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Grain orientation of the end block.
http://luthiersforum.com/forum/viewtopic.php?f=10101&t=45410		 Page 1 of 2
Author:  Linus [ Mon Mar 23, 2015 1:02 pm ]
Post subject:  Grain orientation of the end block.
Should the grain orientation of the end block be parallel or 90 degrees of the orientation of the grain of the sides?

Will having it 90 degrees to the orientation of the sides have a higher incidence of gaps opening where the top/back meet the sides/end block?
Author:  Rodger Knox [ Mon Mar 23, 2015 1:08 pm ]
Post subject:  Re: Grain orientation of the end block.
I usually make the end block grain parallel to the sides so there's no endgrain glue joints.
I have also laminated the neck block.
Author:  rlrhett [ Mon Mar 23, 2015 1:17 pm ]
Post subject:  Re: Grain orientation of the end block.
I always do 90deg. The theory is that it would prevent expansion/contraction that might open a seam at the end graft.


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Author:  Ben-Had [ Mon Mar 23, 2015 1:35 pm ]
Post subject:  Re: Grain orientation of the end block.
I always go parallel to the sides.
Author:  Tom West [ Mon Mar 23, 2015 1:41 pm ]
Post subject:  Re: Grain orientation of the end block.
Linus: Both neck and tail block should run in the same direction as the sides. On the inside of the tail block I use a 1" by .125" vertical strip with the grain direction 90 degrees to the tail block. This in combination with the tail block and the tail wedge forms a solid 3 ply tail block. Some folks use Baltic birch plywood for the tail block.
Tom
Author:  Michaeldc [ Mon Mar 23, 2015 1:42 pm ]
Post subject:  Re: Grain orientation of the end block.
I use a piece of euro-ply. You won't damage the guitars if dropped on the end pin. Not everyone's cup of meat, it's just what I prefer to do...

M
Author:  kencierp [ Mon Mar 23, 2015 1:44 pm ]
Post subject:  Re: Grain orientation of the end block.
Slab cut or riff grain material -- parallel to the side grain. Also, I always (and part of our kit material package) add a 1/8" x 1" perpendicular spruce reinforcement in the center of the tail block. If nothing else sanding and/or planing the blocks will be significantly easier and you will not be gluing the plates to end grain, which in my view is never a good idea.
Author:  weslewis [ Mon Mar 23, 2015 2:02 pm ]
Post subject:  Re: Grain orientation of the end block.
3/4 inch ply with a endcap for looks
Author:  arie [ Mon Mar 23, 2015 2:21 pm ]
Post subject:  Re: Grain orientation of the end block.
3 piece Fleta design. center at 90, end caps parallel.
Author:  DennisK [ Mon Mar 23, 2015 2:22 pm ]
Post subject:  Re: Grain orientation of the end block.
kencierp wrote:
If nothing else sanding and/or planing the blocks will be significantly easier and you will not be gluing the plates to end grain, which in my view is never a good idea.

Tell that to the thousands of violin builders doing it every day :P But then, they do it specifically for the purpose of making the plates easier to remove for maintenance. And if you size the endgrain with hide glue and let it dry before gluing the plate, it makes a fairly strong bond. But IME, guitars need as much bond strength as they can get at the tail block, because when the plates expand and contract with humidity change, the stress is focused there. If the seam is going to pop, that's where it happens, unless the tail block has a wider glue area than the linings, in which case it may pop to either side of the block.

I make the tail block parallel to the side grain, but have been considering going to a two ply block, with one layer perpendicular to the sides and one parallel. Should greatly increase split resistance, and still leave some side grain for the plates to glue to.

Split resistance is mainly important if you're going to use a tapered endpin, which is basically a splitting wedge, and has to be tight enough to stress the block or you risk having it fall out in low humidity. And if you drop the guitar on its tail, it's pretty much guaranteed to drive the pin in hard enough to split a parallel grain tail block.

I'm more inclined toward screw-in strap pins though, so that's why I haven't gone plywood already. Still might split if dropped on it, but at least it's not a pre-loaded wedge.
Author:  Tom West [ Mon Mar 23, 2015 3:09 pm ]
Post subject:  Re: Grain orientation of the end block.
DennisK wrote:

Split resistance is mainly important if you're going to use a tapered endpin, which is basically a splitting wedge, and has to be tight enough to stress the block or you risk having it fall out in low humidity. And if you drop the guitar on its tail, it's pretty much guaranteed to drive the pin in hard enough to split a parallel grain tail block.


Yes sir..........!! But if you make a ply sandwich, it is very much less likely to happen. I have stopped using tapered end pins partly for this reason and because someone did a DIY of installing a pickup jack on one of my guitars. It was not pretty. I now install a pickup jack in all my guitars even if no pickup. At least it makes me feel more comfortable..........!! On two counts.
Tom
Author:  Bob Matthews [ Mon Mar 23, 2015 4:06 pm ]
Post subject:  Re: Grain orientation of the end block.
Grain parallel to the sides and I also add a lamination to the inside running vertically. No end pins for me.
Author:  kencierp [ Mon Mar 23, 2015 4:07 pm ]
Post subject:  Re: Grain orientation of the end block.
Quote:
Tell that to the thousands of violin builders doing it every day :P But then, they do it specifically for the purpose of making the plates easier to remove for maintenance. And if you size the endgrain with hide glue and let it dry before gluing the plate, it makes a fairly strong bond.

I've only constructed a couple of violins -- but mine had the traditional willow linings for the plate gluing surface. It does seem that the ease of disassemble is by design.
Author:  Imbler [ Mon Mar 23, 2015 4:11 pm ]
Post subject:  Re: Grain orientation of the end block.
So what is all this maintenance being done to the inside of violins? I was mentioning to a friend that they made violins more easy to disassemble because of working on them and he naturally asked, What are they doing in there?. I have to admit I was stumped!
Mike


DennisK wrote:
kencierp wrote:
If nothing else sanding and/or planing the blocks will be significantly easier and you will not be gluing the plates to end grain, which in my view is never a good idea.

Tell that to the thousands of violin builders doing it every day :P But then, they do it specifically for the purpose of making the plates easier to remove for maintenance. And if you size the endgrain with hide glue and let it dry before gluing the plate, it makes a fairly strong bond. But IME, guitars need as much bond strength as they can get at the tail block, because when the plates expand and contract with humidity change, the stress is focused there. If the seam is going to pop, that's where it happens, unless the tail block has a wider glue area than the linings, in which case it may pop to either side of the block.

I make the tail block parallel to the side grain, but have been considering going to a two ply block, with one layer perpendicular to the sides and one parallel. Should greatly increase split resistance, and still leave some side grain for the plates to glue to.

Split resistance is mainly important if you're going to use a tapered endpin, which is basically a splitting wedge, and has to be tight enough to stress the block or you risk having it fall out in low humidity. And if you drop the guitar on its tail, it's pretty much guaranteed to drive the pin in hard enough to split a parallel grain tail block.

I'm more inclined toward screw-in strap pins though, so that's why I haven't gone plywood already. Still might split if dropped on it, but at least it's not a pre-loaded wedge.
Author:  kencierp [ Mon Mar 23, 2015 4:24 pm ]
Post subject:  Re: Grain orientation of the end block.
I believe conceptually a first class violin is a "life time" investment -- so if a component needs repair or replacement for what ever reason it can be easily removed without the fear of causing more damage in the process, of course that is why hide glue is used as well.
Author:  wbergman [ Mon Mar 23, 2015 4:36 pm ]
Post subject:  Re: Grain orientation of the end block.
I have heard that as violins age, the changes in the wood (shrinkage??) cause changes that need to be compensated for by reworking them, which requires disassembly. This is in addition to the need for outright repairs.
Author:  meddlingfool [ Mon Mar 23, 2015 4:37 pm ]
Post subject:  Re: Grain orientation of the end block.
Fixing cracks for one, such as a sound post crack. One head to remove the neck and top to get in there to fix it, I believe...
Author:  Ed Haney [ Mon Mar 23, 2015 8:49 pm ]
Post subject:  Re: Grain orientation of the end block.
A mahogany block cut into two pieces and then glued back together with the grain turned 90 degrees. The block's piece with side grain presented to the top, back and side is glued to these 3, and it's thickness is slightly thicker than the linings to accommodate the curved guitar side. The block's piece with end grain presented to the top and back is facing the interior of the guitar and is angled on the top and bottom so that it is not touching the top or bottom. Bottom line: Thin, light, but very strong and with only side grain on all glued surfaces.
Author:  Haans [ Tue Mar 24, 2015 8:15 am ]
Post subject:  Re: Grain orientation of the end block.
I use baltic birch, and bevel the top and bottom to match the kerfing width. It's strong and easy.
Author:  kencierp [ Tue Mar 24, 2015 9:04 am ]
Post subject:  Re: Grain orientation of the end block.
We will be changing over to Baltic Birch -- likely 8 or 10 mm
Author:  Greg B [ Tue Mar 24, 2015 3:04 pm ]
Post subject:  Re: Grain orientation of the end block.
I've settled on parallel with the sides, with a small graft inlaid at 90 deg on the inside to help prevent splits. I've also stopped using the traditional mini splitting wedge end pins. They're best left to history IMO.

One thing that hasn't been mentioned is that if you do put the endblock with the grain direction vertical, it will have a tendency to telegraph through the top.
Author:  murrmac [ Tue Mar 24, 2015 6:03 pm ]
Post subject:  Re: Grain orientation of the end block.
......
Author:  wbergman [ Tue Mar 24, 2015 6:07 pm ]
Post subject:  Re: Grain orientation of the end block.
I know the original question was regarding the end block, but I have a personal example of telegraphing the block where the neck connects. I have a Marcelino Barbero classical guitar, which is a Japanese made guitar falsely represent by the distributor as Spanish. It is nevertheless considered a good guitar. But mine had the neck block (not a Spanish heel) glued in with vertical grain. When the entire guitar shrank, the neck block did not shrink as much. The fingerboard then raised over the body, requiring that the frets be pulled and the board planed. On the back of the guitar, the neck end cap that probably had originally been flush with the back shrank down and pulled the varnish loose just a little. So, the telegraphing is more than cosmetic.
Author:  SteveSmith [ Fri Mar 27, 2015 12:53 pm ]
Post subject:  Re: Grain orientation of the end block.
Haans wrote:
I use baltic birch, and bevel the top and bottom to match the kerfing width. It's strong and easy.


I started doing the same thing several guitars ago. I really like the idea that I don't have to worry about the block splitting.
Author:  mkellyvrod [ Fri Mar 27, 2015 12:58 pm ]
Post subject:  Re: Grain orientation of the end block.
There have been several discussions on the forum about this. As a result, like Steve and Haans, I now use baltic birch plywood, and have used it on my last four guitars.
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