Elasmosaurus Tooth Repair

[jdiaz55]

I received an awesome set of Moroccan matrices from @caldigger (thanks again!) that included a cracked elasmosaurus tooth. I didn't consolidate the tooth before prepping, as the matrix surrounding the tooth was far harder than the rest of the block, leading me to believe it had been sufficiently consolidated. It split at the crack whole handling it before prep work even begun, so I continued with the rest of the tooth and got the rest out pretty cleanly. The fossil isn't valuable, so I'm not too worried about perfection! Its all part of the learning experience for me.

 

My question is about the correct order to go about repairing this tooth. When you line up the pieces, there is still a small hole from a missing section, and I suppose filling it with the matrix and then adding a layer of Paraloid dilute would be the best way to go?

 

So here is my (tentative) plan of repair:

 

Consolidate the pieces in the dilute

Super glue the bits back together as cleanly as possible

Fill in the cracks with wet matrix (?)

Let it dry, then gently coat again with the dilute solution

 

Would exposing it to the dilute twice be overkill? And I know acetone tends to dissolve super glue, but I assume the glue would hold if it's inside the tooth and the second coat of Paraloid goes on just the outer layer after it has all dried? 

 

Hopefully I explained my intentions well, and I'm looking for ideas as to what would be the best order to attempt these steps in or otherwise a preferable method (if there is one) of repair! 

[jpc]

The first thing that an acetone-based consolidant will do if you put it on something that already has some acetone-based consolidant is the acetone in Dose Two will dissolve the set up consolidant from Dose One and it will fall apart.  Acetone will dissolve superglue but it takes many minutes.  It dissolves vinac/paraloid/butvar in a matter of seconds.  I see no reson to soak this in dilute anything.  If you have good fits with no gaps, glue them in place with either Paraloid or cyanoacrylate (superglue).  Then keep going.   

[jdiaz55]

40 minutes ago, jpc said:

The first thing that an acetone-based consolidant will do if you put it on something that already has some acetone-based consolidant is the acetone in Dose Two will dissolve the set up consolidant from Dose One and it will fall apart.  Acetone will dissolve superglue but it takes many minutes.  It dissolves vinac/paraloid/butvar in a matter of seconds.  I see no reson to soak this in dilute anything.  If you have good fits with no gaps, glue them in place with either Paraloid or cyanoacrylate (superglue).  Then keep going.   

That makes sense! Part of the problem is that there is a small gap when the pieces are put together that was once filled with matrix that crumbled when I began preparation, so I'm partially wondering how to properly re-fill that gap with matrix.

 

How would one use Paraloid as a glue without acetone?

[Harry Pristis]

30 minutes ago, jdiaz55 said:

That makes sense! Part of the problem is that there is a small gap when the pieces are put together that was once filled with matrix that crumbled when I began preparation, so I'm partially wondering how to properly re-fill that gap with matrix.

 

How would one use Paraloid as a glue without acetone?

 

Why would you want to restore the damage (the matrix-filled gap)?  My recommendation is that you entirely remove gap matrix, then fill the gap with epoxy putty, which you can purchase in brown and can sculpt to a nicety.

[Ptychodus04]

44 minutes ago, jdiaz55 said:

That makes sense! Part of the problem is that there is a small gap when the pieces are put together that was once filled with matrix that crumbled when I began preparation, so I'm partially wondering how to properly re-fill that gap with matrix.

 

How would one use Paraloid as a glue without acetone?

I agree with @jpc and @Harry Pristis. Superglue the pieces together. Fill the crack with brown putty (I like Apoxie Sculpt). Then brush on some dilute Paraloid to stabilize if needed. Keep in mind that enamel does not readily absorb consolidation solutions so you're basically putting it on the surface only.

[jpc]

1 minute ago, Ptychodus04 said:

I agree with @jpc and @Harry Pristis. Superglue the pieces together. Fill the crack with brown putty (I like Apoxie Sculpt). Then brush on some dilute Paraloid to stabilize if needed. Keep in mind that enamel does not readily absorb consolidation solutions so you're basically putting it on the surface only.

... and that might make it artificially shiny if the consolidant is too thick.