Model Making: Modelling Fillers

As a model maker, I’ve used a wide variety of different fillers over the years, and as with everyone else I am also on the eternal search for the perfect product! Consequently I will often buy new fillers when I see them, just to try them out. There are a good selection of specialist fillers produced by the various model kit companies. Now to be honest I haven’t really used many of these as they tend to be quite expensive and there are often very similar and cheaper alternative around.

Firstly, of course, there is no one filler that will do everything well. It is definitely the case of choosing the correct product for the material you are working with and also for the task you are looking to use it for. So I am simply going to run through a few I have used and suggest the best uses for them.

Ready Mixed Fillers

Firstly lets have a look at Ready Mixed Fillers, as bought in the D.I.Y. store. Designed for filling cracks around the house, in walls etc., probably the most well known brand in the UK is Polyfilla, however all the different varieties share very similar properties. From interpreting the Health and Safety Datasheet I get the impression that this is more or less a mix of plaster with some PVA adhesive mixed through it.

These Ready Mixed Fillers are not that useful as actual fillers for model making, although I have seen people use them when they are stuck for other fillers! The main thing I use Ready Mixed Fillers for is adding ground work to bases or scenic displays. I find them ideal for this, as the adhesion from the adhesive content helps then stick to most materials. If too much is applied there is a tendency for cracking to occur, but it really has to be quite large amounts for this to happen.

This model is covered in Ready Mixed Filler (then sand on top),

and will be part of a forthcoming blog posting, once the project is complete.

I have recently been buying tubs of Ready Mixed Filler from the local pound store, so it is certainly worth looking around, rather than just heading for your nearest D.I.Y. chain!

A word of warning at this point, there are various types of wall repair filler available, some are described as flexible fillers, these seem to have a more silicone based mix , nearer to a mastic caulking than to a plaster based filler. They have their uses, but I would not consider them for this type of terrain modelling.

Speciality Model Making Fillers

Tamiya, Revell and several other model kit companies produce model fillers, with various different properties. Now, I must admit I have not tried many of these products, but they seem very popular in the model shops so they are clearly worth a mention.

 

I have heard that the two Squadron putties (Green and White) are very good. There is no clear difference between the two, other than the colour, but though chatting with a few people the advantages are as follows. The Squadron Green appears to dry quicker, it is also useful to be able to see the putty once set. Squadron White is reputed to be a finer/smoother texture.

Revell Plasto Putty used to fill the joint between plasticard and an injection moulded form.

I have a tube of Revell Plasto that I have been using recently.It adheres well to plastics and wood, is a nice smooth texture and dries to an off white creamy beige colour. It is a solvent based putty and does have a distinctive smell. I have found it to be very useful for filling smaller gaps,applying it with a knife. Most professional model makers find more economical materials to work with, rather than buying the branded model making materials. This also runs to fillers! Revell Plasto appears to have a very similar consistency and properties to the car body filler Cataloy Knifing Putty from Holts. As Cataloy Knifing Putty comes in larger tubes, and is priced around the same make as the Revell Plasto, I personally would recommend using the Knifing Putty.

 

 

While researching this article I discovered Tamiya Light Curing Putty, which sounds quite intriguing.  I have not gotten hold of any yet, but I’m interested in looking into the uses of a “light curing putty”, so may well track a tube down.

Polyester Fillers

Polyester Fillers are somewhat different to the previous fillers I have looked at. They come as a two part mix, the main filler and a catalyst that once mixed with the filler causes it to set hard.

This stuff has a wide range of uses for the model maker and is an essential item that I always keep on my shelf, ready for use. There are endless different brands available (just do a search for Car Body Filler), but the most well known ones in the UK are Isopon P38 or possibly Ronseal High Performance Wood Filler. Once mixed – the standard proportions are a golf ball sized lump of filler to a pea sized lump of catalyst – they usually set within around 15 minutes, to a hard machine-able finish.

In this photo I am using polyester filler to make a surround for a battery-hatch,

for a lit model that will be featured in a future blog post.

As far as fillers go these polyester fillers are at the heavy duty end of things, they can be messy to work with, and have to be mixed correctly, but are excellent for larger filling jobs, packing models, adding weight to lighter parts. They are also good for building more organic shapes.

I have even seen them used as adhesives for some more awkward materials such as ABS. A professional ship modeller (model ships for the oil industry) that I once chatted with, used to swear by car body filler as the best way to fix his decks to the ABS vacuum-formed hulls of the ships he worked on.

Conclusion

I always tend to keep a tub of Polyester Filler, a tube of Knifing Putty and some Ready Mixed Filler around as they get used on a very regular basis. These are the main fillers that I use while model making, although there are occasionally others (gap-filling Tensol No.12 for acrylic, PVA glue mixed with sawdust for MDF etc.). There are also the epoxy putties like A+B and Miliput and also the sculpting putties like Kneadatite and ProCreate, but I will cover those in depth in a separate article sometime soon…