Back seems to have warped a bit

[mike_87]

I just noticed that the back of my Taylor has had something unpleasant happen to it. I think the wood expanded a bit causing the clear coat to crack. I'm not sure how this happened and I'm not sure what to do about it and how to prevent any further damage. Only a small section of the guitar is affected, the rest is all normal.

I'm in Toronto, we're in winter, the heaters are on. I keep this guitar on a stand all the time, when I'm not using it I keep a damp sponge inside the sound hole. It's the same thing I did last winter and this is the first time anything like this happened.

This is the best picture I could get. I wish I could get a better pic because there is a lot of important detail not shown.

That white stuff is clear coat.

Any advice/guidance is appreciated.

[Sam VanLaningham]

Hi - by chance, is the stand on the floor? Do you have wood floors?

Im sure things are a bit different up here but when its really cold here Ive measured a >20°F gradient from floor to 6 feet off the ground. The temp on the floor was 55°F (13°C) and the around my head it was 75°F (~24°C). This also leads to a big gradient in relative humidity.

I was keeping an Eastman OM with rosewood back and sides on a stand on the floor and the bottom of the back (about same position as yours) warped.

I assumed that the gradient from the guitar lower bout to headstock was causing the problem.

[mike_87]

Yes I am keeping in on a stand on a wood floor...that's weird.

So what's the solution, keep it lying flat?

[gitnoob]

Looks like a (lack of) humidity issue to me. You may need more than a sponge. Check it for other signs of drying out -- the top will start to flatten or sink, and the back will flatten.

[mike_87]

Yes that makes a lot of sense.

Should I keep my guitars in their cases when not in use?

[gitnoob]

Step 1: get a hygrometer
Step 2: get a humidifier

I leave mine out of the case, but only with a room humidifier keeping things at around 40% RH.

[mike_87]

I read that cheap hygrometers are extremely inaccurate. Anything under a few hundred dollars is not worth using. Is there any validity to this?

[gitnoob]

When the humidity is as low as yours probably is, you don't need to be too concerned about accuracy.

I use this:
http://www.amazon.com/Ambient-Weathe...ote+hygrometer

I monitor the humidity in different areas of the house with the 3 sensors. You can calibrate them if you want to, but I find them accurate enough out of the box.

[charles Tauber]

Originally Posted by mike_87

I read that cheap hygrometers are extremely inaccurate. Anything under a few hundred dollars is not worth using. Is there any validity to this?

Greetings from Brampton, where the weather is the same.

No validity whatsoever. You aren't Environment Canada. A $10 hygrometer will tell you what you need to know with sufficient accuracy. Is your humidity around 20%, 45% or 80%?

When you go to the store to buy one - Canadian Tire, Home Depot, Home Hardware... - look at several and compare their current reading. Buy one that agrees with several others. (That doesn't guarantee accuracy, but eliminates outliers.) You don't need a multi-zone, electronic unit. As far as your guitar is concerned, the only place that the humidity matters is where your guitar is actually stored - not outside, not in the next room, not at the ceiling. A simple mechanical device is sufficient. If you want fancier, go for it, but it isn't necessary.

Based upon the heating system and environment you have, you decide which method of humidification is best. You can keep your guitar in a case and humidify only the interior of the case - a very small area. You can humidify only the room in which the guitar is stored - a small area. Or you can humidify your entire dwelling, a larger area.

[Ned Milburn]

Originally Posted by mike_87

I just noticed that the back of my Taylor has had something unpleasant happen to it. I think the wood expanded a bit causing the clear coat to crack. I'm not sure how this happened and I'm not sure what to do about it and how to prevent any further damage. Only a small section of the guitar is affected, the rest is all normal.

I'm in Toronto, we're in winter, the heaters are on. I keep this guitar on a stand all the time, when I'm not using it I keep a damp sponge inside the sound hole. It's the same thing I did last winter and this is the first time anything like this happened.

Any advice/guidance is appreciated.

I remember that Toronto winters can be quite dry. If you leave the instrument on a stand, I recommend the sound hole cover humidifiers that prevent humidity added from escaping through the soundhole.

The instrument crack itself doesn't look serious at this point. It may still be so tight that it won't even wick any glue. If you are concerned, you can get some titebond 2 and water it down slightly, then massage this into the crack. If there is any movement in the crack, you can often see either (or both) air bubble through the glue, or after that, you can actually see the glue suck into and squeeze out of the crack. From your photo, however, I can't imagine that there will be much wicking, nore will there be movement. If you try this, excess glue can be wiped off easily with a tissue or cotton ball. You can use a slightly dampened cotton ball to easily wipe clean any dried glue residue.

I'd recommend, however, that you just continue to humidify well, and keep your eye on that area (and the whole back and guitar for that matter) to make sure the present issue doesn't worsen, and that you don't see any new developing cracks. Just like medicine, it's best to get the cracks in their initial stages, then they can often be locked in place by a skillful gluing operation before any warping may begin. If it worsens, then post again or visit a local skilled craftsman (of whom I know there are several in the GTA).

Cheers.

[WaddyT]

Unless you have a room humidifier or a whole house humidifier, do not leave your guitar on a stand in winter months. I fight to keep my shop humidified to 42 - 45% in the winter even in North Carolina. If the humidifiers run out of water at night, it will be close to 20% on a very cold night in the shop. I try not to let that happen, but it occasionally does, though it wouldn't be for more than a couple of hours as I fill the humidifiers (note the "s") every night before going to bed. Get a sound hole humidifier and or a case humidifier and put the guitar in the case. Take it out when you play it. I know, "It's not cool!" but it might save your guitar. If you are seeing warping, put the guitar on the stand, get a sponge and wet it, set it in a dish on the floor under the guitar, and put a big plastic bag over them. Leave it there for a couple of days, then put the guitar in a case with a humidifier.

[1OUfan]

Is this damage at the butt-end of the instrument? You stated that you keep a damps sponge inside the instrument during the winter---do you keep the sponge in a baggie with holes punched in it or just the damp sponge by itself. I ask, because the wood and binding at the separation appears swollen to me. If the sponge was not in a baggie and was a bit too damp, it could have fallen to the bottom of the guitar and wicked moisture in to the area where the damage is. This wicking would soak in to the wood and swell it, causing the separation. Just a thought.

[mike_87]

1OU - the sponge is in a ziploc, and it's rung out so there's no drips. That would be pretty funny if I put a wet sponge straight in the guitar.

Anyway, so I'm keeping the guitars in their cases when not in use from now on until the heat is off. I'm also going to pick up the Oasis humidifiers for my acoustics. I think we should be good after that.

I bet you whoever said it was right, the moisture was escaping from the sound hole. Must keep it enclosed.

Thanks for the replies guys. I just picked up a Gibson LG-1, I'll be making a thread soon dedicated to dealing with the slight bellying that's happening there. Should be good.

[SGF_MO]

Hi Folks,
First post ever and although an avid player and collector, I’m kinda new at the Luthier thing. Here is a helpful link I found re: warpege, straitening, storage, and re-acclimation. I’m having a similar problem with two sets of cocabola backs and sides.

http://tonewood.com/luthier-resources/care-of-wood.html

Sometimes based on the crack size you can go small 000 or 0M size and bypass the crack. Either way, after straitening cracks can be dealt with prior to building. Sorry the pictures being referred to are not displaying. I hope to be a giver and receiver on AGF.

God Bless,
Sean

[jim1960]

Originally Posted by SGF_MO

Hi Folks,
First post ever and although an avid player and collector...

The thread you responded to is 6 years old. I'm betting the issue has been resolved by now.