Me and danny looked at it breifly this evening. There’s still a 1/16" difference in Z between parts of the bed. I don’t think it’s an issue with needing a support in the middle, since we didn’t used to have this problem.
Danny pointed out that the X=0 spoil board isn’t mounted to the rails near X=4. That means that spoilboard is only attached in 2 places, not the 4 it could be attached in. The X=8 spoilboard is missing some hardware at the x=8 end as well, and those bolts aren’t fully inside the spoilboard. There’s also an issue with how the brackets between the extrusions are attached. They should be setup so they are providing clamping force between the two extrusions. Instead, they are holding the extrusions apart, so the load is being transferred on the little L’s instead of the much larger extrusions. I see what he’s talking about, and I agree with the assessment.
I don’t know what it’d take for me to be able to go make those adjustments like who is in charge of that machine?
I had the same conversation with Danny. We are planning on fixing those issue when we rotate the whole machine. We’d love some extra help when that time comes.
I’ve been giving it some thought. The new spoilboard is significantly offset from where it should be and needs new holes drilled as part of this to place it at the correct location. These really should be low-profile countersunk bolts too, or at least wafers. Part of the difficulty is hidden T-nuts can get lost in the rail- if loosened and they fall and move even 1/2" down the rail, there’s no easy way to slide them back and retrieve them because the bed covers the slot.
The better solution I can think of is to instead use a 5 ft long aluminum flat that runs inside the length of the crossmember’s T-slot, long enough to protrude past the bed on one side. The sides of those crossmembers is open, so we can slide things in and out freely at any time. The bar would be drilled and tapped at specific intervals to accept the bolts. That’s how the V-rail is mounted already, one looooong aluminum flat bar drilled and tapped for all the connecting bolts. That puts the holes at known intervals and there is no way the T-nuts can get “lost” as long as any one bolt in the row remains, and if they’re all removed, then the whole bar can easily be retrieved and realigned with the holes so the bolts can go back in.
So, next step would be to look up what flat size that is and get a bunch from Metals4U and drill/tap it. Needs to be metric bolts now. I have thread forming roll taps for this, they’re super easy to make high quality threads.
Would be REALLY good idea for a locking feature so the bolts won’t back out under vibration. But the underside isn’t accessible for adding traditional locknuts or lockwashers. One thing that comes to mind is captive body panel “speed clips” on the bar instead of threaded holes, like used on car fairings and panels. Those come in up to M8 at least, and the common type just has a bulge and hole stamped in it that should be self-locking. Or, well, the plan “A” of a bar with threaded holes is already incapable of turning underneath, so just using wafer bolts with a lockwasher means it cannot turn in the MDF so it can’t loosen up. I like this plan.
We can just try to fix the install that’s there with lesser effort, for now, by sliding the crossmember underneath the seam so both sheets will be bolted down to the slots underneath, and make a number of new holes. I think it’s best to get the specifics of what hole size and placement it will ultimately use so the holes will be compatible.
