Wednesday, September 1, 2010

Cabin Building - Day Eleven

We got the first sill beam built-up. Yay!!  Figured we'd do one to start, get a hang of what we're doing, then make the other sill beam and the two matching header beams. I've got pics, but left the camera at the build site... seriously need to put a beeper on that thing!!

Ok, so our beams are built up with three laminations of 2x12 lumber. The center lamination is three 8' boards butted end to end.  Since you don't want the joints in a built-up beam closer than 16 inches, we cut the third board in each of the outer laminations into a 3' section and a 5' section and then alternated them so none of the joints in any laminations are aligned.  1st: 3-8-8-5; 2nd: 8-8-8; 3rd: 5-8-8-3.  After dry fitting them to figure out the cupping and bowing, we ran a bead of construction adhesive between the layers, pre-drilled pilot holes, and spiked them together with two rows of 40d (5") spikes alternating front-back, top-bottom, so there's a nail every 16". 

We made sure that the top edges were straight and flush, but the bottom surfaces are totally haphazard since each board is a slightly different dimension. It's only important that the bottom be flush right where it rests on the plate for the leveling jack, so we'll have to chisel/plane/shave that section out when it comes time to mount them.  But the beam seems pretty solid and should get even less wiggly/bouncy once the adhesive cures and we actually bolt it to the jacks and piers.

We did find a teeny, tiny, itty, bitty little issue when we laid the beam on top of the piers to mark where the jack plates needed to be mortised...   After all our painstaking survey work, we forgot that we needed to inset the outside piers so that the edge was on the X, not the center... so the outer piers were 2.5 inches out which would have put the jack and beam resting on the edge of the pier rather than in center. This could have eventually resulted in catastrophic pier failure since the load on the concrete would have been uneven. The piers needed to be move in so the load would carry in a straight path all the way down the centers.

We had a huge argument about this... I won. This is were we got a small break from the universe because our pads and piers had to be on the surface because of the permafrost... if they'd been dug in, we wouldn't have been able to move them.  So we got out our steel diggy-bar, wedged it under the outer edge of the pad and levered the whole assembly in until it lined up. This took a couple tries. G got increasingly frustrated with the whole thing, and with me especially for insisting that we at least stay within 1" tolerances. During one fine-tuning, he hefted the beam by himself, which was unfortunate since it twisted and went crashing down his shin (the same one he messed up last winter on the evil hidden tree stump). More fighting ensued at this point, but we did move the second pier in as well. Luckily, the inner two piers are bang-on and can stay put :)

I have to give G snaps though, this beam is extremely heavy and there is no way I could even begin to move or lift it on my own without the help of jacks, pulleys and levers.  He just needs to remember to wait a second so I can grab the other end to stabilize it.  At least I'm not a total weakling and can actually lift and move my end to make adjustments, which is no small feat for my tiny 5'6" female self, considering the beam has to weigh at least a quarter ton!

Anyway, we got the piers realigned without further incident or injury, and G hobbled off to rest while I cleaned up. When we got home, I iced his leg, set him up with some Aleve and made dinner in penance ;)

Tomorrow we can *carefuly* move the beam to install the jacks, and then permanently attach it so it'll be safer. Then we can start on the second beam, which should go much faster since we know what we're doing now. Still have to move the other piers, but at least this time it's not a surprise that we end up doing at the end when we're already tired. We may still end up with a little fiddling to get the whole thing square once we put in the edge joists, but at least we'll be as close to square/plumb/level as you can get in the bush with an inexperienced two-person crew and only about half the proper tools and equipment needed ;)

2 comments:

Walkntom said...

Y'all play nice now :-) don't want to have to put you at opposite ends of the playground. Seriously, glad to hear that in spite of bruised shins that things are moving along. Did the brake line get there?

Plickety Cat said...

But D-a-a-a-a-d he keeps touching me and won't stay on his side of the seat!! LOL

No brake lines yet, hopefully they'll be in the mail tommorow.