rjmack
Platinum Member
actually, for some reason i was thinking you were going to have a 7 foot span.
my gantry is 9 feet inside and i have never had a problem with width. as you can see, that welding deck fits easily. then again, i don't work on big rigs.
regarding the wide flange, what i meant by boxing the end is to put a piece of 1/4 or 3/8 x4 flat bar from the bottom flange to the top flange at the end of the beam. you then weld it all the way around. what this does is take the strength of the flange and basically wrap it around the end of the beam. .
what are shown in those pictures are generally called gussets or beam stiffeners. they are used to reduce flexing at points along the beam, for instance if you had a leg going up or down somewhere along the beam. in this instance i think boxing the end would be better because you use one piece of steel to do the job instead of two and you wouldn't have any weld across the section of the beam. also, nothing to interfere with your trolley.
if you are determined to go with an 11 foot span you would probably need knee braces or some kind of bracing at the top corners. that, in turn, would reduce the overall useable span accordingly. if you are determined to go with a trolley, and 11 foot span, you can still brace the top corners externally, after you box the ends.
also, my gantry is 9 feet tall, i believe the bottom pieces that sit on the ground are about 4 feet long. i would be very hesitant to go any shorter than that for your wheel spacing, probably longer would be better, you will loose some distance because of having to set the wheels back in a bit for mounting too.
my gantry is 9 feet inside and i have never had a problem with width. as you can see, that welding deck fits easily. then again, i don't work on big rigs.
regarding the wide flange, what i meant by boxing the end is to put a piece of 1/4 or 3/8 x4 flat bar from the bottom flange to the top flange at the end of the beam. you then weld it all the way around. what this does is take the strength of the flange and basically wrap it around the end of the beam. .
what are shown in those pictures are generally called gussets or beam stiffeners. they are used to reduce flexing at points along the beam, for instance if you had a leg going up or down somewhere along the beam. in this instance i think boxing the end would be better because you use one piece of steel to do the job instead of two and you wouldn't have any weld across the section of the beam. also, nothing to interfere with your trolley.
if you are determined to go with an 11 foot span you would probably need knee braces or some kind of bracing at the top corners. that, in turn, would reduce the overall useable span accordingly. if you are determined to go with a trolley, and 11 foot span, you can still brace the top corners externally, after you box the ends.
also, my gantry is 9 feet tall, i believe the bottom pieces that sit on the ground are about 4 feet long. i would be very hesitant to go any shorter than that for your wheel spacing, probably longer would be better, you will loose some distance because of having to set the wheels back in a bit for mounting too.
