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Hehehe...

I'm seriously considering inserting some bits of steel rod with a pin in into holes in the molds I've made. Taking the magnets off = pulling out the steel rod (with hand to catch the magnet, natch), mold fully supporting everything. I'm thinking embedding a magnet or two into a shaped caul for the waist would be the way to go there.

Hmmm...

[QUOTE=Mattia Valente] Hehehe...

I'm seriously considering inserting some bits of steel rod with a pin in into holes in the molds I've made. Taking the magnets off = pulling out the steel rod (with hand to catch the magnet, natch), mold fully supporting everything. I'm thinking embedding a magnet or two into a shaped caul for the waist would be the way to go there.

Hmmm...[/QUOTE]

SNIF ...SNIFF... I can smell overheating cells here!

I am assuming the magnets would only be removed... after the back was glued on,otherwise, what is the point to using them.That is where the tricky part begins.. how do you get the magnets out ,once the back is glued?

Does anyone know exactly what/how this jig is used ?? My guess is the top is already glued on, as you can see a couple alignment lines at the tail wedge on the base board, and that he has some kind of clamping caul that will rest on top of the back once its positioned and glue applied, and then there are tabs or something that the cam clamps at each end use to provide the pressure.

Not sure, but it looks neat - notice how the side wall cauls are movable as they are only held against the outer blocks by the sideways cam clamps - he could do any of his body shapes with this I take it. Looks like the soundhole clamp board could be loosened from the bottom, then removed thru the hole.TonyKarol38853.7136689815

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Ken: how is that more difficult than removing spreaders after the back's glued in place? Easier, I'd think. I can just reach in and touch most bits of the inside of my guitars through the soundhole, and if I can't...well, my girlfriend's arms are quite a bit smaller than mine..

Right Mattia - but can she grab onto 50lbs worth of magnetic pull and get them loose thru a soundhole ???

Spreaders, at least mine, come out pretty easily. They come completely apart and are removed in about 30 seconds. They are shaped to hold the waist better than any flat magnet could. I cant reach the end block in my bigger models, but the neck to tail block spreader can. These might be an added bonus if you needed extra support on the sides like where Kevin has them, but I find spreaders easier.

I am wondering after taking another look, if the bolts in the outer cauls arent removed with the wood staying put - the magnets would then fall off inside, and be easy to get out. Those deeper ones would be pretty hard to reach in and pull out once the back is on IMO. That guitar body is fairly long, over 20 inches, not sure of the model name, but its the one Bensusan has.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Yeah, you're probably right about the bolts. Also: It's 50lbs in full contact, with no wood between. I'd imagine it's less with them in (my mind's saying 'inverse square law' for some reason). I'll order a few (cheap enough, after all) and do some experimentings. I'd think you could actually wrap/glue foam to the magnets, cushioun their fall, meaning no worries about holding them when they 'drop'

lee valley lists the 1x1/8 as 30 lbs between two metals. Putting two together, even with the 80-90 thou of side wood is going to be a lot - even if its half, 30 lbs is plenty to try to pry apart.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

It would be nice if K.Ryan would join our forum here and explain everything himself.I wonder if he participates in any forums?

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Anderson Guitars
Clearwater,Fl. 33755

Tony, I thought the same thing that the bolts could be backed out, but they look like nuts to me?

Maybe Kevin will chime in and set us stright

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Lance@LuthiersForum.com

Tony, I don't think you neet to "pry" it apart. You can make the metal part on the outside of the mold be hooked up to a bolt and a nut and then you can pull it appart by loosening the bolt! I think that the way Kevin does it. Look at the picture
Actually the bolt may be enough for the magnet.peterm38853.7918634259

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

The way I see the release mechanism is you open the cam clamp holding the Lshaped piece of wood with the bolt arangement in place. then simply pull that away using the L as a handle.

Russel, I think the L shaped piece of wood is just an adjustable way to accomodate different sizes of guitars. If you pull on that part to release if from the magnet you'd be forcing the side and maybe risk damaging it. By instead removing the bolt while the side is still supported by the "L-shaped" piece of wood that would not be a factor.peterm38853.8661574074

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

[QUOTE=Alain Desforges] I didn't think those magnets could exsert so much pressure...[/QUOTE]

I dare ya to try putting one in each of your front pants pocket



Grant

Is it possible that by touching the bolt with a similarly charged magnet it would be enough to repel the magnet on the other side?

Backing the bolt out while leaving the L shape in would certainly work but, based on what I hear people saying about Kevin Ryan, that would be too complicated.

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Eagles may soar, but weasels don't get sucked into jet engines.

[QUOTE=LanceK] Maybe Kevin will chime in and set us stright [/QUOTE]

Maybe someone should invite him...    It would seem a little obvious coming from Lance or I....

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Bill, thats a good question!! Even maybe touching it with the opposite side of the magnet, since magnets have different polarities in each side!
even though I beleive by backing up the bolts to set up the jig would make it a lot easier. If the bolts are permanently in place it will be pretty hard to place the magnets on the inside of the box in the proper place. By backing up the bolts you can position the magnets on the inside of the box while there is no pressure from the magnet and then slowly bring in the bolt.peterm38853.8714351852

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

With all the talk about pulls and the distance, what hasn't been considered is the metal OUTSIDE the mould. The "bolt" can be adjusted in size and/or recess inside the wooden support blocks to get the precise control he needs.

Just a thought, Steve

So...Kevin glues his tops on first!
That's the answer to last months question about what to glue on first! The "magnet" photos were just a ploy to distract you all from the obvious point of the entire thread!

What... that he writes inside his guitars with a Crayola?   

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

I've emailed Kevin about a local tonewood supplier and he got right back! He's about the only Luthier of note in my area.

He seemed like a nice guy and he does make some very nice jigs and very nice guitars, that's for sure!

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

Kevin Ryan really is a genius,


he sold his 500th guitar for $27,500!!!

Not having looked closely at Bensusan's when I saw it with him last year, you can also note that the lower back is radially braced - see all the notches in the linings - looks like 2 ladders up top, and 6 bars in the bottom bout.

I had thought about the bolt length inside the block to control the magnet pull - nothing to stop you from having the wood threaded, but it wouldnt last that long without a metal insert of sorts. But is does look like the exposed bolt portion is a washer and nut, not the bolt head as Peter mentions.

Anyway, as neat as this looks, I am in no rush to build one, my go bar deck does backs just fine. No room to put it either !!!

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Is it radial bracing, or an X with two extended fingers? Interesting...