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Hi

I´m preparing my first steelstring guitar. an OM sized guitar with bolt on neck (cumpiano style). I´ve made many Spanish guitars but they were all with a Spanish heel so this is new to me.

When reading books and online, its said that the headblock should have horisontal grain or in other words the same grain direction as the sides.
I´ve just received the woods I ordered from Madinter and the headblocks are NOT like that. One is vertical grained and another is what I will call diagonal grain. I´m sure they have been cut with the idea og getting as much material out of a piece of wood. Also, here in Spain, when building Spanish heel, this with grain direction on the heel/block is not considered important.

So whats the verdict? I´m pretty sure its not worth the energy sending the pieces back. I dont think they´ll have anything better. Can I build with what I have or should I order blocks from the US with "correct" grain?

Assuming it's mahogany, grain orientation in terms of quartersawn/flatsawn is largely irrelevant since it expands nearly equally in both directions.

If you mean vertical as in the plates will be glued to endgrain, that's a little more iffy. But those tend to be fairly large glue surfaces, so especially if you saturate it with hide glue first, and then glue, it'll probably be fine. After all, violins use blocks aligned that way because it's easier to separate the joint for repairs... and you don't see them exploding all the time.

Anders: The head block takes a lot of stress. I would not use a block that does not run the same way as the sides. Two reasons in my mind, it's nice to have expansion and contraction some what equal and secondly I think it's stronger. Some folks say a crack in the sides can migrate to the block. I put two 1/4" dowels running vertical to reinforce.
Tom

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A person who has never made a mistake has never made anything!!!

I like to go with the sides myself especially because that means that planing the flat grain block to fit the back will be much easier then if you have end grain.

I've only done one Spanish heel, but the one I did most certainly did not have the soundboard glued to endgrain.
That would have to be one giant tree!

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Always have plenty of sandpaper; it's rough out there!

Thanks for you replys

Its difficult to explain and my English is reaching its limits here. And the use of vertical/horisontal might be confusing.

The block, with what I call vertical grain, that they´ve send me, will have the grain running 90 degrees to that of the sides and the endgrain towards the sides (does this make sense?)
This means that since I´ll be stacking the heel with a quatersawn neckblank, the grain of the heel and the endblock will be the same. Is that good, ok or bad?
The other block, will also have endgrain towards the sides, but the grain is running diagonal.

When I build Spanish heel, the soundboard is never glued to endgrain but if I stack the heel, the grain normally ends up like the block they´ve send me for an acoustic guitar. But there´s a difference between Spanish heel and "American construction". In traditional Spanish construction, the sides are not glued to the heel/block.

For what it's worth, I have over 150 instruments built, going back to 1970. All (steel strings) have had the end block grain running vertically (at 90 degrees to the sides). Early builds were dovetails, vast majority since 1996 were bolt on (Cumpiano style) and NONE have ever failed/cracked or had the top or back separate from the "end grain" glue joint. I cut my own blocks and always maintain a straight grain orientation in the final cut blocks.
Hope that helps your peace of mind regarding end blocks.

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Hank Mauel

Thanks a lot. Now i will just relax o maybe i'll worry about something else.
After building many flamenco guitars, this is all different and strange, so i'll most probably end up with a lot more questions in the comming weeks.

Hi Anders,
Normal practice is to have the headblock oriented in the same manner as you would for a tailblock.
You have sidegrain for gluing to the soundboard,back and sides rather than endgrain.


Definitely not the same orientation as in a spanish heel

What sort of neck joint are you using?

The reason for the grain following the direction of the sides is so that all the gluing surfaces are mated to long grain rather than endgrain, which arguably results in a stronger glue joint. How much that matters in a guitar is open to debate. Does it really matter if the top and back are glued to endgrain? I rather think it does, as the surface area is also reduced.
I'm not convinced that a guitar will completely fail if the orientation is not correct, but I've never bothered to try it that way.

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Old growth, shmold growth!

I know that sidegrain on all gluing surfaces is standard on acoustic guitars and that on violins, gluing the plates to end grain es standar.

But the blocks that madinter send me, are with endgrain towards the sides. Since I´m not building with a cutaway, the sides will be hold by the engrain gluing surface, the bindings, and the bolted on neck.
Thats what worried me.

i try to sprinkle a mixture of black wild rice and 6 row wheat on my head blocks, while the laquer is wet. another guy i know toasts barley and cracks it slightly in a mill before applying. some other grains i heard guys using on headblocks are millet and malted quinoa. hope this helps

That would be a VERY unusual way to do it
Most people do it with the grain parallel to the sides, some with it running from top to back, but I have never heard of anyone doing it that way.
I can see a number of problems with doing it that way

So please tell me which problems you see.

Ok
I am presuming you have a block about 75x 35x 90 with the 90x75 area endgrain
- gluing to endgrain is generally less effective
- the block will be weaker in resisting neck pull
- with that large area of endgrain it will be prone to warping and splitting particularly when you glue it to the sides with water based glue

It may very well be sufficient, but it would not be optimal
If I did not have large enough material, I would rather build up a block from smaller pieces than use that endgrain block.

The weakest part of this arrangement (I would think, since you are using bolts apparently) is the gluing of the sides to endgrain. On the classical/flamenca's, the sides are either in a slot or wedged in - sometimes not even glued. But here, the glue surface is everything. The joint takes a lot more stress, too.

If you wanted to use material on hand, I think you'd be better off just cutting a section off of a regular neck blank equal to the body depth of the guitar, but then that leaves you with end grain to glue the top and back to. Hmmm...

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Jim Kirby
kirby@udel.edu

I´ve decided that I wont use these two blocks from madinter.
I have some very nice Khaya mahogany. Absolutely best quality with a very fine grain . This I will use for my first steelstring guitar. I have enough for neck, heel , headblock and endblock and everything with the grain running in the correct directions.

Thanks for your advices.

In case anyone is interested.

I made a drawing of a correct headblock and one that was like Madinter had cut. Telling what I wanted.

They were kind, agreed that it was their fault and told me they would send me 2 other blocks which I have received today..

The drawings were pretty clear (No endgrain against sides, top and back) so I was surprised to see that the two blocks were cut with the endgrain towards the top and back... (like on a violin.)
So I called them and was told that the guy cutting the wood will be there. So lets see what happens.