I’ve always wanted to try plaster casting animal tracks. I don’t know why, it just seems like an interesting thing to do. I suppose it would be a useful skill if I ever come across a really rare track of say, a bigfoot or puma. Neither is very likely in Bedfordshire, but you never know. Anyway, today I gave it a go.
There isn’t much information on the internet on how to make plaster casts, so here’s a guide if you want to try it yourself.
Firstly, be prepared. I used plaster of paris (available from the Hobbycraft chain of stores) but I’ve heard of people using decorating filler instead. You’ll need plaster, water, a bowl to mix it in, and something to stir it with. You’ll also need some way of making a dam around the track to contain the plaster. For this I used strips of cardboard and rings cut from a plastic bottle.
A lot of these things could be improvised in the field, but I wanted to be sure that I had everything I needed, and I wanted it to be clean, so I took it with me.
The next step is to mix the plaster. I feel that this is a bit of an art and may take some practice. Put the plaster in the bowl first. It is best to add a little bit more than you think you’ll need.
Now add the water and stir slowly.
The aim is to get a smooth and even consistency. Add enough water to make it slightly runny. You’ll need to stir it to get all the lumps out, but don’t stir it too vigorously or you’ll introduce air bubbles that may spoil the cast.
Next, put a dam around your track. Here’s one made from a strip of cardboard clipped together around a deer track. Push it into the ground slightly, but be careful not to distort your track.
Then add the plaster. This dam is made from a section of plastic bottle and is around a badger track.
Pour the plaster in carefully so it runs into all the little nooks and crannies of the track, and don’t pour it in from a height in case you damage the track.
Leave for 30 minutes or so until the plaster is hard, and then it should be ready to carefully lift out. It’ll bring some soil with it. Leave this soil in place for the moment.
Wrap the cast carefully and bring it home. You’ll need to remember to bring a lot of plastic bags, as you’ll need to wrap up your messy bowl too. If you’ve used a plastic bowl you can easily clean this when the plaster has dried by flexing it to break off the plaster.
After a couple of hours you can clean the track. Brush it softly under the tap to get the loose soil off it. Don’t scrub, or you risk damaging the detail. The cardboard dam was easy to remove, but the plaster stuck to the plastic one. Unless you can grease the plastic dam somehow it may be best to use cardboard.
And there you have it – a permanent record of the track to study at your leisure.