> Curley wrote: > Big triangles are more good than small triangles.
Bingo!! To be sure I understand the failure, the long outer wall top has moved left or right in the first photo (1727.jpg)? If so, then steel rod or steel cable at a diagonal but in the same plane as the rood deck is a good solution. That is not overhead lifting, so 2:1 safety is suitable meaning I would not recommend putting more than half the minimum breaking strength load on it. 1/8-inch [approx 3.175 mm] GAC (galvanize aircraft cable), 7x19 is typically rated for 900 kg [2000 lb]. 3/16-inch [approx 4.76 mm], 1900 kg [4200 lb] 1/4-inch [approx 6.35 mm], 3175 kg [7000 lb] 5/16-inch [approx 7.94 mm], 4400 kg [9800 lb] The most effective angle for such a brace is 45 degrees. Anything from 30 to 60 works very well. So for 10x20, opposite corners should work well. The most challenging aspect is how to attach steel to the wood. Probably the best is a machine thread shoulder eye bolt all the way through the wood - so a nut on the outside. I would find - or fabricate a _large_ washer to go under that nut. Maybe a fab shop can make you a 10 cm [4.5 inch] square piece of 6 mm [1/4 inch] plate with a hole in the middle. The plywood decking should have worked too - so I'd check for evidence of the roof deck no longer being well attached to the rafters. _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
