guitar in it’s case when you are not using it.

The Planet Waves Humidity Control Kit contains both items.

Alternatively for non techies the Planet Waves Humidipak is a two way system that gives out or takes in moisture as needed to keep your instrument in the best of health.

In future every Bailey acoustic guitar will be supplied with a Humidipak which I will also make available in my on line shop for anyone interested in protecting their own instruments.[email_link]