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Hesh, I glue mine first then profile.... that way the blocks will match the top and back radius perfectly.
I profile the back part of the sides prior to bending but keep the top completely flat until the blocks are in and the kerf in on! Bowl sand after that...

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

I profile roughly first, then glue the end blocks. I make them slightly oversize then sand to the proper contour. After the box is closed I rout for the tennon, and drill for the neck bolts.

Al

Same as Peter, absolutely, glue then profile. Remembering to make the blocks tall enough so that they have the necessary depth at their high point. First time I made one with a Spanish heel and a top extension I forgot that it would be higher further in and made them the height of the ends. I ended up having to make the whole guitar 5mm shallower! Profile the back edge before bending, glue in the blocks, profile the top edge with the flexible template, glue in the linings then bowl sand. The sanding is mainly to get the blocks and linings profiled the initial side profiling should take care of the side wood..

ColinColin S39075.7449305556

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I profile the sides then set in the blocks and kerfing , then the I set the kerfing and blocks to the sides and true them to the side.
this saves time and you can get the kerfing pretty close to the set and justneed a light clean off.
   The neck and tail blocks are trimmed before gluing and they get trued with the last set up from the luther disk. this assures the widest glue surface off the kerfing I can get

John:

I profiled the rims in the mold before attaching the kerfing, and boy did it save a lot of time. I have templates to get it close, but still needs some tuning. Another thing I did once I got the kerfing on while profiling was to set my 25 pound bag of lead shot on top of the sanding dish. I'll bet it cut my sanding time by at least half. Profiling is one of the jobs that I enjoy least, but the lead shot really helped. I have the shot bag around for fretting and other jobs, so I have found yet another use for it.
Merry Christmas to all! tom harbin
PS: John: I got the mold, thanks.

Hesh...I basically agree with John, Colin and others on the steps to profiling the neck block and the order in which they do it. I also drill the holes after profiling. The problem with using a pre-drilled block (as you have discovered) is getting the holes to align with a pre-fab neck. If you only sand a "little" then you don't have the proper angle on the top of the neck block and that results in a reduced and/or improperly angled gluing surface. I always sand until the entire top of the block has been jointed...that way the FB extension will lay flat and have the proper projection toward the bridge. The best solution, IMO, is to install undrilled neck blocks and do the drilling after profiling.

Your other question about bending profiled sides. Here's what I do.

1) I have a masonite side profile template for each model. I draw out that profile and cut it close to the line.
2) Draw a line on the profiled side where the waist is to be located on the bender.
3) Wrap the side in whatever, spritz and make a mark on the wrapper on the STRAIGHT side.
4) Align that mark at the waist mark on the bender. This requires that you move the side to one side of the bender to have the straight edge aligned. The oppoeite side will align with the ooposite side of the bender.

Doing it this way keeps the side profiles straight and square to the top side. Sanding is pretty straightforward after that.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Hesh I certainly wouldn't profile both edges prior to bending the flat top gives a better reference in the bender. I do profile the back and cut the top to its maximum width. Don't forget the blocks need to be taller on the edge away from the sides to allow for the doming, unless they are pre-domed, not easy to do accurately, they cannot be glued in place with the sides in the dish or the inside edge will be too low.

A full explanation would take several pages I'm afraid.

Your problem though seems to stem from using predrilled blocks. I don't drill my block until the top and back are on, then I fit the neck and using a punch mark the neck where the inserts are to go.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

If you look at my site on getting the proper contour you will see the steps and some pix.
   I set the set into the mold , then I square the top then do the back radius , then with the top being used as a datum point I will rough the top contour and true things up one all is in place IE blocks kefing etc. Then once in the mold it stays there till the top and back are on.
    No matter how careful you are you can't get the set back in the mold exactly as it was .
john

[QUOTE=Hesh1956] And if John Watkins could chime in here I think he could tell us how he does this too please?
[/QUOTE]

Happy to, Bud.

The neck blocks and semi-custom necks that I produce all have a 1.5 degree angle built in as a "head-start" for fitting. That number is meant to be less than what's required for most any design so that the final adjustments do not move the neck joint away from the 14th fret.

The neck blocks also have a .105" vertical offset from the necks to allow room for the top of the guitar to fit. This is also meant to be just below what any design might call for.

So here's what I would do; pre-shape your sides to be as close as possible and then bend them. Place your mold over a radius dish and shim it at the neck block to allow the sides to sit in it at the proper "attitude". Set your protractor or bevel transfer gauge to your desired, finished neck angle according to your design.

With your neck block temporarily clamped in, mark a line on the side of the neck block that terminates at the top of the bolt side. It should show you the sliver of material that is going to come off when you sand to the final angle. Glue in your neck block so that the top of the sides lines up with that line, NOT with the top of the block. With a little luck that removed amount will correspond directly to the amount that you needed to remove anyway to fit your top (.02"-.04").

If you do this correctly, your sandpaper will reach the bolt-side of the neck block and the same time that it reaches the top of the sides.

If your neck angle differs drastically from the 1.5 degree original measurement, then you may need to trim the underside of the tenon a little in order to get it to sit down.

Make sense?John Watkins39077.4054976852

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John Watkins
CNC Guitar Parts

John has it .. you cant glue everything together on aflat surface, then radius and expect the blocks to not have a bunch sanded off. You had to leave some amount of side wood proud of the blocks top at least (bottom too unles you are after a shallower neck heel height). Remember the highest point of the sides in the bowl will be at the waist - so whats happening when you sand Hesh is that you are trying to get the waist area to touch the bowl, and until you sand the blocks lower it wont get there. My neck block is always glued more in the middle of an unprofiled bent side - then when you mark the profile of the bowl to the side from the bowl, its all taken care of. When deciding on neck and tail heights, I tell my students that the size of the rough blocks will be close to the finished heights - you will sand dome off to get the radius on them, but then the top and back get glued on and the height is restored.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Hesh .. lay a straight edge across your 25 ft bowl - what is the max depth (about 1/4 right) ??? thats how much you shim the blocks if your top edge of the sides is flat, ready to be profiled. Everything else sounds about right for your method (I dont do it that way, but thats me !!)

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

   Actually the neck block if you carry that proud about 1/8 should give you ample trueing room. I think you may have the concept and once you do it ,you will perfect your technique pretty fast
john