Things can change but some things still stay the same

[PatRobinson]

Hi Guys,
I got a TF Score with xmas gift money and the Tom Morris "type" controls I had ordered for it came last week.  This will be the first time I will use this type of control system. This is the "Change" part of this post.

On the elevator horn, I found that the fit of the brass tube bearings on the wire was tight and horn movement on the bearing was stiff.  If the horn wire side-slipped 1/32" or so in the bearing tube the horn would just lock up on the wire or on excess material at the horn/wire junction.
Please note, this is not an attack on the product or on the supplier because I think these horns are superior to earlier products in strength and design. There are limits to the time given to any custom fabricated product that will still allow it to be offered at a reasonable price. Enough said, so please, no flaming vendors.

This is no big deal, and it brings me to the "Stays the Same" part of the post. Since the mid-70's I have used files , sandpaper to smooth all the wire surface and the the wire/horn joint I can get access to and then, I use toothpaste as a lapping compound on the brass tube bearing till I eliminate all bearing binding and stiffness. I have done this with all metal horns 

One trick you guys might find useful in lapping the tube bearing is to put a small rubber coated drum sander mandrel in your drill press.  then take a 1/4" wide rubber band around the rubber mandrel and the other end around the brass tube bearing add toothpase at each end of the tube and start the drill press and spin the bearing. You can move the tube up and down the wire by changing the angle of the wire. Clean off  the excess toothpaste and then clean with some liquid, alcohol or spray cleaner. Start drill press  to rotate tube on rubber band with a little liquid to clean residue from under tube and repeat till all residue is gone.
 
This lapping process results in getting rid of the gritty feel that I have found on most tube bearings and the filing and sanding on the wire gets rid of the binding issues. Together the process gives much smoother horn movement.
The elevator horn for my Score is now "super slick". I may be "hyper finicky" about controls because I lost a plane to stiff controls many years ago and I just started smoothing and lapping everything ever since. To me it is just a  normal part of airplane building.

 Except for the actual lapping process all the rest of this process was easily done while watching tv because it is mostly done by feel. I find producing these "super-slick" horn bearings satisfying work that I expect to complement my new smooth ball link control system. 

Guys, Products may change but the workmanship we all as modelers choose to bring to those products somehow remains the same and I am glad about that fact.
                                                                       Best Wishes ,
                                                                       Pat Robinson

[Mike Lauerman]

Attention to detail has always been the insurance that if something's worth doing, it's worth doing right. I have a scratchbuilt biplane (38" wingspan) that I designed for research on four stroke C/L engines. (back in 1983) The top wing was removable, and adjustable for incidence.
The bellcrank and rear horn had some stiffness, but I was pressed for time, flew it anyway, and nearly crashed it. When I got it back down, I returned home, removed the controls, and polished everything!
  I didn't have time to do it right, but I found time to do it AGAIN! Ironic thing was that it was a 'test plane'. Without everything 'spot-on', how the heck can you test colaterel systems???
A big 'Duh!' for me.

[PatRobinson]

Hi Mike,
I think your message about "taking time to do it right or being forced to take time to redo it" rings very true for many of us. If you hurry your finish the plane may look ugly or at least fall short of your expectations, but if you hurry your install of an airplane's controls you can lose a plane.

Mike thanks for your well stated reply . Well done!

                                                                Pat Robinson

[Leo Mehl]

My take on control systems is that they are the heart of the airplanes longivity and like the wing has to be done right. I have planes that have lasted over ten years and the control systems have outlasted the airplane. Care in constructing the control system is very important. I think I have learned more about control systems in the last decade than I ever knew before. We now have more choices than we did in the 60's for our control systems. It is so much easier than it used to be. All we had in the 50 an60's was metal belcranks that had to be bushed before use along with the control horns. We are really lucky to have these new parts to work with.

[PatRobinson]

Hi Leo,
Years ago I got a very clear object lesson about the cost of rushing the control installation in a stunt plane.  I helped a new flyer learn to fly on my trainer and then to my amazement he scratch built a built up plane in a week.  I checked his controls and found binding and sticking and told him to fix them before flying the plane.  He instead went ahead and flew and crashed the plane. The next week he had a new plane and again it had bad controls and it crashed.  I brought out parts and went through the process to do good controls for him. Two more weeks , two more planes with marginal controls and two more lost airplanes.   Then, he took the time to create good smooth controls and he learned most of the pattern with that plane. When he did crash he cut out those controls and put it in his next plane.

I agree that the modern ball link control systems available today are vastly superior to older controls, but as I found out with the locking up and binding tube horn bearings, you still have to pay attention to the details in order to insure good controls.   Leo, thank you for your input.

                                                                       Pat Robinson