View previous topic :: View next topic |
Author |
Message |
kubasa Member
Joined: 13 Sep 2007 Posts: 212
|
Posted: Fri Sep 09, 2016 11:00 pm Post subject: Too soft of a top? |
|
|
I've been meaning to ask this question all summer but between work and health issues, I haven't gotten around to it.
Last summer I finished a violin that I was very pleased with until I put the strings on it. It didn't sound the greatest. I played it for a month or so and it sounded even worse. I move the sound post around, cut a new sound post and even cut a new bridge. Nothing helped so in frustration I put it away in my storage cabinet and left it there. Mid-winter, I pulled it out and gave it one more try and to my surprise it sounded pretty good. I wondered if the humidity had affected it somehow so I put it in another room without a humidifier and got down to around 25% humidity and it sounded even better! Now keeping an instrument dry like that is not the best idea nor is it possible all the time.
Any ideas for a fix? Throw the top plate out and start over?
James |
|
Back to top |
|
|
Michael Darnton Moderator
Joined: 23 Mar 2007 Posts: 1281 Location: Chicago
|
Posted: Sat Sep 10, 2016 11:07 am Post subject: |
|
|
For a start, I'd try popping the seams in the upper and lower bouts of the top, and regluing them during some season when it sounds bad, not while it's sounding good. If you put it together in strange weather It might be stressing too much at other times, and want the stress removed. Don't bother with the blocks or the c-bouts--those probably aren't the problem. _________________ new blog at my site! http://darntonviolins.com/blog
my work sites: http://darntonviolins.com and http://darntonhersh.com |
|
Back to top |
|
|
kubasa Member
Joined: 13 Sep 2007 Posts: 212
|
Posted: Sun Sep 11, 2016 12:00 am Post subject: |
|
|
Thank you Michael. When I glued the top on, I know the humidity was low in my workshop because it was late winter/early spring. That makes perfect sense, plus it will give me practise loosening the tops.
James |
|
Back to top |
|
|
Michael Darnton Moderator
Joined: 23 Mar 2007 Posts: 1281 Location: Chicago
|
Posted: Sun Sep 11, 2016 9:34 am Post subject: |
|
|
By the way, it's not uncommon for an instrument to sound terrible initially and then come together later, permanently. One of my best sounding violins sounded so bad at the start that I put it away and forgot it for two years. When I found it and tried it, it had changed so much that I decided to keep it, and I still have it.
So the change may well be permanent. I certainly wouldn't try to fix it until I was sure it was broken. :-) _________________ new blog at my site! http://darntonviolins.com/blog
my work sites: http://darntonviolins.com and http://darntonhersh.com |
|
Back to top |
|
|
kubasa Member
Joined: 13 Sep 2007 Posts: 212
|
Posted: Sun Sep 11, 2016 11:56 am Post subject: |
|
|
That's a good point. There's no hurry on my part so another year or two to decide won't hurt.
This dovetails into the whole idea of playing in an instrument. I know that it helps but I've heard of instruments like your example that sounded better just sitting with no playing in. My Dad had a guitar that sounded terrible. It sat in a closet for 20 years and today it sounds absolutely amazing. It must be that "coming together" process like you mention. |
|
Back to top |
|
|
kubasa Member
Joined: 13 Sep 2007 Posts: 212
|
Posted: Sun Sep 11, 2016 6:37 pm Post subject: |
|
|
As the day went on I was thinking more about the wood settling and coming together. i thought of last winter when I was making spoons out of walnut branches for Christmas gifts. The branches had been drying for about 2 years and seemed dry but when I cut some of the branches in half on my bandsaw, the wood bent immediately. In fact, the arching was so strong that I couldn't put the two halves back together. That really surprised me. Obviously there were stresses inside of the wood just waiting to get out. Makes me wonder how long I would have had to let the branches set before that stress would have disappeared....I'm sure some of that exists in violin making as well.[/i] |
|
Back to top |
|
|
Michael Darnton Moderator
Joined: 23 Mar 2007 Posts: 1281 Location: Chicago
|
Posted: Sun Sep 11, 2016 6:49 pm Post subject: |
|
|
You might be describing case hardening. That's when wood dries too quickly, and the outside is fixed in size as a crust over a wet (still expanded) core. Then the wood inside gradually dries and shrinks, becoming smaller than the shell around it but unable to do anything about it. As soon as one side of the inside is released from its shell by the saw, the shrunken internal wood takes over on that side and pulls the wood into a curve around the part that was inside. In modern drying this is controlled by gradually reducing the humidity of the kiln just a bit ahead of the wood's moisture content, so that the inside and outside stay similar in moisture content and dry at the same rate.
At the bottom, here:
http://www.hobbithouseinc.com/personal/woodpics/_lumber%20defects.htm
. _________________ new blog at my site! http://darntonviolins.com/blog
my work sites: http://darntonviolins.com and http://darntonhersh.com |
|
Back to top |
|
|
kubasa Member
Joined: 13 Sep 2007 Posts: 212
|
Posted: Sun Sep 11, 2016 11:42 pm Post subject: |
|
|
Thank you for that link. Towards the bottom on the right they show a reverse casehardened. That shows it perfectly. I don't know why the arching or bending surprised me on these walnut branches. I spent my years as a kid splitting a lot of wood for our stove and saw a lot of weird grain, knots and other oddities. I guess that's why I enjoy working with wood so much - there's always something new to learn. I miss having a wood stove. It was nice heat but I don't think my back would handle all the work that goes with it! |
|
Back to top |
|
|
|