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ilan
04-03-2006, 18:07
hi I would like to get some plaster casts of some of the local wild lifes foot prints , I know ray used a sand trap to get some prints . Has anyone tried it. can you get plaster casts from the sand or is there a better method ie sieved earth or can you suggest a better media . (In case you are wondering its to show the local cub scouts ) thanks ian

Toddy
04-03-2006, 18:30
I can only tell you what I did. I bought Fastset plaster which is intended for interior fine details. Cost about 5 for 2kilos (while ago, maybe 5 years). I just made up a small bowlful and covered it with clingfilm. Went walkabout, found tracks I recognised...cat, squirrel, blackie, etc., and spooned the stuff into and over the track. Ten minutes later I lifted it out and while it wasn't dry, it was firm enough to carry away. I left it to dry out properly on top of the radiator before I brushed off the excess earth and stuff. It worked fine.
I'm told that if time's no object then a mixture of sand and cement can be poured dry into the track and it will absorb enough moisture from the ground to set itself overnight.
There have to be other ways though. Man made resin maybe?

Cheers,
Toddy

pierre girard
04-03-2006, 20:06
You can get the very best casts using sulfer in snow. Very fine detail. We often use this in criminal cases.

PG

jason01
04-03-2006, 20:37
I have done some lifecasting using dental alginate, good for very fine detail but not ideal for tracks I think, and its quite pricey. To make a positive of the alginate cast I use plaster of paris or stonecast which is similar to plaster of paris but stronger nd capable of holding finer detail, I think that might be good for casting tracks, should be available at model shops fairly cheaply.

Adi
04-03-2006, 20:41
The best way to get casts is with dental stone, it holds a better definition of the print. You can use it on snow as well by firstly spraying paint onto dry cold snow or snow print wax on wet or melting snow.

This is just some of the ways crime scene investigators collect spoors for evidence purposes.

Ogri the trog
04-03-2006, 20:44
You can get the very best casts using sulfer in snow. Very fine detail. We often use this in criminal cases.

PG

Any chance you could expand on this Pierre?
Today I saw some pheasant tracks in the snow that held the most intricate detail I've ever seen in an animal track - not only the individual pads on the sole of the foot/claw but the folds of skin as well, it would be great to know how to lift this type of cast.

ATB

Ogri the trog

Adi
04-03-2006, 21:02
Any chance you could expand on this Pierre?
Today I saw some pheasant tracks in the snow that held the most intricate detail I've ever seen in an animal track - not only the individual pads on the sole of the foot/claw but the folds of skin as well, it would be great to know how to lift this type of cast.

ATB

Ogri the trog

To use sulfur to take casts you need sulfur pellets.

You melt the sulfur but being very careful not to let in ignite and don't breath in fumes. Then let it cool to just above freezing point then carefully poor into print making sure you cover all parts. the sulfur will set as soon as it makes contact with the snow. Keep pouring until the cast is about 2 cm thick. Leave to fully set.

Adi
04-03-2006, 21:11
I forgot to say before you prepare the sulfur or plaster spray the spore with primer paint or snow print wax if you can get it, to help fix the surface of the snow in and around the spoor. If you are taking photos of spoors in the snow it is often the best time to take a photo after you have sprayed the paint as all of the detail in the spoor can be seen.

ilan
04-03-2006, 23:04
hi unfortunatly we have not got any snow i was thinking of filling a cat litter tray with ?? Mud? and putting some bait around it hoping for a fox or badger but for the birds would need somthing softer ? to get the imprint then taking the cast using just fine plaster of paris and a section of pop bottle to contain it . With a tray i could then give it time to dry

Adi
04-03-2006, 23:18
Yeah that would work. For your traps use damp sand or sieved lightly compressed soil.