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General control line discussion => Open Forum => Topic started by: Jim Roselle on January 07, 2014, 06:45:22 AM

Title: Akromaster bellcrank
Post by: Jim Roselle on January 07, 2014, 06:45:22 AM
Hi all,

I am currently building a sig akromaster. The supplied bellcrank is the same one that comes with 1/2a kits, I plan on swapping it for an aluminum fox bellcrank. Will the steel leadouts be ok or should I sleeve them where they go through the bellcrank.

Thank you,
Jim
Title: Re: Akromaster bellcrank
Post by: DanielGelinas on January 07, 2014, 08:25:28 AM
Hi Jim,

I changed mine to a 2 inch nylon bellcrank from Brodak. Worked well for me.
I wouldn't go the metal to metal way as it will quickly wear out...
Good luck with your build.
I put an os LA.10 in mine and it flies fine...

-Dan
Title: Re: Akromaster bellcrank
Post by: Duke.Johnson on January 07, 2014, 08:39:56 AM
I think I put a 3" bellcrank in mine last time. I have a kit ready to build now and thought I'd use a 3" bellcrank again.  Does that not sound right?  I want to copy the kit and build two more and make them E-Akromasters.  I'd like them to really fly well, so I'll be watching this thread.

Maybe it was a 2 1/2".
Title: Re: Akromaster bellcrank
Post by: Russell Shaffer on January 07, 2014, 08:58:59 AM
I put a 3 inch bellcrank in my first Akromaster, it took a little fiddling  to get clearance.  I have built 2 more and just used the supplied kit bellcrank because the airplane is very light and they have held up fine.  You do have to move your lines quite close together on the handle. 
Title: Re: Akromaster bellcrank
Post by: Tim Wescott on January 07, 2014, 09:14:39 AM
I'd certainly try to cram a bigger bellcrank in there -- 2 1/2" if I couldn't fit 3.

Jim, as to sleeving the bellcrank -- how many flights before you crash the plane?  If you expect the plane to wear out rather than crash, then putting brass sleeves on the lines ala Allen Brickhaus should make the assembly last better.
Title: Re: Akromaster bellcrank
Post by: john e. holliday on January 07, 2014, 09:59:22 AM
The metal bell cranks will out live most planes if you bush the lead out holes for the cable  to  go through.   I even bush the nylon bell cranks.  I think my Daughters Akromaster was built box stock.  All I did was spray the epoxy paint for her.   
Title: Re: Akromaster bellcrank
Post by: Dan McEntee on January 07, 2014, 11:21:45 AM
  By All means use a bigger bell crank, and bush the lead outs. Typically, if you use a metal bell crank, and use cable type lead outs, always bush them. The metal tends to saw it's way through the cable. On plastic bell cranks, I have seen cable lead outs saw through the bell cranks, and pretty quickly, so I always bush plastic bell cranks also. If using solid lead outs, no real need to do it on either.
  Good luck and have fun,
   Dan McEntee
Title: Re: Akromaster bellcrank
Post by: Jim Roselle on January 07, 2014, 10:10:07 PM
Well I decided in the interest of time and probably against my better judgement to go with the supplied bellcrank. Thank you for your input, I hope you don't feel that I wasted your time.
(http://i.imgur.com/7lSwQ8u.jpg)
Title: Re: Akromaster bellcrank
Post by: Tim Wescott on January 07, 2014, 11:12:47 PM
Well I decided in the interest of time and probably against my better judgement to go with the supplied bellcrank. Thank you for your input, I hope you don't feel that I wasted your time.

I can't speak for anyone else, but no, I don't feel you've wasted my time just because you didn't do exactly as I recommended.  It's your plane, after all.

And it's pretty nifty looking, too -- is it an Agromaster, then?
Title: Re: Akromaster bellcrank
Post by: Jim Roselle on January 07, 2014, 11:32:18 PM
I can't speak for anyone else, but no, I don't feel you've wasted my time just because you didn't do exactly as I recommended.  It's your plane, after all.

And it's pretty nifty looking, too -- is it an Agromaster, then?

Agromaster- I like that!

Jim
Title: Re: Akromaster bellcrank
Post by: Akihiro Danjo on January 08, 2014, 12:08:45 AM
Very nice 'Planes'!
Will she be painted white and orange?

Good flying, Aki
Title: Re: Akromaster bellcrank
Post by: Jim Roselle on January 08, 2014, 12:14:37 AM
Very nice 'Planes'!
Will she be painted white and orange?

Good flying, Aki
I will try to replicate this without the razorbacks logo, wing covering will be transparent red.
(http://i.imgur.com/MrPLtGG.jpg)

Jim
Title: Re: Akromaster bellcrank
Post by: Dan McEntee on January 08, 2014, 12:28:04 AM
Well I decided in the interest of time and probably against my better judgement to go with the supplied bellcrank. Thank you for your input, I hope you don't feel that I wasted your time.
(http://i.imgur.com/7lSwQ8u.jpg)

    I think I see "Dusty" in there somewhere!! Neat idea. Wonder what it would take to morph a Twister into Dusty. Hmmmmm?
  What ever you do, keep at it.
  Good luck and have fun,
    Dan McEntee
Title: Re: Akromaster bellcrank
Post by: john e. holliday on January 08, 2014, 08:25:26 AM
Hey, I like your idea of thinking outside the box.   Will  look different among all the cookie cutter stunt jobs. H^^
Title: Re: Akromaster bellcrank
Post by: Russell Shaffer on January 08, 2014, 09:04:19 AM
What engine are you using?  It's looking good.
Title: Re: Akromaster bellcrank
Post by: Jim Roselle on January 08, 2014, 09:17:45 AM
Hey, I like your idea of thinking outside the box.   Will  look different among all the cookie cutter stunt jobs. H^^
Thanks, I've started to like making my models look a little more scale and a little less " model airplaney".

Jim
Title: Re: Akromaster bellcrank
Post by: Jim Roselle on January 08, 2014, 09:19:19 AM
What engine are you using?  It's looking good.
Thank you, I will be using a Fox .15. I know it's not the most popular engine on the forum but it's what I gave.

Jim
Title: Re: Akromaster bellcrank
Post by: Dan McEntee on January 08, 2014, 10:15:00 AM
  I've flown Akromasters with Fox .15s before, just don't over prop it. Even with the wood you are adding, it will be relatively light. This airplane isn't much larger than a lot of 1/2A stunt models, so plan accordingly. A Fox .15 with a 8-4 prop to start with, and maybe a 9-4 if necessary. I think the last one my kid flew we had a 9-4 prop on it. Make sure there is plenty of castor in the fuel, also.
   Good luck and have fun,
  Dan McEntee
Title: Re: Akromaster bellcrank
Post by: George on January 09, 2014, 11:50:51 AM
Some thoughts for the next Akromaster:

Use a 3" bellcrank and either bush or radius the leadout holes. Plan B...use solid leadouts.

Extend the wings by not cutting the LE or TE. Make new parts like extra ribs, more sheeting, longer TE strips, new BC mount, etc. The extra squares will make up for the effort.

If the Fox .15 is a steel-fin or a slant-plug, don't go larger than an 8"x4" prop or it will pull the engine off the power curve and you will have poor performance.

These are merely suggestions. My stock Akromaster has a slant-plug Fox .15X and my extended wing one has a TT .10.

George
Title: Re: Akromaster bellcrank
Post by: Avaiojet on January 10, 2014, 07:05:25 AM
Thank you, I will be using a Fox .15. I know it's not the most popular engine on the forum but it's what I gave. Jim

Jim,

Interesting build!
 
I actually earned my wings with a Fox .15 on a Jr. Flite Streak. I ran that motor for quite some time!

It's a great choice.

I love those dusters, so does Good Will Hinton. Have you seen his build?

I stole your photo. I collect duster photos.  ;D  So thanks for the photo.

You have an interesting project there, creative.

I'll be watching it progress for sure.

Charles

Title: Re: Akromaster bellcrank
Post by: Jim Roselle on January 11, 2014, 05:49:33 PM
What are everyone's thoughts on rudder offset for this model?

Jim
Title: Re: Akromaster bellcrank
Post by: john e. holliday on January 11, 2014, 06:26:07 PM
Same as other designs,  just enough rudder so it doesn't chase you.   Of course being alert on launch helps a lot. mw~
Title: Re: Akromaster bellcrank
Post by: RknRusty on January 11, 2014, 11:10:38 PM
Jim, I'm building without it now. In fact I am going to remove it from my Copeland Skyray. My Shoestring had very little and it made my wingovers easier to guide than the ray. 2 or3 degrees of thrust offset and it should be very well behaved. Always tight on the lines.

Rusty
Title: Re: Akromaster bellcrank
Post by: Jim Roselle on February 15, 2014, 05:01:33 PM
(http://i.imgur.com/JWTSHmH.jpg)
(http://i.imgur.com/maq3o4a.jpg)
(http://i.imgur.com/DDT4Ep8.jpg)
After a little over a quart of powermaster 10/22 with extra castor she turns 11,300 just breaking into a 2 cycle with a apc 8x5. Seems a little fast to me but this is my first non cox .049 build so I am certainly open to advice.

Jim
Title: Re: Akromaster bellcrank
Post by: Dick Pacini on February 15, 2014, 05:13:04 PM
Great looking airplane.  Is the wing a bit cockeyed?  In the top view, it looks like the wing and fuselage are not square and the trailing edge and the elevator hingeline are not parallel.  At least, it looks that way.  Maybe just the camera angle.
Title: Re: Akromaster bellcrank
Post by: Jim Roselle on February 15, 2014, 05:36:51 PM
Great looking airplane.  Is the wing a bit cockeyed?  In the top view, it looks like the wing and fuselage are not square and the trailing edge and the elevator hingeline are not parallel.  At least, it looks that way.  Maybe just the camera angle.
Thank you, must be camera angle and shadows. Just double checked and all is well!

Jim
Title: Re: Akromaster bellcrank
Post by: Steve Helmick on February 15, 2014, 10:34:54 PM
If it's too fast, I'd suggest an 8-4 APC, as previously mentioned. If that goes too fast, try an 8-3 APC, or longer lines. It should be ok on 50'-52' x .012" 7-strand lines. I used a couple of "steel fin" Fox .15's about, oh, 55 years ago!  H^^ Steve