Extreme dryness, humidity shifts and fingerboards

TheSuzie · #1 01-27-2011, 07:23 PM

Forgive me for mentioning an eub here but, I know you guys know your wood.

Well, I am back after another round of very rough times. A friend of mine has offered to build me an EUB as a favor and in return for past favors. Most of the instrument will likely be solid wood with a plywood topped sound chamber and will be finished in shellac. Not sure what the fingerboard will be yet though likely candidates are ebony or rosewood. It will be glued up (all hide glue) to a neck made of something like poplar or birch. Not sure what to do to treat the back of the neck since I am allergic to almost everything in creation.

The issue is that I spend a lot of time in an area where the humidity can easily get down to 5% and then pop way up when the rainy season comes. While I do use some AC to dry things out when it is very wet and to mitigate the worst of the heat, humidifiers are out of the question due to my particular health issues.

Will I have problems with an unfinished fingerboard under such conditions? How strong is the chance of cracking or maybe the board working loose from the neck (not the end of the world but a hassle if it keeps coming loose). I really can't treat the board with anything because I have not found any such thing that is safe for me to use.

Thanks,
S

chuck3 · #2 01-27-2011, 07:27 PM

I can't solve your problem but I am sympathetic. My carved-top Upton undergoes a complete personality change when the heating season starts - because of the dryness resulting from the steam heat. I have to move the bass out of the practice space into the living room - and even so, the bridge is maxed out with the adjusters in high position, otherwise the strings would just be lying on the fingerboard.

I guess my one suggestion is have a good adjustable bridge.

forester · #3 01-27-2011, 07:48 PM

lean toward the ebony...better unfinished lustre' etc.
birch neck...stable gluing platform and less allergenic than (yellow) poplar.

shouldn't have major problems if the woods are seasoned properly.

PaulCannon · #4 01-28-2011, 05:04 AM

What exactly are you allergic to? Are you allergic to mineral oil?

Have you crossed Watco oil off your list? The Watco natural is a pretty common fingerboard finish. The ingredients are "secret," but you can read about the chemical properties and health effects here.

You can also sand it into oblivion, which would make an oil finish unnecessary. If he works the fingerboard from a low grit sand paper to a very fine micro mesh, perhaps as far as 12,000 grit. This would make the fingerboard and neck extremely smooth and shiny. It's a lot of work (sanding the the neck and fingerboard through 18 grits), but some luthiers will do it for extremely fine instruments with high quality fingerboards.

kurt ratering · #5 01-28-2011, 08:15 AM

+1 on mineral oil

Jason Sypher · #6 01-28-2011, 08:30 AM

I thought there were humidifiers specifically for people with allergies etc? Aren't ultrasonic type designed to kill all bacteria and germs etc?

http://www.allergybegone.com/

TheSuzie · #7 01-28-2011, 12:12 PM

Quote:

Originally Posted by PaulCannon

What exactly are you allergic to? Are you allergic to mineral oil?

Allergic to almost everything, it seems. Mineral oil is a no go. I am sensitized to many petroleum products. Mineral oil is not the worst of them for me but it certainly is not good.

I will investigate the other options you mentioned. Thanks for the info.

As far as humidifiers. I have very severe reactions to mold. Beside that, I am staying in special housing specifically built for people with these sort of problems (very rare and hard to find), It is against the rules to have humidifiers and every effort is made to keep the place dry to prevent any possible mold issues.

Thanks again for everyone's responses,
S

powerbass · #8 01-28-2011, 01:22 PM

I would leave the neck without a finish perhaps you could use olive oil on the finger board

TheSuzie · #9 01-29-2011, 08:36 PM

Thanks for everyone's input.

I would be worried about olive oil going rancid. Will definitely try to go with ebony. Need to ask again about the neck wood.

S

PaulCannon · #10 01-30-2011, 04:58 AM

Quote:

Originally Posted by TheSuzie

Thanks for everyone's input.

I would be worried about olive oil going rancid. Will definitely try to go with ebony. Need to ask again about the neck wood.

S

Are you allergic to ebony? It's a somewhat common allergy, and if you are so sensitive that just touching it will cause problems, you may need to find an alternative.

I haven't heard of it being a problem for players, just the luthiers who have to work in ebony dust all day. Still, I thought I'd mention ebony is a known allergen.

uprightben · #11 01-30-2011, 08:16 AM

Ebony and rosewood are both pretty much toxic. When properly sanded, ebony oils pretty much stay in the board, but rosewood is very oily. The earlier suggestion to just sand the ebony to about 12,000 grit micro mesh is a good one, and need not be such a pain. If the surface is prepared with a sharp scraper first, one can start with 180 or even 220 grit paper and work one's way up from there. Ebony especially will "polish" with nothing more than fine abration.

I would also give a +1 to looking into mineral oil. It is the only food grade oil that will not go rancid and cause you a bacteria related problem.

Jason Sypher · #12 01-30-2011, 08:36 AM

I just want to say that I hope we can help you out here, your predicament is a tough one. Hang in there.

TheSuzie · #13 02-03-2011, 10:14 PM

Thanks,

I am getting kind of down about things. My level of function is pretty low.

I am just going to have to test some more wood samples and even that is no guarantee unless I am testing the exact piece of wood. This is especially true where so many various species can all be called the same common name. There are some woods I really can't even be in the same room with like pines and cedar but I don't know all of them. Some things may be OK if they are sealed but I can't deal with most finishes. I will have another talk with my luthier and try to figure out how to get this done.

Thanks Again,
S

Jake deVilliers · #14 02-04-2011, 12:14 AM

Quote:

Originally Posted by TheSuzie

Thanks,

I am getting kind of down about things. My level of function is pretty low.

I am just going to have to test some more wood samples and even that is no guarantee unless I am testing the exact piece of wood. This is especially true where so many various species can all be called the same common name. There are some woods I really can't even be in the same room with like pines and cedar but I don't know all of them. Some things may be OK if they are sealed but I can't deal with most finishes. I will have another talk with my luthier and try to figure out how to get this done.

Thanks Again,
S

You can do this Suzie! Email me if you have specific questions or not!

iiipopes · #15 02-04-2011, 12:47 AM

Do you have a hobbyist's store (furniture, custom fountain pens, etc.), or exotic woods store nearby? I'm lucky that I do, and I can go see the actual woods in person and choose characteristics. Now, I'm not allergic to anything, but my wife is hypersensitive to oak and juniper/red cedar, and guess what is very prevalent around where I live? Now, I don't want you to unduly expose yourself to a reaction or something that you feel you would need an epi pen just in case something really reacts, but a trip to a store that has the various woods in stock might work.

The unfortunate thing is that all woods can cause an allergic reaction, depending on the chemistry of the wood and the body chemistry of the person affected. There are many charts out there on the toxicity of woods, but they don't help. Here is a chart that lists woods and their known allergies, but goes a step further and lists the relative incidence of known allergic reactions. Perusing the chart for woods that "rarely" or that it is "unknown" that a reaction occured to a particular wood might be a way of starting to sort out the whole situation:

http://www.mimf.com/archives/toxic.htm

For example, purpleheart is a very hard wood, harder than maple, that makes a good fingerboard that doesn't need to be finished. According to the chart, if a person is prone to reaction, this is a wood that seems to only rarely cause a reaction.

Here is another website that describes different woods. There is a general chart that tells the expected reactivity of a person to a lot of woods, which isn't that helpful, but when you click on a particular wood, it will have a "safety" section that describes in more detail the type of known reactions and more importantly their reported incidence of occurrance, which might be more helpful:

http://www.wood-database.com/

gbaker · #16 02-04-2011, 07:16 PM

If you can tolerate it boiled linseed oil (not a petroleum product) is a good finish for bare wood. Nice to the touch. It is not long-lasting and much be reapplied (with a rag and wiped off) every few months. Note it is purchased as BOILED linseed oil.

Concerning humidity - Finish is not really a help with humidity. In instruments, woods glued together cross-grained are generally the problem areas because wood expands across the grain (direction) much more than with the grain. For example ribs (panels) are hard-glued at the end to lateral blocks (sticks). Sometimes the panel dries and contracts to the point that it cracks. However the neck and fingerboard grain run in the same direction and if the two woods are at the same humidity when they are glued, they should not be a problem. Also a plywood body will not be prone to cracking.

Hope this helps.