Re: Tailfeather gap seals
The stuff on cars and motor homes is UV resistant graphics vinyl. They add a chemical (usually some type of Titanium compound) to resist UV. You can usually get it in clear or solid colors and it takes special inks to make signs that are usually cut out by an NC cutter. There are a couple of types, one of which actually semi-melts into the paint and NEVER comes off. You would NOT want that one! The glider guys use some of the stuff to seal gaps and hinges on sailplanes, but most of the guys I know just use colored to match vinyl tape (cheaper unless there is a sign shop close who will sell you end runs).
Please remember, some of these tapes will get stiff or split in UV. If the tape gets stiff on your controls, how will it change the controlability of the surface? If the edge of the tape lifts it can cause a condition called vortex shedding that can cause flutter. I know the Cub guys have an STC. Does it apply to Taylorcrafts? That is just a "legal" question. More important, what are the SAFETY implications? If you start using sign or tape vinyl do you REALLY KNOW what the long term stability of the material is? I have seen a fuselage to wing tape split and come off a glider. It was a non-event. I have seen the tape on an elevator split on one side. What would happen with the prop swirl pulses hitting the hinge where one side is split? Wonder what RPM would match the natural frequency of the tail and cause it to start twisting? Want to be the one who finds out?
I am NOT trying to just scare anyone, but we are talking about playing with the control system here and that is DANGEROUS if you don't know what you are doing. I know a lot of guys have been flying for years with taped surfaces. Does ANYONE have paperwork to show that the FAA has said this is OK on a Taylorcraft?
Like I said before, it is on my long term test plan. But I want to do it right, and that means a FULL characterization of the plane in the standard configuration, followed by careful, step by step, re-test with the modifications. There is SO MUCH we really don't know about our old birds. If someone knows of someone who actually tested sealed controls, it will save me a lot of work to advance their work. Le t me know if anyone has any test data!
Hank
The stuff on cars and motor homes is UV resistant graphics vinyl. They add a chemical (usually some type of Titanium compound) to resist UV. You can usually get it in clear or solid colors and it takes special inks to make signs that are usually cut out by an NC cutter. There are a couple of types, one of which actually semi-melts into the paint and NEVER comes off. You would NOT want that one! The glider guys use some of the stuff to seal gaps and hinges on sailplanes, but most of the guys I know just use colored to match vinyl tape (cheaper unless there is a sign shop close who will sell you end runs).
Please remember, some of these tapes will get stiff or split in UV. If the tape gets stiff on your controls, how will it change the controlability of the surface? If the edge of the tape lifts it can cause a condition called vortex shedding that can cause flutter. I know the Cub guys have an STC. Does it apply to Taylorcrafts? That is just a "legal" question. More important, what are the SAFETY implications? If you start using sign or tape vinyl do you REALLY KNOW what the long term stability of the material is? I have seen a fuselage to wing tape split and come off a glider. It was a non-event. I have seen the tape on an elevator split on one side. What would happen with the prop swirl pulses hitting the hinge where one side is split? Wonder what RPM would match the natural frequency of the tail and cause it to start twisting? Want to be the one who finds out?
I am NOT trying to just scare anyone, but we are talking about playing with the control system here and that is DANGEROUS if you don't know what you are doing. I know a lot of guys have been flying for years with taped surfaces. Does ANYONE have paperwork to show that the FAA has said this is OK on a Taylorcraft?
Like I said before, it is on my long term test plan. But I want to do it right, and that means a FULL characterization of the plane in the standard configuration, followed by careful, step by step, re-test with the modifications. There is SO MUCH we really don't know about our old birds. If someone knows of someone who actually tested sealed controls, it will save me a lot of work to advance their work. Le t me know if anyone has any test data!
Hank
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