Let's talk about Ground

[David Beard]

7 minutes ago, JacksonMaberry said:

~10 microns of oil penetration is about perfect. 

I will make bold to suggest that besides simple oil, balsaams and mixer of various combinations of oil, balsaams, resins, cooked varnish can have very similarly satisfying results.    Provided, the mixture has a creeping wetness nature the way oil does.

I will also suggest that fine levigated pigment can be added.  The capillary action will pull the color into the wood structure in a transparent way, highlighting the wood structure in a light angle dependent way.

[sospiri]

1 hour ago, JacksonMaberry said:

~10 microns of oil penetration is about perfect. 

Look at the photo. What do you see?

 

1 hour ago, uncle duke said:

How would sospiri go about measuring for microns?

By trying to reproduce what The Paris researchers suggest is there in that photograph. 

The more important measurement is volume. How much oil and how to apply it.

Do tiny amounts filter down through capillary action? If so, what does this do structurally and tonally?

And many other questions. 

 

[JacksonMaberry]

1 hour ago, David Beard said:

I will make bold to suggest that besides simple oil, balsaams and mixer of various combinations of oil, balsaams, resins, cooked varnish can have very similarly satisfying results.    Provided, the mixture has a creeping wetness nature the way oil does.

I will also suggest that fine levigated pigment can be added.  The capillary action will pull the color into the wood structure in a transparent way, highlighting the wood structure in a light angle dependent way.

Agreed.

[JacksonMaberry]

6 minutes ago, sospiri said:

Look at the photo. What do you see?

 

Penetration of between 50 and 100 microns, or thereabouts. Seems fine to me.

[uncle duke]

53 minutes ago, sospiri said:

Do tiny amounts filter down through capillary action? If so, what does this do structurally and tonally?

Probably.

I do not know - what I've done is read, learned, maybe observed, and probably read again to just don't use linseed oil for grounding/sealing. 

So I have never used linseed oil for sealing/grounding.  It may be perfectly o.k. to do that or just simply o.k.. 

[joerobson]

On the subject of acoustics of the ground, I will obviously defer to real violin makers  My experience is only anecdotal.

On appearance, however, there are many factors to be examined and evaluated.

I prefer the "compared to what" approach. 

In these photos of a dresser I made 30 years ago [I had a commission for 3 so I built 4] the linseed oil finish was a very viscous  [like honey from the refrigerator] oil polished on 3 times over 3 days.  It has retained its sheen and protective qualities to this point.  It has lost the crisp appearance and detail of the wood which it had in the beginning.  This is sugar maple so it is harder than the maple used for violins.  The capillary action of the wood has drawn out the oil and muted the detail.

The other is a detail of the Balsam Ground at 20 years.

Each method we discuss will have its up and down sides.

on we go,

Joe

 

 

 

[JacksonMaberry]

49 minutes ago, joerobson said:

On the subject of acoustics of the ground, I will obviously defer to real violin makers  My experience is only anecdotal.

On appearance, however, there are many factors to be examined and evaluated.

I prefer the "compared to what" approach. 

In these photos of a dresser I made 30 years ago [I had a commission for 3 so I built 4] the linseed oil finish was a very viscous  [like honey from the refrigerator] oil polished on 3 times over 3 days.  It has retained its sheen and protective qualities to this point.  It has lost the crisp appearance and detail of the wood which it had in the beginning.  This is sugar maple so it is harder than the maple used for violins.  The capillary action of the wood has drawn out the oil and muted the detail.

The other is a detail of the Balsam Ground at 20 years.

Each method we discuss will have its up and down sides.

on we go,

Joe

 

 

 

Worth 1000 words per photo - thanks, Joe!

[Oded Kishony]

Greetings:

recently saw a photo of the interior of the Messiah (Strad), it showed a thick, crustaceous, white residue, all around the F hole.

one has to believe it is original.

[JacksonMaberry]

2 minutes ago, Oded Kishony said:

Greetings:

recently saw a photo of the interior of the Messiah (Strad), it showed a thick, crustaceous, white residue, all around the F hole.

one has to believe it is original.

Does this mean the original mineral ground contained powdered crustaceans? 

Kidding, of course. Thanks for sharing the observation!

[Dave Slight]

Not quite crustaceans, but some historical documents mention powdered cuttlefish bone, to burnish the wood before varnishing.

[JacksonMaberry]

1 minute ago, Dave Slight said:

Not quite crustaceans, but some historical documents mention powdered cuttlefish bone, to burnish the wood before varnishing.

Cuttlebone is interesting. It can be surprisingly aggressive if you use a lot of elbow grease, but with a light touch it burnishes beautifully.

[David Beard]

47 minutes ago, JacksonMaberry said:

Cuttlebone is interesting. It can be surprisingly aggressive if you use a lot of elbow grease, but with a light touch it burnishes beautifully.

I think of it as a fine abrasive.  And use the word brunish to mean non-abrasive rubbing down.   ????

Bone, and hard agate are traditional burnishes.  

?? I'm curious. Is this common to describe a mild abrasive as a burnish?

 

[uncle duke]

1 hour ago, JacksonMaberry said:

Worth 1000 words per photo - thanks, Joe!

yes, but for a few dollars a furniture restore polish of sorts could be purchased and he'd be soon be back in business.

I like what Joe does too.

[JacksonMaberry]

2 minutes ago, David Beard said:

I think of it as a fine abrasive.  And use the word brunish to mean non-abrasive rubbing down.   ????

Bone, and hard agate are traditional burnishes.  

?? I'm curious. Is this common to describe a mild abrasive as a burnish?

 

I've referred to use of horsetail, another abrasive of sorts, as burnishing. But if I'm misusing language I'm happy to correct course.

[uncle duke]

8 minutes ago, David Beard said:

Is this common to describe a mild abrasive as a burnish?

I would think you could if a less than matte finish look could be achieved without much varnish removal.  Wet or dry process of getting there shouldn't matter.

[David Beard]

Well I'm not certain.  Words are slippery.  And they don't stay put. Their common usage tends migrate and change.  Since my reading materials tend to be more than a little out of date, you might be using a common meaning today?

From Merriam-Webster:

transitive verb

1a: to make shiny or lustrous especially by rubbing

//burnish leather

//burnishing his sword

b: POLISH sense 3

//attempting to burnish her image

2: to rub (a material) with a tool for compacting or smoothing or for turning an edge

//pottery with a smooth burnished surface.

 

 

I seem to be stuck in meaning 2.  Meaning 1 has lots of room for your usage.

[uncle duke]

Same here with #2. 

Can cuttlefish or similar provide a shiny surface?  Tripoli can but let's exclude tripli - what about crushed fish bones?  

[David Beard]

25 minutes ago, uncle duke said:

Same here with #2. 

Can cuttlefish or similar provide a shiny surface?  Tripoli can but let's exclude tripli - what about crushed fish bones?  

Cuttlebone, which you can get at pet stores as a supply for birds, is special.  It's like a foam.  

Both pumice and cuttle, in their solid rather than powdered forms, are special abrasives.   They are solid, but will erode and conform as you use them.   And they do this in away that depends on the direction of you motion.

This makes them ideal for perfecting a surface.   Because they are solid but erode while used, they behave differently than both files and sandpapers.  

[MikeC]

3 hours ago, Oded Kishony said:

Greetings:

recently saw a photo of the interior of the Messiah (Strad), it showed a thick, crustaceous, white residue, all around the F hole.

one has to believe it is original.

I saw that also.  I would think the Hills or  Vuillaume would have removed that when they had the instrument open if it were there at that time.  Yes or no?  So I am inclined to think it must have gotten deposited there sometime after the Hills had it open assuming they were the last ones to have it open.  How long ago would that have been?   I am curious as to what that substance is.   Since it seems to be mainly around the F holes I imagine it must have migrated there from the outside somehow through the holes.  

 

[uncle duke]

Couldn't it just be some kind of mold or fungus?

[David Burgess]

4 hours ago, MikeC said:

I saw that also.  I would think the Hills or  Vuillaume would have removed that when they had the instrument open if it were there at that time.  Yes or no? 

So I am inclined to think it must have gotten deposited there sometime after the Hills had it open assuming they were the last ones to have it open. .... 

...Since it seems to be mainly around the F holes I imagine it must have migrated there from the outside somehow through the holes. 

I suspect so too.

[Michael_Molnar]

11 hours ago, Oded Kishony said:

Greetings:

recently saw a photo of the interior of the Messiah (Strad), it showed a thick, crustaceous, white residue, all around the F hole.

one has to believe it is original.

That white residue appears on the lower bout rib, too. See Brandmair’s photos of that.

 

[David Beard]

11 minutes ago, Michael_Molnar said:

That white residue appears on the lower bout rib, too. See Brandmair’s photos of that.

 

Is it alum?  The messiah has a very bright undertone.  Alum has in many arts been used as a mordant to brighten the subsequent colors?

A saw a Banks cello opened up that looked like alum had been soaked all the way through maple.

[Advocatus Diaboli]

I vaguely remember David Ratray claiming it was Super Nikco a while back.  

[MikeC]

7 hours ago, Advocatus Diaboli said:

I vaguely remember David Ratray claiming it was Super Nikco a while back.  

Could be.    I wonder what it's ingredients are.  Googling hasn't turned up any info on that.