Yellow Pine

[Pearson]

Where do you guys that are doing the Harer STC get your yellow pine to make the D windows with? Living in the Pacific Northwest all they grow up here is Spruce, Fir & Western Red Cedar. I have called literally every place in Portland and no one stocks yellow pine. One place could get it, but had a $500 minimum order.

I even tried to contact the Taylorcraft factory about buying some of those aluminum window frames. No one has responded to my email. Are they still open?

[Carl Ellis]

Re: Yellow Pine

Mark -

Have you tried Woodcrafters?

[VictorBravo]

Re: Yellow Pine

Where do you guys that are doing the Harer STC get your yellow pine to make the D windows with?

You must be kidding... Yellow Pine is freely available at very reasonable prices in the Aircraft Parts aisle #44 at your local orange colored home improvement store. It is right next to the "White Pine", usually in the same bin. You can identify it because it looks a little more yellow than white.

Don't use "treated" wood, it has a lot of copper in it that will corrode the steel fasteners much faster.

Choose a piece with no knots, relatively tight grain, and with only a few mill stamps on the wood with words like "china" or "flooring" or "do it yourself" .

There are almost no loads on this piece, and Yellow Pine was most assuredly chosen solely for it's low cost by Taylorcraft. If there were any kind of loads on it, they would have used Spruce or Birch Aircraft Plywood.

In fact, you can make a thinner, stronger, lighter, and all-around better wood frame from 1/8" Birch Aircraft Plywood than Yellow Pine. And a thinner, stronger and lighter one than plywood from .032 aluminum for that matter.

The FAA has just put out an Advisory Circular or something regarding the substitution of materials and hardware on older aircraft. This is the finest possible example of a "poster child" for substituting plywood or aluminum under this new AC that is imaginable.

[Hank Jarrett]

Re: Yellow Pine

Man, I never thought I would see the day someone would say they can't find any Yellow Pine and all they have here is Spruce! Yellow Pine is what 2x4s are made from around here. Most of it is pure C**P I wouldn't use to chock the wheels of my plane. Talk to your friendly FAA rep (IA who will sign off your plane should do) and see if he will sign off on using some nice Spruce (good grain and ring count) to make a secondary structure window frame instead of Yellow Pine. He is the one who will make the actual decission anyway. Don't be surprised if he looks at you like you just asked him if you could substitute a gold bar for a mud brick.
I WOULDN'T use any Red Cedar! I like the way it works, but when it fails it tends to shatter into a bunch of toad stickers. I wouldn't like a Red Cedar frame just behind my neck, even if the loads that snapped it had probably just turned me into a slimmy bucket of goo.
Hank
If your IA doesn't know much about wood, check the properties of wood at one of the Forrestry Products web sites. Problem with the numbers on most sites is a piece of Pine with really tight growth rings and straight grain will be stronger than a junk piece of Spruce (and the opposite is also true, it's more about the quality of the piece than the species). Spruce and Yellow Pine are very close, but the quality we see on the East coast almost always leads us to use Spruce.

[Carl Ellis]

Re: Yellow Pine

Looks like "yellow pine" describes a family of woods. Take your pick.

http://www.southernpine.com/whatis.shtml

[Pearson]

Re: Yellow Pine

Hank, Bill, Carl, et al,

I know, I know!!! Yellow Pine is junk wood when you live where it grows. While growing up in Texas they made pallets out of yellow pine. Everything was yellow pine. When I lived in Hampton Roads, VA everything was yellow pine. But you just go the Big orange wood store around Portland, OR or Vancouver, WA and ask for yellow pine. I have actually had people roll their eyes back at me when I asked for it.

I asked my brother, who lives in Crosby, Tx just east of Houston, to go buy some wood and ship it to me. He said he tried everyone on the east side of Houston and no one had YELLOW pine. They all wanted to sell him WHITE pine.


What about those aluminum window frames??? Is there another source for those besides the factory? Is there anyone else out there looking for a set of those? As I understand it, you actually need two for each side. Any suggestions or advise?

Now I know what Carl Ellis does when the roads are to icy to go to work. Enjoy your holiday Carl. :-)

[Carl Ellis]

Re: Yellow Pine

Actually, I am at work today. What kind of crazy is that?

[Dan Michaels]

Re: Yellow Pine

You do not have to use yellow pine the circular has a chart that shows wood and what can replace each type. All you have to do is use something as good or better.

I made a panel for my cougar out of Fiberglass. Just use a sheet of peal ply or plastic, lay out the fiber then flood it with resin. Make it big enough to cover to attach points on the frame. Cut out the window after it is complete. This is a basic explanation. If you need more help just ask.

Dan

[Hank Jarrett]

Re: Yellow Pine

There is only one metal frame on each side. I have a set for the 45 that I could trace (or make a cardboard one for a pattern) so you could bend one up. It does have stiffening depressions pressed in but those could be made with a female form routed into a board (Yellow Pine or Spruce, ;-) actually you might want something with a lot more crush strength if you want more than one). Looks like with a routed depression and a dowel and mallet you could even put the stiffeners in.
Hank

[Pearson]

Re: Yellow Pine

Hank,

I appreciate the offer, but I would like to try to avoid having to obtain a 337 for installing an owner produced part. That is why I tried to contact the factory, to see if I could buy a factory made part. I THINK I could get an IA to allow me to install something like that with just a logbook entry. The Portland FSDO, as well as most others these days, is just a real bugger to deal with as far as getting field approvals. I would like to stick to the STC by finding some yellow pine. If I can't do that, then the factory window frames would be my next choice. It is a sad state when your choice of materials is dictated not by the properties of the material, but by the hassle of the paperwork for said material. I have paperwork (the Harer STC) for using yellow pine. That is why it is my first choice.

Making my own windows from scratch would be my last choice, mainly because of the paperwork hassle. If I do end up doing that, aluminum would be my choice of material.

If I can't buy new aluminum window frames from the factory or anywhere else, I think that would be a legal basis for an owner produced part. But does that also apply to parts that were not originally on that model of airplane? I don't think any BC12Ds came from the factory with aluminum window frames. Or is it one of those cases where you just do it and if anybody asks, "It was made that way"? If I copied the factory frames, is it possible to install them with just a logbook entry?

[astjp2]

Re: Yellow Pine

Your STC give you the approval to install the frame, your IA could add a 337 for substituting spruce for the yellow pine, or you could just stick it in and forget about it. Most IA's would not really care if you substituted spruce for pine because it is nonstrutcural. Tim

[Pearson]

Re: Yellow Pine

Part of the problem with using a different kind of wood is that I have already made the hard parts. I have the large radius curved rear part and the front edge already made. I just ran out of wood. I guess I could just start over with spruce, but I was hoping someone knew of somewhere you could just order a piece of wood to be shipped.

[astjp2]

Re: Yellow Pine

So mix them. It wont hurt anything if your IA will allow it. Tim

[Robert Lees]

Re: Yellow Pine

Most IA's would not really care if you substituted spruce for pine

And how many would actually KNOW? (present company excepted, of course). I've used 4130 in replacement for 1020 steel; British spec ali for 2024T3; Ash for pine (it smells nicer) and even the head honcho at the CAA Engineering department didn't pick up on it. All non-structural applications, of course.

It'ld be like using automotive fittings on the tailbrace wires, wing brace wires; brakes; fuel fittings, and all those other applications for which commercially-available fittings were used in the original design. Heaven forbid.

[Hank Jarrett]

Re: Yellow Pine

I think there is some confusion on Owner Produced Parts. You do NOT need an STC, 337 or much of anything else like that to make and use an owner produced part. There are three ways to qualify once you have shown you can't get it from a PMAed source. You can do the design (and meet the original requirements) you can manufacture the part from an existing design, or you can do the quality assurance for the part. When I make my own parts I try to do more than one (just in case the FAA says I didn't meet one of the requirements correctly). If you can demonstrate you can't get the frame from a normal supplier (PMA) and I give you a tracing of an original part, from which you develop a drawing, then you build the part from a sheet of aluminum, followed by a check to make sure the part meets the drawing, you have done all three. That's what I did on my 41 instrument panel. I did all three of the steps, but you actually only have to do one.
Check out FAR 21.303(b)(2). It isn't as hard as you think. Most of us have most of the tools in our garages that Taylor had in his factory when he started. These are pretty simple planes and if he could make them, we should be able to also.
Hank
By the way, the pre-war planes that had the "D" window were mostly made from wood, the metal frames came after the war. Switching from the original to the alternate could be a problem if your IA is a stickler.