Michael_Molnar

I choose the arch height that sounds good. I don’t have the time to wait for a violin to stretch.

Yes. About a year.

Right. When chemically staining do not nuke the wood with high concentrations. Less is more because it is controllable. Excess oxidants can be hygroscopic (attract water) which means that in high humidity they reactivate and degrade the wood structure over time.

Wow. Thanks. You made this old man happy.

There is no golden rule that spruce and maple must be treated the same.

Armchair theories always sound great until they are brought into the shop where they become impractical.

Marty, have you made anything using this theory?

How do I determine a targeted impedance? Which plate do I select?

Go down the list of just the prominent Cremonese makers for starters.

My response to Darnton referred to the timing of his post with Don's email. Nothing more. We all know that Darnton and other prominent makers, have advocated for years the importance of dynamic feedback from playing a violin. Nevertheless, Don showed us the incontrovertible scientific evidence.

What did you guys use to cut the logs?

Our friend, Dale, at WoodFinishing Enterprises makes and sells good thickened linseed oil.

Don is ahead of you. He told me this exactly in an earlier email. I am grateful that Don let me look over his shoulder. His data reinforced my intuition that we were doing the wrong analysis because I wasn’t seeing repeatable results. His data graphically show that. However, the big issue according to Don is how to do this dynamically with reliable feedback and controls. I now let the players and audience do the evaluations. BTW, all is not lost. Don has convinced me how important arching and wood are. There is a family of arching systems that gives nice results. And wood processing works too.

After discussing this with Don and now seeing Davide's post, I concur. M5 will be a guide, not an end result. We can rule out the extremes, nevertheless. I am using a new arching and hope it will produce a better violin. Time will tell.

I prefer hide glue.

I like Davide’s theory. I recall having a plate with a hidden crack probably from the trauma of the falling tree I spotted the hairline crack while flexing the plate. Bummer.

This sounds reasonable. Thanks.

The circles inscribed on the form indicates the rib taper.

Hmm. That could be it. The lamps put out a lot of UV and run cool, so it may not be IR. It just might be the TOTAL energy across the spectrum. In any case, a revolving carousel for evening out the incident energy would not hurt.

Right, David, However, the spectrum of these lamps extends farther into the UV into the realm of UVC or nearly so to stimulate better production of a certain desirable plant chemical. I still think that the lack of air movement and rotation of the violin fail to even out the surface temperature. Local hotspots will lead to very dry areas.

What is the total wattage of the lamps? How far are they from the violin? I suspect that your violins are getting a “sunburn” as it were.

OK, but why would I want to switch to rice glue? How is it better than hide glue?

Those pins are not necessarily oval. The pin under the fingerboard is viewed obliquely. The other is damaged and split giving again an illusion of being oval. Do the math if you insist that the pins were squeezed by contracting spruce to match this illusion. The spruce plate would need to shrink to a similar oval to where it no longer fits the rib garland.

Marilyn Wallin does this. IIRC, it is 30, 32, 32, 31. It does look nice.

After I bring down the overall rib stock thickness to 1.1+ mm thickness on a reciprocating spindle sander, I scrape away the sanding marks with a disposable single edge razor. The razor blade acts like a block plane with a flat sharp straight up blade. Just hold the stock up to a light to see the marks.