Banjo Hangout Logo
Banjo Hangout Logo

Premier Sponsors

Fiddle Lovers Online

Discussion Forum

 All Forums
 Other Fiddle-Related Topics
 Fiddle Building, Setup, and Repair
 ARCHIVED TOPIC: Sound Post Crack in Top..suggestions on how to fix

Please note this is an archived topic, so it is locked and unable to be replied to. You may, however, start a new topic and refer to this topic with a link:

fordraiders - Posted - 10/28/2008:  06:55:39

Well, Hopefully not a repeat question.

I have a fiddle I picked up in a Antique store.
Cleaning it and getting my hands wet on repairing.
This is the first one I have had that looks like a sound post crack on the top and and under side plate.
Running the grain...

Without taking it to a Luthier...Can anyone suggest or give me links on experience in fixing these cracks...or is the top doomed .

My weird thinking is to cleat before the crack and after...
I have to take the top off to reset it properly.


David Powell

voodoo - Posted - 10/28/2008:  07:48:34

Take off top. Clean crack. Glue crack flush with very hot fresh strong hide glue.

Support top outside down in a fitted holder to avoid opening crack. Carve out hollow where soundpost goes, very smooth, almost to outside surface where post will it. Do not touch. About size of a quarter.

Carve spruce piece with grain angled from the top a bit to fit in hollow exactly. Almost sticks in when fitted well.

Prime both surfaces with dilute glue, then heat both surfaces, spread strong hide glue, and lightly clamp. Let cure for a few days.

Carve graduation into the patch.

Friendsville, TN

fordraiders - Posted - 10/28/2008:  08:00:36

Wow....Very nice example...Thanks....voodoo...appreciate the help.. !
Are these in steps 1-6 or just different ways to repair ?
Thanks so much !

David Powell

voodoo - Posted - 10/28/2008:  08:01:24

Steps. Standard process.
Friendsville, TN

FiddleDoug - Posted - 10/28/2008:  13:45:40

The "fitted holder" that's mentioned usually means a plaster cast of the front (or back). The area to be patched gets carved down to about 1/2 mm thick, and if the area isn't totally supported it's real easy to push a tool right through the front (a bad thing). This repair is not considered a job for an amateur!

Doug Wall

fordraiders - Posted - 10/28/2008:  14:55:39

Well that's what I like about the work..Challenging and skillful .. Practice makes perfect.
Plaster molds....Self made or store bought ?

David Powell

voodoo - Posted - 10/28/2008:  16:07:04

Carved, plaster, or whatever. I have used stiff foam to brace the area worked on, but that's just a field expedient.

This isn't an impossible job, but requires some tool skills. I wouldn't think of it as a starting out project. I prefer not to do it myself. Most folks seem to think I should be able to fix their violin with the soundpost crack in about 2 days. Isn't going to happen!
Friendsville, TN

fordraiders - Posted - 10/28/2008:  18:04:46

Stiff foam sounds good...

I have several books....stroebel. etc,,,..most of the repair violin books..

Most of them do not address sound post cracks...
I have a local luthier...She is very good.
I plan on asking alot of questions and watching her do one.....

Like the foam idea !

I just moved and getting my shop back in order...

Thanks again all

David Powell

superdave2112 - Posted - 10/28/2008:  19:41:29

Originally posted by fordraiders

Stiff foam sounds good...

I have several books....stroebel. etc,,,..most of the repair violin books..

Most of them do not address sound post cracks...

Violin Making: As It Was and Is.... By Ed Heron-Allen

Chapter 23 - Repairs

Pages 309 (at the bottom), 310, and 311. Section is called "Crack in Back or Belly resulting from Pressure of Sound Post."

There you go!

Always most sincerely yours,

David Loudenback

Edited by - superdave2112 on 10/28/2008 19:47:07

fordraiders - Posted - 10/28/2008:  20:36:45

Thanks Dave...!

I was also reading my "An Encyclopedia of the Violin" Alberto Bachman... It's a turn of the century (20th)...but contains good information on making a violin ad has specific measurements.

but nothing about repairs.

I found the fiddle in n old case in Buckhannon, WV...
I saw it 3 years ago...It was still there in Oct 5th.
Still cleaning the dirt off...
Finding a beautiful maple finish...
The top plate is actually in good condition.

The only visible crack appears to be a crack starting at the sound post...

Thanks again...will do some reading !

David Powell

pick1 - Posted - 10/29/2008:  13:13:07

I can't think of a way to make these repairs without taking the top off. Repairing it is worth a try providing someone has not tried this repair before using something other than hide glue. Cleats should be enough support it but the soundpost may have to be moved slightly. My idea would be to work some glue into the crack from the underside and clamp 5 or 6 cleats the entire length of the crack. The upside to this is when repaired, the finish will match. Making a new top would be the safe answer.

voodoo - Posted - 10/29/2008:  14:53:22

No. Cleats won't do it. Needs a patch of some kind. Just cleating might work - so long as you put the cleats on the outside.
Friendsville, TN

fordraiders - Posted - 10/29/2008:  15:52:11

Most of the books I have read. say to patch...
Found a website with neat graphics and steps ...

and going to purchase the book suggested by voodoo...

Appreciate the responses all...

I'm still cleaning the outside a bit then, yes going to take the top offf... Its 1/2 off anyway...I'll post a pic as soon as I can take a picture...

David Powell

fordraiders - Posted - 10/29/2008:  15:53:57

By the way, I did take a light and looked around inside... The post is at alomst a 30deg angle...and clearly to long... I took it out...

David Powell

superdave2112 - Posted - 10/29/2008:  21:38:25

Steve's right on. No way to the cleats in a pressure area, unless you want to see the crack open up again. You have to have a fresh, no crack surface to spread the load.

Steve, I love your work with the band Journey, by the way. Great voice. I bet you get that a lot?

Always most sincerely yours,

David Loudenback

voodoo - Posted - 10/30/2008:  04:28:06

I have seen an effective repair with a maple veneer on the outside, glued with what looked like epoxy and colored with a sharpie. That's on the tension side and supports the bridge well. But it was fairly hideous! That's the problem with cleats - the outside is under tension. I've also seen thicker maple patches on the inside that will probably work for quite a while. But it isn't really the way to do it. Cheaper.
Friendsville, TN

fordraiders - Posted - 10/30/2008:  05:28:59

Dave, Voodoo, WHere do you get this nice piece of maple or spruce shaped like an oval...per my previous link above.. ?

It looks like they have a piece of spruce or maple block...?

Found a website with neat graphics and steps ...

Thanks for the good chat !

d powell

David Powell

fordraiders - Posted - 10/30/2008:  05:31:50

I emailed Brian at roche violin...Will let you know when I get a response also !
d powell

David Powell

voodoo - Posted - 10/30/2008:  05:59:17

Can make a template oval, no biggie. Usually drafting templates have nice ovals, or construct one with a compass.
Friendsville, TN

Hangout Network Help

View All Topics  |  View Categories