I finally got back to my Static Scale 3-blade Hamilton Standard propeller for my upcoming Top Flite Corsair project, and I finished off the prop hub detailing! This is fairly easy but the results, though not museum scale quality, are more than acceptable for stand off scale. Here’s what I did.
(Above) this is where we left off, with the basic hub and nose cone smooth and ready to be painted. Of course you could go ahead and do just this much work, and go right to paint and it would look more than acceptable. But since I wanted to add just a little more “eye candy”, I added the prop hub assembly bolts and the blade adjustment bolts. I think these are what make the hub so interesting to look at. Note, that this is also a good time to ream out the center hole to properly match the output shaft of your airplane’s engine. I chucked my 10mm prop reamer in my drill press and used a slow speed to enlarge the hole. It should be a slip fit. Being the inside is wood, you do not want a very tight fit. If the humidity goes up, the wood will swell and make it difficult to slip it in place or remove it. A little loose here is a a plus.
(Above) Depending on the number of blades your hub has, you’ll add short bolts and tubes between each blade. For 3-blade hubs, there are two bolts and for a 4-blade hub, only one is in between each socket. I used 2-56 cap head screws and some brass tubing roughly the same diameter as the cap-head bolts. The assembly bolts and tubes are cut about 1/4-inch in length and the blade adjustment bolts and tubes are about 3/8-inch in length. I use the K&S Tubing cutter for this as shown above. I cut the tube section just a little shorter than the bolts so just one or two threads are exposed on the aft end.
(Above) Use a Dremel Moto-Tool with a flat cutoff disc, and cut two notches into the raised web to fit the hub assembly bolts and tubes. This is a cut and fit operation.
(Above) Place each bolt/tube in the notch and center it with the web. Use thin and Thick CA (I use ZAP) and glue them in place. Mist a little kicker over them and then add another application of thick CA and kicker. This fill in any voids and builds a small fillet around the tubes. Now do this for the other two web sections. Before gluing the tubes to the hub, add a small drop of Zap to the bolt and glue it into the section of tube.
(Above) Now grind small flat spots on the sides of the sockets at the ends of the webs. This is where the longer blade adjustment bolts/tubes will be glued in place. Again carefully apply Zap CA and kicker to make a small fillet/glue joint to hold all the tubes in place. All the tubes should be straight and centered on the raised web.
(Above) After all the hub bolts / tubes have been glued in place, go over the entire hub assembly and double check for imperfections and cracks in the putty. Fill and sand as needed and then degrease the whole thing with some alcohol and let dry before painting. Here, the hub has been primed with some white enamel primer. No sanding is required if you did your homwork and everything is already smooth. The primer coat will also show any other defects requiring further attention. Apply a second and final coat of primer and let dry overnight.
(Above) Here’s the final result. I shot two coats of “buffing” silver onto the main hub assembly and after two days I lightly went over everything with a soft piece of Tee-shirt cloth. This really gives the silver a “cast aluminum” look. I also cleaned, primed and then shot with two coats of bright red onto the resin cast nose cone after I glued the hex bolt into the front. After everything has dried, a little weathering with some dark over spray to help pick out the details and it will be done.
Stay tuned for the next and final step of mating the blades to the hub! It all looks great now, but it doesn’t even compare to what the final appearence will look like when we hang our Hamilton Standard 3-blade prop on the front of the new Top Flite F4U Corsair!
To see how we finished this series and fitted all the parts together, click this link: http://www.modelairplanenews.com/blog/2012/06/01/static-scale-hamilton-standard-3-blade-propeller-part-7/
(To see the whole build-along series thus far, click this link: http://www.modelairplanenews.com/blog/2012/04/26/scale-3-blade-propellers-building-a-ziroli-static-scale-kit/