I decided to make a couple of ukulele necks today. Please allow me to put in a little back story here. I have been skeptical about how accurate my cut off saw is on the 90 degree setting. When I cut the joint where the neck meets the cigar box body I want the cut to be a dead ass perfect 90 and also a fair amount of neck drop. My rule of thumb is to determine how much neck drop I want, and then double it. This may seem excessive, but it works for me....so far. I found that the neck drop gets cut in half or more when the strings are installed and tightened. I blame it on the box flexing and the top dipping under the bridge. Of course that can be corrected to some extent by bracing and adding more braces here an there under the top. I prefer to keep the inside of the box free of extraneous wood when possible because it can dampen sound.
Back to the saw. I made my cut and set the neck on the box and checked the angle with my trusty, rusty square. It was off by almost 1/8" at the top. Not acceptable. I dialed in about a degree of more angle on the saw and cut again. Now the neck is leaning the other way. I decided to check my square by drawing a 90 degree line on a piece of plywood from a factory edge, then flipping the square over and drawing another line nearly on top of the first line. This showed me that my square was off. The lines were not exactly parallel.
I then got my speed square (1 piece) out of the van and checked that. It was ok. I didn't want to make any more cuts on that neck as it was already getting a little short. So I got a piece of scrap 1 X 2 , set my saw back to 90 and made the cut. I set the scrap on my level bench top and measured that with the speed square and also a drafting triangle. It was dead on perfect. Now I know my saw is good at 90 and also that I have a bad square. That square is good enough for cutting 2 X 4s for framing, but not good enough for guitar or uke necks.
Hope my story wasn't too boring. anyone else had similar experiences?
Thanks for the response. It was a good learning experience for me. I learned how to test a square on Youtube some time ago. In fact, you can actually adjust a framing square. The square I was using was a Stanley with a plastic handle. It now resides in the trash can. However, it was well used and rusty and pretty beat up. I now prefer the carpenter's speed square. A one piece design made of aluminum. The Stanley had a blade attached to the handle with 3 rivits which can loosen up over time and use. I also learned that my Ryobi compound mitre saw is accurate, at least at 90.
Also, making a test cut on a scrap could possible prevent a disaster.
Fish it back out of the trash, break off that bit of plastic, and use the steel part for a trapeze tail piece, pick guard, string anchor, mag pup trim ring, cover plate for a wiring access/hole, bridge ground, headstock decorations, fret rocker, glue it to the side of your fret saw for a depth-set, glue some sandpaper to it for a fret leveler,
other ideas folks?
Sounds like good ideas. I like the fret leveler best. Thanks for the ideas.
It also helps to check to see if your straightedge is actually straight. That could play hell with your fret jobs.
Agreed. I just use the stainless rulers. Not perfect, but adequate for the moment. I would like to have one of those StuMac fret rockers someday.
I have this number beaten into my head from molded plastic parts - 1 degree is 0.017" inch per every inch of length. It adds up quick. An 1/8" off center is probably closer to just a half a degree over a neck length. There are some good how-too's for squaring a miter saw, mine was off a bit right to left.
That is a good number to know. The real test is when you string up your instrument. The strings tell the story. From the nut, down the neck, over the sound hole, to the bridge and the termination. It all has to be perfect. Otherwise, it looks like shit.
I'm with ya except if it is very primitive then it kind of slides by. But also I realized I am usually the most critical of my projects whatever they may be. I have a couple a bit off center and worry I could make them worse if I try to tweak them, so far I have left them alone, plus it helps me remember for the next one.
Yes, and you can compensate a little by moving the bridge around, but not much. Cutting the end of the neck on a non-neck through is about the most critical cut on a CBG. I have tried many methods, including Japanese pull saw with home made mitre box, band saw, etc., etc. Finally got a decent cut off saw and then had to put a $50 blade on it (fine). That is working well now that I have thrown out the offending square and using better squares.
Square!?!?!? Wowsers... way to technical for me...
While a speed square seems to do the trick for me, I still find that if I am off the slightest bit on my cut with a hand saw, the things can be just the slightest bit out of whack.
Or maybe my head is slanted and everything I see looks crooked......