Thank you, Peter. It’s entirely my pleasure to present this build to all who will tune in here. Like “Jim G” said in his Otter build, I just want to give a little back for all that I’ve enjoyed on these forums.
Soooooo, this past week was spent on molding the gunners canopy. Slow and mundane work, which finally resulted in actual canopies molded tonight. For the benefit of the Zealot regulars who may not have seen how I created the cockpit canopy on the forward end of the fuselage, I’ll give the blow by blow for the gunner’s canopy here, which I did exactly the same way. First I created a 3 dimensional template of the canopy from 0.030” thick sheet styrene:
For the first canopy mold plug I used FIMO, which is a Scullpey like clay product that hardens when you bake it. I didn’t have any on hand this time around, so for the gunner’s canopy I used Milliput, a two-part epoxy putty that is kneaded together, then hardens in about three hours. I blobbed it on the end of a brass rod:
Once hard, I started to carve down the blob, using my template as a guide:
Based on the fit in the template, the initial blob came up short so I kneaded some more Milliput and added some make-up areas:
Final shaping and finishing and it looks about right in the jig:
To ready the mold for vacu-forming, I first epoxied the brass rod back into mold (it tore out while I was shaping it):
That rod will help anchor the mold in my machine. Then I filled any imperfections and/or cracks with successive coats of superglue. This creates a hard shell that takes to polishing well. I like to polish my molds as a last step; It shows up those last niggling imperfections (more superglue!) and it seems to make clearer canopies (to me, but I can’t swear to it. Just part of a routine I guess). So once it was as smooth as I could get it, put the plug in my home made vacu-form machine and started making canopies:
Once you get the hang of it, it’s kinda fun. I used the same 0.020” “Vivak” (PETG) clear plastic I used to make the astro dome I related earlier in this thread.
Always good to make extras:
That’s all I got for a week’s worth of work. All that's left is to cut one out and fit it to the model. I needed to make at least two, as I plan to open the top thanks to Elliot’s suggestion. I’ll need one to make the base canopy with the opening, and the second to make the removable portion, like the real deal:
Some useful links:
http://www.dickblick.com/products/staedtler-fimo-soft-polymer-clay/
http://www.micromark.com/VIVAK-PLASTIC-11-WIDE-x-14-LONG-x-020-THICK-PKG-OF-2,7732.html
http://www.milliput.com/home.htm
Mike