Diorama Debris is a British company that is taking on the Chinese in the silicone mould business for building components and ground surfaces. Diorama Debris judging from the large number of moulds they offer has been going for some time and while they are not the cheapest supplier of this product type the quality seems to me to be very good. Diorama Debris offers silicone moulds in four scales which are 1/16th, 1/24th, 1/35th and 1/48th scale, this does of course still leave them room to move into 1/72nd scale. The last item in their repertoire is a selection of pigments and the plaster they recommend for use with their moulds. In this review I will be looking at the slate roof tiles mould in 1/35th scale.
This product consists of a single silicone mould which is packaged in a heavy duty polythene bag with a label identifying the product.
I followed one of the guides on the Diorama Debris
website, where there are several PDF file format guides and are well worth reading to help with Diorama Debrisí
moulds and casting in general. Diorama Debris
does not recommend plaster of Paris for use with their moulds as with some being very fine it does not have enough strength when cured, instead they recommend using hard casting plaster. The tools I used should be available to us all and were;
- Disposable plastic cups
- Metal ruler to use as a scraper
- Syringe to measure exact amounts of water
- Pigment for colouring the plaster
- A bowl of soapy water
- Paper towel
- The silicone mould
- Paint brush
- Cup of water to use as a weight
- A piece of Plasticard
The mould for these slate roof tiles is very shallow and so a good quality plaster is required to prevent a lot of breakages and to get the best out of the mould. The silicone mould is of a very high standard as there are no deformations and each tiles detail surface is different, also all of the tiles are evenly spaced and all of the faces of the mould are perfectly level helping in its use.
I began by wetting the mould with soapy water as that makes the removal of any air bubbles easier and was done just prior to mixing the plaster after which you dab it gently with some kitchen towel, this step is also advised in the Diorama Debris
PDF guide . I then measured out a surprisingly small amount of water using the syringe which in this case was 10ml of water and then placed that in a disposable cup, to that I added the pigment of my choice (in this case I used dark green as I did not have any grey pigment and I believed that dark green would allow me to show the slate detail). I then slowly added the plaster to the water until the desired thickness of plaster was acquired, if you add the plaster to the water and do not stir it there are less bubbles trapped in the mix to contend with.
I then poured the plaster slurry into the mould and despite the small amount I made I still had plenty for the mould. I then spread the slurry out using the ruler making sure all mould cavities were filled, I also lightly tapped the mould with a ruler to help remove any bubbles still trapped and help ensure that the slurry fully fills the mould. Lastly after all of this I let the mould sit for a couple of minutes and then placed the plasticard on the mould and placed a cup filled with water as a weight on it (this method is called the glass method and is covered in more detail in the PDF files available on the Diorama Debris
website. I then left the mould alone for an hour to cure to a reasonable hardness, depending on temperature you may need to wait a longer or shorter time. One benefit of using plasticard for the glass method is that you can peel the plasticard from the mould rather than trying to peel the mould from a sheet of glass.
After freeing the mould from the plasticard I left the mould for another hour in a warm room and then manipulated the mould in a rocking motion to release all of the slate roof tiles. Following this method I managed to get all of the slates without any breakages free of the mould. Some of the slats did need a little clean up due to a small amount of flashing being attached to some of them, this was easily freed from the slats with a gentle swipe of my thumbnail. I laid out the tiles how they would look on the roof of a building with a two thirds overlap, and looking at the finished result I was very pleased with the dark green pigment I used giving a pleasing finish. After I had packed away the slate tiles I cleaned the mould; a quick rinse of the mould in water and then patted dry left the mould in perfect condition ready for the next batch of tiles. One thing I am looking forward to is how the tiles will look if they are slightly different colours due to more or less pigment in the water prior to adding the plaster.