Formwork, Part Two

A few months ago a commenter asked about how to make formwork that won't blow out at the bottom. Here is how we're doing it (and at the same time ensuring a wall of even thickness):

6 inch form tie

That's a 6-inch form tie, made by Simpson. There are other brands and basic appearances, but this is the general idea. To tie the form together you stick this through a small slot you've cut in the formwork.

Cutting little holes for the form ties

So this afternoon that's what we did: cut little matching slots in the formwork.

Cutting formwork with a Dremel tool

First I drilled a couple of holes through the matched-up forms to make each side of the slot, then we could use the Dremel tool to cut the slot itself through a single layer. (It just wasn't long enough to do both layers at once.)

Form ties in place

We fitted all the forms we had ready in place, with form ties. This helped us get a better idea of how we need to build out those forms as we progress. You can see that the little tabs on the tie hold the wall forms the measured distance apart. This works best when the holes are lined up with each other.

The wedge holds the form in place

The wedge pieces slide in the holes on the sides and wedge the formwork into place. It makes a nice, tight connection. You can see in this photo that the "sleds" we made yesterday are the front of the wall formwork, with a 2x4 along each edge for reinforcement. That helps with the pressure of the concrete on the wall, as well.

Today we got several sections of the formwork put together and set in place, but we still have all the columns and a few of the odder spots to work with. We had a minor setback because Noel managed to pull a muscle in his back and will be laid up at least for a couple days with ice packs and ibuprofen. Welcome to old age!

posted by ayse on 04/17/11


D'oh! on Noel pulling a muscle. I'm in the middle of the Habitat EB build-a-thon, but so far the worst problem was my wedding ring pinching against my palm and making a bloody mess. Looked much worse than it is, but the EMT gave me a cool gymnastics-style bandage :-)

As always, give a shout if you want an extra pair of hands.

Oh, I've done that with my ring. Not to the point of needing bandaging, but it hurt like mad. I try to remember to take the ring off when I am going to be doing a bunch of work with my hands. I think we're good on labour availability right now, but thanks for the offer!

This is why I try to stay away from major home renovations. Ouch! Hope he's feeling better and you're able to move along with the projects you have for the house!

He's feeling much better, enough so that we can continue work this weekend. Yay for ice and ibuprofen.

Note: We're getting pummeled with spam comments, so I've turned off the ability to use any HTML or include any links for the time being. Email with any issues.

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