GoodWood Posted July 31, 2007 Report Share Posted July 31, 2007 I 'sealed' my top and it started to curve extreem when I removed it from the plastic. storage bag- I turned it over and did some steaming/ water and it curved the opposite way, just about gave up, but I turned it top up and it curved back, but way too much.. I dont mind a little curve in it,to match the dish a bit, but this has about 1 inch depth to it, like this ) instead of this l I sanded most of the shelak off the top, but it wont go 'flat'. How do I get it back to flat naturally? Sand it all down to bare wood? Quote Link to comment Share on other sites More sharing options...
Jon Posted July 31, 2007 Report Share Posted July 31, 2007 Was this piece fresh out of the package, or has only been in your area / house for a short while? Quote Link to comment Share on other sites More sharing options...
verhoevenc Posted July 31, 2007 Report Share Posted July 31, 2007 Yeah, sounds like you were using lumber that wasn't dried yet... that or you've moved it from an area of high humidity to low, or vice versa. Chris Quote Link to comment Share on other sites More sharing options...
Daniel Sorbera Posted July 31, 2007 Report Share Posted July 31, 2007 Why was it in a bag? Do you mean a bag they put it in while it was shipped and you just got it? When you receive lumber you should set it so there is air on both sides and forget it for around a month (if it was previously dried). This way it will get acclimated to your climate and you wont have any problems with it warping. Quote Link to comment Share on other sites More sharing options...
GoodWood Posted July 31, 2007 Author Report Share Posted July 31, 2007 Why was it in a bag? Do you mean a bag they put it in while it was shipped and you just got it? When you receive lumber you should set it so there is air on both sides and forget it for around a month (if it was previously dried). This way it will get acclimated to your climate and you wont have any problems with it warping. No this top was glued up in November. I keep all my back/ top woods in a plastic bag. Top sealing it with Shelak and leaving it in the open warped it. Anytime I leave it out any top it will warp to some degree. That is just normal. The shelak seems to keep it from warping back now. Humidity is around 45%. Im in a dry area. Quote Link to comment Share on other sites More sharing options...
Mattia Posted July 31, 2007 Report Share Posted July 31, 2007 Really, no reason at all to store wood in plastic bags. Not unless you want to risk mold if there's a tiny amount of water in there and temp starts shifting enough to let it condense. It's a relatively effective way of drying wood quickly ('garbage bag kiln', put in black garbage bag, put in sun for a while, let sweat, remove wood, turn bag inside out (get water away), repeat...). Glued up (non-braced!) tops and backs I just leave lying around, propped against something so there's airflow around them, or simply stacked and/or stickered. You want them to get their movement out, after all, and you really want to know if they're in the mood for shifting about! Braced tops are a different issue, because you've added cross-grain glued strips of wood. And yes, leave all the wood bare. You can seal the ends of a piece of wood, but not all faces. Not unless it's a green burl and you're a woodturner or something. If you don't want it to move, sticker and weight it. A lot of wood, particularly thin stuff, will warp a little when it arrives somewhere, but just left alone for a while, it usually re-acclimatizes and settles down. This has nothing to do with whether it's dried properly or not, and everything to do with temp and humidity shifts. If this wood's been in a bag since November, it's been living in its own little microclimate. Quote Link to comment Share on other sites More sharing options...
fryovanni Posted July 31, 2007 Report Share Posted July 31, 2007 Yes, what Mattia said. Don't close your soundboards up in a sealed bag, it does nothing to protect the wood. It actually invites problems. Peace,Rich Quote Link to comment Share on other sites More sharing options...
GoodWood Posted August 2, 2007 Author Report Share Posted August 2, 2007 (edited) oK, I am surrendering this top (for future backsplice?) It was a cheapie $15.00 deal and it surved its purpose, I guess, The soundhole was cut too large It was the wrong direction/ crappy grain ended up in lower bout area I thinned it too thin? (003-005) Well, it could have been a light string guitar the warping is too difficult to control at this point its all over the place. Crack in top (This would have repaired just fine, Cracks need "stopholes" drilled in front of them, and it worked fine.) The top flexes pretty good, I guess, I think it would be fine but for the warping and soundhole issue which would be a pain to fix anyway. SO Ive lost a set of sides, and a top now (from the 'backup pile") Although the sides will be used for side crack strips and this top can be economicly used for backsplice. Lessons learned, no shelak topcoat for sealing (Kinkeads book), at least not as thick as I apparently put it on. I did it because the black stuff from scraping the rosette was getting into the unsealed wood, so I may do a super light seal on the upper bout only, around the sound hole area, but I may just use the drillpress to sand this stuff out in the future. I planned ahead by getting 2 of most everything for backup, didnt expect to need to USE it all up! So far, everything is a disaster! Edited August 2, 2007 by GoodWood Quote Link to comment Share on other sites More sharing options...
fryovanni Posted August 2, 2007 Report Share Posted August 2, 2007 oK, I am surrendering this top (for future backsplice?) It was a cheapie $15.00 deal and it surved its purpose, I guess, The soundhole was cut too large It was the wrong direction/ crappy grain ended up in lower bout area I thinned it too thin? (003-005) Well, it could have been a light string guitar the warping is too difficult to control at this point its all over the place. Crack in top (This would have repaired just fine, Cracks need "stopholes" drilled in front of them, and it worked fine.) The top flexes pretty good, I guess, I think it would be fine but for the warping and soundhole issue which would be a pain to fix anyway. SO Ive lost a set of sides, and a top now (from the 'backup pile") Although the sides will be used for side crack strips and this top can be economicly used for backsplice. Lessons learned, no shelak topcoat for sealing (Kinkeads book), at least not as thick as I apparently put it on. I did it because the black stuff from scraping the rosette was getting into the unsealed wood, so I may do a super light seal on the upper bout only, around the sound hole area, but I may just use the drillpress to sand this stuff out in the future. I planned ahead by getting 2 of most everything for backup, didnt expect to need to USE it all up! So far, everything is a disaster! I use shellac as a light sealer coat after I route for the rosette, and around the binding and or purfling channels. That is a good practice. I took from your posting that you had sealed the entire soundboard with shellac. Good soundboards certainly don't need to be expensive ones. Be sure though that whoever you are buying them from knows what they are doing. You do want pretty well quartered, you want minimal runnout(face grain), and as long as they use split wood they will know how to cut to minimise that, and you want reasonably straight grain, hopefully very little compression. These are all the Basics that make a soundboard at least A to AA(A grade is very low dollar$5-10, AA is generally in the $15-30 range). A little irrecgular spacing on the growth rings, maybe some color, or less than super high ring counts are what bring these sets down from higher grades AAA to master. 2A soundboards are usually quite awsome soundboards if the person cutting knows their stuff. Keep on plugging away. All these little mishaps(and they happen to every last one of us) are teaching you a ton, and you will be rolling along in no time. Peace,Rich Quote Link to comment Share on other sites More sharing options...
erikbojerik Posted August 3, 2007 Report Share Posted August 3, 2007 This will also happen if you leave the board so that one side is facing the sun though a window. Happened to my EIR back...after it was braced (concave along its length). I flipped it around and it went back to normal, then I left in the shade after that. Quote Link to comment Share on other sites More sharing options...
fryovanni Posted August 3, 2007 Report Share Posted August 3, 2007 This will also happen if you leave the board so that one side is facing the sun though a window. Happened to my EIR back...after it was braced (concave along its length). I flipped it around and it went back to normal, then I left in the shade after that. Your absolutely right. It is a bit of overdrying on the side that gets heated up. If left alone and air is aloud to get around all sides it will go right back where it is supposed to be. One thing that some do(including myself). Is to actually cook soundboards for a period of time at a moderately higher than normal temperature to over dry them. The wood will gain moisture and get back to equalibrium after it is exposed to normal conditions. Two thoughts on possible benifits. One it takes the wood through a catastofic overdried ondition that would normally cause damage on a finished instrument(such as leaving the instrument in a car on a hot day). The theory being the soundboard is less like ly to split if it has been through this condition before. Another theory, after wood has been dried to a certain level it never has the same ability to carry moisture(closes the structure to a degree, and forces out some cell locked moisture). Some also believe it cooks the pitch(???IMO???, but maybe). I am sure that this process will case harden a soundboard, but because it is so thin and you are taking it to zero effectively it does not seem to be a bad thing. I have yet to have ill effects from doing this, and it does seem to make the wood slightly stiffer and slightly more resonant(although a tiny decrease in moisture would give you these effects so that would seem to make sense). The difference is not drastic, and don't tap or flex the wood right after it is done cooking, it will sound amazing at that point but it will not stay that dry for long(it will equalize in a short period of time). Peace,Rich Quote Link to comment Share on other sites More sharing options...
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