|
|
#1
12-18-2013, 06:50 PM
|
|||
|
|||
Top and Back Radius
I am working on my first build and I am at the point where I am about to radius the top and back. I have a 25' contour dish for the top. How would it affect the back if I used the same 25'. I can still contour the back a 16' but I dont have a dish, but made something to shape the braces. I need help ASAP!!! Got any tips?
|
|
#2
12-19-2013, 09:44 AM
|
|||
|
|||
|
Quote:
-2 clamps (i like bessy's or jorgensen's) and something to serve as a spreader/clamping bar -brace(s) -glue -guitar back -compression pad -workbench i've done it and it works. although i used our new bath mat instead. good luck!
|
|
#3
12-20-2013, 03:57 AM
|
|||
|
|||
|
It's pretty nice to be able to contour the rims to the radius of the back plate with a sanding dish. It can be done carefully with a sanding stick or block plane though. An advantage of a tighter back radius is that it raises the pitch of the back, which should be higher than the top,in traditional building. If you went ahead with a 25' radius back, I would consider adding some height to the back braces.
|
|
#4
12-23-2013, 08:29 PM
|
|||
|
|||
|
Gibson has used the same radius for both top and back forever, and it seems to work for them.
Quote:
|
|
#6
12-24-2013, 03:05 PM
|
|||
|
|||
|
Cut the other radius on the flat side of a piece of stable 2X4 wood, glue on sandpaper, drill a hole in the center, and spin this around your rim keeping the center/hole in the same place. If the sides have been cut close to the right shape before bending, then this is quick and easy, and if not, then it will take a bit more time.
|
|
#7
12-24-2013, 03:31 PM
|
|||
|
|||
|
Quote:
I have never used a radius dish. I pre-profile the sides for the back radius, and use a 3/4" thick hardwood stick with the radius cut into it for a gauge. I arch the kerfing with a block plane and sanding blocks, and check it with my gauge. For gluing arched braces in a go-bar deck, I use curved backers that are bandsawn from a 2 X 4, so they are 1 1/2" wide and about 1/2" thick on the ends. It is possible to sand the backer smooth after bandsawing it out, but I found it to be easier and just as effective to lay a thin strip of basswood on it....between the backer and the top or back. The basswood strips I use are 1 1/8" wide, and about 5/32" thick. They are flexible enough to conform to the curvature, and soft enough to prevent marking the softer woods like cedar or Engelmann.
|
|
#8
12-24-2013, 06:05 PM
|
|||
|
|||
|
Cody: I don't glue up in a radius disc. I radius the braces then glue and clamp in place with cam clamps. What I am careful with is putting some sort of protection on the show faces of top and back so they are not marked. One must also be careful of placing clamps in the correct position so as not to go over the edge of a brace and crack a plate. It is not hard to do correctly just requires awareness. It is a slower process then gluing all the braces at once with go bars but to me the results are just as good.
Tom
__________________
A person who has never made a mistake has never made anything
|
|
#9
12-25-2013, 03:26 AM
|
|||
|
|||
|
I built a "cradle" for making my backs, with 4 radiused pieces of 3/4" wood glued to a flat piece of plywood. Each piece of radiused wood is covered with a thin layer of cork (available at most office supply stores). I'd send a link to a photo, but I am in Japan now until after new years and my workshop is too far away to grab a quick photo.
I usually clamp/glue 2 back braces at a time, using only 2 clamps per 2 braces, but using a series of wood sticks that I stack like kind of like the game "Jenga" to avoid the need of 4 braces per clamp. I get 4 clamping points on each brace with only 2 clamps per 2 braces. I've never used go-bars, but I understand their functionality and ease in utility. However, there are other ways to achieve simple utility with great functionality.
__________________
---- Ned Milburn NSDCC Master Artisan Dartmouth, Nova Scotia
|
|
#10
01-05-2014, 04:17 PM
|
|||
|
|||
|
Quote:
|
