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Purple Heart Build , And Jig Idea ! Updated pics
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Author:  WudWerkr [ Wed Mar 30, 2011 9:13 am ]
Post subject:  Purple Heart Build , And Jig Idea ! Updated pics
I have started another build in my "spare time " laughing6-hehe Mainly to get my jig idea going . This is my First Guitar , so hang on for the list of newbie Mistakes .

The main point of this thread is to get the jig idea going.

I have made , designed a jig/gobar set up all in one . It isnt same as a standard go/bar deck , I have thought this out based on lack of space for a dedicated go/bar set up.

So here goes;

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As you can see I have used 5/16-18 tee nuts glued in place withe gorrilla glue . Why 5/16-18 ? ummmmmmm cause i had them ! laughing6-hehe The jig has legs to set it and have the sides centered . The center former has legs that can screw in either side as well to keep it level . That helps set the former in place with less effort . all the legs screw in and out of the same holes that the go bar deck uses . NOW the MAIN diffrence in the go bar deck is I only have 18" . What I have done is ordered 5/16" Fibreglass rods and Rubber Tips . I am planning on using them straight and apply pressure by tightening the top plate ( 4 ) Nuts down slowly and evenly .


I will post the pics of the continued effort as I get them .
Author:  Chris Ensor [ Wed Mar 30, 2011 9:26 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
I love your jig. I would however recommend using 2 or 3 pieces of 3/4 ply for the top rather than one. Each go-bar exerts about 7 lbs of pressure. Use 20 to 30 go-bars, and you are looking at around 200lbs of pressure. That is enough to distort a single layer of 3/4 ply.

I also love your mold spreader. I think I will steal that idea and use it on all of my molds. :lol: WaHaHa WaHaHa (evil laugh)
Author:  Barry Daniels [ Wed Mar 30, 2011 9:33 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
The challenge will be how to stop the go bars from pushing the ribs out of the form.
Author:  WudWerkr [ Wed Mar 30, 2011 9:38 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Barry Daniels wrote:
The challenge will be how to stop the go bars from pushing the ribs out of the form.


? Not sure I follow ? Elaborate please , Wanna make sure I havent over looked anything , so I would appreciate input ! [:Y:]


I have made a jig that is approx 1" wide x 3/4" plywood the shape of the guitar with holes in place for go bars to be stationed in place . This SHOULD help keep the pressure even. If it works Like I have thought it out , it SHOULD require less pressure . I will post that pic when I get bars in place .
Author:  WaddyThomson [ Wed Mar 30, 2011 9:45 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
I'm going to disagree on the single layer of 3/4" ply. It works fine. I can stand on a piece of 3/4" ply between a couple of boards the same distance apart as a guitar body is long, and get little deflection - 250 lbs +/-. I use a single piece supported by 4 threaded posts over my solera, in a similar manner to this, and there is no deflection with 28 go-bars in place at exactly 9 lbs each - mine are spring loaded bars, not bent stock. The point is that the weight is distributed over a broad area, not all in one point. I can't speak to pushing the body out of the mold, which also seems to me could be a problem.
Author:  Alain Moisan [ Wed Mar 30, 2011 9:55 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Barry is right. Unless you have some system that attaches the sides to the mould, the go-bars will push it out. Or, seen differently, will push the entire setup (mould/go-bar deck) up and away from the guitar.
Author:  WudWerkr [ Wed Mar 30, 2011 10:07 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Alain Moisan wrote:
Barry is right. Unless you have some system that attaches the sides to the mould, the go-bars will push it out. Or, seen differently, will push the entire setup (mould/go-bar deck) up and away from the guitar.



Note in the pic the Mould is clamped to the table and the legs are adjustable , I can adjust the mould up so that it is within a 1/4" of the top of the side . and clamped to the table it will not raise , and the bars are applying down pressure . Thanks for the input ! [:Y:]
Author:  Alain Moisan [ Wed Mar 30, 2011 11:52 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
WudWerkr wrote:
Note in the pic the Mould is clamped to the table


Indeed it is. Didn't notice, sorry. But then what blocks the sides from sliding down the mold? You can't have a full contact if you have some sort of a tappered back and/or radius in the sides...?

Again, maybe I'm just missing something...
Author:  WudWerkr [ Wed Mar 30, 2011 12:18 pm ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Quote:
But then what blocks the sides from sliding down the mold? You can't have a full contact if you have some sort of a tappered back and/or radius in the sides...?


You make a good point here ! Thanks ! [clap]

In this particular set up there is no tapered sides , Havent devised a way to do that yet , but its in my mind . So the sides are equal . Under the mould is ( 4 ) steel legs that screw in to hold the mold up , clamps to hold it down and table holds sides and top agains gobar pressure . My thoughts on a curved / tapered back would be a mould bottom plate / radius dish cut to match desired taper that could be bolted to bottom of jig using leg threads so that the sides would set level . I guess the jigs ability is open to various possiblibilites . All in due time !

Thanks for your observations ! I really appreciate the feed back . [:Y:]
Author:  Zach Ehley [ Wed Mar 30, 2011 5:18 pm ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Good luck getting those spreaders out of the soundhole. :lol:
Author:  Jeff Highland [ Wed Mar 30, 2011 5:56 pm ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Will those spreaders even get out past the linings now?
Author:  ChuckH [ Wed Mar 30, 2011 7:41 pm ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Hey Big Jim,
Congrats on your first guitar. Just left Southern Illinois after cutting up some binding and crap. Just got in to Columbus, GA. Man i hate driving. Anyway, I like your jig setup. Looks like you've got all your bases covered.

Good luck on your first.

Hutch
Author:  nickton [ Thu Mar 31, 2011 2:20 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
I guess you don't really use side braces either... eek
Author:  WudWerkr [ Thu Mar 31, 2011 9:01 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Jeff Highland wrote:
Will those spreaders even get out past the linings now?



Quote:
Good luck getting those spreaders out of the soundhole


Quote:
I guess you don't really use side braces either...


laughing6-hehe Yes they will get out past the linings with plenty of room , and I have a HUGE sound hole laughing6-hehe No actually the tops not on yet .

Thanks for looking . I worked on the gobars last night and will post a pic of the back being glued on . YES I put my back on first and top last , at least on this one I am . Ive built several Mando's but this being my first guitar , I may change my direction and do top first . Right now Im just designing the jig to get me through the build .

I have side braces made , they will be glued in after the top or bottom is glued on and the spreaders removed.
Author:  WudWerkr [ Thu Mar 31, 2011 9:12 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
I also braced the top with alaskan spruce . I made the braces go over the center strip .

Has anyone even done this ? Good idea ? Bad idea ? The reason I am trying this is because on one back I made the center strip was desernable as a small flat spot after it was glued on . So i thunked Id try this .

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Author:  B. Howard [ Sun Apr 03, 2011 6:11 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
What type of finish are you using on Purpleheart? I've built some things from it over the years as have some of my co-workers ( no guitars though) and every one of them turned a rather unpleasant brown in a few years. This despite using different finishes. I even re-finished one piece I made and it did the same all over again. We tried varnish, poly, even buffed beeswax, all the same. A real shame as these were really beautiful things when first done. Would like to use some for accents, if I knew it would stay the same color through the life of the instrument.
Brian
Author:  WudWerkr [ Sun Apr 03, 2011 7:41 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
I dont know yet , probably nitro-laq. I have heard this as well that it tends to turn brown . I have thought about the idea of using a stain b4 laq, to help keep it that color . But really havent decided what to do at this point .

MAYBE someone else will pop in and have another idea ?
Author:  Bill Hodge [ Sun Apr 03, 2011 9:21 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Mornin' Big Jim!

Nice concept on the jig, if you find it works well, ya done good! [:Y:] A couple of observations, it looks as though the annular rings on the tail block are running perpendicular to the rings on sides. I may be wrong but I believe you're asking for future troubles on that one because it is highly likely it will split over time (or sooner). In addition, it appears as though the center strip has the annular rings running parallel to the ones on the back. If that's so, you're likely going to have a split back over time. You really want the center strip to be made up of a piece that runs perpendicular to the rings on the back. At least, this is according to what I have learned over the years. I suppose if the piece is flatsawn that might be OK but I've not tried it or seen it done. Best to you on your first build!
Author:  runamuck [ Sun Apr 03, 2011 10:18 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
WaddyThomson wrote:
I'm going to disagree on the single layer of 3/4" ply. It works fine. I can stand on a piece of 3/4" ply between a couple of boards the same distance apart as a guitar body is long, and get little deflection - 250 lbs +/-. I use a single piece supported by 4 threaded posts over my solera, in a similar manner to this, and there is no deflection with 28 go-bars in place at exactly 9 lbs each - mine are spring loaded bars, not bent stock. The point is that the weight is distributed over a broad area, not all in one point. I can't speak to pushing the body out of the mold, which also seems to me could be a problem.



I think you're not aware of the deflection because of your spring loaded bars. You'll find that there is enough
deflection in a 2' X 2' piece of MDF that standard bars will tend to sometimes fall out as ones are added.

Try it.
Author:  WudWerkr [ Sun Apr 03, 2011 10:41 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Quote:
A couple of observations, it looks as though the annular rings on the tail block are running perpendicular to the rings on sides. I may be wrong but I believe you're asking for future troubles on that one because it is highly likely it will split over time (or sooner). In addition, it appears as though the center strip has the annular rings running parallel to the ones on the back. If that's so, you're likely going to have a split back over time. You really want the center strip to be made up of a piece that runs perpendicular to the rings on the back.


Thanks , thats a couple of points I had not considered . In the words of the great builder " Yoda " Much to be learned , there is ! :lol:

BTW After much consideration............ , about 10 min, ................I decided to go to spring loaded gobars . I am making them as we speak .
Author:  WudWerkr [ Tue Apr 12, 2011 12:04 pm ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
After checking out the Ideas talked about , I went with the Spring Loaded Go-Bars . I made these from 5/16" fibreglass rod and 3/4" OD Fibreglass tube and rubber bumpers . The spring tension inside is 15lbs at max compression at 2-1/2" . I am at 1-7/8" here which gives me approx 12lbs of pressure as you see them in use .

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Thanks for the spring loaded gobar idea [:Y:]

Also I did brace the top with X brace and end braces . Maybe not Necess , but scraps cheap ! laughing6-hehe
Author:  amcardon [ Tue May 03, 2011 12:44 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
WudWerkr wrote:
I dont know yet , probably nitro-laq. I have heard this as well that it tends to turn brown . I have thought about the idea of using a stain b4 laq, to help keep it that color . But really havent decided what to do at this point .

MAYBE someone else will pop in and have another idea ?


Purpleheart will brown due to UV oxidation, I know with knife handles you have to use a UV blocking finish if you don't want it to turn brown in a couple months... I know at my local Woodcrafters they have UV blocking finishes; I've never tried it and I don't have a specific one to try (for all I know, since this thread is a couple weeks old, you already figured something out) but figured I could at least pipe in...
Author:  Kamusur [ Tue May 03, 2011 6:15 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Great solution to some probs with your system Woody ty for sharin
Keep up the wud werk.

Steve
Author:  WudWerkr [ Tue May 03, 2011 7:54 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
Quote:
Purpleheart will brown due to UV oxidation, I know with knife handles you have to use a UV blocking finish if you don't want it to turn brown in a couple months... I know at my local Woodcrafters they have UV blocking finishes; I've never tried it and I don't have a specific one to try (for all I know, since this thread is a couple weeks old, you already figured something out) but figured I could at least pipe in


I have not done anything yet , other than buy some purple stain and mix it with cherry stain and came up with a stain color that matched the purple heart. I then stained a piece of scrap and you couldnt tell it from one without stain . Will this work idunno

Maybe that along with uv protection finish ? havent decided yet .
Author:  WudWerkr [ Tue May 03, 2011 9:09 am ]
Post subject:  Re: Purple Heart Build , And Jig Idea !
A few more pics of the purple heart build . I have made several mistakes and am making notes . The jig idea is working quite well , though I did have one set back . All the comments I had were about the sides pushing out , or the jig lifting and I covered those bases , what I didnt think about and no one else did was that the Plywood might de-laminate from the pressure .......... IT DID . laughing6-hehe

I had to reglue it and used drywall screws around the perimeter to make it stable .

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I know this is not even close to the quality most of you have , maybe someday .
Thanks for looking and I appreciate all the intrest and welcome "constructive Criticizm"
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