adrock1740 Posted January 5, 2011 Report Share Posted January 5, 2011 hey everyone. haven't been on here in quite a long time. I started this build years ago, and I'm finally getting around to wrapping it up. I have some questions on finishing it though. and yes I've searched and done research. just getting as many opinions as I can so it's a neck through, black limba for the wings. the neck is a five piece laminate. wenge in the middle, cocobolo on either side that, then white limba on the outside. I'm looking for a very thin, open grained, oil type finish. I've never used tru oil, but from my experiences with other wipe on oil finishes, I was thinking about 4-6 coats of tru oil. pretty thin and open. I'm only thinking about using tru oil because it seems to be highly regarded, easy to buy, and easily repaired. I'm open to any other suggestions. my worry is the finish on the cocobolo. I was thinking of taping off the center (wenge, cocobolo), and finshing around that area. maybe get one or two coats on the center stripe after wiping it down with some alcohol. I'm worried about the red oil from the cocobolo staining my limba when I go to wipe it down though. I've also read about shellac to seal it first, than tru oil over it. just looking for everyones opinion about what might be the best way to finish my baby. Quote Link to comment Share on other sites More sharing options...
adrock1740 Posted January 5, 2011 Author Report Share Posted January 5, 2011 well from my understandings, putting a finish over cocobolo is never very certain. and also from what i understand, cocobolo and wenge are very stable woods even when uncoated. so my thought was just to get some protection and seal off the limba with 4-6 coats, leaving the cocobolo and wenge "raw'. i'd still probably go over them on the last coat or two, just so everything blends nicely. but there wouldn't be 6 coats trying to dry over the super oily coco... Quote Link to comment Share on other sites More sharing options...
guitar2005 Posted January 5, 2011 Report Share Posted January 5, 2011 Use a sanding sealer on the entire guitar first, then finish with your favorite top coat. I use Bullseye Zinnser Sealcoat sander sealer. Quote Link to comment Share on other sites More sharing options...
Linny Posted January 5, 2011 Report Share Posted January 5, 2011 Clean the Cocobolo with acetone to remove some of the natural oils and then finish as normal. A couple of coats of that zinnser stuff would be a good idea. Quote Link to comment Share on other sites More sharing options...
adrock1740 Posted January 5, 2011 Author Report Share Posted January 5, 2011 so from what i have gathered from research and here, is that i need a good barrier/sealer between the coco and my top coat. i'd like to use tru oil, what are some good barriers/sealers to go under the tru oil? should i use the shellac method i mentioned earlier, or go for a dedicated sealer? and thanks again for the help guys, really appreciate it Quote Link to comment Share on other sites More sharing options...
Quarter Posted January 5, 2011 Report Share Posted January 5, 2011 Tru Oil strait over cocobolo can be a problem. I'd not recommend wiping with acetone either as the oils will dissolve and it will get into the lighter colored wood. If it were me, I'd prep with a cabinet scraper to pull the top oily and oxidized layer off then shoot a wash / sealer coat of shellac over the whole guitar. A shellac barrier coat will seal the coco oils and leave you a compatible surface to work with. Quote Link to comment Share on other sites More sharing options...
ihocky2 Posted January 5, 2011 Report Share Posted January 5, 2011 I would go with what Quarter recomends. Oily woods can cause havoc with any oil finish. the oil in the wood is a non curing oil that will mix with the curing oils used for finishing and will cause the oil finish to never fully cure. This does not always happen, but it is not a fun gamble. The alcohol or acetone trick works well for gluing or rapidly curing finishes since they penetrate and harden before the oil has a chance to work it's way back into the wood. But some wood workers feel that technique can cause other problems, thinking that the lack of oil causes oil inside the wood to rush to the bare area and flood it with oil. If this is true or not I am not certain, but either way the area will have oil creep back into it before and oil finish fully cures and could cause issues. Shellac is a great barrier coat, and if you are already using shellac why not use it as your finish. It is the easiest finish to repair and even easier and cheaper to buy then Tru-Oil. Quote Link to comment Share on other sites More sharing options...
adrock1740 Posted January 6, 2011 Author Report Share Posted January 6, 2011 I would go with what Quarter recomends. Oily woods can cause havoc with any oil finish. the oil in the wood is a non curing oil that will mix with the curing oils used for finishing and will cause the oil finish to never fully cure. This does not always happen, but it is not a fun gamble. The alcohol or acetone trick works well for gluing or rapidly curing finishes since they penetrate and harden before the oil has a chance to work it's way back into the wood. But some wood workers feel that technique can cause other problems, thinking that the lack of oil causes oil inside the wood to rush to the bare area and flood it with oil. If this is true or not I am not certain, but either way the area will have oil creep back into it before and oil finish fully cures and could cause issues. Shellac is a great barrier coat, and if you are already using shellac why not use it as your finish. It is the easiest finish to repair and even easier and cheaper to buy then Tru-Oil. which is gonna dry faster, just out of curiosity. the tru oil, or the zinnser sealer? this is pretty much where i'm heading honestly. i was thinking a coat of zinnser bullseye sealer (which is basically shellac from what i've read), than a few coats of tru oil and be done with it. i've also read some about thinning the tru oil a bit so it dries faster, and using that as the sealer, just making sure to let the finish dry overnight before the next coat. i honestly haven't thought about using shellac as my main finish. i've honestly never used shellac before. i have used numerous wipe on oils though (tung, wipe on poly, etc) with great success. and for the type of finish i want (satin, thin, easily repairable), i was thinking oil would be the easiest way to go. i've always thought of shellac as a spray finish, but i guess it could be wiped on... Quote Link to comment Share on other sites More sharing options...
guitar2005 Posted January 6, 2011 Report Share Posted January 6, 2011 i honestly haven't thought about using shellac as my main finish. i've honestly never used shellac before. i have used numerous wipe on oils though (tung, wipe on poly, etc) with great success. and for the type of finish i want (satin, thin, easily repairable), i was thinking oil would be the easiest way to go. i've always thought of shellac as a spray finish, but i guess it could be wiped on... Don't use the Zinnser Bullseye shellac sanding sealer as a finish on a guitar unless you want the finish to be very thin. When you apply it in multiple coats, the successive coats make the finish soft. Quote Link to comment Share on other sites More sharing options...
avengers63 Posted January 6, 2011 Report Share Posted January 6, 2011 I had some problems with cocobolo once before. I emailed Marc Spagnolo for some info on the subject, as well as a couple dozen other websites. The response was unanimous: cocobolo is a real PIA to work with, and it HAS to be sealed or 1) a barrier finish will not cure, and 2) the color will eventually darken as the natural oils semi-dry on the surface. The best sealer to use is shellac. It will keep those oils INSIDE, where they belong. Shellac also has the unique property of being able to stick to any other barrier finish out there. This makes it VERY useful as a selaer. It's also a fine finish in it's own right,but it isn't used as one very often anymore. I agree that if you're sealing the coco, you should really just seal the whole thing. This would completely eliminate any possibility of some unknown weirdness later. I feel it's best to have a uniform base to work from. Shellac isn't the fastest curing finish in the world when the layers are built up, but it's pretty fast when only one coat is applied. You can handle the item in just a few hours. How should you clean off the oils before using the shellac? I used alcohol after I sanded off the top gunk, then applied the shellac immediately. Alcohol is shellac's solvent, so there was no need to make sure it was dry first. I came back the next day and used an aerosol polyurethane over the top. The color has remained exactly like it was for 2 years now. Quote Link to comment Share on other sites More sharing options...
Quarter Posted January 6, 2011 Report Share Posted January 6, 2011 ... Shellac isn't the fastest curing finish in the world when the layers are built up, but it's pretty fast when only one coat is applied. You can handle the item in just a few hours.... The very best shellac to use is mixed fresh from flake. It will dry much faster than any over the counter canned stuff, including SealCoat which is the best ready mixed out there. Shellac.net is a good vendor for flake and button and they carry a good variety of colors too. If your going to use any other top coat other than more shellac, get the dewaxed variety. Quote Link to comment Share on other sites More sharing options...
westhemann Posted January 6, 2011 Report Share Posted January 6, 2011 Yeah,fresh mixed dries pretty dang fast...as a matter of fact,if you try to go over an area 30 seconds after you wiped it on,your rag will stick and make a mess. Quote Link to comment Share on other sites More sharing options...
adrock1740 Posted January 6, 2011 Author Report Share Posted January 6, 2011 Just yesterday someone posted a write up tutorial on French polishing (shellac) on another forum.... it's cool, i'm going for a very thing finish so... Don't use the Zinnser Bullseye shellac sanding sealer as a finish on a guitar unless you want the finish to be very thin. When you apply it in multiple coats, the successive coats make the finish soft. it's going to be very thin, maybe 6-8 coats total. I had some problems with cocobolo once before. I emailed Marc Spagnolo for some info on the subject, as well as a couple dozen other websites. The response was unanimous: cocobolo is a real PIA to work with, and it HAS to be sealed or 1) a barrier finish will not cure, and 2) the color will eventually darken as the natural oils semi-dry on the surface. The best sealer to use is shellac. It will keep those oils INSIDE, where they belong. Shellac also has the unique property of being able to stick to any other barrier finish out there. This makes it VERY useful as a selaer. It's also a fine finish in it's own right,but it isn't used as one very often anymore. I agree that if you're sealing the coco, you should really just seal the whole thing. This would completely eliminate any possibility of some unknown weirdness later. I feel it's best to have a uniform base to work from. Shellac isn't the fastest curing finish in the world when the layers are built up, but it's pretty fast when only one coat is applied. You can handle the item in just a few hours. How should you clean off the oils before using the shellac? I used alcohol after I sanded off the top gunk, then applied the shellac immediately. Alcohol is shellac's solvent, so there was no need to make sure it was dry first. I came back the next day and used an aerosol polyurethane over the top. The color has remained exactly like it was for 2 years now. thank you very much for this post, lots of useful info. i'm definitely just gonna seal the whole thing if i'm sealing the coco. so i'm thinking my plan will stay the same. one or two "thin" coats of shellac, than 4 or so of tru oil and leave it at that. i guess i should get some flakes to make my shellac? i've heard that zinnser sealer coat is pretty good stuff for over the counter, and i'm just using it for a sealer... Quote Link to comment Share on other sites More sharing options...
avengers63 Posted January 7, 2011 Report Share Posted January 7, 2011 I've always used the canned stuff from the store without issue, but mixing your own would be a LOT better. Shellac has an expiration date. The older it gets, the darker it gets. On a finishing note, I've put a few coats of shellac on stuff and then buffed it with steel wool. So long as you keep the coats to a minimum - say 2-4 - you'll get a matte finish and still be able to feel the wood texture. It won't be in any ways durable, but it should offer a reasonable amount of protection from moisture. Quote Link to comment Share on other sites More sharing options...
adrock1740 Posted January 7, 2011 Author Report Share Posted January 7, 2011 I've always used the canned stuff from the store without issue, but mixing your own would be a LOT better. Shellac has an expiration date. The older it gets, the darker it gets. On a finishing note, I've put a few coats of shellac on stuff and then buffed it with steel wool. So long as you keep the coats to a minimum - say 2-4 - you'll get a matte finish and still be able to feel the wood texture. It won't be in any ways durable, but it should offer a reasonable amount of protection from moisture. i have no problem mixing my own, i just need to find some locally, without having to buy a whole pound. why couldn't i apply more coats, and just buff it with the steel wool or pad to get the same matte effect? i don't want more than 6-8 coats though, just depends on how it goes on, 4 might be enough. i'm going to give it ample time in between coats in any case, at least overnight, just to make sure everything is cured before applying the next coat. i'm gonna get some shellac and some coco tomorrow to do some samples. Quote Link to comment Share on other sites More sharing options...
avengers63 Posted January 7, 2011 Report Share Posted January 7, 2011 You can apply as many coats as you want. It'll just take longer to cure. But I thought you wanted to still feel the wood? Quote Link to comment Share on other sites More sharing options...
Quarter Posted January 7, 2011 Report Share Posted January 7, 2011 i have no problem mixing my own, i just need to find some locally, without having to buy a whole pound. If you have a Rockler or Woodcraft store local they will have some flake. For a full on shellac finish, French polishing is the old school way to lay it down. Here is about the best French polishing guide around and even if you don't do a French polish, it has a lot of good information worth checking out. http://www.milburnguitars.com/fpbannerframes.html Quote Link to comment Share on other sites More sharing options...
adrock1740 Posted January 7, 2011 Author Report Share Posted January 7, 2011 You can apply as many coats as you want. It'll just take longer to cure. But I thought you wanted to still feel the wood? i definitely do. i'm just not familiar with the coverage, or thickness, of shellac. 4 coats might be plenty. but i've been thinking about doing a 1 pound cut so it's thinner, and dries a bit faster. so the coats might be a little thinner than "average". i'm having a pretty tough time deciding between three finish options. 1. all shellac finish 2. sealed with shellac and tru oil for the top coat 3. all tru oil, with a quick drying thinned down "seal coat". still have to test this to see how it'll work with the coco... i don't know why i'm stuck on tru oil so much. i've never used it. it's just that i've heard such great things about it. and it seams a lot like wipe on poly, or tung oil, which both are super easy to use. and seamed to dry pretty quick. i don't really feel like mixing shellac and "learning" how to use it, but if it's what needs to be done then thats that. maybe shellac dries faster than what i'm used to... i might have to bite the bullet and buy both and do some test with to see which i like better. didn't want to spend the money, or time, but i think that's what's going to have to be done If you have a Rockler or Woodcraft store local they will have some flake. For a full on shellac finish, French polishing is the old school way to lay it down. Here is about the best French polishing guide around and even if you don't do a French polish, it has a lot of good information worth checking out. http://www.milburnguitars.com/fpbannerframes.html we have a woodcraft here in Austin. i'm heading there today to buy some stuff and thanks for the link, definitely gonna check it out Quote Link to comment Share on other sites More sharing options...
Quarter Posted January 7, 2011 Report Share Posted January 7, 2011 (edited) I'm a big fan of shellac and Tru Oil too. Shellac is one of the very best sealers out there and is compatible with a huge variety of finishes. Besides using as a sealer, I like it for adding a nice and natural amber color to maple and it can warm up other woods too. Below is some Kush orange flake on some curly maple topped with Tru Oil. . Edited January 7, 2011 by Quarter Quote Link to comment Share on other sites More sharing options...
adrock1740 Posted January 10, 2011 Author Report Share Posted January 10, 2011 that looks beautiful quarter!! so i bought some scrap cocobolo, a quart of zinnser seal coat, and a bottle of tru oil yesterday. i'm running four tests right now. 1 - all tru oil, wiped with alcohol. 2 - all tru oil, not wiped with alcohol (just to see what happens). 3 - two seal coats with tru oil on top, wiped with alcohol. 4 - two seal coats with tru oil on top, not wiped with alcohol (just to see). i started tests one and two last night before bed, both of which are still slightly tacky. i started tests three and four about 15 minutes ago, both of which are already dry to the touch. i think i know where this is going to go... Quote Link to comment Share on other sites More sharing options...
madhattr88 Posted February 1, 2011 Report Share Posted February 1, 2011 I've used Birchwood Casey filler/sealer like u are using shellac now. Then applied 10 coats of tru-oil I'm anxious to see your results, because I heard the shellac is better. Any pics? ps. I used acetone to remove oils from a very oily rosewood headplate. Nothing would cure over it until I wiped it down. Quote Link to comment Share on other sites More sharing options...
adrock1740 Posted February 9, 2011 Author Report Share Posted February 9, 2011 sorry about the lack of updates guys. got busy finishing this guitar, and side tracked by life. i forgot to check back here when i was done but i'm gonna try to be more active here, as i have more builds coming up in the near future. and here is the finished guitar - http://projectguitar.ibforums.com/index.php?showtopic=44752 Quote Link to comment Share on other sites More sharing options...
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