At this stage of the build, the project gets a little tedious. Sand, prime and fill – sand, prime and fill. This process is repeated over and over until the surface is smooth and the two halves join in the center.

Spending time at this stage pays off in the end. Remember that every flaw that you are too lazy to work out of the plug at this point will have to be worked out on every piece you ever make with the final mold. In other words, you can fix a flaw once here, or you can fix it on every piece you ever make, maybe 100 times. Do yourself a favor – Fix It Now!

It is at this time of a plug build that I like to apply a nice thick coat of heavy fill automotive primer from my air gun. This primer will fill all of the remaining imperfections and it can be fine sanded, polished and prepared for the actual molding of the plug.

At this point, I believe that I am done with the helicopter plug. Now is the last time to stare at it and make sure it is right before molding. As you can see in the picture, the two halves of the plug are clamped together so that I can check the alignment. I have already painstakingly aligned the two halves but now I am reaching the point of no return. I spend a good bit of time looking at the alignment of the two halves and at the plug itself.