Ron, I’ll join in the growing consensus and will relay a story. About ten years or so back an associate was raising a trimber-frame, inside an existing cathedral ceilinged great room, don’t recall the dimensions, but it was sizable, maybe 24 X 28 The plan was to raise in walls 28 X 9 high then piece on piece the “roof” PWJ’s were chosen as the lifting apparatus, largely because it jived with the unusual interior situation, on the first pick, at that critical angle of incline, one of the Beebee comalongs in one of the jacks failed, it fortunately didn’t free-spool but it was stuck, no going up and no going down, and the job shut down for some days waiting for plan B
Suffice it to say they aren’t up to the task.
Why not stick with the traditional lifting engines, gins and shear legs and such ?
Read Jacks’ new article and do some research beyond that, and find somebody who knows and uses such rigging and help them raise something.
If you really want to invest in some added safety and mechanical advantage that will reduce the manpower needed to handraise (, without doubt handraiseing does sell timberframes ) Consider Grip-hoists, far from cheap, but worth every single penny.
http://www.torqhoist.com/product_list.ph...CFQxkSAodZHdjHQ Here’s a wall being raised with a useful and interesting variant of Gin known as “unstayed”, at a point in the lift, rope is reversed and you actually begin lowering the Gins, thereby shifting the CG and they then pull the pick the final 10% or so to plumb. The green slings and rope-alongs you see are not lifting, but only serving as adjustable snub lines, they are purely secondary safeties.
Here a Grip is used as an adjustable guy, so these shear legs are safely “luffable” allowing this tie to be inserted in under this cribbed up roof system. And as a sidenote this bridge was rolled off the river on oak shoes and rollers, timber track and with a single
Heavy duty Grip pulling.
Traditional time tested rigging is the right tool for the job, a slight upgrade just makes it all the better
