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I`d like to profile the sides before bending as in Colin`s tutorial.I want to profile the top side first and then the back getting my taper end to end according to the depth at each end allowing for top and back thickness and maybe a little extra ,maybe 3/16 or so for sanding later.Am I thinking correctly or what? I just always need a little guidance.
                            James

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James W Bolan
Nashville Tennessee

i side profiled this way and it worked great. only thing i did somewhat diff was i first drew a straight line on piece of construction paper the length of the side. at each end drew perpendicular (90 degree) line to the length of tail and neck then connected those for the taper of the back. then placed the tape with profile drawn on it to the corners. cut the shape out of the paper and did like Colin shows. worked good . just cut the wood a little bigger. ive only done this once and am on my 2nd built so take this advice knowing that.

Do you have the link for this?

 I need to get an even side profile with my box, but its already bent, any basic 'shortcut' advice.

If it`s already bent,just stick it in the appropriate radius dish ,scribe it ,plane it close,and then sand it till it fits nice and tight.This is the way I`ve done it in the past.I`m trying to eliminate a lot of hand planing.The tutorial page has Colin`s side profiling method I`m going to try .
                James

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James W Bolan
Nashville Tennessee

Oops Todd`s right.Glue the end blocks in first then sand the profile in the dish.That`s exactly the way I`ve done it.
              James
    

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James W Bolan
Nashville Tennessee

Most explanations to profiling I have found does not really match the dome intersection but rather account for general taper of the back from LB to UB. I profile the back pre-bend but leave the top flat till the blocks are glued up then I sand the actual dome into the side. install the linings and re sand the dome shape into the linings.

I have yet to see a profile method that accounts for the waist being the highest point of intersection with the dome. Profiling the back with the basic taper down save a good bit of sanding time. But if you are like me and have the dome fit perfect with the rim and linings the top is just as easy to sand down and not pre-profile

It is true Michael since the top isn`t really tapered just domed it`s pretty easy to sand after installing the blocks,as not a lot of material is being removed as is with the back.Plus it will give me a little more wiggle room.
                   Thanks
                   james

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James W Bolan
Nashville Tennessee

I too profile the back but leave the top flat before bending, just because this makes it easier to ensure the slat is square in the bender.

When the sides are bent and joined by the head and tail blocks then I'll use the stiff paper profile with both the back and top profiles on it, taped to the sides and draw in the profile for the top, plane to the line.



Then the linings are glued in and back and top dish sanded to bring the linings to the right shape. This only takes a minimum of sanding.

Colin

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

I've done this on my CNC....I model the side as I want it and then I can "unroll it" in CAD. I set it up specifically for the shape I use and the taper that I want..then just a matter of cutting it out. Works pretty good...!

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http://www.PeakeGuitars.com

How did you unroll your mesh or 3d solid to get it into a flat view?

I use Rhino, but you can probably do something similar in solid modeling apps such as SolidWorks using the sheet metal functions. I've never used many of the sheet metal functions (sheet metal is for wusses! ) but I would think that functionality is in there somewhere.

In Rhino you use the "unrollsrf" command.

I start by modeling the sides as they exist; bent and tapered. I really just model the outside surface...I am not actually creating a solid model of the sides. Then you just run the unrollsrf command and Rhino unrolls it for you. Seems to work pretty well..!

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http://www.PeakeGuitars.com