What do you guys think of wood stringers? I bought aluminum stringers from ACS and I don't like them; flimsy and will need to be spliced on the long runs. I've looked around to find some better stringers that I can get shipped in 12' lengths and haven't had much luck. I did find some that would cost ~$100 for the stringers and $250 for the shipping. Supplier said they probly would arrive bent. Haven't found anything locally. After reading guidance from EAA and FAA I bought some lumber and had my grandpa saw some fir stringers. I like them much better than the ACS aluminum stringers but I just want to be sure that they will be strong enough.

Looks to be about as stiff as the alum stringers. I got full length ones for my S Cub, arrived OK. Just don't put your shoulder into 'em turning the tail around.
My 50 yr. old wood ones from Piper were just fine too. (skinnier than yours)

The ones that Mark sold me, despite having some surface corrosion on them (grrrrr) are awesome. They're .050" wall, they bend great in the long axis, and are 16' long.

I was thinking about replacing them with the ones from Spruce because of the corrosion, but maybe I'll just acid etch it off and allodine them. There's a little weight penalty with the thicker wall aluminum, but like Logan says, put your shoulder into it and the lighter stringers may give way.

The wood ones are stiffer than the aluminum. I had them cut thicker and wider in hopes of additional strength.

I tried to get Mark to sell me some but he wouldn't. Too hard to ship I guess. I found the same material that Mark uses and that is the supplier that said they would probly arrive bent. It just wasn't worth it to me to pay more for shipping than I did for the part and still risk them getting bent.

Z, you should use those stringers you got from Mark. I think they look awesome on paper.

Wood, coated with sealer would work fine. But, some Bearhawks have used window screen frame material for stringers with excellent results. This I believed was the material suggested years ago from the mfg. It's available at the local hardware store and cheap..er

I bought ash stringer material from Old Town Canoes...gunwale stock. They were shipped with scarfs, and they joined and milled perfectly with resorcinal glue. They are stiffer than softwoods by a mile if that is what you are after. They went into a PA-20 a long time ago.

I got more last year for a wood canoe restoration. Including shipping, a set of milled gunwales was about 60. Same perfect quality. The folks that sell them will mill them however you want if interested.

I vote for the fir stringers, you're in control of the quality of them. I have used to aluminum screen door material and it worked but I was always worried about a bump and then the fabric sags. Stringer shipping is a pain. I have some 12 ft lengths if the T type wood stringers for my aeronca and found my dad's shipping invoice from 1989 and it was 70 bucks, would be four times that now. Truck dock workers aren't very sensitive to us airplane guys, they think everything should be able to be roughed up.

I went with Univair for both the Bearhawk and Pacer. http://www.univair.com/piper/piper-blan ... ger-blank/
I should add....purchased mine from Stoddart's in Anchorage.... Cost was about 70% less than Univair's list price..

We used fir in #357. Just make sure you leave room for expansion. If you don't the stringers will bend when expanded and start pushing at each end.

This is 2016. Buy aluminum. Wood is for kitchen cabinets. [emoji3]

gbflyer wrote:This is 2016. Buy aluminum. Wood is for kitchen cabinets. [emoji3]

Says the guy that told me to use steam gauge flight instruments[emoji3]

gbflyer wrote:This is 2016. Buy aluminum. Wood is for kitchen cabinets. [emoji3]

x2 !!

Actually, use carbon fiber. That much box section carbon tubing should only run you about $5K.

Think about ease of repair. Wood is MUCH EASIER to fix if you break/bend one. You can glue and fishplate wood. Not sure how you'd successfully fix aluminum stringers, but I'm sure it is more difficult with the fabric still on.

I used both. Wood for the bottom stringers, and aluminum for the top and sides. Wish I would have used all wood. Alan, the other BH builder in Elko at the time, made them for us from fine grained ash obtained locally.

As it turned out, I've had to repair broken bottom stringers and was sure glad they were wood. That was difficult enough. If they had been AL, the repairs would have been very difficult to make and I would have had to cut and repair fabric to accomplish that, and even then, I doubt the repair would have held up as,well as it has.

Hard to beat a good Doug Fir stringer. Give it a good generous coat of Polyfiber's Epoxy Varnish and it'll be good forever!!
John

Thousands of American Champion aircraft have been flying around for many decades with wood stringers. If it works for them......

MTV

whee wrote:

gbflyer wrote:This is 2016. Buy aluminum. Wood is for kitchen cabinets. [emoji3]

Says the guy that told me to use steam gauge flight instruments[emoji3]

Ya got me there! OK, use wood damnit, just put a good waterproof finish on it.

Never made a stringer but Ash is GORGEOUS wood. I like nice tight grain fir, but no contest if you can find some Ash

I used fit because it was available locally and it was one of the two woods that I read was approved, not that I care about the approval. It was hard to find lumber with the proper grain and not knots. I'll see if I can find some ash locally and see if I like it.

I was just going to use polyurethane wood floor finish. I used it on the wood table I built for rafting; I use it as a bench seat and a kitchen counter. Worked great and has protected the wood very well. I'll have a look at Polyfiber's varnish.

Good to see so many suggestions on using wood. I was expecting all the cool kids to veto my wood suggestion. Can't really see the stringers on a Bearhawk but wood looks good with EP420 or similar varnish. You can trust a tree.

Lots of airplanes built of straight grain spruce, not just the stringers.