People are always asking me about ARF (Almost Ready to Fly) models. There are some impressive ones around, and these days most of them fly very well. (That was not always so.) I don’t pay a lot of attention to them because my “thing” is building the airplanes I fly. However, recently lots of experienced model builders have taken to “scaling out” interesting ARF’s…stripping off the plastic covering, correcting structural features that don’t match up well with the reference drawings, maybe adding extra detail, and then finishing with a more realistic fabric-and-paint covering. I got a chance to do just that not long ago, using the SIG Waco SRE ARF, a 1/6 scale ’30’s era cabin biplane with a wingspan of 69.5″. (There’s a good possibility that a print article detailing my scale-out may appear sometime soon.)
The Waco has turned out to be one of my favorite airplanes…but…a couple of weeks ago I had it out at a nearby club field when one of the main wheels fell off in flight. The resulting landing on one remaining wheel and a stub axle wasn’t pretty, and tore the entire landing gear assembly out of the fuselage. No big deal…I’ll fix it, make sure the wheels stay on in the future, and get it back in the air. Then, listening to some of the comments from the guys who had been watching, I realized my Waco began life as an ARF, that most of them owned and flew ARF planes themselves, and that that they could not imagine how I was going to repair the damage.
So…here’s an inside look at what I did. No big deal for an old-timer, but really good stuff for newer modelers to learn about.
This is the airplane before I got into trouble. Here it has wheel pants as per the kit. I removed them and added larger wheels for flying off rough grass fields. The trouble came along when I didn't get the attachment of the new wheels to the axles right.
The entire main landing gear and its mounting plate were broken loose.
The built-up fairing over the gear mount was pulled apart.
AND...the aluminum auxiliary (rear) landing gear struts were bent and their internal attachment plates were broken loose.
The 1/8" plywood plate built into the bottom of the fuselage to hold the 1/4" ply main gear mount in place came apart and tore loose.
The main landing gear mount was intact. but the internal plate was junk, and the rear struts were twisted badly. The main strut came out OK.
The 8-32 blind nuts that accept the four landing gear mounting bolts were attached to the internal plate. I stripped them out, cleaned them up, and threw away what was left of the 1/8" ply plate.
I wanted to do exactly this. By the time I got around to looking for the kit they were gone. Its not like the old days when a kit would be around for a long time. I have built the sterling SRE and flew it to death. A friend is now resurecting it. Wacos are high on my list of favorite birds.
Marion
Marion,
Check out Sig again…one of the guys in our club here says he just purchased a new SRE ARF from them. BTW…watch FLY RC Magazine for what should be a two part article on my original scale-out of this kit.
Bob
Hi, You mention flying the Sterling S.R.E.
Was it nitro power?
If so can I ask what power you used and what did the finished plane weigh. The kit included cowl is for .40 size motors, but the plane looks to be finishing at heavier than that. I’m thinking a a 60size motor but the cowl is then too short. Any suggestions are most welcome.. I’m wating for a reply from Fiberglass Specialties on their cowl depth.
Thanks
Marion,
I hope I didn’t manage to give out the wrong info…the WACO SRE worked with is the SIG ARF job (no longer on the market as far as I know). This is a significantly bigger airplane than the Sterling and I’m not familiar with it. I can offer you two suggestions. One, Sterling kits tend to come out HEAVY as designed, so be ready to do plenty of sanding and trimming. Second, based on all my experience with E-power scale jobs,work “backwards” from the propeller to determine motor size. Figure out what the scale prop diameter should be for your model and choose a motor that will turn that one safely.
Bob
Bob,
I just acquired a NIB kit, in yellow. I looked over the instruction and found nothing about how the wing wires can be removed for transport(other then unscrew the brass pieces the top or the bottom wing). It seems to me that the designer must own a VERY BIG car!! Can you tell me how do you handle this problem? It seems to me I would need to redesign the attachment hardware to make a built-in quick release, using a pin or a clevis, to make field assemble process a bit less troublesome.
Brian
Brian,
I agree with you…there is no practical way to quickly disassemble the SRE for transport . I guess you could say I cheat, because I have a big enough car (Saturn Relay van) to load the model in one piece (but only with great care).
It shouldn’t be that difficult to design a way to get the wings off faster…that’s not something I see myself working on right now, but if you (or anyone else out there) can come up with a fix, I’ll post it here on my blog.
Bob