Does the arm with the vacuum hose actually move back and forth on the rail or is it blocked by the zip-ties? I am designing an arm for my suction and am not sure whether it needs to move back and forth or if it can be static as long as itās got a joint at the wall.
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It moves, but itās so high up and thereās enough āslackā in the hose, that it doesnāt really need to unless I do something where the material is long. So if the end of the material goes past the mid point of the table, you can see the arm swing and retract as the gantry moves along X
If itās high enough to provide slack in the hose, and reaches at least to the middle of the table in X, I donāt think it needs to be articulated. I only did the drawer slide instead of make a hinge because I had it laying around
V2 will be a bent piece of 1ā conduit with a couple of trollies holding the hose, or maybe a total redesign with a hinge. Torsion box idea, with the hoses actually inside it like this
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Dude, I made that armā¦ 
The plans are available in the forum as well as a 4-part documentary on Youtube. Boom Arm Final
For the one over the Lowrider I wanted to go easier, also a torsion box with a removable top so I can put the cables in, a pipe on the top (or better bottom, but it comes from the top) and then I wasnāt sure about whether it should be able to slide or not. At the moment I have got nothing sliding, the hose is just there and does itās job without blocking anything.
This is the plan as of now. Top and bottom have rods as usual that hold the top down, the only part not glued.
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Sweet! Glad to see someone tried it. The drama towards the end of that thread is crazy, but it looks good
Did you do the heated part, or no? Iām not clear exactly on its function or if it is totally necessary if I just use stop pins instead
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Just checked your thread on it and donāt understand how I missed it befor now. Looks great, definitely what I had in mind
Iāll hit you up for stls, or models later if you donāt mind
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The files are hidden here: Boom Arm Final - #18 by Tokoloshe
I only do DXFs, sorry. I work with AutoCAD and therefore never have stls. 
What heated part?
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Yeahā¦ 
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I learned autocad in high school and I really enjoyed it. When i started cnc, I was looking for a similar experience. Librecad is very close (to what I remember) and I used it quite a bit.
Iāve since learned onshape. The sketching is a totally different mind set. But the big advantage is that you can combine the pieces together and make sure they assemble well. The parametric aspect can also save a lot of time.
Iām not trying to convince you, just share my journey. I see the value in the autocad style of cad. It is nice to just draw a line that always starts here and is 100mm long.
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Heated was supposed to say geared. Fat fingers.
But I see from your build that you did.
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How long is each arm section? I canāt get to computer to check sizes on the dxf right now
Thanks dude, appreciate you sharing this. Nice project
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AutoCAD can also do parametric.
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The gears make sure both arms always move, so the arm can never go away from the wall straight and then have a 45% bend. Keeps the arm from flailing around wildly. It took me a while to understand as well why it was there.
Each arm is 1000mm, I cut it by flipping it over, cutting one half, then the other. Going to do the same with the strut plates.
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Why is that important? Not sure I understand why thatās an issue. In fact, for one of my use cases, Iād kinda like it to come out like an L since if it was a > it might conflict with my dangling air and electrical drop
1000mm is 39.37 is freedom units. Thatāll work
I did shitty explaining. It can be an L, but it canāt flail around wildly. Watch this video from the spot I jumped to and you will see the movement: Boom Arm (Schwenkarm) Part IV - Final assembly - YouTube I am too incompetent to explain it, could not even do it in German when I was trying to explain it to my dad when I build itā¦
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Good video. Thanks so much.
The only change is need to make would be to have the hose enter on the side, instead of bottom, because I have this situation coming from my DC
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If you fasten it above the Lowrider, you can easily come from the bottom with your hose (that sounds kinda wrongā¦ :D). If you put it from the side you canāt move the arm the full 180Ā° any more because the hose blocks it at that side. And your hose is huge, I would maybe just hang it under a construction instead of putting it in one? Or are you going to make the diameter smaller?
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Iāll port it down to 2.5ā. I kept the run from the dust collector at 5ā to keep flow and match the rest of my system/
I canāt go from below because it becomes a tripping hazard. But Iāll never need it to be wider than perpendicular to this corner for any reason, so at max rotation, the hose will be 90 at the incoming fitting, if that makes sense
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Here is my extraordinary sketch of what I was thinking:
/edit: Disregard, I am stupid. You want it on the left wallā¦ But works the same
Like that, maybe:
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Thanks Picasso
The only thing wrong with that, is that there is a wall and a window 2 feet to the right, so itāll have weird geometry trying to follow the gantry if itās there. Plus it wonāt reach my assembly table for overhead sanding from that position
If I anchor it right where my 5ā ends , then 76ā reaches 8ā over the edge of my assembly table, and the whole thing can fold and rotate to the right for storage.
Appreciate the help. Looking forward to this project- thanks for doing the heavy lifting.
If I make the whole thing bigger to fit a 4ā hose, and pvc, how heavy do you think itāll end up? Or do you think itāll look too beefy for a small shop? Looking to preserve flow as much as I can
That second pic is perfect, but Iād rather come in from side than do that double 90 coming from the bottom.
4āā would be massive and has some serious weight. If you look at brochures where those arms are sold the holding power for the first segment 1m out is like 750kg, the second segment has got like, 50kg. I am exaggerating, but the force grows exponentially further out. I had a friend who can do statistics calculate it for me and even he kinda failed. He was only sure that I could at least mount 5kg on the arm at the very end. That does work indeed. The first segment would carry me, I am pretty sure about that.
I also could not get it to hold in my wall because it was sandstone, so I drilled completely through, like 30cm and put rods and an aluminium plate on the outside of the houseā¦
\edit: Hereās a pretty good link to how the forces work. It is in German, but google should be able to translate it. And there are pictures that are pretty self explanatory: Biegung berechnen, Biegespannung berechnen
50mm was never a problem for the dust collection. Sure, you do have more flow, but less pressure. When I first connected my 10cm hose of my Makita dust collector (Iike, on of the big ones with the fluffy bag) to my dust collection I was pretty bummed out. When I changed it to my cheapo shop Vac it went a lot better, because it just has a lot more pressure.
Other way round, shop Vac just does not have enough flow for the planer, this is where the big Makita shines.
In conclusion: For the CNC the shop Vac was working better, at least for me (plus: weight).
You are welcome, I had help in the forum as well, same with my Vacuum Table. If I have an idea that seems to cool to be true I first ask the sane people whether it makes senseā¦ I am especially proud of the aluminum segments in the middle. The MPCNC did so well there. 
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