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 on: Yesterday at 06:09:25 PM 
Started by Joseph Patterson - Last post by Ty Marcucci
Thanks for the posting Joseph.  I was all packed , ready to go, motel reservations, then the flood.  We have a solar water heating system. Came with the house. Works like  a charm. Two 120 gallon storage tanks, NEVER without hot water. But then there is only me and Mary and two spoiled cats. They don't use water, just spit, Any way, Wednesday I noticed a lot and I mean a lot of water in the laundry room. It had been raining, but with a new roof, I didn't think it was from rain. After about one minute of exploring I could see water slowly flowing out of the top of one of the tanks.  This system was installed in 1987, do the math. We called a maintenance  guy that fixed one of the silicone pumps about 6 years ago, but he is long  gone. Tried a local solar company, they do electricity only, but they knew a guy in Atlanta. Called him and he got here yesterday, finally, and in four hours he and his crew removed the two old tanks replaced them with one 80 gallon tank. High and dry now. But I missed a contest I had been looking forward to and had (four) no three trimmed planes ready to go. Crashed one due to bell crank failure. *&&^%$. "It's always some thing" Roseana Danna. Hoff

 on: Yesterday at 06:00:15 PM 
Started by frank mccune - Last post by MikeyPratt
    Hi Randy:

    A couple of days ago, I mixed up my next gallon of fuel and I too mixed 14% syn,, 14% castor and 10% nitro.  I am going to try this for all of my fuel needs.  I still keep a bit no nitro fuel available for testing odds and ends.

                                                                                                        Be well,

                                                                                                        Frank McCune

That recipe will work just fine.  Oh! If you don't want to mess with that lousy, old cranky OS 35/40 just send it to me.  I have one that was built by the Tom and it only has about 55 + gallons threw it and still runs like a champ.


 on: Yesterday at 05:54:23 PM 
Started by Chris Wilson - Last post by Howard Rush
I did some ciphering to try to figure this out.  First, some assumptions:
Bellcrank arms are equal length, hence tension on each line due to inertial and aerodynamic forces on the airplane (not counting forces required to react hinge moment) is the same.  
Drag and line-inertia components of line tension are ignored.
Handle mass is ignored.
Bellcrank rotational acceleration is ignored.

The first picture shows the things I used in the calculation.  I allowed for different line spacing for up and down and for different overhang for the up and down lines.  What the heck, why not?  I calculated hup from aup, cup, and δhandle, and hdown from adown, cdown, and δhandle.

The second picture is one way to look at the forces on the handle from the lines and the force and moment applied by the flier.  After seeing what the guys wrote above, I drew the third picture, which may be equivalent.  I separated Tc, the forces needed to react control surface hinge moment, from T, the "common-mode" line tension due to inertial and aerodynamic forces on the airplane.  T includes mV2/r and forces from engine offset, the paltrey fuselage lift, and wing lift * sin of the bank angle.  An interesting aside is that when Tc = T/2, you've hit the Netzeband Wall.

I attached an Excel file you can fiddle with to see the effect of the parameters in the first picture.  The few of you who will want to see the formulas can get them from the Excel cells; they're too hard to type here.   Behold that the distance you have to move the point of average finger force, hfingers in the third picture, is exactly the same number as the net moment from common-mode line tension (M in picture 2) per lb. of line tension.

If you set the c distances to zero, as in Sleepy Gomez's clever handles, the only moment (or finger movement) you will feel is from the airplane's control surface hinge moment.  "Overhang" adds some artificial feel.  Why would you want that, and how much would you want?  My guess is that you want to get some feedback at the handle proportional to how much you are actually deflecting the control surfaces. Because the amount you can deflect the control surfaces (which are on the far end of a 70-foot spring) is a function of the common-mode line tension T, you might want to get some of this feedback from common-mode line tension via overhang.  I don't know offhand how to calculate how much overhang that is, nor how I'd know if I got it right experimentally, nor if my hunch about what overhang is for is correct.  

Edited to fix Excel file.  Tangent, Arctangent, what's the difference?

 on: Yesterday at 05:33:10 PM 
Started by Bootlegger - Last post by Wynn Robins
OMG..... pray - really -  HAHAHAHAHAHAAA

I'll talk to my girlfriends cat for you guys - will get the same results

 on: Yesterday at 05:30:57 PM 
Started by Bootlegger - Last post by Jim Kraft
We could at least pray that the FAA would change their mind on over reaching our model airplane hobby. Divine intervention is about the only way this hobby is going to last more than a few more years otherwise.

 on: Yesterday at 05:21:57 PM 
Started by Bootlegger - Last post by dennis lipsett
Agree'd, there needs to be a no politics no religion on this forum, for crying out loud guy's this a toy airplane site, leave the politics and religion at home, as stated there are other sites for that stuff.

I totally agree.


 on: Yesterday at 05:05:25 PM 
Started by MikeyPratt - Last post by MikeyPratt
Contact, they are on the web and still are selling parts. You have to send
2 bucks for the parts catalog. i am looking at the catalog and they have most of what you want.


Hi Bruce,
Woody had most of the parts I needed.  Can you check your catalog and see if they have a connecting rod and wrist pin, front bearing, and maybe a cylinder.  I think the cylinder is ok but it really needs a con-rod and pin.

Thanks in advance,

 on: Yesterday at 04:30:29 PM 
Started by Paul Smith - Last post by Motorman
Ready to rock in south Jersey.


 on: Yesterday at 03:42:20 PM 
Started by RandySmith - Last post by RandySmith
These were slick heads with no fins, some cut before or after anodizing
Huge difference in performance in the 40 engine with these as opposed to the no fin heads


 on: Yesterday at 03:33:13 PM 
Started by Joseph Patterson - Last post by Jason Greer
Thanks for all that you do as well, Doug!  We really appreciate you and Mrs.Kathleen coming up and taking care of us!


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