It was the morning of May 21 and Mark and I were out at 7 AM. It was going to be hot, so we wanted to start early! With us were Mark’s friend Jeff Goldenson and his 8-year old daughter, Joya; Auyon Mukharji from the band Darlingside, with us for two weeks on workaway; Ari Okun; Kelly Vaillancourt and Dan Taylor from Templeton MA; Chris Monahan all the way from Rochester NY (go Chris!); Willie Crosby, Moo Butler and Emma Golden, all from Montague. Ezra Ward, from Woodsmith Forestry just down the road (also a workshop attendee) had agreed to lead the day. A fun group!
We did not find much online about the practicalities of raising a timber frame with a group of people. Yes, YouTube has some videos, mostly in fast motion, of people raising frames by themselves or with a group. We found these of mediocre use: the motion was too fast to follow, and key moments tended to be missing – like how do you get the extremely heavy plates (long posts that go lengthwise along the building) up on the bents (arches that go cross-wise); or how do you keep a bent from falling over once you have raised it but not secured the braces yet? So, we were happy to have Ezra with us! I am going to try to fill in some of those practical gaps in this letter.
The day before the raising, Mark had built a gin-pole. A gin-pole is the oldest form of crane, invented by the Greeks in the 6th century BC. It is basically a long post – ours was 14’ – that stands on a T-shaped footing and leans ever so slightly forward with a pulley at the top. It is held at the desired angle by two strong ropes anchored firmly in the ground behind the post (Mark used two rebar posts per rope). There are also two ropes angled forward and anchored slightly less firmly. At the top of the gin-pole is a pulley. Ours had a 1:4 ratio, which worked out OK for this small frame. The purposes of the gin pole were to help lift any heavy (or even not so heavy) beams and posts; to help erect the bents; and to hold the bents upright while braces out of 2x4 braces were attached (two braces, one going forward one backward, for each bent post).
And now, the story of how we erected our timber frame!
The first things to go up are the bents. Each bent is an arch that consists of three main pieces: the vertical posts that sit on the ground, and a horizontal crossbeam that keeps the posts from falling inward or outward. Each bent also has two angled braces that connect the posts to the crossbeams. These pieces are assembled on the ground. Pegs to hold the braces and wedges to hold the dove-tail tenons that connect post to crossbeam also go in. In our case, we also had a girt at about 3’ height. The pieces are nudged together with a huge Thor-like hammer made from wood, alternatively called a Persuader, the Commander, or the Beetle. All the bents are assembled before lifting them into place.
You can (and maybe should) assemble the bent right at the position from whence it will be lifted upright, but in case you can’t or forget to, you have to move the bent - which is now too heavy for one or two people to move -- to the position from where it will be lifted up. In our case, about 8 of us took straps, and threaded them under the posts and the crossbeams. Then Ezra called out “Anybody not ready? OK, one, two, three, lift” and we all lifted the bent together and placed the ends of the posts right at the edge of the little concrete piers that they were going to sit on.
Safety tip on carrying with straps: it is tempting to wrap the straps around your hand or wrist as it makes carrying easier. However, as Ezra told us, if you do this, you are attached to the strap, and if whatever heavy thing you are carrying starts to tumble, you will not be able to let go of the strap, and you will tumble with the heavy thing, possibly injuring yourself. So always carry the straps in a manner that you can immediately let them go and toss them away if need be
To lift the bent to the upright position, we first attached a strap from the gin pully to the center of the cross beam. One person was positioned at the gin pole to pull the bent. Two people were each at the ends of the posts, with their feet against the ends to make sure the posts would not slip as the bent was lifted. The rest was positioned around the posts, and at the crossbeam. Again, Ezra called out: “Anybody not ready? OK, one, two, three lift!” and the whole team lifted that heavy bent right up into a vertical position. Once it’s vertical, it’s somewhat stable and two people can stand at each post and hold it in place. We also had the crossbeam still strapped and held up by the gin pole. While the bent was held in place, a couple of people put up the braces – 8- or 10-foot 2x4’s affixed about 4’ up the post and diagonally to the ground, where they can be held in place by a wooden stake.
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