Protection for the foam wheels

[Matt Piatkowski]

Hello,
I have found that a 3/8" wide band of the electrical tape protects well the foam wheels from wear and tear on the hard surface. The tape becomes rough after 3-4 take-offs and landings and does not allow for the model's side sliding.

Without such tape, I had to replace the foam wheels after 10-15 flights as they were simply getting to small. With tape, after 60 flights on tarmac, the 2.5" foam wheels are still 2.5".

Happy Rolling,
M

[RC Storick]

Hello,
I have found that a 3/8" wide band of the electrical tape protects well the foam wheels from wear and tear on the hard surface. The tape becomes rough after 3-4 take-offs and landings and does not allow for the model's side sliding.

Without such tape, I had to replace the foam wheels after 10-15 flights as they were simply getting to small. With tape, after 60 flights on tarmac, the 2.5" foam wheels are still 2.5".

Happy Rolling,
M

You can coat the foam with ZPoxy and wipe off. Let dry and fly.

[Matt Piatkowski]

Is ZPoxy flexible after setting?
If yes, this is an alternate method.

Also: I saw some fliers in Europe oiling the foam and wiping the excess. This method works but is messy.

[Paul Walker]

[quote
Without such tape, I had to replace the foam wheels after 10-15 flights as they were simply getting to small. With tape, after 60 flights on tarmac, the 2.5" foam wheels are still 2.5".

Happy Rolling,
M
[/quote]

Sounds like your wheels are not alligned correctly.

[Matt Piatkowski]

Hi Paul,
Both planes having the wheels protected by the tape roll well on the hard surface of our circle.
There is no shimmy and take offs and landings are smooth, assuming of course that my input is smooth.

Considering the above, I feel that the wheels are reasonably aligned.
Regards,
M

 

[Paul Walker]

[quote

Considering the above, I feel that the wheels are reasonably aligned.
Regards,
M
[/quote]

Considering the above, I am sure your wheels are misalligned.

[Target]

Paul-
What procedure do you use to assure alignment?
Is there a process that you will use, or is it strictly by eye-balling the wheels?
Thanks.

R,
Target

[Paul Walker]

First, I check the engine offset. Next, the leadout position relative to the CG.

If the engine has offest, then the wheels need to be yawed inward by that amount. With engine offset, the model will yaw out due to the thrust component, and that will cause the wheels to skid if not accounted for. If the leadouts are more than approximately 1 inch behind the CG, calculate that angle, distance aft of the 1 inch location divided by the half span, and take the arctangent of that, and add that angle to the wheel yaw in.  Aft leadouts act similar to engine offset, causing yaw out on takeoff release.This gets it in the ballpark to roll effortlessly without much side force on the wheels.

It could take a little trial and error to get this JUST right.

With engine offset and aft leadouts, it is necessary to point the plane out at takeoff so the wheels will track perfectly at release. If the plane is pointed tangentially, it will move a few feet and then snap the lines tight causing a noticable yaw that the judges can see, and deduct for. Yawed out, the wheels are alligned with the flight path and a smooth takeoff can be had!

The wheels can skid some and the pilot will not know it, but it will scrub off some of the wheel. The softer the wheel material, the more sensitive it is to this.

Of course we are talking about takeoffs from a hard surface here. Grass, no problem here!

[Ken Culbertson]

Let me add to what Paul said.  I go back to the "Old Days" when we used small hard rubber wedge wheels that were very sensitive to alignment.  Our rule of thumb was with the tail wheel straight, get the model to roll along the painted circles which would be an inward arc and to point the plane out enough so that the lines were straight from the handle to the bellcrank.  This prevented the scrubbing and uneven line tension as the plane accelerated.  It also eliminates that annoying yaw you get if one wheel lifts off and you are not perfectly aligned. We also did tricks like uneven landing gear wire or different size wheels to keep the wheels from lifting off separately.  Beats crouching, especially at my age!
 
IMHO, the takeoff and landing are the most overlooked and most important maneuvers in the pattern.  You have a chance to "WOW" the judges before they see that sloppy wing over and it is so easy to learn to do it right.  You should practice perfect takeoff's and landings on every flight, even trim hops. The real kicker is that a plane trimmed to take off perfectly will land the same way - and stay landed!

Ken