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Lab Techniques Project Slideshow

Avatar for Tj Haigler Tj Haigler
April 28, 2025
17

Lab Techniques Project Slideshow

Avatar for Tj Haigler

Tj Haigler

April 28, 2025

Transcript

  1. Screenwashing Project: NCSM Merry Oaks 19-713 Triassic North Carolina Results:

    Very little breakdown Routine: - Weighed out 600g masses of sediment and placed into five gallon and one gallon paint sieves - Placed bags submerged in water to soak for 48 hours - Came in to message bags at 24 hour mark - Removed bags from water and placed on drying rack - Reweighed bags and determined breakdown percent (100-((final/initial)x100)
  2. Molding Routine: - Mounted tooth upright with clay in the

    bottom of a small cup - Sprayed tooth with release spray - Measured and mixed equal parts Mold Max part A and B in separate cups - Poured a small stream of solution over the tip of the tooth - Waited for mold to solidify - Removed specimen Initial specimen used: Fossil Crocodile Tooth Late Cretaceous (70 Ma) South Carolina Peedee Formation
  3. Casting Routine: - Obtained rubber molds and sprayed the inside

    with release spray - Mixed equal parts Smooth Cast parts A and B - Quickly poured into multiple molds when mixture begins to feel hot to the touch - Waited for casts to harden and cool before removal Initial specimens casted: - Trilobite x2 - Coprolite - Hadrosaur Teeth - Gastropod x2 - Claw
  4. Preparing and Painting Casts Initial specimens painted: - Trilobite -

    Gastropod Preparation Routine: - Sanded down rough edges on the bottom of the casts - Washed casts briefly - Used primer to spray all sides of the casts and waited for the primer to dry Painting Routine: - Applied multiple coats of brown and orange acrylic paints - Antiqued the casts using black paint - Waited for casts to dry and sprayed a final clear coat over them
  5. Photography Routine: - Set up Neewer box with a ring

    light coming through the top of the box - Set all lights to be a bright white - Set up neutral colored background - Took pictures of specimen flesh with a scale bar - Made sure scale was accurate to how image was taken Initial specimen used: Fossil Crocodile Tooth Late Cretaceous (70 Ma) South Carolina Peedee Formation
  6. Keyence Routine: - Turned on Keyence monitor and TV screen

    - Centered fossil and placed parallel to the lined paper to help with scale - Set lower limit to when the green lines appeared clear - Set upper limit for when the top of the fossil appears blurry - Made sure to add a scale and move light source to the upper left corner
  7. 3D Printing Routine: - On the computer → find a

    3D model off of sketchfab and download and extract files - Open Creality Slicer and import downloaded file - Make model even with the bottom of the plate to aid the printing process - Click slice and download model onto flash drive - Set plate temperature to 60 degrees and nozzle temperature to 200 degrees - Insert flash drive into printer and select file - When done printing, remove from base with a spatula and gently remove supports
  8. SEM (Scanning Electron Microscope) Routine: - Placed 1mm specimen on

    stub - Loaded sample holder and slid holder into place lined up with the stage - Clicked the “observation” and “fast” buttons at top of monitor - Moved working distance to 15mm - Used joystick “Z/T” to move the stage to try to match to the working distance - Used focus, brightness, and contrast knobs on control panel - Pressed photo button and saved file to a USB drive Initial specimen used: Unknown Tooth Rebecca’s Hollow 1mm
  9. Consolidants and Adhesives Routine: - Weighed our empty bottle -

    initial mass of 62 grams - Our bottle was labelled 50:1 meaning one gram butvar to fifty grams acetone - We already had 10 grams of butvar that needed to be dissolved - Tried to get as close to 1:50 as possible but did not reach 500 grams of acetone - Only measured out 452 grams of acetone but since acetone evaporates rapidly our ratio was closer to 44:1 Some Notes: - Adhesion = taking parts and creating a whole - Consolidating = trying to keep things together - Acetone is reversible - Paleobond is nonreversible - Thin butvar - more acetone - Thick butvar (1 to 1) - Acetone kept in flammable cabinet
  10. Pin Vises, Air Scribes, Sectioning Routine: - Took oscillating tool

    and attached saw bit - Measured around perimeter of cast for class purposes - Carefully held tool against cast to let the tool do the most work and to not risk damaging bone - Cut a square of cast - Attached air scribe and turned on air flow, rotated air scribe to open up air flow - Air scribed away from my body and bone to remove small chunks of matrix - Kept matrix in a bag Some Notes: - Grind metal only, not casts - Air scribes require small amounts of oil to properly work - Make sure handle to air is perpendicular while plugging in (off)
  11. Plaster and Cradles Routine: - Made sure bone was glued,

    laid a small layer of thin paper towels over the bone, then laid ethafoam and formed to the bone, followed by a layer of thick paper towels that were formed to the bone - Cut burlap into sections with power tool and then into smaller strips - Added water into large bowl and then slowly added plaster powder in while mixing until the consistency is slightly thick and can stick to the burlap - Got burlap wet and then fed the burlap through the plaster and out to be laid onto paper towels - Continued to make strips until bone was covered - Waited until hardened, flipped, and cut off excess plaster jacket on sides of bone to produce a finished cradle
  12. Saws and Sectioning Routine: - Made sure water was flowing

    through saw and slowly guided the item forward and into the saw - If large rough spots or knobs were present, used grinder starting with coarse grained and moving to finer grained. Moved carefully back and forth on the grinder. - Polished the item using multiples of figure-8 motions on a rough surface that had water underneath to remove imperfections Some Notes: - Saws come in variety of forms including diamond plated (to cut mostly everything) - Used to see internal structures, calcification rates, mineralogy of fossiliferous materials, etc. - Important to not cross contaminate What I prepared: - Coprolite in epoxy - Iron formation chunk
  13. Final Projects Some Notes: - My two projects that I

    have chosen are mammoth versus mastodon dentition as well as demonstrating common symmetry types in invertebrates - 3D elements planned for each project: - Dentition: Mammoth molar and Mastodon molar - Symmetry: Trilobite (bilateral), Brachiopod (bilateral perpendicular to hinge), Bivalve (bilateral parallel to hinge), Ammonite (bilateral), and a regular Echinoid (radial/pentaradial)
  14. Final Projects Steps: - Created poster for symmetry using time

    scale elements for relation back to Evolution of the Earth lab in which symmetry was a component of - Created short write ups about differences in mammoth and mastodon molars as well as created simplified skull tracings for each - Found lateral view photos of mammoth and mastodon skulls and a simple cladogram - Began 3D prints for all projects - Primed and painted 3D prints for all projects - ABH assisted in printing 11x17 for my symmetry “poster” - Printed, laminated and cut out all other write ups, labels etc. - Hot glued all components onto a foam board for final projects and cut to size