stunthanger.com
General control line discussion => Open Forum => Topic started by: dave siegler on January 08, 2023, 01:57:28 PM
-
I need a HD 2 lined bellcrank for a 4 engined scale.
I was gifted a Royal B-17 built up for control-line that never flew. It hung from the roof of a hanger for many years.
It never flew and I am going to try to make a sports / demo model out of it.
Its covered with nylon and I think aero-gloss.
if it flys well enough it will be stripped down and recovered.
It's pretty well built, and light enough, but the lead-outs and bellcrank are not up to the task.
I am replacing the bellcrank and lead-outs. 027 leadouts and I need to find a stiffer bellcrank.
It came with no motors but was drilled for a fox of some kind. I am going to use 4 OS 25 RC and put a servo in each nacelle. the tanks look like the never had fuel.
-
Any guess as to all-up weight? I suspect that any commercial 4" bellcrank should do.
If you're worried, you can pull-test the bellcrank separately. If it passes a 10g pull then it should be just fine -- that's twice what you need for scale competition, so is a pretty good guideline for what you'll be doing.
I know a 4" bellcrank made up of 1/8" phenolic pulls well over 50 pounds (I think it was 80). My courage that my bench would stay put failed before I started worrying about the bellcrank.
-
Ok the rc versions weighed about `12 lbs. not sure on this one yes, no motors on it
the bellcrank that was in there was an olf fox one and the leadouts were not bushed.
-
If you are worried, double up the 4 inch bell crank. Might check the push rod also. Dave Trible made the bell crank for my B-25. D>K
-
This one will do the job nicely.
https://sigmfg.com/collections/bellcranks/products/sig-4-bellcranks
-
Check with Brodak. They still may have some Windy PSP heavy duty 4" bellcranks.
-
Brodak's standard 4" bell crank should handle your job! If it weighs any more than that and you're not Hercules, you won't be able to handle it anyway!
Phil Spillman
-
I fly rather large models on a regular basis. The 14 lb B-29 that I fly uses this 4" bellcrank with .027 leadout braided wire with .024 diameter flying lines. I also have a 12 lb sport model that is used as a camera platform. I have a flown a 20 lb model (1/3 scale Spacewalker) and a 17 lb 1/4 scale Morrisey Bravo.
The larger models fly better because the wing loading can be higher than with a smaller model.
https://brodak.com/brodak-6.html
Do yourself a favor and install an adjustable leadout guide. Typically one installs one of these for trimming with aerobatic models but in this case we are going to adjust to keep the line tension within reason.
The larger models pull more. When I fly my smaller models like my 3.5 lb spitfire it pulls but nothing like the B-29.
A special Heavy Duty bellcrank is not required.
Fred
-
When you get it flying bring it to the Aurora ILL CL scale contest on labor day weekend. You can fly it in fun scale, even without scale markings (only lose 5 points).
Is your club going to have a CL scale contest in 2023?
Fred
B-29 flying in formation with a P-38 model
https://www.youtube.com/watch?v=zscd1XMSzbs
-
Is your club going to have a CL scale contest in 2023?
/quote]
yes August 6.
Bob Gialdini Memorial Stunt Scale, Combat.
Mukwonago High School, Mukwonago Wisconsin
August 6, 2023
We just got the site reserved, and are waiting for the sanction to be approved.
-
Awesome to hear about the Aug 6 contest date I will get that into the May 2023 CL Scale column along with the other CL scale contests planned
Thanks,
Fred