Butvar or Paraloid for White River Verts?

[Minnesota Nice]

I am looking specifically for a preference in use as a  consolidant for Verts in Whiteriver formation matrix. 

[FossilDudeCO]

I prefer paraloid as a consolidant

My experiences are with Merycididon and leptauchenia

[Ptychodus04]

Paraloid, Butvar, or PVA. Whichever you can get the easiest and cheapest. All 3 are well used in conservation arenas.

 

I prefer PVA.

[Minnesota Nice]

37 minutes ago, FossilDudeCO said:

I prefer paraloid as a consolidant

My experiences are with Merycididon and leptauchenia

Can you give me an idea as to ratios? Brushed on vs submerged? I have seen reference to slowing the drying process by creating an air restricted environment. Thoughts? Again this would be for material found in the white water formation. 

[Minnesota Nice]

36 minutes ago, Ptychodus04 said:

 

 

I prefer PVA.

Thanks , can you elaborate on pva

[Ptychodus04]

PVA is an acronym for the polymer polyvinyl acetate. It is a stable consolidant and adhesive soluble in acetone and denatured alcohol. 

 

It it was once sold under the trade name Vinac. 

 

It it is applied in the same manor as Butvar either by complete submersion of the specimen or local application by drop or brush.

 

Are you looking for any specific information?

[TqB]

Whilst widely used, PVA is effectively irreversible once dry.

Butvar (I think) and Paraloid remain easily soluble with acetone or alcohol.

[Opisthotriton]

With all of these products, you have to be specific with the names due to the wide variety of chemical formulas used. PVA (polyvinyl acetate) encompasses a large group of materials. Vinac (old name, now sold as McGean B-15) is a PVA, and is easily reversible/soluble with acetone and/or alcohol, same as butvar/paraloid/acryloid. You might be thinking of a PVA emulsion like Elmer's white glue, which is water-soluble when wet, and effectively irreversible once dry.

[Minnesota Nice]

FYI,

Bought 1# Paraloid B72 from these folks $15.00 plus $8.00 shipping. Quick, easy and great customer service.

 

Conservation Resources International, LLC

http://www.conservationresources.com/Main/section_40/section40_04.htm

Phone: (800) 634-6932   Fax: (703) 321-0629

E-mail: sales@conservationresources.com

[jpc]

Are you looking for a field consolidant or something to use at home after you get the things cleaned?  I use McGean PVA-15 ('vinac') in the field but rarely ever put anything on them when preparing them.  If they are falling apart I glue them together with PaleoBond.  White River bones tend to be pretty solid.  

[Minnesota Nice]

23 minutes ago, jpc said:

 White River bones tend to be pretty solid.  

 Sorry I wasn't more clear. Yes this is for prep at home and you're right most of the material is pretty stable I do have a scull, partial sculls and jaw bones that are fragile. This will be my first experience with prepping!

[Minnesota Nice]

What are your thoughts of using paraloid at a 50-50 ratio for gluing pieces together. I like the idea that it's reversible with acetone.

[jpc]

50-50 is probably way too thick, but then I am a vinac guy.  PS... vinac (McGean B-15) is easily reversible with a small dose of acetone.  But yes, a thick solution of paraloid should be a good glue.  I am just not sure the ratio.  Did you get any instructions with your paraloid purchase?  If it says 50-50, go for it.  

[Minnesota Nice]

50/50 was information from the technical paper referenced often here for adhesive.  I have a pound on the way and I will post a picture of the consistency later.  

[Minnesota Nice]

My very first prep will be this jaw section. It is in two pieces and need cleaning and consolidating. I plan on posting a step by step for critique 

[Ptychodus04]

50/50 is a good solution for a VERY thick glue. I would suggest pouring 50:1 (very thin) onto both bonding surfaces several times prior to applying the glue. This will help to give you a stronger bond. For this piece, I would get everything positioned right and wrap it in about 75 rubber bands. Come back in a few days and you should have a very strong yet reversible bond. Excess glue can be cut away with a scalpel and dissolved with local application of acetone.

[jpc]

what sorts of tools do you plan to use on this project?  By the way, nice chunk of rhino jaw.  

[Minnesota Nice]

4 hours ago, Ptychodus04 said:

50/50 is a good solution for a VERY thick glue. I would suggest pouring 50:1 (very thin) onto both bonding surfaces several times prior to applying the glue. This will help to give you a stronger bond. For this piece, I would get everything positioned right and wrap it in about 75 rubber bands. Come back in a few days and you should have a very strong yet reversible bond. Excess glue can be cut away with a scalpel and dissolved with local application of acetone.

Hey Kris,

Thanks for the pointers. My thought is to submerge in 50:1 then bond together,THEN do some final cleaning and prep. I am concerned that the piece will crumble if I don't consolidate 1st. 

[Minnesota Nice]

Just now, jpc said:

what sorts of tools do you plan to use on this project?  By the way, nice chunk of rhino jaw.  

Jpc,

I am open to suggestion as this is my very first vert prep. See my comment above. I have a selection of dental instruments that I plan on using to remove the traces of matrix that remain. I also like the idea of filling the joint where the repair is made with Apoxie Sculpt tinted close (but not to close) to the surrounding material. Again, I want to stress that I am looking for guidance and opinions. 

[Ptychodus04]

Don't fully consolidate (immersion) prior to preparation if you are using hand tools. This will remove the separation between matrix and fossil making the preparation almost impossible to do by hand. 

 

If if it is so fragile that it will crumble without consolidating, you may not have a choice. I try to avoid this scenario when possible. If this is the case, repair with cyanoacrylate rather than the Paraloid and then consolidate by the brush method.