From Crab to keichousaurus fossil

[DLB]

new round of pics 

[DLB]

[DLB]

[DLB]

this one is almost done

[DLB]

[DLB]

[DLB]

its a slow process but i love seeing them emerge from there rock tomb.

[Ptychodus04]

Purty.

[DLB]

11 minutes ago, Ptychodus04 said:

Purty.

thanks im trying glade nature did most of the work

[RJB]

Good goin Dusten.   Gunna be interesting to see the final results.

 

RB

[DLB]

1 hour ago, RJB said:

Good goin Dusten.   Gunna be interesting to see the final results.

 

RB

Thanks Ron 

[Ptychodus04]

@DLB, I finally remembered to check the buffer amount for the acid solution.

 

According to Rutzky et al (chapter 7 of Leiggi and May 1994), use 1 teaspoon of calcium phosphate for each liter of solution as a buffer. This is based on a 5% formic acid solution. For your 80% solution you would need 16 tablespoons per liter of solution but soaking at this strength would be very detrimental to the specimen due to the violence of the reaction.

 

Also, if you use a hardener between acid baths as discussed, make sure you use Paraloid B72 or Vinac B15. Don’t use Butvar as it is soluble in formic acid.

[RJB]

On 12/8/2018 at 8:26 PM, Ptychodus04 said:

According to Rutzky et al (chapter 7 of Leiggi and May 1994), use 1 teaspoon of calcium phosphate for each liter of solution as a buffer. This is based on a 5% formic acid solution. For your 80% solution you would need 16 tablespoons per liter of solution but soaking at this strength would be very detrimental to the specimen due to the violence of the reaction.

   Its almost like you know what your talking about Kris. 

  And also @DLB where in tarnation is the finished results for all these lizards?

 

RB

[steelhead9]

On 10/11/2018 at 8:00 AM, DLB said:

The brown one seems to be a heck of alot softer way easyer to work with.

They always are!

[steelhead9]

On 10/15/2018 at 8:20 PM, DLB said:

well from what limited experience i have . when i tryed to just sand blast it was vary hard even useing 120grit aluminum oxide  didnt even make a dent.so the use of acid softens a thin  layer making it easyer to prep that layer. the softer one might have been ok to sand blast only but it even had hard spots.

 

50 micron dolomite at low pressure (around 40psi) works well on most specimens, but it’s slow going. Aluminum oxide in my experience takes the bones right off with the matrix. I’ve never had luck with strong acid as I always end up with degraded bones. Just a quick wash after blasting with 5% hydrochloride solution to clean things after applying paraloid to the bones. Keichousaurs are some of the hardest fossils to prep well. What you can get for them if you sell them is not worth the effort. By the way, yours look great!

[Ptychodus04]

1 hour ago, RJB said:

   Its almost like you know what your talking about Kris. 

  And also @DLB where in tarnation is the finished results for all these lizards?

 

RB

Ha! Just good reference material sir.

[DLB]

8 hours ago, steelhead9 said:

They always are!

lol

 

8 hours ago, RJB said:

   Its almost like you know what your talking about Kris. 

  And also @DLB where in tarnation is the finished results for all these lizards?

 

RB

well one is almost done i had to stop prep  because of cold weather i only use the acid out doors to limite my exposure.

[DLB]

I will try and  get  pics up soon of the mostly complete  one.

[DLB]

tell you all what tho i really learned some stuff from this one 

[Bobby Rico]

1 minute ago, DLB said:

I will try and  get  pics up soon of the mostly complete  one.

I have been thinking about this thread and would really like to see it’s progress when ever you can. Very interesting thread. Cheers Bobby 

[DLB]

ok fellas here is the one im calling it about as good as i can get it. It has its problems like most fossils but it is my first time preping these buggers so dont judge me to harshly. Ive learned a few things from this experience and since ive neved used acids to prep i feel i did alright. It reminds me of my first crab prep lol.

[Ptychodus04]

@DLB, no judgment here you did a good job. The first is always the hardest because that’s where you make all your mistakes.  Well done.

[RJB]

  Hard to tell in the picture, are there any fingers on the upper arms?    but after seeing this, im wondering if there is anything you can do to the rock to make it more uniform?  All in all id say you did purty good. 

 

RB

[Tidgy's Dad]

Good work! 

[DLB]

4 hours ago, RJB said:

  Hard to tell in the picture, are there any fingers on the upper arms?    but after seeing this, im wondering if there is anything you can do to the rock to make it more uniform?  All in all id say you did purty good. 

 

RB

so the hands were closed not a vary displaying the hand i was thinking of trying to make it more uniformed but wasnt quite sure on if i was to do this with a sand blaster or a buffing wheel?