Using Plastic Tub for humidity control

[Matt_W]

Hi to everyone on the forum, its my first post back in a while.

Ive fired up the tools after about 10 years to start making a couple of Ukes. I'm prepping the parts required, back and sides, top, linings, neck blocks, tail blocks, neck blanks, fretboards etc.

I don't have any way to control humidity in the shed. I'm in the Yarra Valley and the BOM reckons its 99% RH at the moment. I would like to use a plastic tub with desiccant packs in to store the components in for a few weeks until I'm ready to start gluing cross grain braces etc. I expect they would need to be in the the tub for a bit to draw the moisture out.

The thin bits like the soundboards and back and sides I've cut up in the last week or so from drawer fronts- they are old timber reclaimed from a dresser but are quarter-sawn. They still need some thicknessing down. The thicker mahogany neck blanks I've had on the the shelf for years.

I store my 3d printer filaments in the IP67 tubs from Bunnings with two of the calcium chloride desiccant tubs in. Fit 4 rolls and two tubs and does seem to keep the filaments from becoming brittle and snapping all the time.

[url] https://www.bunnings.com.au/ezy-storage ... 204842[url]
[url] https://www.bunnings.com.au/dampfree-30 ... 480959[url]


The humidity in the tub sits around 20 - 25% RH consistently. I have a calibrated temp humidity datalogger in the tub with them. Surprisingly the desiccants are about 18 months old and still not fully expanded, i guess once they're sealed the moisture only comes in slowly.

20%RH is probably a bit too low for instrument woods, but once i take out the soundboard and plonk it on the go-bar deck, its going to start to absorb moisture and expand. How fast would this happen? I would prep and dummy fit all the braces, bridge plates etc, and leave in the tub for a week or two before gluing up. I could glue one or two braces at a time and place back into the tub, or glue up all of them at once, not sure.

Does anyone have an idea if this will turn into pringles?

[kiwigeo]

The cheapest and simplest dry box I ever saw was a cardboard box with an incandesant light bulb. Heat from the bulb was enough to keep the humidity at a reasonably low level.

The problem of course is finding an incandesant light bub these days.

[TallDad71]

As I understand it humidity itself is not an issue for building a Uke. The big problem is a change in RH from the workshop to the place of the instruments final resting place.

If you know where the Uke will eventually live, shouldn't that be your target RH level, storing parts at 25% humidity when they will be played at 60% feels like a risk to me.