Goldberg Cub build, thoughts, gripes, insights etc.
#52
Join Date: Aug 2010
Location: calgary, AB, CANADA
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I have the wing and tail feathers covered and doped now, but need to put the final color coat on them and cover and dope the fuselage and give it the color coat. The weight increase with dope and fabric is not appreciable I don't think so long as the dope coat is not applied too heavy. I have never compared similar planes finished with iron on covering and fabric and dope though. Koverall is relatively cheap but dope not so much any more. It is definitely more time consuming but it is a more durable finish and looks better than monocote type finish.
#53
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Do you have any pictures, love to see what your doing. Are you using Sig products or are you getting the covering and dope from an ultralite supplier?
#54
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And now for something you were not expecting, the beginnings of a wood cowl. This is an experiment into the no paint zone. I'm still working on the no CA zone though.
#55
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Something I did was use the ABS cowl supplied as a mold for a glass one! The plug to pull these has to be pretty smooth so I waxed the INSIDE of the uncut plastic part then sprayed a few coats of PVA letting each coat dry. Then I mixed some cabosil and polyester resin to get into the tight radii at the hub outlet, breather and etc. A few layers of 4 oz cloth was then applied thoroughly saturating it with resin to reduce pinhole probability. Works a treat!
#56
Join Date: Aug 2010
Location: calgary, AB, CANADA
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I can take some pictures tomorrow and post them. I'm using Sig Koverall and dope, always had good results with Sig products although the dope isn't as readily available as it once was
#57
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Arup: If I'm understanding you correctly, you just fiberglassed the inside of the cowl and pulled it out?
swify: I'm assuming Sig has a distributor in Canada so your not importing from the US?
I'm working on ways to use fewer products on my builds. the way I'm looking at is; the fewer chemicals, paints, glues etc I'm purchasing the better. I just want to get away from the chemicals. I was putting this cowl together today with no dust mask and CA glue because I was just trying to get it done and saying to myself, go buy some damn dust masks and stop using the CA. Old habits are hard to change.
swify: I'm assuming Sig has a distributor in Canada so your not importing from the US?
I'm working on ways to use fewer products on my builds. the way I'm looking at is; the fewer chemicals, paints, glues etc I'm purchasing the better. I just want to get away from the chemicals. I was putting this cowl together today with no dust mask and CA glue because I was just trying to get it done and saying to myself, go buy some damn dust masks and stop using the CA. Old habits are hard to change.
#61
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Join Date: Jun 2011
Location: Locust,
NC
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I have the wing and tail feathers covered and doped now, but need to put the final color coat on them and cover and dope the fuselage and give it the color coat. The weight increase with dope and fabric is not appreciable I don't think so long as the dope coat is not applied too heavy. I have never compared similar planes finished with iron on covering and fabric and dope though. Koverall is relatively cheap but dope not so much any more. It is definitely more time consuming but it is a more durable finish and looks better than monocote type finish.
#62
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Swify: You must have better hobby shops in your part of the world then us, Sig dope and it was available in a local hobby shop, what a concept!
Cubcrasher: I'm into a whole new line of sickness with that cowl, a smart man would just get a fiberglass one from Fiberglass Specialties.
Cubcrasher: I'm into a whole new line of sickness with that cowl, a smart man would just get a fiberglass one from Fiberglass Specialties.
#65
Senior Member
Yessir! +1 for Koverall... and Stix-It! Stitts Lite is supposed to have a tighter weave thus requiring less dope to seal the weave.
P-40 DRIVER- yes... after waxing and etc. the styrene plastic cowl the new fiberglass one just pops right out ready to be fitted. Need another one? Why... just repeat the process since you have a 'mold' handy! For the price of a few commercially available cowls you can purchase supplies to do this yourself.
P-40 DRIVER- yes... after waxing and etc. the styrene plastic cowl the new fiberglass one just pops right out ready to be fitted. Need another one? Why... just repeat the process since you have a 'mold' handy! For the price of a few commercially available cowls you can purchase supplies to do this yourself.
#66
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Got home today and my new batteries for my plane and transmitter had arrived. Boring old Nicads but very reliable. I now have them on a form charge and will be testing them over the next few days. Except for weight issues, I can't see any reason to run anything else.
#70
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After a 24 hour 1/10C trickle charge, I'm doing a 1/2c discharge to check for capacity. So far the 4,8V 600 mil amp pack, cycled 665 mil amps using 1.0 volt cutoff per cell. I suspect these are 700 mil amp cells which Futaba is under rating, so my cutoff will be three years or 560 mil amps which ever comes first. Transmitter pack is still discharging but should similar numbers. I'm using a Cellpro Multi4 for charging and a Triton Junior for discharge.
#72
Join Date: Aug 2010
Location: calgary, AB, CANADA
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A few pics of my cub. Need to install the servos and the golden rods for elevator and rudder, then cover the fuselage. I installed servos in the wing for a bit more flexibility in setting aileron differentials.
#74
Senior Member
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Cool old style .90 twin. I would run sheathed steel 2-56 rods instead, less slop and more temperature stable, Great planes makes a good cheap set of theses.
#75
My Feedback: (11)
Here's some pictures of mine. I bought it half built at a club auction, and clipped the STOL tips and one bay off the wing tips, mounted up one of my trusty PAW 40 diesels, and covered it all with red Solartex with white Monokote accents. It flew great on its maiden flight until the needle unwound and the engine quit. Luckily, I had practiced a few approaches with it first, and was in a good position for a deadstick landing. I tweaked the needle a bit to get it to hold a setting, and took off again, only to watch the rudder depart at about 2 feet off the ground. It hit on the nose and left wingtip, breaking the firewall loose, breaking up the cowling, and breaking the horizontal stabilizer. It turns out the DuBro hinges popped loose on both the rudder and elevator. Half the hinges stayed in the rudder, and half stayed in the fin, and the same with the elevator and stabilizer. The sides of the hinges that stayed are very solid, and can't be pulled out. I must have gone wrong with my glue job! Next time I'll pin the hinges.