Thanks Dave & Curtis for stopping by and asking your questions. Remember this is a hobby where people share how they do different things...that is how we all improve...and no matter how "good" you think you are, you can always learn something new!
First up is Dave's question on what the base is made from.
If you notice the base has two layers of foam. The lower layer is a 5 inch (12.7cm) diameter by 1 inch (2.57cm) thick large cell hard foam that I picked up from Michaels Arts & Craft store. But any kind of foam core can be used. The top layer is some scrap packing foam from a furniture shipping box and is softer then the first layer, though this really doesn't matter the two layers can be made from the same type of foam, I just had these two on hand so I used them.
After I glued the two layers together and carved the top layer to its basic form I applied a thin covering of Celluclay on the sides. Celluclay is a paper mache product that is easy to use and can be picked up at most art and craft stories. When I applied the Celluclay I tried to make is as smooth as possible. Once this thin layer was dry I sanded it smooth as possible. Next I applied a thin coat of Drydex Speckling from DAP that I picked up at either Homedepot or Lowes. This will make the side vary smooth once sanded when dry. Once all the basic ground work was added I primed/sealed the entire base with Rust-Oleum Specialty Camouflage Flat Black paint fro a spray can . I then painted and detailed the ground work. The last step was to apply several coats of Vallejo satin varnish to the sides.
I hope that kind of answers you question Dave but if you have more please ask.
And now for Curtis's question about what the red stuff on the suspension and turret are....Actually they are two different materials
The stuff on the suspension is Liquitex Blended Fibers with brick red craft paint added to it. The Liquitex Blended Fibers is an acrylic product and is intended to add volume for a heavy layer of Mud in and around the suspension. Since heavy tanks travel through the terrain and not "Over it" I wanted to have a heavy accumulation of mud on the lower parts of the Sherman. The Liquitex Blended Fibers just helped in that process. The Brick red paint was so that I could see where I applied the blended fibers as it dries mostly clear thus making it hard to see with my 48 year old eyes to see
Liquitex Blended Fibers can be picked up at a good arts and craft store.
The red stuff on the turret is an automotive Glazing & Spot Putty. I used this to lessen the casting effect that I was not happy with on the turret (kind of over did it with a motor tool). I only used this Auto Putty because I had a tube of it laying around and wanted to see how it might work in model building. I think any good model putty would have had the same effect.
I hope that helps out Curtis, let me know if you have any other questions.