Friday, May 11, 2012

Everything takes longer...

Everything takes longer than you think. I attacked the formwork first thing this morning with the aim of drilling all the holes I need to mount the panels at each level. Doesn’t sound like this would take very long, just drilling a few holes, right?

Well, at one end this was relatively easy - the holes pass through the 90x45 pine column braces, so yes, these were pretty easy. Measure twice, drill once ;)

The other end however was a bit more of a challenge - this column has the 100x50 “tongue” timber fitted to form a groove in the wall which forms both a control joint and a mechanical connection to the next panel. With the way I’ve set up my forms (in order to minimise the number of through holes in the earth for clamping bolts) the bolts at this end pass precisely through the joint between this and the next panel. This means there needs to be a channel in the formwork in which the bolt will (half) sit.

I should have cut this with the router before I assembled the forms, but I didn’t did I? So instead, I purchased a 14mm auger specifically for this task but I couldn’t find one long enough to cut all the way through. So, I wound up improvising with a 1/4” drive 3/8” socket and extension bar in the drill, which cut just over half way. Meeting the hole from the other side however was more of a challenge than I was capable of most of the time, so the bars will have to be wound (or bashed) through in about half of the cases. With any luck I’ll be able to minimise the amount of tear-out of the earth panel.

Seriously complicating all of the above is the fact that the batteries in my drill don’t last very long. I had the generator running pretty much all day, charging the spare battery (but never all the way before I needed it). I spent more time changing batteries than drilling holes, it seems.

So it was getting dark by the time I had the formwork finished. Just enough time to screen a few metres of soil, which was an adventure in itself as I overbalanced the bobcat with a very full bucket at full height, and gently tipped it over onto its nose and came to rest on top of the soil screener. Emptying the bucket had the machine very gently right itself, the rear wheels coming back to earth with a soft thud. Alissa had arrived with the kids shortly before so I’m sure I gave her a bit of a fright, me hanging by the seatbelt…

Oh yes, the photo’s. Here’s what took me all day…

Here you can see the clamping bolts rebated nicely in the column.

Oh yes. One lesson I learned from the test wall is that the panels will bow outwards with the pressure of ramming, regardless of their strength. To prevent this, I’ve decided to compromise my hell-bent aversion to holes in the wall by installing a clamping bolt half way along the panel’s length at the top (and also the bottom of the first panel). There’ll be a hole to patch, but at least it’ll be in a straight wall ;) I’ve also decided to install two courses of panels bolted together at the beginning, rather than start with only one course. This should add to the strength at the cost of inconvenient access for the first few layers.

So I’m all set for a start at sparrow’s tomorrow. For now, it’s off to the pub for dinner with Alissa and the kids :)

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