Sides are too tall- Now what?

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mjmeehan
Posts: 191
Joined: Fri Aug 28, 2009 8:58 am
Location: Bethlehem, Pennsylvania

Sides are too tall- Now what?

Post by mjmeehan »

The sides I received for my Jumbo build are too tall, by almost 1/8" at the neck block and 1/4" at the tailblock. Since the sides are already bent I do not like the idea of trimming them down. Would it be acceptable to "add on" to the blocks and essentially shim this distance OR does that make the guitar too thick? OR will this have some weird effect on tone? Or some other effect I haven't imagined yet?

I'm a pretty big dude as it is, so the extra size would not be a problem for me, it's the idea of gluing an add on to my bolt-on neck block that has me concerned.

OR am I thinking about this too much?
JJDonohue

Re: Sides are too tall- Now what?

Post by JJDonohue »

They will come down to the level of the blocks when you sand them to establish the profiles. Adding to the blocks would be the wrong way to go.
kencierp

Re: Sides are too tall- Now what?

Post by kencierp »

Have you contacted the kit supplier regarding the issue? How did you determine the degree of the error? What neck and tail "FINISHED" height targets are you using? The neck and tail blocks should be slightly proud of the back edge of the sides when glued in place -- after contouring the back edge of the rim, the inner edges of the blocks will actually be higher than the sides, both at the tail and neck blocks.
Freeman

Re: Sides are too tall- Now what?

Post by Freeman »

You can make a deeper body, but really should think about that from the get-go (get neck and tail blocks that are long enough, make sure that your neck heel will be deep enough, and that you really want the deeper body (both my OM12 and my tricone are deeper than normal).

However, in your case, your sides are perfectly normal. They are almost always too tall and will be parallel. Choose one edge to be the top - either the straightest or based on the grain. I reference everything to that edge - top kerfing and the neck and tail blocks. Then from your plans transfer a bunch of measurements referenced from that edge to where the back will be - make pairs of marks on each side at the same points. I do it on the inside of the sides, then run a piece of masking tape around connecting the dots. Draw a line at the edge of the masking tape, glue your end blocks and kerfing in.

Once kerfed you can take that excess down with planes, chisels, a flush cut router - work with the grain (your cuts will be towards the neck because the sides slope in that direction. Leave the end blocks standing proud - they will come down as you dome the back.

Once you have the edges down to the kerfing you can do whatever you want as far as doming (or not, see other threads). I believe in angling the kerfing and end blocks, so I sand with either a radiused sanding block or in a radius dish, apparently others make the kerfing flat and glue to that. Because of the way the sides get thinner as you go towards the neck the whole thing is kind of a compound geometry, but it all seems to work out.
kencierp

Re: Sides are too tall- Now what?

Post by kencierp »

Just to clarify a comment from above -- KMG kits come with the sides ready to use, the complex profiling is completed in our shop, the inner wasit position is marked and used for registration in the mold so ends can be precisely trimmed. I do believe the kits from Martin are also profiled --- my concern here would be, if a "Martin kit" prehaps the blocks do not match the sides -- which seems common with the third/forth party kits. That is why I inquired about where the dims originated --- a double check of the parts on hand.
Last edited by kencierp on Thu Aug 26, 2010 3:40 pm, edited 1 time in total.
mjmeehan
Posts: 191
Joined: Fri Aug 28, 2009 8:58 am
Location: Bethlehem, Pennsylvania

Re: Sides are too tall- Now what?

Post by mjmeehan »

Ken, I'm working off plans from LMI not really a kit. I assumed the sides would be cut with the plan in mind, not over sized. LMI recommended trimming them down with a band saw or coping saw using a measuring method similar to what Freeman suggested.

A trip to Guitarmakers Connection tomorrow and I can see what they have in stock for end blocks or blanks.

For further clarification, I determined that the sides were too tall when I measured them and realized that I would not have the desired neck and end block overhang on the sides. Actual neck block height is 4 1/16" and the end block is 4 3/4" on the plan.
kencierp

Re: Sides are too tall- Now what?

Post by kencierp »

Yeah-- LMI usually only puts a taper on the length -- somewhere in the old forum Bill Cory had a nice post regarding the system he used to make a more accurate profile plot for the back edge -- might be worth a look?
mjmeehan
Posts: 191
Joined: Fri Aug 28, 2009 8:58 am
Location: Bethlehem, Pennsylvania

Re: Sides are too tall- Now what?

Post by mjmeehan »

Ken, I found it! I'm going to do as Freeman (and Bill) outlined but instead of gluing the kerfing I will stop with the line and trim it there, then add the kerfing.

Another "learning curve" for me and I thank you all for the direction. As a friend of mine said "you're gonna have this guitar for the next 40-50 years. Go slow, take your time and get it right... Now get to work!"
tippie53
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Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
Contact:

Re: Sides are too tall- Now what?

Post by tippie53 »

Like ken the sides from our process will have the depth and contour installed into the sides. The profiling process is something you don't want to leave to chance. This vid will help show one of many techniques that will work.
http://www.youtube.com/watch?v=QYHPCeVRUA4
Good luck and enjoy the build .
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
mjmeehan
Posts: 191
Joined: Fri Aug 28, 2009 8:58 am
Location: Bethlehem, Pennsylvania

Re: Sides are too tall- Now what?

Post by mjmeehan »

Thanks, John. I don't have a radius dish but I get the point and feel that with slow, careful attention I can get there.
Excellent link.
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