Latest in progress from AHG

[AcornHouse]

Sides have been cut to size and thicknesses down to 1.8mm; ready for the bending iron. (I wiped a couple of spots with alcohol to bring out the figure.) Typical flamenco guitars use either cypress (flamenco blanca) or rosewood (flamenco negra) for their back and sides, but I opted for a less usual figured maple (which does have some precedence); not just for its looks, but for its dry, sharp, powerful sound, which I think compliments the flamenco ideal.

 

[Nuuska]

Chris, I hope you don't mind if I add this info about the Spanish Heel which was an invention of Antonio Torres.

The Spanish Heel: What It Is and Its Benefits

The Spanish heel is a system of guitar making and as you can tell, it’s characteristic in Spain and applied to all Spanish guitars that are manufactured here. The Spanish heel system it’s a simple …

blog.guitarfromspain.com

Ralf

Thank you

I just peeked into my Carmelo Gonzales - to find out that it has spanish heel - although inside is squared instead of round. I bought it used in Zürich 1971 - he still makes guitars and was happy to see pictures of my example of a set of guitars he built for swiss students back then.

 

[AcornHouse]

First side is bent. No problems, bent nice and evenly, just took it slow and steady. I’ll try to post a video in a day or two showing my technique on the other side using my homemade bending iron setup. (Instagram followers may get a sneak peek sooner, hint, hint.)

 

[BradHK]

I love watching the details of each step! Thanks for Posting the continued progress and I am amazed at your skills and knowledge! A quick question on the Spanish Heel - obviously this would make a neck reset impossible without taking apart the entire guitar. Is it the lower tension from the nylon strings, the construction method of the Spanish heel, a combination of both, or something else I am missing that makes a neck reset not a concern on classical guitars with Spanish Heels?

I now can’t wait to get home and look inside my classical guitar to see if it has a Spanish Heel and how it is shaped!

 

[AcornHouse]

I love watching the details of each step! Thanks for Posting the continued progress and I am amazed at your skills and knowledge! A quick question on the Spanish Heel - obviously this would make a neck reset impossible without taking apart the entire guitar. Is it the lower tension from the nylon strings, the construction method of the Spanish heel, a combination of both, or something else I am missing that makes a neck reset not a concern on classical guitars with Spanish Heels?

I now can’t wait to get home and look inside my classical guitar to see if it has a Spanish Heel and how it is shaped!

Partly its the lesser string tension with nylon strings, partly it’s because of the foot extension(s) on the inside that resist the neck from changing neck angle, and partly because of the guitar being built around the neck. With the inside part being part of the outside part, there is no joint that can shift over time; it’s the same piece of wood.

 

[AcornHouse]

Here’s the shorter Instagram video. I had everything all set up and when the pipe was hot enough I started recording the long video. And forgot to turn on the big photo light box! So this clip is from the latter stages, working on the lower bout bend, WITH the light.

The bending pipe is my own construction consisting of a 2” galvanized pipe, like you’d find on chain link fences, with an electric barbecue starter wired to a rheostat mounted on some unusable (for woodworking) block of wood with some strapping to hold the pipe.

Christopher Kenney on Instagram: "Bending the curly maple sides on the hot pipe."

4 likes, 0 comments - acornhouseguitars on September 8, 2022: "Bending the curly maple sides on the hot pipe.".

www.instagram.com

(And the same on FB.)

 

[AcornHouse]

Here’s the start of the bending session with just the room lighting. A little narration and lots of steam.

 

[GGJaguar]

Do you find one species of wood easier to bend than others?

 

[AcornHouse]

Do you find one species of wood easier to bend than others?

Walnut is probably one of the easiest woods to bend. I haven’t yet built with the set I have, but ziricote has the reputation for being one of the hardest, prone to cracking.

Much of it is due to the cut of the wood. Quartersawn wood running true and straight will always give you an easier time. The worst experience I’ve had is bending ebony bindings. I had to get a whole extra set because it would keep cracking along the grain which wasn’t running parallel to the length. And, of course, being ebony, you couldn’t really see the grain until it started splitting.

 

[AcornHouse]

I have two bridge blank options, at least in the rosewood family. (Ebony would be far too heavy and dense for nylon strings. It needs the higher tension and pick velocity of a steel string.) One is East Indian, the bottom one, Brazilian. Aside from their marked visual differences, the Braz. is far less dense, with 1068.11g per mm3 vs 1380.04g per mm3 as measured from these blanks by me. (Different pieces of the same species can vary wildly. I had some sinker Honduran mahogany that was far heavier and dense than any Honduran mahogany of used before or since.)

In a flamenco guitar, where an incredible lightness of being is more important than in almost any other type of guitar, this is important.

 

[Default]

One of many factors that never occurred to me.

 

[fronobulax]

In a flamenco guitar, where an incredible lightness of being is more important than in almost any other type of guitar, this is important.

Does that mean you're going with the less dense Braz?

 

[AcornHouse]

Does that mean you're going with the less dense Braz?

Yes.

 

[Nuuska]

Maybe a typo there ?

with 1068.11g per mm3 vs 1380.04g per mm3 would be equal or heavier than Les Paul or close to black hole @ 5 million metric tons per gallon . . .

dm3 = a liter

 

[AcornHouse]

Maybe a typo there ?

with 1068.11g per mm3 vs 1380.04g per mm3 would be equal or heavier than Les Paul or close to black hole @ 5 million metric tons per gallon . . .

dm3 = a liter

Ok, possibly. I multiplied the dimensions in the blank in mm and divided that by the weight of the blanks in g. So whatever that works out to.

Here‘s the raw data:

EIR
12.2 x 50.8 x 191.5 mm
86g

Braz
12.6 x 36.3 x 198.5 mm
85g

 

[Nuuska]

OK

So it is EIR 1380,4mm3 / g = 724g/dm3

BRAZ 1068,11mm3 / g = 936g/dm3

You have volume/weight instead of weight/volume.

 

[davismanLV]

The funny thing is I immediately went for the Brazilian just for looks but thought, no too heavy for this type of guitar. Then I reread your post and so now all is aligned in the Galaxy!!!

 

[AcornHouse]

But, there is another factor to consider. The tonal impact. Braz. tends to let the higher frequencies ring more; EIR can dampen them (but less than ebony.) we will discuss.

 

[Opsimath]

Wow. How did you come to know all that you know?

 

[AcornHouse]

Wow. How did you come to know all that you know?

Research comes easy to an academic. Many luthier books many online resources. And the more you work with the wood, the more you understand (or think you understand) about it.