help with setting throws on a new plane its shows set up in degrees i use inches
 

help with setting throws on a new plane its shows set up in degrees i use inches. the tool i use is in inches. any help ?

http://www.rcuniverse.com/forum/atta...mentid=2018420

hope this helps: http://www.1728.org/angsize.htm

Its been some time since I last wanted to actually measure throws as I find I do better just by

going with my own eyeball and please I am no way trying to sound pretentious but you can develop an eye for that sort of thing but of course there is no way you can communicate such in a medium like this.

So here are four devices I have accumulated, one homemade and three commercial. Three all work in the same way and as you found out they also are only calibrated in inchs or Millimeters, forgive me but I don,t speak metric so I always ignore that side of the scale.

The fourth one is a very cleaver devise made by CRC and I think sold by Central hobbies. It actually would be very easy to replicate with half of a plastic degree wheel, cloths pin and some scrap wood for pinch plates and a metal pivot for the degree wheel and a weighted pointer.

Its not necessary to crib the airplane to level position. Cloths pin is mearly clipped to the back of the surface. The control surface is moved to in trail position of the stab, fin or wing and the degree wheel quadrant is rotated to zero at the pointer. The surface is now move to position to be measured indicated at the pointed. A simple and effective tool I have no idea if CRC is still going.

John




http://www.rcuniverse.com/forum/atta...mentid=2018424 http://www.rcuniverse.com/forum/atta...mentid=2018425 http://www.rcuniverse.com/forum/atta...mentid=2018426

or you can go to dollar general and get a protractor for 50 cents and get them close enough to test fly. that is what I did when I had the same issue

That's really neat! Or you can use the principle that one degree of angle gives you a rise of .017 inches for one inch of length.

That's what I did, too.

In those days where I am bored but don't feel like jumping into a build I often make up degree meters from scrap wood I have around the shop. I mnake them in left and right so I can set up both ailerons or elevator halves without getting out of my chair when I'm setting up a plane. Easy to make and cost nothing. I like to know what the throws are and have a basic set up and I like to know they are even on all surfaces. It's just part of the set up for me. I have made the one like John showed but these are just simpler.http://www.rcuniverse.com/forum/atta...mentid=2018971http://www.rcuniverse.com/forum/atta...mentid=2018972

In trigonometry, the sine of an angle equals opposite divided by the hypotenuse side. The sine of 20 degrees is .342. The hypotenuse side is the chord of the aileron; lets assume 1.5". So, we have .342 divided by 1.5 equals .228 inches. I graduated from high school in 1954 and we were still using the slide rule. Calculators are so much easier.

This thread got my curiosity up so I looked up Central hobbies and found low an behold selling an almost identical clip on degree indicator to what they used to sell the one I photographed above but now is got another companys name on it:cool:

They still sell them but did you notice the price. They take no time at all to make. I have never measured the rudder throw on a plane, I set them for as much as I can get but it works great for those that do.

What is the point in setting a single control surface for an exact angle of throw (discounting split elevators, dual ailerons, etc.)? Why not get it close, and then adjust it based on how if flies, instead of how it measures? Kind of like spending 30 minutes trying to measure your foot prior to buying a new pair of shoes.

Kurt

As others have stated using a degree meter is a good way for initial setup of your control surfaces. Something I do after initial setup is to insure that the surfaces are perfectly in alignment with one another by firmly taping two 24" carbon rods to the control surfaces facing aft, now when you move the surfaces in all positions and rates these long stable shafts intensify small differences at the end of the shafts allowing me to fine tune the control surface alignment to one another. IMO this is far more important then the overall control throws especially in 3D rates but also in precision rate. I have been doing this for years and can tell you that it is easy to do and very effective.

Bob

If all you are doing is setting up a two or three channel plane there isn't a lot of point in it at all. If you are setting up a plane with ailerons you want then both at the same center and moving the same distance. For a new pilot it is smart to adjust the elevator, even a single at the recommended throw or there abouts. The OP asked about setting throws so I would guess his plane isn't a two channel. All my planes have twin ailerons and split elevators. I can use my mark one eyeball but I have been doing this for a while, a meter or good ruler is still better. Always nice to start out with everything correct
Bob mentioned 3-D. I set my rates on a normal sport plane at 10 or 12 degrees, 3-D I start at about 28 degrees. 10 or 12 I can eyeball, 28-30, not so much.

But are we sure?

Kurt