Thank you for sharing this crack clamp technique

[welshman]

I just wanted to thank who ever suggested this clamping technique here on the board in the past, it stayed in my memory enough to try it on this difficult crack repair on a cello.

 

Took a little time to make the PVC spring clamps and get the engineering of the clamp surfaces right but they worked like a charm and did the job nicely, was able to check the crack alignment as i went and easy to see what was happening.

 

ths crack was just close enough to the bassbar to be a problem but not close enough to remove the bassbar, I will get cleats in without the expense of a new bassbar (a budget concern of the owner) and clamping from the exterior produced a flat/depressed area in the arching along the crack. clamping from the interior with the pressure as close to the interior arch produced a tight repair and realigned the arching on the exterior.

 

all in all a neat idea (the little cleats were left over plugs from my furniture design days, used to hide screw holes)

I used ten spring clamps in all, spaced out along the crack and the clamps made from two and a half inch pvc pipe, the clamp surfaces shaped with half round file, and small groove made with a chainsaw sharpening file and a flat area created with a sanding block.

 

thanks for whoever posted this idea before.

 

reese

 

 

[sawdust]

Hi Reese,

 

You need to thank Oded  Kishony for this wonderfully simple clamping method.

 

 

[Oded Kishony]

You're welcome. Glad they work for you.

To the best of my knowledge the person who developed the original concept of 'tower clamps' was Peter Moes.

But I did come up with this particular wrinkle to the process.

I no longer use these clamps except for gluing linings (see below)

I now use these shop made clamps

you can buy these type of knurled screws in light weight plastic for under 15 cents each and make a clamp for under $0.50 (minus labor)

Oded

[BarryD]

Thanks for great ideas!

[welshman]

I had originally thought of try to make something like those but the space next to the bassbar precluded something shaped like that , the ring clamps where the perfect solution to this particular problem.

 

A big thank you for posting your solution Oded

 

Reese

 

I need a new picture, my girls are 13 and 10 years old now and I am feeling my age