Duplicating Zimmerit on German Tanks
by Phil Novak
The Germans introduced Zimmerit in 1943 to cut the losses of armored vehicles to magnetic mines. It is a cement-like substance applied in two coats during the production of the vehicle. Made of Barium Sulfide and a few other materials, it was corrugated to cut down on the weight of the already heavy vehicles. It is this corrugation that poses the difficulty of reproduction in 1/35 scale.
Zimmerit is a very eye catching detail to add to one of your models; however, many modelers skip projects that require Zimmerit because it is difficult too apply. Its ways of application are numerous: Zimmerit Sheets, putty, and the hot knife method are used with great success by many modelers.
Cavalier Productions has come up with thin resin sheets that you glue on the surface of the plastic to reproduce the unique texture. To start, get a sharp X-Acto number 11 blade and cut the desired section out of the sheet. Then comes the ugly part: you have to file off any surface detail on the model so that the sheet will sit properly. Use an emery board for the smaller stuff such as rivets and an x-acto blade for the big stuff. Next, carefully test fit it on the model to be sure that it is roughly the right shape. Don't worry if it doesn't give an exact fit, as they are made larger then necessary in order to cover the whole section. When you are satisfied with the fit, apply CA glue to the edges of the sheet and put it in place. After the glue has dried take your #11 blade and trim off the excess. Finally to finish off, use an emery board to file it flush with the edges of the vehicle. Paint as usual.
For the most part I didn't have a whole lot of trouble getting the stuff on (It's a lot easier than the putty method) and the final result is great. The things that I didn't like about it were the $19.95 price tag and the tendency for the replacement parts, such as the rear panel on a Pz.Kpfw. IV, to be warped. But for the most part its very nice and well worth the effort.
Another method is the putty method. There are many variations of this method, and be open to ideas when trying to do this task. One way of applying the putty is to start by thinning some body putty down with plastic cement. Once you have it to a honey like consistency, spread it on the model and let it dry for about 5 minutes.
Then go back with a small screwdriver and push in the corrugations using an upward stabbing motion. This will dry nice and hard and should look perfect when painted. It is also very close to how the Germans actually put the stuff on the real thing.
A variation on this technique is to start off by putting a small dab of putty (Squadron's green stuff will do nicely) on one side of the model. (As shown in this photo of Joe Marcal's Tiger).Then take an old razor saw blade and use the teeth to create the corrugated texture by dragging it across the surface of the model. Also jog the spreader sharply every ¼" to break up the corrugation. Remember to only work one part at a time and use a screwdriver to texture any unusual areas. That's pretty much all there is to it, but it's a lot harder then it sounds.
Another way to reproduce Zimmerit is the hot knife method. This King Tiger tank, built by David Clarke, employs this method. He used the standard #11 tip and very carefully etched little grooves into the side of the model, working around the smaller parts like tools and gun mounts. This gives the modeler utmost control and lets him work any pattern that he is required to do. Like anything else in modeling it takes a lot of practice to get it perfect, but it still is a valuable way to achieve that perfect Zimmerit finish.
Again, try methods until you find the one that works right for you.
Photos by Phil Novak. Scans by Brian Hirsch