Antonio Torres Jurado

[Tod Gilding]

I have been reading a bit about luthiers from days gone by, such as Torres,one thing that I am unable to find is How did they control Humidity in their shops ? on the NSW north coast, without electricity, I wouldn't have been able to do any cross grain glueing for at least 12months.
Can anyone tell me how they did it ?

[charangohabsburg]

Hi Tod,

José Romanillos wrote in his book Antonio de Torres, Guitar Maker - His Work an Life that Torres seems to have made use of the daily humidity fluctuations in Almería; at night the wind changed and brought drier air down from the mountains (while at day the wind brings in moisture laden air from the sea. It is also told that Torres read the actual RH with a shop built hygrometer which seems to have been a wooden (cross grain?) strip between two fixed points which would bow more or less, according to RH (if I got the description right). Romanillos writes that for some operations Torres used to "burn his midnight oil", and we believe this was because he was waiting for the correct RH.

In the pictures below you can see the "bi-wood" strip I use as hygrometer (version 1.0 and 1.1) and it reacts really fast (within less than two minutes when I open a window on a rainy autumn day!

<= v 1.0 _____ v 1.1 =>

In February 2012 I started to measure RH with a psychrometer and record the absolute values the wooden hygrometer indicates, just to know how consistent it is through the years.

[Tod Gilding]

Hi Markus Thanks for that information, I have seen your laminated stick Hygrometer in another post,great idea.

but if the night air was all he had to work with it doesn't leave a lot of time for the wood to dry to where I would like the moisture content to be before sunrise and then the wood would start absorb again.

I was thinking that he must have had some sort of dry box to store the wood during the day, possibly he had an oven running at low temperature but high enough to dry the air inside during the day before bringing it out at night to glue up.

What he did we may never really know, but his instruments have stood the test of time.

[charangohabsburg]

I never heard or read that those luthiers had such a thing like dry boxes, and I can not see a reason why they should have had such things. They simply made every assembly step at the same RH. Try to do this when pulling a piece of wood out of a drying box to every time a different RH! The wood reacts within minutes, and veneers for tops and backs will stabilize within an hour or so (although some very dense woods may take between two and four hours requiring probably to assemble them only at certain months of the year). In any case, when the wind changed again to bring in humid air from the sea the glue had already set a few hours before, and if no further assembly steps were made until Don Antonio again measured a suitable RH nothing could go wrong.

[Tod Gilding]

I see Markus, That must have been a pain in the Ar%e , I suppose we don't realise how good we have it.

[charangohabsburg]

Not sure Tod. If you are talking a of a fully climate controlled shed which Torres did not have I agree, but a dry box can turn out to be a box of worms. I also think that there are more difficult climates than the one in Almería where RH changes are almost every day the same (in a given period of the year). Of course, Torres had to stay up until after midnight, but right now I am also staying up after midnight - sitting in front of the computer screen! Every epoch has its own PITAs, hahaha!

[Nick Payne]

I've read that Fleta guitars commonly have problems in conditions of low humidity, as Ignacio Fleta built in conditions of reasonably high humidity in Barcelona, and didn't have/use any means of humidity control.