Violin Sound Post Tool

[Diane Kauffmds]

Once again, I have a very old violin in my shop and the sound post has to be reset. I don't do this on a daily basis, so it can be an extraordinary frustrating 1-2 hours of work. There's a similar tool that you can buy for $89, but I've made mine a bit differently. I think this shape will be better than the 90° angle of the other tool.

Materials:

One 8", 5mm OD brass tube, with 3mm ID
One section of a 6mm OD brass tube, with 5mm ID
Waxed dental floss

Total investment: $10

I bent the 5mm tube with my fretwire bender, so that I wouldn't
collapse the tube. I used a 1" piece of the 6mm tube, cut open as the post support. 1 bent each end of the 5mm tube into gentle opposing curves and tested the curvature with the violin until I was satisfied.

The 6mm tube is very thin and easy to cut open with a set of medical tape scissors. I opened the tube, and drilled a 5mm hole to match the handle. I inserted the 5mm tube through the hole, and I used an old reamer, gently flared the end. This made the 1" section captive. I clamped the handle with the working end hanging down and straight, and soldered the two pieces. I cleaned up the 1" section to smooth it, making it safe to use.

The dental floss can be threaded using an old discarded #1 guitar string, or just simply folded and just pushed through. The 1" tube section keeps the post straight, the floss keeps it from dropping until in place. I just drop the floss, pull out the tool, then grab 1 end of the floss to pull it out of the violin.

What took 1+ hours, I did in 5 minutes.

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[Kevin Sjostrand]

Diane
As you can imagine this interests me. I have a couple different tools for setting the post and it can be a frustrating endeavor for sure.
So how is the loop of floss released to pull it out once the post is set if it's around the post and there's no clearance at either end of the post to do so?

[Diane Kauffmds]

Hi Kevin,

I take a long length of waxed tape or floss, fold it in half creating a loop, feeding it through the long tube. You can go from either end, but I started from the handle end, pushing the loop through. This leaves a loop of floss at the working end.

Put your post into the holder in the loop, and pull the ends taut to hold the post. After setting, release the ends and pull the tool away. The 2 ends will be sticking out of the f-hole. Grab only 1 end and pull the floss out. It'll just slip away.

I set the post in the violin. I took me 2 tries, but in all, just 5 minutes to set. It worked like a charm. I've got the materials sitting here. I'll send you one. Just let me know.

[Kevin Sjostrand]

sure how could I resist. Thank you dear.

I've spent many minutes.....many puting posts in

[Diane Kauffmds]

sure how could I resist. Thank you dear.

I've spent many minutes.....many puting posts in

Tell me about it!

[rcnewcomb]

Back in the 1970s I worked in a music store. We had a scissors style sound post setter that had the curves almost exactly like the tool you designed. It was very easy to use. It may have been a shop-made tool since I have been unable to find another one.

[Diane Kauffmds]

Back in the 1970s I worked in a music store. We had a scissors style sound post setter that had the curves almost exactly like the tool you designed. It was very easy to use. It may have been a shop-made tool since I have been unable to find another one.

Randy if you need one, just let me know.