This DVD is sold by Freeman Mfg. & Supply Co. and deals with how to make various types of molds. As I was looking into making my own molds at the time, this DVD was very appealing. The DVD comes free with their sample kit, or can be purchased separately for under $10.00. There's lots and lots of details on the DVD. I won't go into every little details for this review as it would make it very long and boring. Introduction This chapter of the DVD pretty much tells you what to expect out of the DVD itself. Mold making is an art form that has been around for ages and has become easier in modern days due to the availability of new materials, such as rubbers and epoxies. The Basics There's quite a bit of useful, practical information in the chapter for the beginner. First, it talks about masters and CNC machining. This last part obviously not intended for the mere hobbyist. Preparing molds is crucial or the part will stick to the mold. Freeman suggest 3 of their own products which go on the part in the following order : 2 coats of wood and plaster sealer (for wood/wax), 2 coats of wax, 2 coats of PVA release, and one more coat of wax. To ensure the molding and casting agents function properly, weighing and mixing is key. The DVD will show you how to calculate volumetric yield to ensure you have the correct amounts and to avoid waste. Some products need mechanical agitation prior to use, the DVD will show you which. An interesting "3 cup procedure" is shown which is used to mix agents which have a 1:1 ratio. First, poor 1 portion of each into a cup. Poor one cup into the other and mix. When the mixing is complete, transfer the mix to a fresh cup. The cup you mixed in earlier has material that wasn't fully mixed on the side of the cup, this could cause problems. Using the third, fresh, cup takes care of this. Some agents need vacuum degassing, this technique is also shown on the DVD. For me, it was more interesting to see which products required degassing, so I could avoid them. I didn't want to have to deal with degassing. Casting This section of the DVD shows the process of making a urethane or silicone rubber mold and casting the part. The differences between the two are also discussed. The procedure for each agent is shown step-by-step, in great detail. It is an excellent how-to. After the basic molds, more advanced molding techniques are shown, such as complex molds, multiple cavity molds, casting thin-walled parts, and surface casting. Laminating Videos This chapter will show you how to make molds with fiberglass and epoxy. This method is cheaper than using rubber and is well suited for mid-sized parts/molds. The general technique is demonstrated, including the use of gel coats. If you've never done a fiberglass layup, this gives you all the info you need. Large molds which need to be strong can take a lot of time. To speed up the process, Freeman offers a paste laminating system. First, a thin fiberglass mold is created. next, the paste is applied, followed by more fiberglass cloth. This results in a thick, strong mold with a minimum of fiberglass layup work. Next is their Repro laminating system, which I found very interesting. Instead of using fiberglass, this method uses fiberglass strand. This makes it easier for use with detailed molds. It also appears to be less time consuming and easier than the traditional fiberglass layup method. Finally, glove molding is discussed and examples are shown. Here, a soft mold (glove) is created around the part, which is backed up with a strong mold shell. This gives you the benefit of a rigid, strong mold without any of the disadvantages. Products The final chapter goes over some of the Freeman products. Usually, I may have a problem with a DVD I paid for being a lengthy advertisement. In this case, the information is presented in a way which tells you what will be best suited for various applications and it doesn't come over as salesman-like at all. If you're planning to make your own molds and have little to no experience, I'd strongly suggest picking up this DVD.
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