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Top or Back first?
http://www-.luthiersforum.com/forum/viewtopic.php?f=10102&t=4628		 Page 1 of 1
Author:  Bill N [ Fri Jan 20, 2006 4:03 am ]
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I know this may well sound like a dumb question to you experienced builders but here goes...
On a steel string
Which do you glue to the rim first? The top or the back?
and why?
I have now done it both ways and can not figure out which way I prefer...
or do some of you glue both at the same time?
Author:  TonyKarol [ Fri Jan 20, 2006 4:08 am ]
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Back first - then you can clean up any squeeze out that may be visible thru the soundhole.
Author:  Serge Poirier [ Fri Jan 20, 2006 4:20 am ]
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What Tony says and it also gives you more time to fine tune the top.
Author:  Laurent Brondel [ Fri Jan 20, 2006 4:24 am ]
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It seems people using molds glue the back first, for the reason Tony stated.
Some others building "free-hand" glue the neck & end blocks to the top first,
and then glue the sides, one by one to the blocks and top and finally glue
the back on. I think classical builders using the traditional method do that
too, except the end block is also the neck. You got to have your square
ready and maybe a spare pair of hands to hold everything in place, glue and
clamp at the same time…
Author:  Dave White [ Fri Jan 20, 2006 5:00 am ]
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I join the sides to the end-blocks, brace the back and top, shape the sides, fit linings, do the side struts and flying buttress braces. Then I notch the linings and cut the neck block for the top A frame braces, make sure the top and back fits snug (dry run) one at a time. Then I glue the back first (for better cleanup of the most visible areas as the others have said) and finally the top.

I used to do it the Cumpiano way with neck and heel block glued to the top, but with tops that have big arches this method doesn't work very well at all.

I like to have as little clamping as possible and get away with just 2 - the top and back are glued on largely with the LMI brown tape to hold them down. That's partly why I moved to X braced backs.

Sorry - long answer to your simple question!
Author:  peterm [ Fri Jan 20, 2006 5:12 am ]
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I like to glue on the top first, just me I guess....but that way I can make sure the X-braces are neatly tucked under the kerfing for better top strength and tone. I glue on the back after and carefully make sure I clean the squeeze out throught the sound hole. Normally there isn't much to clean out and I easily get to it with a moist paper towel!
May not be the best way but works great for me!
Author:  Jimmy Caldwell [ Fri Jan 20, 2006 5:14 am ]
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For me, it depends on the top bracing. If it's a traditional x-brace, I put the back on first. I also build Kasha-Braced guitars, and on those, I put the top on first as there's quite a bit of bracing that can't be done until the top is on.

Bottom line is there's no "correct" way to do it. Whatever you get the best results with is the way to do it, and it takes awhile to make that determination.
Author:  LarryH [ Fri Jan 20, 2006 5:27 am ]
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I just put the top on first because I wanted to position the A Frame braces under the heel block extention and there would be no way to do this (in my little mind that is) with the back on. Squeeze out and the visual through the sound hole is still not a major issue with me as I am still hoping the thing will be playable when finished.

Larry
Author:  Alain Desforges [ Fri Jan 20, 2006 5:29 am ]
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I like to glue the top and back to the end-block and head-block and then I glue on the sides, always making sure to put on the cutaway last...
Author:  Dave White [ Fri Jan 20, 2006 5:46 am ]
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[QUOTE=LarryH] I just put the top on first because I wanted to position the A Frame braces under the heel block extention and there would be no way to do this (in my little mind that is) with the back on.
Larry[/QUOTE]

Larry,

You can do the top fit as a "dry run" first with the back off as if you were going to glue the top - this is how I get the A frame braces to fit snugly into the top of the neck block. Then when it all fits, glue on the back first, and then the top.Dave White38737.5748263889
Author:  Philip Perdue [ Fri Jan 20, 2006 5:47 am ]
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I have no practical knowledge or experience in this area but do have a thought about attaching the top first. Would it be plausible to only finish your top bracing ends enough to attach to the rim and then do the final shaping? Would you then be able to complete your brace shaping as you tune the plate in place while using a signal generator and glitter patters? It would seem that this would allow you to have a better understanding of the functional characteristics of the top. I’m sure that Alan Carruth may want to reply if he views this. He would be the expert.

It just seems that with most things you build you complete the project, fine tune, and then finish. With guitars, as I understand it, you tune the top then close the box and finish. I’m not sure if anyone continues to tune the top plate once it is attached or for that matter if it’s even feasible.

Philip
Author:  old man [ Fri Jan 20, 2006 6:25 am ]
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I follow exactly the same routine that Dave described except I use the go bar deck to clamp.

Ron
Author:  Dave Rector [ Fri Jan 20, 2006 8:28 am ]
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I glue on the back first. Same reason, cleanup is easier.
Author:  Michael Dale Payne [ Fri Jan 20, 2006 9:16 am ]
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[QUOTE=konacat] I have no practical knowledge or experience in this area but do have a thought about attaching the top first. Would it be plausible to only finish your top bracing ends enough to attach to the rim and then do the final shaping? Would you then be able to complete your brace shaping as you tune the plate in place while using a signal generator and glitter patters? It would seem that this would allow you to have a better understanding of the functional characteristics of the top. I’m sure that Alan Carruth may want to reply if he views this. He would be the expert.

It just seems that with most things you build you complete the project, fine tune, and then finish. With guitars, as I understand it, you tune the top then close the box and finish. I’m not sure if anyone continues to tune the top plate once it is attached or for that matter if it’s even feasible.

Philip[/QUOTE]
I do hope Allen jumps on this    My thinking on this issue is that when you tune a loose top you are tuning just the tops inherent resonate characteristics if you tune the top after it is attached to the rim then you are tuning the assembly and the criteria you tune to would need to change accordingly to achieve the results desired because the diaphragm is no longer free but is now suspended. That does not mean that there is no value in this just that you would need different guidelines to work to.

Author:  ggdelazzer [ Fri Jan 20, 2006 10:33 am ]
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Top first and then I shave the braces to the final shape and thickness. I find the top tuning easier without the back glued in place
Gg
Author:  tippie53 [ Fri Jan 20, 2006 11:47 am ]
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   I do both at one time but then I have a press.
   john hall
Author:  LarryH [ Fri Jan 20, 2006 1:13 pm ]
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[QUOTE=Dave White] [QUOTE=LarryH] I just put the top on first because I wanted to position the A Frame braces under the heel block extention and there would be no way to do this (in my little mind that is) with the back on.
Larry[/QUOTE]

Larry,

You can do the top fit as a "dry run" first with the back off as if you were going to glue the top - this is how I get the A frame braces to fit snugly into the top of the neck block. Then when it all fits, glue on the back first, and then the top.[/QUOTE]

Thanks Dave, very helpful as usual. Now that I've done it once it seems like a good plan to do the back first.

Larry
Author:  LanceK [ Fri Jan 20, 2006 1:59 pm ]
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I do the back first for the same reason aready mentioned. Gotta have a clean box! I would probably freak out with anticipation if I did the top and back at the same time, just knowing that there will be squeezout that I cant get to! Way down in the bowls of the lower bouts Its back first for me!
Author:  arvey [ Sat Jan 21, 2006 3:57 am ]
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I have done both back first and top first for the above reasons. Really not convinced which is best. One time I even dod both the back and top at the same time. Worked but everything had to be fitted and go smooth so I haven't done it that way since. I use the go bar deck to clamp with.
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