Huichol page 33  June 21st - 24th trip 

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I have to admit I was surprised when I returned to find all three trusses up in their brackets on all three sets of piers. They weren't where they needed to be, they weren't tied off on each end as I requested, but they were up on the posts.
Here they are using the block and tackle chainhoist I found at a roadside  fleamarket along with their "tripod" as we engine pullers call it, to adjust the position of the trusses so they are parallel to the ground and have the same amount showing off both ends from the pillars. The biggest problem here was drilling the 1/2" holes through the 6" U channel so the truss could be bolted securely to the U brackets imbedded in the concrete pillars. 
Drilling 1/2" holes in thick steel using a drill press is easy; doing so 8 feet in the air with a hand drill is a whole 'nother story. Thank goodness I had the presence to buy a cheap 6" bench grinder so we could keep sharpening drill bits to get through this phase; it took much of the afternoon just to get the 12 holes drilled
to be able to install the 1/2" threaded rod. 

tripod set up used to raise trusses into position

Setting up chain hoist to move truss into correct position

 Next phase was setting and welding the small 4" pieces of angle iron to the trusses so the 6" U channel that would support the laminar could be secured. 
Preparing angle brackets for welding

closeup of angle bracket

One of the hardest parts for me personally was welding the 1 meter 
piece of 14 gauge 6" U channel in between the two 6 meter pieces so 
we had one long 13 meter piece of 6" U channel to actually secure to the 
trusses to support the laminar. For those of you who do arc welding you 
know how difficult it can be to arc weld  metal less than a 1/16" thick
without burning holes through it.  The Infra Arc Welder at 65 amps did 
amazingly well even though it was very difficult to get an arc started with 
such low amperage. You can see the long piece resulting in the middle 
near the floor in this pic. We had to make 6 of these. All the 4" support 
brackets are now welded on and we are ready to install these long pieces;
which also presented challenges as 13 meters of 14 gauge U channel 
wants to play the twist game in stead of sitting square on the trusses. 
Luckily I brought my collection of metal clamps, wood clamps and ratchet binders which allowed us to make the proper alignments. 

Trusses up and bolted in place

Welding in the cross supports was very time consuming. Besides welding 
the  6" U channel to the 4" angle bracket, an 8" piece of flat bar was also 
used to hold it into position and then a 20" piece of angle stock to  cross 
brace it so there would be no lateral movement of the whole structure.
See second pic below for a closeup of that detail. That's Ber 16 feet in 
the air welding the long 14 gauge laminar support beams. 

Ber welding in cross supports

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