Gap filler question

[Browning]

Hello, trying to reconstruct this horn. I would like to practice filling the gap with something removable before I do anything more permanent. Any suggestions? Most things I find are for small gaps, not large. Can paranoid b72 be used for large gaps? How removable is it? Is there a removable wax I can try? 

[Pagurus]

45 minutes ago, Browning said:

Can paranoid b72 be used for large gaps?

 

I'd be afraid to. (Sorry, I couldn't resist.)

[Fin Lover]

From the picture, that looks like more than just a gap to me. 

[jpc]

you can certainly doit with Paranoid Paraloid B-72.  The Gray Fossil site in Tennessee has been doing a lot of this by making large paraloid joints.  If you use a thick mix of it, the stuff stretches, like taffy and you can build bridges with it.  Put your two fossil pieces on sandbags or something where you won't have to move them as you build.  I don't know if they have any videos online but it might be worth looking into it.

 

Additionally, Carbowax is a water soluble wax that can be used for exactly this.  It is sold to regular folks in the US as Miralax.  Melt it under low heat then you can paint it into place to make your joint.  Build up layers and it might actually work.  And it comes off in warm water.  

 

Additionally, yeah that seems like more than just a gap.   : )

 

 

 

Edited February 25 by jpc

[rocket]

we sometimes use akepox clay or skulpt to fill gaps like these or for modelling.

Easy to handle, you can color it and - if you have a little experience with modelling - it works fantastic

I do not know where to buy in the US, found some websites having it like Akemi AKEPOX 5010 | Direct Stone Tool Supply, Inc or AKEPOX® 5010 Knife Grade - The Compleat Sculptor

(looks very expensive, we have some suppliers in Germany the offer it really cheaper e.g. HAUFWERK.COM: Geologie & Paläontologie – Apoxie Sculpt, Braun – verschiedene Größen, so I would assume there are many dealers in the US offering akepox at a lower price)

Edited February 25 by rocket

[hadrosauridae]

use modeling clay such as plastilina, that doesnt dry out.  The section you trying to replace is much too large most options. Clay also lets you play with texturing methods before you  move to remaking it in a permanent way.  For a permanent solution, you can do the same with a 2-part epoxy such as paleo-sculpt.  

Edited February 25 by hadrosauridae

[jpc]

the OP asked about things that can be removed.  While epoxies will do the job very well, they are a pain in the patootie to remove.  I would avoid any oily clays, which are the ones that don't dry out.  The oil will seep into your fossil and never come out.  

[Browning]

Thank you for the replies. I will look into each. And yes I am looking to avoid any oil residue as jpc mentioned. 

 

Those of you who think my "gap" term is incorrect, what would you call it? Just curious.

[Fin Lover]

To me, a gap would be if the two pieces fit flush together but there's just a little shard missing.  These don't look like they went together flush...there is quite a bit missing, from what I can tell in the picture.  

[Jaybot]

I'd highly recommend a thick mix of paraloid B-72.  Please note that it might take a few minutes to dry mostly, so have some support ready to hold the piece in place.  Once dry, paraloid is pretty strong, and will definitely hold everything together.  I pretty much only use paraloid now, since I like the ability to reverse my mistakes

[Ptychodus04]

On 2/25/2024 at 3:37 PM, jpc said:

The Gray Fossil site in Tennessee has been doing a lot of this by making large paraloid joints.

 

I recently heard about this process. It's an amazing idea for reducing added weight to repaired specimens!

 

On 2/25/2024 at 8:41 PM, Jaybot said:

Please note that it might take a few minutes to dry mostly

Very thick solutions can take several days to fully set. The lower the ratio of acetone to Paraloid in the solution, the longer it takes for the acetone to evaporate completely.