Mickguard Posted July 16, 2006 Report Share Posted July 16, 2006 I started Phase II of my Rocket...stripped off the finish with acetone. Hard to believe how easy that rattle-can stuff just melts off! I'm finding it difficult to get out all of the color --I'd used black spray paint. But I'll be sanding the parts where that will show anyway. I'm getting ready to route the top and glue a new maple cap on there. My question: can I glue the cap onto the top wood as it is, that is, simply cleaned with acetone? Or do I have to remove some of the wood first? I'm leaving the neck glued in, so I don't like my chances of keeping things level. As it is, the top is still flat, and as far I can tell (pressing the cap on) it looks like I'll have a pretty good contact. The glue line might end up a little funky, but I have an idea for masking that. So will the old finish (including sealer) prevent the glue from binding --or did that get removed with the acetone? Quote Link to comment Share on other sites More sharing options...
Mattia Posted July 16, 2006 Report Share Posted July 16, 2006 Sand anything that's had finish on it before so you're sure you're down to bare wood if you want to stick anything to it with wood glue. If you use epoxy, you might be able to get away with a less perfectly cleaned surface, but I'd sand/scrape down to the wood. Quote Link to comment Share on other sites More sharing options...
Mickguard Posted July 16, 2006 Author Report Share Posted July 16, 2006 Sand anything that's had finish on it before so you're sure you're down to bare wood if you want to stick anything to it with wood glue. If you use epoxy, you might be able to get away with a less perfectly cleaned surface, but I'd sand/scrape down to the wood. Ah, given my recent troubles with trying to keep my surfaces level ( ), I wondering what the best way to go about this would be? I'm thinking I should use Setch's thicknessing jig in that case, set the bit to take off a millimeter or so? I can make a template of sorts that will let me work around the neck area (I have an extra long template bit). Edit: I just read through the Stripping section of 'Understanding Wood Finishing' --hadn't read that part before. The book doesn't deal specifically with my question -- it's only interested in refinishing the same wood, not gluing. But it seems like acetone is supposed to dissolve the finish in the pores as well? He suggests when re-staining to "Sand it lightly with 280-grit or finer sandpaper to be sure all finish has been removed." --shouldn't using a new finish present similar issues to gluing (since different types of finishes are often incompatible)? Obviously, I'm trying to avoid having to deal with having to keep things level --maybe I should look into using epoxy in that case... Quote Link to comment Share on other sites More sharing options...
j. pierce Posted July 16, 2006 Report Share Posted July 16, 2006 I have a four foot long sanding stick. (I'm guessing four feet - it's quite long, but not as tall as me. This is ballpark) It's actually a piece of extruded square aluminum channel I picked up at the scrapyard. It measures out almost perfectly square and level. I attach sandpaper with either a thin coat of spray glue, or use the self adhesive stuff. I've levelled quite a few larger surfaces with it in a rather short amount of time, which leaves a lot of scratches to take out later if I'm not gluing something on top, but works pretty well keeping the whole thing level. I usually mark the entire surface with a pencil, so I can keep track of any high spots (marks disappear early) and low spots (marks stay behind). If I keep the stick moving as I sand, (don't sand too long in one spot) and make sure that the sanding stick is always in contact with the whole body (don't slide one end off the body as I sand across, allowing for dips) and check my work as I go along (using a straightedge and checking across the body in multiple directions) I usually have no problem leveling a surface in a rather quick fashion, as long as I'm not starting with a surface that's unusually high in the middle. (bowled up) Those tend to be a little more difficult to level evenly without a little more work to keep the level surface parallel to the back. I don't know, might be easier, or worth checking out. Often times I've approached a surface with this method if I need a flat surface rather than a thicknessed one, as the setup time is less than that of the router and I can often have it done in about the same amount of time. Regardless of method, if you're sanding something and what what you sand to be flat, make sure what you're sanding with is flat, and check the work often, to identify problems early on. Quote Link to comment Share on other sites More sharing options...
Mattia Posted July 16, 2006 Report Share Posted July 16, 2006 For levelling larger flat surfaces, I've got a sheet of MDF (check for flatness, though) that's got some 80 grit (or 120 grit) glued down to it, which means unidirectional strokes with the body (move that over the grit) level things out nicely, quickly, effectively. Unidirectional strokes, even pressure, that's the key. Setch's thicknessing jig will do as well, but the MDF sheet is my 'standard' for flattening things like bookmatched figured maple tops, which, depending on figure, aren't always quite as flat as one might like... Quote Link to comment Share on other sites More sharing options...
Mickguard Posted July 16, 2006 Author Report Share Posted July 16, 2006 I usually mark the entire surface with a pencil, so I can keep track of any high spots (marks disappear early) and low spots (marks stay behind). Quote Link to comment Share on other sites More sharing options...
Mattia Posted July 16, 2006 Report Share Posted July 16, 2006 I usually mark the entire surface with a pencil, so I can keep track of any high spots (marks disappear early) and low spots (marks stay behind). Ah, another piece of the puzzle falls into place...excellent idea! For the flat piece, I could use a piece of glass, maybe epoxy a couple of handels on the back? But if I use a piece of MDF, I can shape it to the guitar...hmm... Quote Link to comment Share on other sites More sharing options...
Mickguard Posted July 17, 2006 Author Report Share Posted July 17, 2006 Uh, I use a big flat slab of MDF, kept flat. Move guitar over sanding sheet, not the other way around. And I also do the 'scribble all over with pencil' thing. I don't trust the MDF I have here, mostly because it's been subjected to too many temperature/humidity extremes. My father-in-law has a couple of slabs of marble leftover from the kitchen countertop he just had installed...unfortuneately, he refused to take the hint when I started telling him how use a thing like that would be for me On the other hand, I found a nice chunk of an old thick mirror (used to make sculptures with bits of broken mirror) that should work great as a flat surface-- with that and the pencil trick this might just work. The other thing I'm thinking might work would be to buy a good size piece of thick MDF, cut a groove in it (to accommodate the neck/fretboard, so I don't have to remove that). Then I could just run the whole top over it all at once... Quote Link to comment Share on other sites More sharing options...
brian d Posted July 17, 2006 Report Share Posted July 17, 2006 The other thing I'm thinking might work would be to buy a good size piece of thick MDF, cut a groove in it (to accommodate the neck/fretboard, so I don't have to remove that). Then I could just run the whole top over it all at once... Won't the groove introduce a non-uniform sanding....i.e. the area that passes over the groove will get sanded less and be left high compared to the rest. Brian. Quote Link to comment Share on other sites More sharing options...
Mickguard Posted July 17, 2006 Author Report Share Posted July 17, 2006 Won't the groove introduce a non-uniform sanding....i.e. the area that passes over the groove will get sanded less and be left high compared to the rest. Hmm...good point. Suppose I use relatively short strokes though--the critical parts of the guitar will always remain in contact with the sandpaper. There'll be a small stretch in the center column that will be less sanded --but most of that is already routed away (for the original pickup configuration) and the rest will be routed away for the new pickups. The most important part will be getting the outer rim level (it already is as far as I can tell). Another idea I had --suppose I take the cap I plan to use and put some sandpaper on the bottom of that--I can position it in place....use really small movements.. I'll be using 3M Frecut paper, that stuff is great ... it wouldn't take much... Or I can use the template I made for the guitar--it's pretty solid MDF. Not looking likely I'll be doing that today though...it's already past noon, we're having a heatwave, and I've been goofing off from work all morning Quote Link to comment Share on other sites More sharing options...
Mickguard Posted July 17, 2006 Author Report Share Posted July 17, 2006 Oh yeah...here's another weird question. Since the top was originally sanded WITH the grain, does it make any sense to sand it against the grain in order to level it? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.