they are cheap on ebay.įor a 30' span gantry, with 2 beams, you will need 2 beams on the order of a W12X65. The louden gimbals don t solve this problem.Īsce rail are standard profiles- light rails use hooked bolts to trap the rail over the top flange. so that is 1.5T in the 30' direction and ~1T in the 60' direction. You ALSO have to take into account the HORIZONTAL forces- 20% along the lenght of the gantry and 10% in the direction of gantry travel. so for a hand moved load of 3T you have to size the beams and connections for 1.33*4*3T=of 16T! iirc- for hand moved loads, 1.33*load, 2.0*loads for power trolleys. fatigue and fracture of hangers is non-existant in PROPERLY detailed hangers. Louden gimbal- sure, it looks pretty neat, but if you are getting that much sidesway, then you are going to have other problems. think drinking straw in bending, now brace it in the middle. The c-clamps you guys are refering to reduce the beam's unsupported length. W shapes and HP shaped have PARALLEL flanges
that is why we use trolleys on the bottom flange. Underhung loads on a beam's bottom flange create stabilizing effect- you can hang more load than load from the top. He included the documented weight of the dosser and a picture of the lift in with the proof and RCA / GE said ok how about I bring my lifting beam thingie and we pick up that dosser?. got the answer he liked and then asked if the crane out there would pick it up. He pull in and asks the guy how much that big doser weighs. One day he is driving down the road and he see's a place selling bulldosers cranes and all the other construction machines.
no, HELLOF A LOT OF WEIGHT.It to had to be tested before delivery. I didnt's want to drop them through the bottom of the boat, that would of been a disaster.Īnother friend of mine built a lifting rig for what was then RCA it's now GE and this rig was to lift a lot of weight. I knew what the engines weighed and tested that weight and a little more with barstock. I had to make a sorta gantry lift rig to pull the engines outa my boat.
Nothing wrong with lifting that table like that as proof.