Trim screws.

[astjp2]

These are new old stock too! just ask me...

[Hank Jarrett]

Please let me know what you find out. I will put it in with the drawing files so it will be available again ten years fro now when the next group of guys need them!

[astjp2]

I can probably draw it up, or I can see if the machinist did...Tim

[Bruce Caldwell]

Put me on the list too please
Bruce

[astjp2]

Trim screws came in, these are a package deal, barrel and screw for 175 + shipping. This is an owner produced part, so no paperwork but i can provide the material spec if someone absolutely needs it. PM me your address and I will ship them out USPS priority mail. As an owner produced part, you as the owner/operator will need to do a dimension check with your mechanic to install. Tim

[astjp2]

Oh and if anyone thinks its too expensive, a machine shop charges $105 per hour plus materials so I tried to keep these within reason on price and allow me to make a little something on them. Tim

[Bruce Caldwell]

I'll take one please. Let me know how to pay I can send a check if that works for you.

Bruce Caldwell
15 Fairway Drive
White Salmon WA 98672

[Mike S]

Why are they made from bronze and not regular old CRS? .. I'm just trying to learn.

[Hank Jarrett]

Bronze and brass are both alloys of copper. Bronze was first made around 3500BC (we think) and is better for casting since it is dimensionally more stable and will pick up more detail in casting. It is also MUCH stronger and more resistant to wear than copper.
Brass came in about 500BC and is a specific alloy in the bronze group . It is made from copper and zinc. Brass is more malleable than copper or zinc and melts at 900c. It also flows better when melted.
Bronze is mostly copper but usually has tin added. It may also have phosphorus, manganese, aluminum and silicon. It melts at about 950C is harder, more brittle. Its biggest advantage is its corrosion resistance (especially in and around sea water) and its resistance to galling.
Steel (like cold rolled steel or CRS) rusts badly when exposed to moisture.
If you were wondering where all this was going, you probably have missed a few of my long winded posts. Steel is stronger, but when you get a little rust in those threads the parts are going to jam up and not turn any more. Bronze will be a bit larger part (because it is a bit weaker) and just a bit heavier, but will work for decades, where the steel part will jam up and fail as soon as the protective coating (grease or paint) is gone.
If anyone wants to learn, I am always willing to get long winded. Sometimes I even do it without mistakes. ;-)

Hank

[Hank Jarrett]

The other reason is the FAA probably wouldn't let you substitute materials without jumping through a bunch of hoops. I SERIOUSLY doubt most of them know the actual material properties reasons.

[Mike S]

Thanks for the explanation, Hank, I didn't figure the corrosion angle but that makes perfect sense. What are our trim screws, brass or bronze?

[PA1195]

Piper uses steel in their trim jack screw and yoke. Not suggesting better but they are exposed to weather and some severe loads. They do wear out.

Question: What modern lube for the Taylorcraft trim assembly is recommended for bronze? Yes there's an oil hole but I'm wondering about a pre-anti wear and galling lube during assembly. I like a low temp grease with moly (MoS2) for the Pipers but not sure about the compatibility with these parts. Some use anti-seize lube instead of grease but there's a variety of imbedded materials that may not be compatible. There is a copper anti-seize available: https://www.permatex.com/products/lu...ize-lubricant/

Gary

[astjp2]

These are made from 485 brass. Also known as high-leaded naval brass, 485 brass contains lead for good machinability. It is commonly used for marine hardware, valve stems, and screw machine products. Yield Strength: 25,000 psi. Specifications Met: ASTM B21

Standard 360 brass is only 15,000 psi yield, so the 485 best quality brass for wear long term. Hardness is the same for all of the available brasses in the size used to make these.

[PA1195]

Dr. Tim maybe you can address the pre-lube option?

Gary

[astjp2]

Dr. Tim maybe you can address the pre-lube option?

Gary

Gary, I am not sure what you mean, but I use a heavy oil when I assemble them...the brass is not sintered so it does not self lubricate, that is a sintered bronze thing used in bushings.