RTF plane + floats Q
07-31-2006, 08:52 PM
#2
RE: RTF plane + floats Q
There are only 2 documented dumb questions:
(1) Does this make me look fat?
(2) Can I ask you a question?
The answer to YOUR question is: Sure. almost any of 'em.
Despite what people seem to believe, most planes exhibit little more than a small trim change when floats are installed [PROPERLY].
Select the plane depending upon how well you fly. If you're a newbie, floats on your trainer will actually make it MORE aerobatic. If you're experienced, a light 3D model can usually carry floats and do almost anything it could with wheels. It's a little easier to mount the floats on a high-wing plane (trainer, stick) than a low-wing plane (p-51, astro-hog).
Get another landing gear identical to the one that comes on your plane, and install it in the other end of the cabin floor from the original gear. You'll probably have to epoxy in a plywood mounting plate for that. Sorry, but sometimes you just HAVE to use tools.
Select the right floats. Float length should be about 75% of the length of the fuselage. That's about 32" for most 40-size planes, or 40" for most 60-size planes. A really light 3D model can use a size smaller floats(lighter) but it will look funny if the prop is in front of the nose of the floats, and you'll hurt your prop and cut the dock if you taxi up to it with the motor running.
For a .40 size RTF, get the Modelfly floats from Horizon Hobbies. Formarly known as Falcon Floats.
Or, Super Flying Models make some very similar.
Hobby Lobby has ZeeDoo floats that also look like the others but German quality comes at a price.
Plywood kit floats (Great Planes, Sig, Balsa USA) look great and have super water manners but tend to be bigger and heavier than optimal. Besides, you are looking for RTF, right? The plywood kit floats take a lot of building.
The best floats are balsa-covered styrofoam floats, but you have to cover them and do building-stuff to them and you said you wanted a RTF.
Position the float so that the step on the bottom of the float is under a point at about 40% back from the leading edge of the wing.
Rig the floats so that with the top of the float level, the bottom of the (flat-bottom) wing is at least level or maybe just a little bit higher in front. THE FRONT EDGE OF THE WING SHOULD NEVER BE LOWER THAN THE TRAILING EDGE.
If you get a sporty plane with a symmetrical wing, then measure from the wing saddle and use a dry-erase marker on the side of the fuselage for a reference line parallel to the wing. Then install the wing with a little higher leading edge than trailing edge...1/2" works. That'll get you 2.8 degrees on a 10" wide wing, which is plenty.
Your floats should either come with provision for water rudders or they should be included. You probably will need ONE. ALso get a piece of NYROD and attach one end to the rudder horn. Run a loop of it forward to the rear float strut and back to the water rudder. It looks like hell to me, but it works acceptably well and it's quick. Tie it to the aircraft with the little P-shaped clips that they sell for this occasion. 3 are enough. One at each end of the sheath and one to keep the front of the loop from flopping around. Make sure the water rudder goes in the same direction as the air rudder.
Check the plane's balance. It should balance in the same place as it did before the floats. Balance on the spar if you don't have instructions. If it's not balanced, get some of those tape-weights from the auto part store and gently rest them on the top of the floats. Use the smallest amount of weight you can. it goes at the end of the float on the flat deck on top. Trim off little pieces of weight and slide them around until it's perfectly balanced with the smallest amount of weight you can use. While you're at it, suspend the plane from the top of the rudder and the spinner, and make sure it's balanced laterally, too. Ratio your weights between the left float and right float. You'll probably need more on the left float because of the weight of the muffler. When it's balanced front-to-rear AND side-to-side, then pull off the backing tape and stick the weights down.
(1) Does this make me look fat?
(2) Can I ask you a question?
The answer to YOUR question is: Sure. almost any of 'em.
Despite what people seem to believe, most planes exhibit little more than a small trim change when floats are installed [PROPERLY].
Select the plane depending upon how well you fly. If you're a newbie, floats on your trainer will actually make it MORE aerobatic. If you're experienced, a light 3D model can usually carry floats and do almost anything it could with wheels. It's a little easier to mount the floats on a high-wing plane (trainer, stick) than a low-wing plane (p-51, astro-hog).
Get another landing gear identical to the one that comes on your plane, and install it in the other end of the cabin floor from the original gear. You'll probably have to epoxy in a plywood mounting plate for that. Sorry, but sometimes you just HAVE to use tools.
Select the right floats. Float length should be about 75% of the length of the fuselage. That's about 32" for most 40-size planes, or 40" for most 60-size planes. A really light 3D model can use a size smaller floats(lighter) but it will look funny if the prop is in front of the nose of the floats, and you'll hurt your prop and cut the dock if you taxi up to it with the motor running.
For a .40 size RTF, get the Modelfly floats from Horizon Hobbies. Formarly known as Falcon Floats.
Or, Super Flying Models make some very similar.
Hobby Lobby has ZeeDoo floats that also look like the others but German quality comes at a price.
Plywood kit floats (Great Planes, Sig, Balsa USA) look great and have super water manners but tend to be bigger and heavier than optimal. Besides, you are looking for RTF, right? The plywood kit floats take a lot of building.
The best floats are balsa-covered styrofoam floats, but you have to cover them and do building-stuff to them and you said you wanted a RTF.
Position the float so that the step on the bottom of the float is under a point at about 40% back from the leading edge of the wing.
Rig the floats so that with the top of the float level, the bottom of the (flat-bottom) wing is at least level or maybe just a little bit higher in front. THE FRONT EDGE OF THE WING SHOULD NEVER BE LOWER THAN THE TRAILING EDGE.
If you get a sporty plane with a symmetrical wing, then measure from the wing saddle and use a dry-erase marker on the side of the fuselage for a reference line parallel to the wing. Then install the wing with a little higher leading edge than trailing edge...1/2" works. That'll get you 2.8 degrees on a 10" wide wing, which is plenty.
Your floats should either come with provision for water rudders or they should be included. You probably will need ONE. ALso get a piece of NYROD and attach one end to the rudder horn. Run a loop of it forward to the rear float strut and back to the water rudder. It looks like hell to me, but it works acceptably well and it's quick. Tie it to the aircraft with the little P-shaped clips that they sell for this occasion. 3 are enough. One at each end of the sheath and one to keep the front of the loop from flopping around. Make sure the water rudder goes in the same direction as the air rudder.
Check the plane's balance. It should balance in the same place as it did before the floats. Balance on the spar if you don't have instructions. If it's not balanced, get some of those tape-weights from the auto part store and gently rest them on the top of the floats. Use the smallest amount of weight you can. it goes at the end of the float on the flat deck on top. Trim off little pieces of weight and slide them around until it's perfectly balanced with the smallest amount of weight you can use. While you're at it, suspend the plane from the top of the rudder and the spinner, and make sure it's balanced laterally, too. Ratio your weights between the left float and right float. You'll probably need more on the left float because of the weight of the muffler. When it's balanced front-to-rear AND side-to-side, then pull off the backing tape and stick the weights down.
