I get more emails regarding the making of port molds than all other subjects combined (2 emails about port molds and 1 about ordering Viagra online). So here you go, handed down through generations, an ancient, time honored tradition of diyPorting.com Port Mold Making. Nothing enhances the visualization and illustrates the shape of a port better than a mold.
If you have a little time, and patients, you can make highly detailed molds of most ports for just a little over $2.00 a port, with materials you can find at any hardware store, a Tap Plastics store and auto parts dealer.
The medium I use to form the molds is Permatex RTV Silicon Gasket Maker. While the High Temp is not needed, the red color does photogragh well. Available at most auto parts stores, it retails for about $8.00 a tube. You can get about 4 port molds from one tube. I have tried other silicon caulks, but none worked nearly as well and as fast as the Permatex Gasket Maker.
Tap Plastics Mold Release Wax is very helpfull to ensure a proper seperation of the mold from the port surface.
A smooth surface and a putty knife are used to mix the silicon before application to the port. I use a small piece of melamine and a plastic putty knife.
A small, chisel shape brush, about 1/2" wide with stiff bristles works well to apply the Silicon to the port surfaces.
The most important step to making port molds with the Permatex Gasket Maker, is to mix the stuff really well to expose the silicon to air. This ensures that the silicon will cure evenly and in a timely maner.
I spread the silicon out in a thin swath, then scrape it up onto the knife. Doing this about 10 times will do a good job of exposing all the silicon to air for proper curing. Work quickly, it will start to cure in a matter of minutes.
After applying some mold release wax to the port surfaces with my finger, I begin applying a very thin layer of silicon to the port surfaces. Start at the hardest to reach areas first and work the silicon out from there. If you start applying silicon at the entry and valve seats, you will mess it up trying to reach the inner areas.
The first layer must be very thin. If it is too thick, it will not cure in spots and your mold will be ruined.
After the first layer has cured, about 2 hours, a second and third layer can be applied. These coats are not as critical as the first coat as far as thickness, but a second coat that is too thick will be evident by wrinkles in the finished port mold surface.
Three coats should suffice, and each should have at least 2 hours to cure. When the mold is ready to remove from the port, use a dull screw driver or similar object to seperate the mold from the port surface. Try to reach into the port and seperate all areas before trying to remove the mold.
You may find that removing the mold from the Valve pocket works best. Easy does it, while these molds are surprisingly tough and durable, an uncured area may be present and care in removal may make it possible to preserve an uncured spot.
And there you have it! A pair of highly detailed port molds suitable for the fire place mantle or as a conversation piece for your coffee table.