[CadRhino]

I am looking at machining a pocket at the end of a 3/8" 1 1/2" x 96" 6061 aluminum bar and was curious if anyone has clamped up such a long part to do detail work on.
If I attempt this, I will most likely hold the end to be pocketed in a vice and hang the other end off and clamp it to a piece of plywood that rests on an adjustable roller table.
Anyone worked on such a long piece before (with success that is)? If so, what would you suggest.
Thanks for any input.
Best,
CR

[pickled]

Been there. I had several wide 10 foot sections of material that needed to be precisely slotted at both ends. I bolted a sheet of 1" thick UHMW to the table, set the material on the UHMW, placed a 2x4 (already had milled a shallow channel for the material) over top and used long deck screws to secure it to the UHMW once it was parallel. The rest of the span was supported by 2 roller stands. I had to take half of my stand apart before this because towards the end of the slotting operations there was interference between the material and the side wall of the stand as I approached the maximum Y extent. Just verify your travel envelope before you start. Also the unsupported section between your vice and first contact point will tend to chatter like hell as it flexes with motion! That's why I chose to put everything flat to the UHMW.

[Moggot]

This sounds like a reasonable plan. As has already been suggested, check your travel extents very carefully. Even if you're comfortably within the axis limits the beam may translate right into something important and the X/Y axis can produce a tremendous amount of force.

When faced with a somewhat similar situation I opted to cut the section to be milled off, and welded it back onto the beam post machining.

[CadRhino]

Thanks for both of your input. I will give it a try. Would love to do a small part to weld back on but my welding skills are for strength only and look horrible.
Thanks
CR

[pickled]

I feel your pain there CR. Before I became a proficient welder in the late 90's people would ask me if I could give them a "stack of dimes" look on their parts when a weldment was specified. I always told them "Yes, I can do that, but you might have to take a die grinder to it afterwards to dig through the pile of loose change that I'm going to leave for you first". Many times "Pretty" doesn't mean that the welds will pass X-ray or a bend test anyhow. Good luck setting up your part I think that you are going to be fine.