Cascade Crew

aaron_sK · Posted: Thu Apr 04, 2013 8:20 am Post subject:

Mmm... Hemlock... Very Happy

I understand why Hem gets used over Doug fir or whatever, it always comes down to price. In your application the added weight of the fir would be a consideration as well.

A lot of the hemlock that is grown is destined for, shall we say "entry level" uses like cheap trim (that needs to not be MDF) and interior wall studs for cheap tract housing. That means it is grown fast (wide rings, very soft, blows out when you nail it).

Like anything it's all in what the yard has and how good you are at picking it. I know that it is getting very hard to get any kind of decent wood out of lumber yards. Trees have been bred to grow so fast for so long now that they are getting very weak, and the mills are willing to put out some real crappy stuff. You need to be especially careful due to the small dimensions of your build. If you are buying 1x1 material you are at a little over a half square inch on your cross section. If you buy wood that has been grown fast you may only have a couple rings per stick, and a little whoop in the grain or a small knot that wouldn't make a difference in a larger piece of wood, will make your piece unusable.

I wasn't dumping on your engineering or technical ability. I still think this is a crazy idea, but I've had a few of those myself, and I have faith that you will see it through, Jim. As you said, you haven't been exploded yet. Cool

chevymad · Posted: Thu Apr 04, 2013 11:35 am Post subject:

You did see there are rules for minimum rings per inch and ring parallelism didn't you Aaron?

aaron_sK · Posted: Thu Apr 04, 2013 11:44 am Post subject:

Yes, for production planes using FAA-approved lumber.

Jim's project would fall under "experimental" if I have read the page correctly, and I would bet that his lumber came from Bud's in South Bend or one of the yards in Aberdeen.

flea · Posted: Thu Apr 04, 2013 2:54 pm Post subject:

You would be right Aaron, but the criteria is still the same for me for obvious reasons.
The grain is running straight, with between 8 and 10 per inch.

But either way 3.00 per foot plus about a buck a foot shipping makes selective shopping worth while.

aaron_sK · Posted: Thu Apr 04, 2013 4:59 pm Post subject:

jchaussee · Member Joined: 14 Nov 2010 Posts: 1318 Location: renton

Ya lumber is crap now days. What is now number 2 grade used to be what we used as utility. I only get select if hem/fir or i get douglas fir.

Al Hasse · Posted: Mon Apr 08, 2013 3:55 pm Post subject:

My cousin in Michigan has a plane project going also. A 1947 Piper J-3 Cub. From his post on Facebook, he's just finishing up with part of the tail section, "recovering the tail feathers" he says.

flea · Posted: Mon Apr 08, 2013 5:23 pm Post subject:

I'd love a cub, but they really are too expensive. Last I checked on them they were north of 40k for a good low hour plane. Too much for what you get...but still it is a cub.

Al Hasse · Posted: Mon Apr 08, 2013 5:56 pm Post subject:

From the looks of it, he's building from scratch, too. From his Facebook post...

flea · Posted: Mon Apr 08, 2013 6:12 pm Post subject:

Maybe building it from scratch. A cub is just steel tube and fabric. Pretty simple really.
It really blows my mind though, a real cub can be had for 40, or these people will be more than happy to build you a replica for only. . . well more than 40.

http://www.cubcrafters.com/aircraft

A real one.

http://www.trade-a-plane.com/detail/aircraft/Single+Engine+Piston/1946/Piper/J-3+Cub/1529251.html