Ernge mold
by Jake on Jun.11, 2007, under One Meter
I did manage to squeeze out another mold last night. This time it was a mold of the finished rear deck so I can more easily reproduce them in the future. I tried, for the first time, brushing on the gelcoat instead of going through the process of spraying it. It was certainly faster, but it was very difficult to get a smooth thick coat. If I brush it on again in the future, I will probably plan for two small batches and at least two coats in between opportunity for the gel coat to tack up. I also tried, for the second time, to apply PVA over a primered surface. Because this mold was mostly going to be an “outy”, I figured I wouldn’t spend too much time trying to get the finish right on the “inny” surface of the rear deck and figured that with the wax and PVA, release should be relatively easy. It will be easier to wetsand the mold surface and polish it to a really smooth sheen since it is more male shaped. This worked well except that I still had a little difficulty separating the mold in the areas that were difficult to buff the wax. I think if I had applied a smoother finish coat of paint instead of the primer, the PVA would have worked a little better. You don’t see primer in that photo because I wiped it away with acetone because it was mottled from sticking to the PVA in places. Anyway, there it is, the mold ready for the next iteration.
What’s next? Well, I’m going to probably work on the radio tray and laying out some of the radio gear and some of the control lines. I’ll also finish up the mast rigging by creating the jib boom and working out the geometry of the jib connection points on the hull. I haven’t figure out exactly how I’m going to reproduce the NACA foil shape for the rudder…perhaps I’ll get thinking on that soon. However, judging from the puddle of water in our laundry room at the moment, it looks like I’m going to be installing a water heater tomorrow evening.
I’m still a bit delayed with the lead mold as my friend who does the CNC programming is on vacation at the moment. Just before he left, he was trying to get the mill run time down from the 32 hours per mold half predicted on the first programming pass! (I think the resolution was a bit high)
PS…by the way, that double fan in the window ($9.99 at Big Lots) shown behind the orange mold is absolutely terrific for evacuating the obnoxious vapors and dust from all this composite work.
