Popular Post JayGunn Posted June 10, 2017 Popular Post Report Share Posted June 10, 2017 I'd like to make a comment about the line under your nitro on the body. I'm on builds number 2 and 3, not a very experienced luthier, but a VERY experienced furniture maker. What happens is that people use Titebond or Elmer's yellow glue or equivalent for edge gluing 90% of the time, and these glues cure by losing the water. The glue hardens in hours, but the water soaks into both pieces being glued, swelling them slightly at the joint, and wicks away in days or weeks until the moisture content at the glue line matches the rest of the plank. You can plane the wood you have glued up in a matter of hours, but the wood immediately adjacent to the glue line will shrink very slowly afterward and you'll see that slightly sunken line. What to do about it? Plan A is to let it dry for at least a week before you plane the wood. The defeats the whole purpose of using a fast drying glue. Plan B is to use a glue that does not introduce water to the joint. I use System 3 T-88 two part epoxy on anything that needs to come out beautiful, including my first bass, which was done almost entirely with epoxy. Others use West Systems epoxy, which I also might go for except that I could never finish the big containers they sell it in (for a lot of $$$) before it went bad. Don't use the 5 minute stuff--the slow drying epoxies have much higher strength. Another product with a good reputation is Smith's Oak and Teak Epoxy Glue. Epoxy likes a slightly rough surface at the joint and not huge clamping pressure, but these glues are very strong and thus very forgiving. When you figure 8-12 hour drying time, they are FAST compared to a one-hour glue that needs a weeks or more to dry out perfectly at the glue joint. I might use Titebond II for things like headstock veneer gluing where the temporary moisture increase will not cause that visible problem, but never for edge gluing on a visible surface. Why? because I have seen this same issue on table tops and been really disappointed. Another benefit is that you get at least 20-30 minutes of working time, so epoxy is great for a complex glue-up where Titebond would be setting up while you're applying the clamps. One more thing. In West System epoxy or any product where the resin and hardener are sold separately, you can save some money because the shelf life of the resin is many years. (Epoxy resin is BPA, a notorious endocrine disruptor which you can Google of course, so use gloves when you apply it). It is the hardener that ages out in a year or two and that can be replaced without throwing away the whole quart or gallon of resin. So maybe I'll try West Systems next time I run out. Last comment: you can tint epoxy (also Titebond actually) with a few drops of Transtint dye to match darker woods, like ebony, walnut bubinga, etc. Hope this helps! John 7 Quote Link to comment Share on other sites More sharing options...
10pizza Posted June 10, 2017 Report Share Posted June 10, 2017 thanks a lot @JayGunn for this information. Really helpful advice! Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 10, 2017 Report Share Posted June 10, 2017 Ahhhh....this is exactly what happened to us at work (also furniture) on something or other that I can't remember now. This was compressed fibres expanding and causing a raised line after the application of a water-based wax emulsion. Almost the same thing. I should know better. Thanks @JayGunn. That's a fantastic opening post! Quote Link to comment Share on other sites More sharing options...
Norris Posted June 13, 2017 Author Report Share Posted June 13, 2017 Great post @JayGunn The length of time it's taken to make this, I would have thought the joint would have had plenty of time to fully dry out. I'll certainly consider epoxy in future though Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 13, 2017 Report Share Posted June 13, 2017 It was probably dry a long time ago, but it's only now that the microscopic crease is showing itself. On 6/10/2017 at 6:19 PM, JayGunn said: What happens is that people use Titebond or Elmer's yellow glue or equivalent for edge gluing 90% of the time, and these glues cure by losing the water. The glue hardens in hours, but the water soaks into both pieces being glued, swelling them slightly at the joint, and wicks away in days or weeks until the moisture content at the glue line matches the rest of the plank. You can plane the wood you have glued up in a matter of hours, but the wood immediately adjacent to the glue line will shrink very slowly afterward and you'll see that slightly sunken line. Worst comes to the worst, since you're using a lacquer you can drop fill the line. The solvents in the lacquer will burn into the existing finish, so when you cut it back flat the area won't show witness lines. Double check this with your instructor. I'm sure that (s)he'll be kicking themselves when you explain JayGunn's analysis. Quote Link to comment Share on other sites More sharing options...
pan_kara Posted June 13, 2017 Report Share Posted June 13, 2017 hah I think I'm having the same thing happen to the strat that I'm building now, the primer coats used to be completely flat but now an outline of the neck section that I glued in is slowly starting to show. Probably because I've been leaving her in the sun for too long over the past week Quote Link to comment Share on other sites More sharing options...
Norris Posted June 15, 2017 Author Report Share Posted June 15, 2017 (edited) Knobs grain filled... Then dyed & starting on the sanding sealer... I also started polishing the body last night using the first 1500 grit ("rust") Micro Mesh pad. The join line has pretty much gone now. There is a tiny bit of burn through to the sanding sealer around a few of the screw holes where the lacquer seemed to cling to the edges - that won't be a problem as it'll be under the bridge. If I get any more burn through I'll have to slap another couple of coats of lacquer on, but we are ok so far. I'll see if I've got time to start on the back tonight. In other news the neck had its final coat of lacquer a day or two ago. Slowly, but still moving forwards Edited November 7, 2017 by Norris 2 Quote Link to comment Share on other sites More sharing options...
ScottR Posted June 15, 2017 Report Share Posted June 15, 2017 Nice little knob stands you've got there. SR 1 Quote Link to comment Share on other sites More sharing options...
Andyjr1515 Posted June 15, 2017 Report Share Posted June 15, 2017 There's no way of saying it without innuendo, but nice knobs, Norris 1 Quote Link to comment Share on other sites More sharing options...
ScottR Posted June 15, 2017 Report Share Posted June 15, 2017 1 hour ago, Andyjr1515 said: There's no way of saying it without innuendo, but nice knobs, Norris I'll bet that's something he doesn't hear just everyday... SR Quote Link to comment Share on other sites More sharing options...
komodo Posted June 15, 2017 Report Share Posted June 15, 2017 @JayGunn I've used West Systems for all kinds of stuff, and wonder if there's a way to tell when it goes bad? Is it usually the resin or hardener or both? I supposed I can always just dose out some and try a test piece if it hasn't been used in awhile to see what happens. Quote Link to comment Share on other sites More sharing options...
Norris Posted June 16, 2017 Author Report Share Posted June 16, 2017 13 hours ago, ScottR said: I'll bet that's something he doesn't hear just everyday... SR I keep showing Mrs Norris my shiny knobs, but she's not impressed 1 Quote Link to comment Share on other sites More sharing options...
curtisa Posted June 16, 2017 Report Share Posted June 16, 2017 Oooerrr, Mrs Slocombe! 2 Quote Link to comment Share on other sites More sharing options...
Norris Posted June 16, 2017 Author Report Share Posted June 16, 2017 2 hours ago, curtisa said: Oooerrr, Mrs Slocombe! For those not familiar with UK tv shows from the 70s, this is a reference to an innuendo-based comedy show "Are You Being Served?" However looking at the wikipedia entry, it seems that it was broadcast to the commonwealth & some former colonies Quote Link to comment Share on other sites More sharing options...
komodo Posted June 16, 2017 Report Share Posted June 16, 2017 We still refer to our cat as "pussy" purely because of Mrs Slocombe and her comedic effect. Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 16, 2017 Report Share Posted June 16, 2017 Not quite as salacious as that, however we named our most recent feline addition "Malkovich" so we can justifiably walk around saying "Malkovich? Malkovich! Malkovich Malkovich, Malkovich" Quote Link to comment Share on other sites More sharing options...
Mr Natural Posted June 19, 2017 Report Share Posted June 19, 2017 On 6/16/2017 at 4:13 AM, curtisa said: Oooerrr, Mrs Slocombe! On 6/16/2017 at 7:04 AM, Norris said: For those not familiar with UK tv shows from the 70s, this is a reference to an innuendo-based comedy show "Are You Being Served?" However looking at the wikipedia entry, it seems that it was broadcast to the commonwealth & some former colonies I laughed out loud when I read @curtisa Mrs Slocombe's comment- I had a room mate in college that was all over those old UK comedies-I immediately thought of Mrs Slocombe's "kitty cat" (so as not to sound vulgar) Quote Link to comment Share on other sites More sharing options...
Mr Natural Posted June 19, 2017 Report Share Posted June 19, 2017 and back to guitar building- your knobs are looking good @Norris. And I am man enough to say it. and regarding @JayGunn 's comment regarding water based glues- I just so happen to be watching tv late night this weekend- and on a program called "how its made" they did a segment on electric guitar- featuring Godin guitars. Interestingly they point out that a water based glue is used to glue up the body- the wood expands- and they put the blanks up for 2 months before routing the body. For what its worth- thought it was interesting- and since I mention it- here is the episode. gotta love you tube 1 Quote Link to comment Share on other sites More sharing options...
Norris Posted June 23, 2017 Author Report Share Posted June 23, 2017 Cautionary tale. If you are using Micro Mesh you should use it wet. However keep the wet away from any unsealed edges, screw holes, etc. or it will lift your lacquer! Luckily I spotted it before it became too bad and it's only affected areas that will be covered by the bridge plate. It has settled down over night and I'll leave it a few days to dry out fully. I won't be using any more Micro Mesh. It's flat enough and I'll just polish it all out now Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 23, 2017 Report Share Posted June 23, 2017 Additional recommendation on top of that, @Norris; buy some basic soap, such as the white blocks of ivory soap. No moisturisers, perfume or other crap. Basic. Adding some of that into the water for wet sanding, the reduced surface tension and lubricity of soap eliminates finish from "corning up" on your sandpaper or MicroMesh. Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 23, 2017 Report Share Posted June 23, 2017 On 6/20/2017 at 0:54 AM, Mr Natural said: and regarding @JayGunn 's comment regarding water based glues- I just so happen to be watching tv late night this weekend- and on a program called "how its made" they did a segment on electric guitar- featuring Godin guitars. Interestingly they point out that a water based glue is used to glue up the body- the wood expands- and they put the blanks up for 2 months before routing the body. I noticed that also. Two months is quite excessive, but in a manufacturing context this is simply producing bodies for stock. They can afford to build in that sort of margin for themselves. Commendable. Quote Link to comment Share on other sites More sharing options...
Norris Posted June 23, 2017 Author Report Share Posted June 23, 2017 Just now, Prostheta said: Additional recommendation on top of that, @Norris; buy some basic soap, such as the white blocks of ivory soap. No moisturisers, perfume or other crap. Basic. Adding some of that into the water for wet sanding, the reduced surface tension and lubricity of soap eliminates finish from "corning up" on your sandpaper or MicroMesh. Thanks. I didn't actually have that issue because I rinsed the pad every 30 seconds or so. They are not cheap so I want them to last. Another tip then: I used a little detergent (Ecover - we like this planet) as recommended in the instructions and it helped to reduce vacuum-based friction, as did lifting one edge of the pad very slightly 1 Quote Link to comment Share on other sites More sharing options...
ScottR Posted June 23, 2017 Report Share Posted June 23, 2017 I'm one of those non-conformists that likes to use micro-mesh dry. I can see what I've done more easily and don't have the issue of getting water into raw wood edges. I keep a stiff bristle brush upside down nearby and run the micro mesh over that every few minutes. Then wipe that on your pant legs and back to work. SR 1 Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 23, 2017 Report Share Posted June 23, 2017 Why am I not surprised. If this were a question, I would have used a question mark. 1 Quote Link to comment Share on other sites More sharing options...
ScottR Posted June 23, 2017 Report Share Posted June 23, 2017 19 minutes ago, Prostheta said: Why am I not surprised. If this were a question, I would have used a question mark. Quote Link to comment Share on other sites More sharing options...
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