Balsa USA Super Cub Build
#176
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RE: Balsa USA Super Cub Build
Tony, Your covering came out looking really nice. What color / colors are you planning for it and what is going to be your paint process?
Keep up the good work,
Keith
Keep up the good work,
Keith
#177
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RE: Balsa USA Super Cub Build
Datona white and Pontiac red. Stits covering, Poly Brush, Poly Spray, Ranthane top coat. According to Chip at F&M Ranthane is easier to spray than Aerothane for the novice and it is approved by the FAA for full scale use.
#178
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RE: Balsa USA Super Cub Build
I added several gromments and reinforcements per scale fuselage drawing. I made the gromments out of 1/64" aircraft ply. For the front stablizer cover I had added 1/32" aircraft plywood plates to accept the screws for the cover.
The last photo shows the area I'm talking about. I believe the builder of the plane on the last photo used iron on type fabric and was able to stick the fabric to the plates provided in this area. Since I when the envelope method, I ended up with about 1/4" gap between fabric and plates at rear most area. I consulted the Piper drawings and found out attachement plates were doped to the fabric covering so thats what I did.
The last photo shows the area I'm talking about. I believe the builder of the plane on the last photo used iron on type fabric and was able to stick the fabric to the plates provided in this area. Since I when the envelope method, I ended up with about 1/4" gap between fabric and plates at rear most area. I consulted the Piper drawings and found out attachement plates were doped to the fabric covering so thats what I did.
#179
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RE: Balsa USA Super Cub Build
Most of the gromments require fabric reinforment after atttachment. Stits recommends this fabric be pre-shrunk to 275f. I made a frame out of scrap 1x2 material, glue a peice of fabric to the frame with Polytac, shrink with iron set at 275f. The resaon for pre-shrinking is that once the fabic weave is filled with Polybrush and tapes applied, you can heat smooth the covering with an iron set at 225f, the Polybrush softens at less than 225f, so you can iron down imprefections in the reinforcement without worry of shrinkage since the fabric on the airframe is shrunk to over 300f and the reinforcements are shrunk to 275f. This is one of the advantages of the Stits process on full scale airplanes, less sanding. I hope this makes sense?
#180
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RE: Balsa USA Super Cub Build
Thats the same process I will be using on my Great planes .60 J-3 turned Super Cub. F&M is near where I live so that was an easy choice. Here are a few full scale J-3 pictures of the areas you are refering to. You may already have some but what the heck, more never hurts [sm=regular_smile.gif]
BTW I like the V8 Vega, Dont see many around any more. Is that an LT-1? (I build and paint street rods for a living)
Keith
BTW I like the V8 Vega, Dont see many around any more. Is that an LT-1? (I build and paint street rods for a living)
Keith
#181
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RE: Balsa USA Super Cub Build
LT1, 1996 firebird donor, I bought the donor about 9 years ago at a salvage sale, 10,700 miles on drivetrain. Nice photos of the cub. Thanks
#182
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RE: Balsa USA Super Cub Build
I built the fixture to support the wings while painting, it supports both wings and allows turning without touching the wings. I'm currently putting the finishing touches on the flaps, ailerons and rudder so that I can cover them. Once this is complete, I will be ready for the first coat of Poly Brush, then the tapes will go on. Slow progress, but progress not the less.
#183
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RE: Balsa USA Super Cub Build
I finished preparing the alierons, flaps and rudder for fabric and discovered that I'm out of Polytack so they will have to wait until I can get more. I decided to work on the pulley covers for the top of the wings. I made a plug out of scrap work, 1/8" plywood base, 1/32" outline, and 1/2" balsa block sanded to shape, a couple coats of clear enamel. Once dry I will final sand and spray on the final clear before laying up the mold.
#184
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RE: Balsa USA Super Cub Build
Hi Tony,
I'm hoping you can take a few minutes to help me out. I've just bought a very used Balsa Usa !/4 Scale Cub and I'm looking for factory recommended control throws and C.G. location to help me refurbish this plane. Also wondering how others that have this plane do their field assembly? Do you lay it on it's back to make it easier to install the wings and struts?
Thanks for your help.
Jay
I'm hoping you can take a few minutes to help me out. I've just bought a very used Balsa Usa !/4 Scale Cub and I'm looking for factory recommended control throws and C.G. location to help me refurbish this plane. Also wondering how others that have this plane do their field assembly? Do you lay it on it's back to make it easier to install the wings and struts?
Thanks for your help.
Jay
#185
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RE: Balsa USA Super Cub Build
jay hi I am building one as we speak the assembly manule states elevator 1" up and down . rudder 1-1/2" right and left. ailerons 3/4 " up and down. with differential ailerons 3/4"up and 3/8" down. the CG is measured from the leading edge of the wing back a distance of 4-1/16" i spoke to a tech at busa and about the wing attchment and have decided to modify it with some hard wood in the top of the wing to accomidate small socket head bolts that go into the wing dowles so i dont have to try to stick my hamhocks in to the cabbin since i will shurly break the door or window trying to get the wing bolts in place i hope this helps leo
#186
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RE: Balsa USA Super Cub Build
I have a 1/3 BUSA scale J3 Cub kit and was wondering: Can I convert this to a Super Cub? I am more than willing to purchase extra kits as required to make it happen. I'll need a flap hardware kit, a new cowl, and probably new landing gear. Is there anything else? Thanks for any guidance here.
#187
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RE: Balsa USA Super Cub Build
The BUSA J3 fuselage is different. The Super Cub sides are near flat while the J3 tapers inward. See photos of the Super Cub and compare to your plans. The wing rib spacing is different on the Super Cub. The J3 has uniform rib spacing while the Super Cub is somewhat random in it's spacing. I'm sure both of these differneces could be resolved during construction. The gear is the same as far as I know. BUSA sells the scale aileron kits at a reasonable price, need two for the flaps and ailerons.
#189
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RE: Balsa USA Super Cub Build
Hi Mongorex,
Yes, that's great information, thanks a lot. Two other points are wing dihedral measurement and the location of the landing gear either from the firewall or the wing leading edge off the plans. This clean up has turned into quite a project but it's fun. This will be my first giant scale plane. My other new plane is the E-Flite Taylorcraft electric...I could almost mount it inside!!
Jay
Yes, that's great information, thanks a lot. Two other points are wing dihedral measurement and the location of the landing gear either from the firewall or the wing leading edge off the plans. This clean up has turned into quite a project but it's fun. This will be my first giant scale plane. My other new plane is the E-Flite Taylorcraft electric...I could almost mount it inside!!
Jay
#190
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RE: Balsa USA Super Cub Build
Hi Tony. Just started reading your build thread, and its very interesting. Especially the Jigs that you have made up. Never in a million years would I have thought of some of the jigs you are useing.
Beautifull work too. I am looking farward to seeing the finished product. Puts my lil ol sig 1/4 cub to shame thats for sure. Someday when I build a new one, I will definatly be looking back on this thread for ideas. Keep up the good work.
Beautifull work too. I am looking farward to seeing the finished product. Puts my lil ol sig 1/4 cub to shame thats for sure. Someday when I build a new one, I will definatly be looking back on this thread for ideas. Keep up the good work.
#191
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RE: Balsa USA Super Cub Build
hi jay the meaurment from the firewall to the first wire of the landing gear is 8 1/2" the way i obtained this was to place a straight edge runing along and past the front of the fire wall on the plans and mesured back to the landing gear wire on the plans at a right angle mine has a notch in the plywood landing gear plate to receve the wires if it would help i could take a photo of the prints and post them let me know. as far as the dihedral goes the directions say to set the root rib tiped towards the wing tip 1/32" in other words slant or tip the top of the rib tords the tip of the wing.
goodluck and let me know if you have any more questions LEO
goodluck and let me know if you have any more questions LEO
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RE: Balsa USA Super Cub Build
Thanks again Leo, that will help a lot. The plane came with floats that are ready to mount as well. I'll probably start with them as the rear wire mounts are already drilled and then see where the front wire lands and base my wheel gear on that starting point. The measurement will help to assure I'm in the ball park. I guess the best thing for the diherdral would be to assemble it and check dimensions at the root and tip and make sure they match for both wings. This plane was flown A LOT before I bought it, but I've never witnessed it. It has also been crashed a few times and I wanted to make sure things were close to designed. I have it pretty well taken apart and I think I'm ready to start putting it back together with new electronics and a refurbished motor and fuel tank, and new landing gear. Here are a couple of pictures.
Jay
Jay
#193
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RE: Balsa USA Super Cub Build
While waiting for the Polytack to arrive I decided to finish off some the interior parts and pieces, all control parts were painted with semi-gloss black paint, the floor got several coats of clear enamel, seat cushions are ultra flat black, and the elevator trim handle got that tacky spray chrome paint. All the bolting on the control sticks are hex head fasteners to as is the full scale. Those all metal 4-40 locking nuts are really neat, looks much better than standard plastic version, somewhat pricy through. My camera is a fixed lense and close up quality is poor.
#194
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RE: Balsa USA Super Cub Build
I'm pleased with the pulley cover, second one's in the mold. Tonight I might mount the engine and figure out if any changes will be made to the exhaust. Right now the stock exhaust is dual outlet Johnson mufflers, a single will look better.
#195
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RE: Balsa USA Super Cub Build
I starting looking over the options for the exhaust system. The full scale exhaust pipe is located right inside the cooling air exhaust opening as seen below. The outlets for the Johnson mufflers are loated much closer to the propeller. To use these I would have ended up two holes in the cowl that would have intersected a rather busy area of the cowl. The decision to modify the exhaust was a good one.
#196
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RE: Balsa USA Super Cub Build
Stated by laying out area where the exhaust will exit. This modifiaction will improve another area that I didn't care for anyway. As designed the cowl sides back onto the fuselage about 4", the area where the air exits on the bottom is completely filled with fuselage. On the full scale, the fuselage sides end at the cowl and the cowl takes over from there, when you look up into this area you would find a black hole filled with exhaust pipes and muffler. I had originally planned to paint this area black under the cowl. If I were to built another Super Cub, I would move the firewall back to end of the cowl leaving only 1/2" or so over lap, maybe no overlap. Then this area would be used for a fabricated muffler.
Measure twice and hopefully cut once. I hacked off the outlets on the Johnson mufflers so there's no turning back now.
The exhaust system will be constructed from 20 and 22 mm K&S tubing. The connection at the mufflers will be a mechanical bolted connection. Of couse as all things on this build subject to future revision.
As luck would have it, Brown delivered the Polytack this afternoon, now what to do, continue with the fuselage, or finish off the wings?
Measure twice and hopefully cut once. I hacked off the outlets on the Johnson mufflers so there's no turning back now.
The exhaust system will be constructed from 20 and 22 mm K&S tubing. The connection at the mufflers will be a mechanical bolted connection. Of couse as all things on this build subject to future revision.
As luck would have it, Brown delivered the Polytack this afternoon, now what to do, continue with the fuselage, or finish off the wings?
#197
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RE: Balsa USA Super Cub Build
Tony, everytime I see your progress it seems to mirror what we are dong with the full scale L-4. I help on installing aileron cables and fairing and come home to see you've done the same. Its kind of neat and makes me appriciate all the work that your doing. Here are a couple more pics for you in the areas that your working on. (Also one of the shop, the fuse hanging up is a super cub, the other planes are all L-4's)
#198
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RE: Balsa USA Super Cub Build
Keith,
Keep those photos coming, great reference for anybody building one these models. Your lucky man to be able to work on the real deal along with the models. Can you share any experience with the Polyethane aircraft paints as far as application? I to have spent so time with automobile paint and I understand the aircraft paint has less fillers and subject to runs? Chip at F&M recommeded Randthane which I will be using. Any input would be helpful.
Keep those photos coming, great reference for anybody building one these models. Your lucky man to be able to work on the real deal along with the models. Can you share any experience with the Polyethane aircraft paints as far as application? I to have spent so time with automobile paint and I understand the aircraft paint has less fillers and subject to runs? Chip at F&M recommeded Randthane which I will be using. Any input would be helpful.
#199
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RE: Balsa USA Super Cub Build
The last piece of the airframe is getting covered, the rudder, next spray one coat of Poybrush, then the taping and stiching will begin. I did one thing differently on the rudder and ailerons due to the long controls, I per-cut the slots in the fabric using a solder iron before hand. Mark the location, fold the mark over the corner of the workbench, melt the slot away, no snags to deal with. The instructions have you cover over the protrusions, lightly shrink the fabric, paint the area with Polybrush, then cut the openings as can be in the last photo of the hinging. Once trimmed, them the fabric is final shrunk, I used this for all but the lower aileron horn and rudder horns.
#200
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RE: Balsa USA Super Cub Build
Tony, Yes what you have been told is true. My experience with the aircraft paints are that they are much "thinner" that automotive paint being that they do not have the solids that an auto painter would be used to. If you have experience shooting clear then you should be ok, as the colors shoot about the same way and will run just as easy. I would suggest shooting a test panel to get your gun and air pressure set right.
On my Super Cub I am going to cover and fill the weave with polly brush and polly spray then paint with House of Kolor and Dupont base coat / clear coat paints (Pearl white and candy apple red)...
Keith
On my Super Cub I am going to cover and fill the weave with polly brush and polly spray then paint with House of Kolor and Dupont base coat / clear coat paints (Pearl white and candy apple red)...
Keith