PVA Glue has a place in violin making/restoration. Any thoughts?

[Nikos Matsablokos]

I've been following Maestro Kimon's YT channel for a while. As much as I appreciate the content he uploads, I always couldn't get over that he uses pva glue both for the center Joints and for repairs. Everyone knows that unlike hide glue when something is glued with PVA and most other glues and for some reason fails, then the glue has to be removed either by sanding scraping or planing because new glue won't adhere to the old one. 

And this brings me to his latest video. It has to do with supporting the use of PVA glue in violin making. Supporting the fact that he doesn't plan to open the center joint any time soon and even if it gets open he can put some more pva glue in the crack/gap to fill it. I doubt such a repair will last too long and I fail to believe that the use of hide glue is just an homage to the past, since there are infinite more reasons why you'd want to use hide glue instead of pva glue, the main one being that it adheres to previous layers.

But these are my thoughts... Anyone interested can watch his video and give his/her thoughts on this matter. As far I am concerned I respectfully disagree with his statements.

https://www.youtube.com/watch?v=jRQ-nHfHZTo

 

Edited December 26, 2021 by Nikos Matsablokos

[Wood Butcher]

It’s worth remembering that anyone can post videos on YouTube, and spout out anything they like, with reasons to support their nonsense. It doesn’t mean it’s the accepted way, or would be used by anyone with proper training.

Even referring to oneself as maestro seems pretentious. A bit like how there are so many “master” violin makers in America, even though there is no actual qualification one can obtain there, to bestow such a title.

[Jeffrey Holmes]

1 hour ago, Wood Butcher said:

Even referring to oneself as maestro seems pretentious. A bit like how there are so many “master” violin makers in America, even though there is no actual qualification one can obtain there, to bestow such a title.

I believe the Federation offered a Master designation (test, etc) in the US at some point, but I don't know if that's still the case... but yes.  The "Master" term is kind of thrown around on this continent. We don't have a guild, or a government regulated entity for violin making here. There are a number of luthiers who have that designation who relocated here from Europe, and a number of Americans who went to Europe to obtain their "Master" status, however. Trying to sort out who is who (self acclaimed, earned) is pretty difficult for those not in the know.

Nikos; I have PVA in the shop... I use it for gluing on parchment and building jigs, but not much else.

[Thomas Coleman]

2 hours ago, Nikos Matsablokos said:

he doesn't plan to open the center joint any time soon and even if it gets open he can put some more pva glue in the crack/gap to fill it

The first shouldn't be an issue...It'll open by itself.  It's called "creep" and is well documented with joints under stress that were glued with PVA.  The second...good luck.

I don't mean to be flippant and by all means, if you doubt me, please confirm (or not) these things for yourself.

[FiddleDoug]

I’ve used it for gluing parchment patches on bridges, gluing linen onto ribs, gluing on some cleats, and a couple of tiny drops to hold nuts in place, I wouldn’t use it for any structural joints, or crack repair.

The glue that I use is Lineco pH neutral, archival glue. It’s used for book restorations.

[Nikos Matsablokos]

I have pva glue as well and I have used it for years, for general woodworking tasks, because its very convenient. You squeeze the bottle you put some glue that is it you are done. 

But I wouldn't want it anywhere near my instruments. Trust me, if I thought it would be as good as hide glue I would switch in an instant. Mainly because it would save me from the infinite amount of times that I've forgotten to turn off the glue pot (baby milk warmer...whatever works right?) which would create a very, lets just say unpleasant, smell in the workshop the next day I go there .

However in my mind hide glue will always be the superior glue for our line of work because pva will cause many more problems in the long term, than the temporary convenience it might provide.

[Pate Bliss]

4 hours ago, Wood Butcher said:

referring to oneself as maestro seems pretentious. 

It's nutty, to be honest.  Would expect to see nutty methods and materials too

[Wood Butcher]

There are cases, when the titles are bestowed by one’s peers out of respect for their abilities. This, for me, is the only real way to be a maestro.

[Davide Sora]

9 minutes ago, Wood Butcher said:

There are cases, when the titles are bestowed by one’s peers out of respect for their abilities. This, for me, is the only real way to be a maestro.

I agree. Unfortunately, some people attribute these titles to themselves only for marketing. Personally it has the opposite effect on me, that is negative marketing (I would keep well away from those who do it).

Not even the Cremona violin making school assigns the title of "Master violin maker", on the final diploma it is simply written "Diploma di qualifica di liutaio" (Diploma of qualification of violin maker).

[Andreas Preuss]

I think that ‘masters’ who use PVA glue on other peoples work for ‘restoration’ should be broken on the wheel and quartered in public.

[Mr. Bean]

Glueing with hide glue is one of the easier skills to achieve in violin making i.m.h.o, so why grabbing PVA?

[uncle duke]

If I'm not mistaken my center seams turned out better this time around using Titebond ll as compared to using Titebond original all other times - I know my joining/planing skills haven't changed much and the word "better" as used by myself here means simply a tighter closed, less visual seam.

I'm just a hobbiest with some wood laying around, for those not in the know.

[Brad Dorsey]

Since it is almost universally accepted that hide glue is the only proper adhesive for violin repair, almost all high-quality repairs have been done with hide glue.  Therefore, the repairs we see that were done with yellow or white glue were almost always done by incompetent hacks.  Repairs done by incompetent hacks generally have other problems independent of the type of glue used:  Cracks are glued out of register, excess glue is not cleaned up, woodwork is crudely done, parts are poorly fit, varnish retouching is abysmal or non-existent, etc.  The work is generally a mess.  Hacks give white/yellow glues a bad reputation.  But is this reputation due to the glue itself, or is it due to the sloppy work done by most of the people who use it?  Is there ever a place for white/yellow glue in high-quality repair work?  I believe that there could be in some situations.

My teacher, Hans Nebel, glues crack reinforcement cleats with white (Elmer's) glue, explaining that the slight flexibility of the dry glue will accommodate cross-grain wood movement, reducing the possibility that the cleats will become loose and cause buzzes.  He uses yellow glue (Titebond II) for rib doublings in areas subject to perspiration (violin and viola upper treble and lower bass ribs), saying that it is more resistant to heat and moisture than hide glue.  He glues nuts with Elmer's if his glue pot is not hot.  He uses it to glue linen reinforcements on ribs and blocks.  He suggests using Titebond to secure rib corners as an alternative to fitting corner blocks in cheap violins made without them.

Hans tells the story of how he reset the neck of what some consider to be the only known Del Gesu cello under Sacconi's supervision at the Wurlitzer shop in the 1950s.  The neck required lengthening by gluing, end-grain to end-grain, additional wood to the foot.  They decided to use Elmer's.  When the cello later came back with the neck broken out, they found that the Elmer's joint had held.

I am not advocating for widespread use of white/yellow glue in violin repair or making.  I think it is always a bad choice for joining plates, gluing cracks, gluing plates to ribs, and gluing ribs, necks, fingerboards, patches and purfling.  I have never made a violin; if I did, the nut is the only thing I might glue with something other than hide glue.  But I think that there are a few places where white/yellow glue could be appropriate in repair.  In general, these are places subject to heat and perspiration, places where getting a well-fitting joint is impossible, or places where a little flexibility in the bond might be an advantage.  The use of white/yellow glue should never be used as a substitute for poor-fitting joints or other sloppy work.

[ctanzio]

Just to interject a little material science into this thread...

Common white and carpenter glues are Poly Vinyl ACetate emulsions and more properly abbreviated as PVAC.

PVA is typically used to refer to Poly Vinyl Alcohol. It is used as a primer or filler in paints, or as a protective cover for foods. PVA is derived from PVAC and both can occur together in some emulsions by design.

PVAC has very low toxicity, safe to handle without special precautions, and dries by evaporation of its water-based solvent. It is easily cleaned up with water before it dries.

Common PVAC glues have tensile and shear strengths comparable with woods used in violin, furniture and cabinet making. There is no worry about the strength of the bond.

It is also resistant to water and to solvents that occur in varnishes, more so than hide glue. So that is an advantage.

It has more resistance to fracture than hide glue. That is a good thing unless you want to reverse the joint. Then that is a bad thing. The tendency of hide glue to fracture under tension and shear loads is what makes it easy to open a joint for repairs.

Sadly, common PVAC glues has poor creep resistance, especially in humid conditions. Compression loads are fine for most furniture and cabinet joints. Pins and screws can be inserted at unseen locations to protect against tension and shear creep.

But for violins, bending and shear loads along the seams of the belly and back, and between the fingerboard and neck, may cause the joint to slowly open or slide. 

There are many ways to prepare PVAC to dramatically increase its resistance to creep. Wood glues sold for exterior use generally fall into this category. The Maestro might want to upgrade to one of the Titebond exterior glues.

[CaseyLouque]

Wouldn't Fish Glue be a good alternative to PVA?
I read that it dosn't suffer from the creep issues of PVA can be reworked with moisture.

Its ready to use in a bottle no heating or wetting required. Similar curing time.

 

I am not advocating it use over hide glue. I believe hide glue should be used.

But if I had to choose to do a repair on an instrument previously fixed with PVA or fish glue I would rather work with the fish glue.

 

[Marty Kasprzyk]

I use Gorilla glue for my plate center joints but use hide glue for everything else.

[Bill Yacey]

2 hours ago, Brad Dorsey said:

Since it is almost universally accepted that hide glue is the only proper adhesive for violin repair, almost all high-quality repairs have been done with hide glue.  Therefore, the repairs we see that were done with yellow or white glue were almost always done by incompetent hacks.  Repairs done by incompetent hacks generally have other problems independent of the type of glue used:  Cracks are glued out of register, excess glue is not cleaned up, woodwork is crudely done, parts are poorly fit, varnish retouching is abysmal or non-existent, etc.  The work is generally a mess.  Hacks give white/yellow glues a bad reputation.  But is this reputation due to the glue itself, or is it due to the sloppy work done by most of the people who use it?  Is there ever a place for white/yellow glue in high-quality repair work?  I believe that there could be in some situations.

My teacher, Hans Nebel, glues crack reinforcement cleats with white (Elmer's) glue, explaining that the slight flexibility of the dry glue will accommodate cross-grain wood movement, reducing the possibility that the cleats will become loose and cause buzzes.  He uses yellow glue (Titebond II) for rib doublings in areas subject to perspiration (violin and viola upper treble and lower bass ribs), saying that it is more resistant to heat and moisture than hide glue.  He glues nuts with Elmer's if his glue pot is not hot.  He uses it to glue linen reinforcements on ribs and blocks.  He suggests using Titebond to secure rib corners as an alternative to fitting corner blocks in cheap violins made without them.

Hans tells the story of how he reset the neck of what some consider to be the only known Del Gesu cello under Sacconi's supervision at the Wurlitzer shop in the 1950s.  The neck required lengthening by gluing, end-grain to end-grain, additional wood to the foot.  They decided to use Elmer's.  When the cello later came back with the neck broken out, they found that the Elmer's joint had held.

I am not advocating for widespread use of white/yellow glue in violin repair or making.  I think it is always a bad choice for joining plates, gluing cracks, gluing plates to ribs, and gluing ribs, necks, fingerboards, patches and purfling.  I have never made a violin; if I did, the nut is the only thing I might glue with something other than hide glue.  But I think that there are a few places where white/yellow glue could be appropriate in repair.  In general, these are places subject to heat and perspiration, places where getting a well-fitting joint is impossible, or places where a little flexibility in the bond might be an advantage.  The use of white/yellow glue should never be used as a substitute for poor-fitting joints or other sloppy work.

Hide glue can be removed with some warm water and a rag, if necessary. PVA? you pretty much need to remove some wood to get back to a virgin wood gluing surface; not exactly a positive attribute for conserving valuable instruments.

[Nikos Matsablokos]

10 hours ago, Davide Sora said:

I agree. Unfortunately, some people attribute these titles to themselves only for marketing. Personally it has the opposite effect on me, that is negative marketing (I would keep well away from those who do it).

Not even the Cremona violin making school assigns the title of "Master violin maker", on the final diploma it is simply written "Diploma di qualifica di liutaio" (Diploma of qualification of violin maker).

We are on the same page, I've seen a lot of this self given titles being tossed around on the internet. Terms like maestro, distinguished etc. being tossed around. These titles should not be given to ones self, otherwise they lose their meaning. The reasons why someone thinks they can give titles like  master or distinguished to themselves completely escapes me.

I doubt that even Stradivari would have the ego to call himself  a master, even though he was. This title was given to him by the experts who studied the magnificent instruments that he made, during his time as @Wood Butcher rightfully pointed out. 

Such titles should be given and not proclaimed. Let alone to someone who has the audacity to not only use pva glue on his clients, but to also encourage the use of it.

[Nikos Matsablokos]

2 hours ago, Bill Yacey said:

Hide glue can be removed with some warm water and a rag, if necessary. PVA? you pretty much need to remove some wood to get back to a virgin wood gluing surface; not exactly a positive attribute for conserving valuable instruments.

Exactly and in his video he supports that, " if a joint that I previously glues with white glued opens up I can put some more in there to fix the gap, unlike hide glue which would melt previous layers and further expand the crack/gap". Never mentions, probably because he doesn't know it (hence I find what he says dangerous) that pva glue doesn't adhere to previous layers of pva, like you said the wood has to be removed. 

And to counteract his argument that hide glue will further open up the joint, even if this happens, the melted layers of the previous glue will melt and after a bit they  will dry again, because that is what hide glue does. He used an argument against hide glue, that is part of the reason why we choose to use it in the first place...

[HoGo]

4 hours ago, Bill Yacey said:

Hide glue can be removed with some warm water and a rag, if necessary. PVA? you pretty much need to remove some wood to get back to a virgin wood gluing surface; not exactly a positive attribute for conserving valuable instruments.

I've read this so many times but never seen any real DATA. I don't want to advocate use of these glues in inappropriate places but some of these ideas are at least partly hearsay.

You can clean standard PVAC (not waterproof) with vinegar solution and don't need to remove wood. Of course using clean water is easier. I've read many times that white glue will not stick to surfaces previously glued with PVA but never seen any tests. Guitar folks mostly reglue guitar bridges with Titebond as was used in factory and they hold just as well as original and noone really cleans the surface of spruce top too aggressively to put a hole through the top - most failures are caused by overheating the instrument and release quite cleanly.

[Don Noon]

I have all kinds of glues in my shop, and they have different uses.  For structural instrument glue, hide is the only thing I'd ever use.  For some non-structural things I might use PV or fish glue, primarily to avoid firing up the glue pot.  Urethane glues and epoxy are good for fixtures, where the water in the other glues might cause warpage.

Not that I would ever recommend such a thing, but I can see how PV glue might survive on the top center joint of a violin, as the bridge pressure and arching would tend to put the joint in compression (mostly).  

[donbarzino]

Original titebond is an aliphatic resin, titebond II is a polyvinyl alcohol  and titebond ultimate is based on a

proprietary polymer. Besides the differences in water resistance I wonder if there are notable differences

in creep resistance.

[Jeffrey Holmes]

Just to shake things up a bit, I believe some classical makers used casein glue for center joints and other joints.  If I recall, Roger Hargrave also mentioned this in a previous discussion on MN and wrote an article, originally for The Strad I think, on the subject.

[CaseyLouque]

@Jeffrey Holmes

Are you talking about this article?

The case for casein
Roger Hargrave proposes a casein link with Stradivari.

[Jeffrey Holmes]

1 hour ago, CaseyLouque said:

@Jeffrey Holmes

Are you talking about this article?

The case for casein
Roger Hargrave proposes a casein link with Stradivari.

Yup. Here's a link if anyone would like to read it: Hargrave article