Ken Parker Guitars

[Puff]

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[matthew]

Ken Parker does a really nice demountable that just slips in - and I would bet mega dollars to stale doughnuts that it works.
http://www.kenparkerarchtops.com/archtop.html

Interesting. I'd like to see how that works inside!

[Nick]

Interesting. I'd like to see how that works inside!

I think it slips into a close fitting pocket in the headblock Matthew & "up & down" adjustment is carried out by an adjustment screw on the rear of the body, turn it one way & the action is reduced & vice versa.


I seem to remember reading somewhere that the block holding the neck is CF (sometimes with wooden veneering to hide the CF look), not sure what the pocket is constructed of (although it's is probably some sort of composite also I would imagine). Don't think the sound is your 'typical' archtop sound but as his archtops have several 'innovations' it's hard to say if this type of neck to body coupling is solely the cause of this different sound or whether it's just one of the contributing factors. But it does raise an important question as to just how important this coupling is & just how big an overall effect it has on the sound?
Here's a youtube clip from Ken's site that gives the impression that these produce a more flatop rounded style of sound rather than the traditional jazz sound, even shows abit later in the clip (1 minute30 in) just how easy it is to change the action height.

youtu.be/

[Puff]

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[Allen]

I've been admiring Ken Parkers guitars for a couple of years now, and try as I might I can't figure out how that neck is attached. If you look through his website and blow up the pictures of the guitars where you can see into the neck block area, I just don't see one.

I've been dreaming of doing a neck like this for several instruments I've got kicking around in my head, and I'd sure like some insight onto possibilities with the design.

[jeffhigh]

As far as I could see when I looked at it a while back, the parker design is basically a tenon perpendicular to the neck into a mortice though the body with a captive bolt in the back of the body threading into the tenon.
Pretty simple really , but the devil is in the detail and getting each connection strong enough.

[Puff]

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[Allen]

Yes, but fitted into what?

I can only surmise from the images I see on his web site, and all the articles I've read about it, that there must be some sort of block that is either part of the top plate, or laminated to it. It does not extend to the back plate and laminate to sides as a conventional one would do. The photos on the web site are set up to not show the area of the top plate where that neck extension penetrates the top plate.

The neck adjuster must simply raise and lower the entire neck assembly. Not adjust the pitch as is the case in other adjustable necks. It makes me think that the tolerances must be spot on for this to work, and I'm left wondering how a set up like this handles the string tension found on steel string guitars.

In short, I'm left in awe of his design and ingenuity. And If I could justify the $30K to get one of his guitars in my hands to see what makes them tick, I'd do it in a flash.

[jeffhigh]

I would expect that there is a fairly large block between front and back, with a rectangular hole most of the way through, The bolt from the back would have a captive nut on it to retain it in position and thread into the neck tenon so that rotating it will raise and lower the neck.
The string tension and rotational forces would be resisted by the tight fitting rectangular tenon engaging in the mortice hole for most of the body depth.
Because you are only adjusting the height rather than the neck angle, there would not be much effect on tuning.
It's a great looking system very dramatic

[DarwinStrings]

In short, I'm left in awe of his design and ingenuity.

I agree Allen and getting adjustment without altering tuning is a stroke of brilliance.

[Allen]

That's what I thought at first Jeff, and perhaps it's done with mirrors. I just don't see any neck block in this shot, nor in any other one one his website that I could imagine this being the case.

http://www.kenparkerarchtops.com/BROWNI ... ortAlt.JPG

[DarwinStrings]

Isn't that the neck block you can see made of the same wood as the sides?

Jim

[jeffhigh]

I think I would agree with you Jim, there has to be something there

[matthew]

Well you can imagine what I'm thinking.

[Allen]

What about this shot then?

http://www.kenparkerarchtops.com/Resour ... side1K.jpg

[jeffhigh]

Yep that clarifies it.
You can see that the block extends onto the bass side of the back seam.
Look like it is veneered and contoured to match the cutaway shape

[Dominic]

You would want a pretty solid hole for the neck block to fit into. It worries me, all that string tension over time acting on the back edge of the hole in the body, particularly with that small block sitting so high with such leverage. It doesn't look very wide as it sits well inside the edge of the fingerboard. I would think there would have to be carbon fibre reinforcing in the body block. Last thing you would want is for the hole to start widening creating a looser fit. Imagine the vibrations you would get.

Where the block fits to the neck would be another potential weak spot. I think Ken uses carbon fibre necks that get a veneer. Perhaps the neck block is integral with the neck.
Anyway, I would love to see the whole thing being built, the pics so far have left more questions than answers.
Cheers
Dom

[J.F. Custom]

Beyond Carbon Fibre reinforcing in the block, there is nothing to suggest it is not a solid carbon neck block - with just a veneer surface, much as the neck is. As he suggests, the combination of carbon and aerospace (which is what exactly???) epoxy provides no 'creep' or possibility of movement over time. Depending on the way the block was constructed from the carbon, it should certainly provide enough support on the back edge as you could run the fibers continuously around the block with no 'end grain' or 'run-out' to concern you. You can also see in that last picture from Allen just how beefy the block is, behind the necks tenon.

As for the neck itself and the potential weak point, I was thinking on this too. My thoughts were as yours Dom - I'd guess the necks tenon is made integrally with the rest for continuity and strength as opposed to an 'inserted' block. A square hole in the veneer would then provide location for it, to be perhaps vacuum adhered after.

It would certainly have to be precise all round to fit and move smoothly in practical use. It is however a very smooth looking system - inside and out. No detail has been overlooked on that front though personally, I still feel uncomfortable with the carbon laminated binding left isolated - bar fight guitar or not it seems too fragile to knocks potentially splitting the sides.

Jeff, if there is a 'trapped nut', would you say there is also an insert in the tenon for the bolt? I wouldn't have thought Carbon would hold a good enough thread. We should see if we can collectively 'nut' this one out and perhaps one or some of us could give something similar a try when we do - would be a good learning experience. Making the neck could be tricky though... When you are getting US $30'000 for your guitar, I guess the cost of doing it this way is less of an obstacle.

Cheers,

Jeremy.

[matthew]

good idea I think jeremy - you might like to repost yr last comment in the previous hijacked thread!

[jeffhigh]

Yes Jeremy, I would expect that there would be an insert in the carbon fibre tenon to take the adjusting bolt. there would not be a lot of stress on this particular area though.

Dominic is right about the neck to tenon connection being quite vulnurable, particularly since Ken Parker has made it so small.

I would imagine there would be some sort of bolt fixing through the neck under the fingerboard into the tenon at the headstock side and at the bridge side.

Everything else is relatively straightforward, you would just have to make sure that the material beside the mortice was able to take the tensile forces induced by the sting tension.

I's a brilliant design, totally structurally inneficient, but so dramatic, looking like it is just floating there. and giving great access

[Kim]

I reckon there is some kind off CF foot which the riser block is attached to or part off. Like a one piece unit which is bonded to the underside of the top extending toward the back for a little way but also extending forward to meet the side right at the front of the guitar where it turns 90 degree....the strap button is probably used to lock the whole thing in place stabilizing the block and top so that the adjustment can work from the back. The 'foot' if it exists, would only need to be between 3 to 6mm to do the job and probably the same or even less at the 90.

(edit: revised down the thickness of CF required because I just checked 6mm and reckon it would be 'way' over kill)

Cheers

Kim

[Puff]

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[Kim]

Thanks Puff....I think..

It looks very much like Ken is laminating CF into his sides as well, probably .020 by the looks and most probably 45degree bias stock. If so, this gives a bit more weight to my theory that it is a type of foot, a single CF unit that supports the underside of the top beneath the neck block and is fixed to the side.



Cheers

Kim

[Kim]

You could also hide what ever you like with the way the sides a laid up. No rule that says you must glue all the layers together all the way up the side. With each veneer so thin it would bend like plastic. You could bond the outer veneer to the CF to form the side complete, but after the sound hole, the thin inner veneer could be bent in to join the other side internally making it appear like there is nothing inside the guitar when in fact the mechanism for adjustment is tucked into the cavity between the outer veneer/CF, and the inner veneer.

Cheers

Kim

[Kim]

OK, so I guess I should probably have read a bit more carefully what others have had to say...and looked at a few more images, but I think the veneer Jeff had already referred to well 'before' I made my last post would indeed be the inner layer of the side lay up as I suggested simply because it would be seamless. I also think that neck and tenon are indeed one piece and most probably veneered CF as Jeremy has suggested or maybe there is some Kevlar going on. Not sure but I think maybe the right angle of the tenon would be more suited to Kevlar construction but I am just guessing. But I still think it is most likely that the strap button is integral and is associated with a bracing system to over come the concerns that Dom has expressed in relation to a lack of support for the neck tenon from top to bottom.....to much reading of late to pay attention to the detail, looked at the first pic Allen linked to and shot from the hip..... sorry

If you have a close look at the neck to neck block joint in some of the images, you can see how it is simply too fluid to be a wood to anything joint...there is some impossible feathering going on which indicates a veneer over composite as Jeremy has suggested. But I think this is still quite doable with a bolt/screw into the tenon below the FB as was also mentioned by one of you guys. My conclusion to this point is that the tenon and the neck must be one piece, as Jeremy indicated. The inner side viewable through the sound port is just a veneer which hides the working mechanism as indicated by Jeff. That veneer is most likely to be the inner lay up of the sides for a seamless construction. The sides are laid up with a central ply of 45 degree bias CF to maintain stability and integrity to allow the airy design of the sound port. There is some form of central support to the neck tenon that is hidden behind the cavity created by the inner veneer which lends stability to the adjustment mechanism by way of securing the central tenon at mid point and that this support quite likely to be integrated into the CF reinforced side via the strap button screw.

Cheers

Kim