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You know Mike, I don't think that every conceivable possibility was considered by Chris. I think the jig works perfectly, I had to make a couple of mods for my own designs, and I have to admit that the big Stellas left me in the same position as you. I sawed off the excess and filed it down carefully. Not a big deal...
If you making a lot of these whatever guitars, have a template made or make one yourself. It's a pretty minor problem.

Mike,
Couldn't you make your own dummy template out of some 1/4" acrylic from Lowes. Put it in in place of the original template after you have routed the dove tail. It would not have to be accurate on the shape, just accurately matching the thickness of the original template. The dove tail guide part could be a little oversize, to keep the bit away from the finished dove tail. The part south of the dove tail could be routed away far enough to get you past the end of the neck blank. Looks like the depth would match up fine, if you have the dummy template the same thickness as the original.

Very good points. Thank you both. I'll try the dummy template approach. No need to buy an expensive new template.

Well, as it turns out, lowes and other places carry .220" acrylic. The templates are .225". This means I'd cut a bit deep. I know it's not a big deal, easily adjusted perhaps a layer of tape. Just checking to see if anyone knows of 0.225" acrylic. Or a better idea. This, btw, was for creating a new template to rout off the excess. Yes, I know I could do this on the bandsaw. But I want to run this option to ground. I'm not 100% confident I won't create new issues with that approach

Mike, try usplastics.com. Also I'd recommend polycarbonate (makralon, lexan)over acrylic, it machines much better than acrylic.

_________________
Jim Watts
http://jameswattsguitars.com

For prototyping a template use plywood/hardwood run it through your thickness sander to hit your number.

Again, I was overthinking this. Thanks. Heading out to shop to build it now.

Trying to get used to the cuts. Both tear out issues confuse me. Looking into router bit, but rotates counter clockwise. I started both cuts on left. Thoughts?

Is it possible that you're taking off too much per pass?


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It's a dovetail. You only get one pass. I spoke with Andy Birko, he got me straightened out. I knew it mattered what side you started on. The neck, started on the wrong side (right side is correct). Block, started on left side, and that is the correct side, but you have to go real slow till you almost a full bit in.

This.

I do a M&T, and hit the tenon last, meaning, I work from the edges in so the "final" cut is not a "full bit" cut. It seems you're using a straight bit and finishing with the dovetail which looks good. If your tearout is not because you're taking deep cuts, I think the orientation of the scrap is a variable, particularly the body template. I dont think it'll be an issue going through the softwood top.

Btw, that is a really nice, adjustable jig you have. Maybe someday, but I'll have to live with my Robbie style for a while.

No, using a 7 degree 1/2" shank dovetail bit. The whole thing is quite stout. Template size does not permit taking limited cuts. And as far as I can tell, the intent is to do it in a single pass. I questioned this a while back in a similar thread asking if I should hog out using a straight bit, in passes, then do final cut with dovetail bit. Would love if someone has some insight here. Maybe I'll get to ask Chris when he's back in town. I'm gonna build up another surrogate and test that idea.

Have you considered roughing it out on the bandsaw and then putting it in your jig?

_________________
Jim Watts
http://jameswattsguitars.com

No, when I bought this, I was assured it was a complete system. And I believe it is. I do question the wisdom of the whole cut in one pass philosophy. Think I'm gonna order a nice 1/2" spiral bit, or better yet, check my bits, think I've got one. Tomorrow I will try light passes with straight bit and final pass with dove tail

When you said "one pass" I thought you meant the one final full depth pass required of dovetails.

There are different ways to hog out with a straight bit, easiest being a template bushing and stepping in. I'm lazy so I just use my bearing template bit, which only stays at one depth of course - I move the neck UP the jig in 2 passes (my tenons are for `ukulele necks). You'll be MUCH happier hogging out with a straight bit first (don't even have to go to final depth, leaving about 1/16" or so to cut with the dovetail bit.

Hope this helps.

Been a weekend of testing and more testing. Still got a lot of testing to do before final cuts. I tried my 1/2 spiral down cut to hog out the hole. Worked ok. I'm using a 5/8" guide per instructions. I'm thinking I should be using a smaller bit for the hogging. 3/8"? Why use such a big bit when tear out is an issue?

After talking with Chris, I have a better handle on things. I'm ordering a 3/8" spiral bit for initial clearing. Learned a whole lot about neck geometry!

Question for those who own the jig: Setting the neck angle. After dome sanding, determining the offset distance at bridge location. If the bridge is 3/8" thick, and the fretboard is 1/4" thick, do I tilt the table so that the dial indicator shows 1/8"? This assumes I have conditioned the top such that a straightedge along fretboard (no frets) touches the top of the leading edge of the bridge.