Should I box in the bottom 4 C-channels on my DR4B? Im currently looking to lift around 7 cubes with tray and something that holds the cubes.
So depending on how you mount the joints the bottom joints will not be straight I do not know exactly how teams gets around this issue though. Now as far as weight goes generally speaking, I think the normal single set of C-channels will be enough to lift it without bending/breaking. Especially if you have shorter lifting arms
is this with aluminum or steel?
Aluminum should be strong enough for most applications, only exception I remember is tall skyrise scissor lifts that often had to switch out lower bars with steel.
If by boxing you mean sandwiching the bars of the bottom linkage, then it is dependent on how much space you have. If you can afford the space, there isn’t much reason not to, as long as you brace both bars of the tower. Another thing you can do to increase it’s stability is to put teflon washers between the heads of the screws and the metal, as well as the nylocks on the other side, and flip the keps nuts around to lock the screws to the rotating bars so that the screws have less room to wobble. If you decide you don’t have enough space and need to cantilever the bottom linkage, make sure the screws are still locked to the rotating bars, and if you can turn the bar of the tower sideways and put bearings on the outside, 2 inch screws should be just long enough to go all the way through, and you won’t have much slop problems.