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Graupner Optimist re fit

Forgot I had the Optimist to re-do so I'll do a short blog on what I'm doing. I had already re-fitted the stays with solid stainless fishing trace as the original wound wire stays had frayed and had nasty sticky out bits. I had also re-joined the cabin roof which I had cut behind the mast for R/C and battery access (once assembled the model had no access to the interior and involved removing all the stays sheets and mast to get at anything,- about 10 mins work!) Now with long lasting LiPos there will be no need to remove the top for the whole day. I have two 'El Cheapo' winches to fit,- one for the jib and one for the main. Not sure how long they will last as they won't even center properly and sit there and hum most of the time. The alternative is a very expensive modern winch, around $600 or maybe a winch servo arm type, (still quite expensive). I have ripped the rudder and shaft out as it had completely seized up over the last 40 years and was spinning in the hull, (having broken the epoxy) I've made a new shaft and bushes to go back in, and will be adding a lower (skeg) and upper (deck) bush as the original had none and just sat in a hole in the ABS skeg, and the shaft tube was just held by 2 to the inside of the hull. I am strengthening all this up, and the top bush will now support the shaft where it comes through the deck to stop any flex in the ABS. It was a very nicely made model in its day but ABS was the wrong material to make it out of, considering the weight of the keel required. If you pick the model up on its side, the hull flexes, so I might glass the inside for a bit more strength as it's getting old and probably a bit brittle in that area, (as long as polyester resin won't distort the hull) The rudder shaft goes through the deck, through the shaft tube and into a brass tube which is epoxied into the rudder blade, and through to the bottom bush of the skeg. The shaft and blade tube are drilled through before the blade tube is epoxied in place. Shaft and rudder blade are then assembled as one unit into the hull ( shaft going through everything) with all the bushes epoxied in at the same time to line them up The shaft and blade are then pinned in place through the pre drilled holes. This time I'll fill everything with grease to hopefully stop it seizing again. Might use a small stainless split pin to lock the blade and shaft as it might be easier to remove. This design also was not a brilliant way of doing the rudder, and prone to corrosion inside the blade tube. I have also re modeled my modelling room as a complete area, (was getting sick of working between rooms. Have put both 6ft tables in so now have more 'bench space'. Now to get rid of some planes!

5 years ago by jbkiwi