Vacuum Sled Experiment

I know it was talked about before but I’m going to try a vacuum sled this week and here is a rendering of what I’m going to try.

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vacuum? i would try the opposite, make it blow like a hover craft and elliminate any drag

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Nice rendering! What are your expected results with a vacuum? I love the idea of a hover sled ( same design) if you manage to attach a compressor to it.
Edit1: You created a spark that makes me think now, how I can invert the cooling fan of the router into the sled.
In what format are your files and will you share them?

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maybe you don’t have to invert the cooling fan

what if you use the same principle as an airbrush
it blows air into the spraigun to suck the paint fluid in the nozzle

in chemical labs they use the same principle to pump chemicals out of containers with a stream of tap-water

and so does the dyson bladeless fan and the dyson vaccum cleaner as well

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That puts the dust in the right direction as well :+1:
Edit1: Total nonsense actually. The opposite… I should stop commenting on a Friday night :tumbler_glass:

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You both might right about turning it into a hover craft. I haven’t built my final sled yet and still using the temp sled and had some lifting problems.

I did the design in Alibre and I can export Step, ACIS, SLA or some flat DXF. What would you like?

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not sure if the router can handle the extra load. as in having still enough airflow to keep things cool.

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we might just make a maslow to sandblast walls clean

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In the early days I had visions about an ‘Arduino Follow The Sled Dust-Vacuum’, now this idea came back, as my vacuum has an air outlet to attach a pipe. The router cooling should remain untouched, you are right.

Modified the design to “Hover Craft” with dust collection at the tool. Added brass hose nipple for air supply.

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What happens if you get to the edge of the workpiece or over a pocket that’s off the edge of the sled? If if you don’t lose lift completely z cut depth changes

I suppose the side off the edge will have less restriction and more air flow, the side still on the board will have less air flow and less lift. If I get it built I will post my results.

i think you could do both, if you manage to get a high pressure throught the small holes, but not more then the negative pressure of the dust collection, so the air that blows out of the little holes gets sucked to the middle. And (continuuing with the hovercraft idea) maybe put a skirt on the side to imporve this.

The thing you’re looking for with the air gun is a venturi valve if you wanna google it.

You shouldn’t lift it half a centimeter of the workpiece, i’d be surplised if you lift it half a milimeter. So the lost lost lift on the edge isn’t really a problem i think.

btw, a real hover craft has very little pressure underneath. It can run over an egg without breaking it.

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Any thoughts on a sled mod to retrofit it to work with https://www.suckitdustboot.com? It’s made to work with XCarve and Shapeoko CNC, but anything close to this level of dust containment for the Maslow would be amazing.

there’s not as much need with the maslow as we have the large sled that contains
the chips and helps the vaccum pull them up

you could make something to go into the center opening of thesled that would
hold something like the suckitdustboot, but it doesn’t look like they sell
anything that would ‘just work’ for our design.

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Glad I found this. I await my kit arriving and have been thinking a lot about various design ideas. I considered the hover sled idea and various ways I could make it work. Although only in my head i was thinking a similar design to this and so I am keen to know the results of anything you have tried. One thing I was thinking and maybe its a stupid idea was the possibility of attaching a small fan or impeller blades to the router shaft itself to essentially blow air down and through holes in a modified sled or through the usual hole with a skirt around the edge to create a small air cushion. Is this idea of letting the router create its own lift stupid? I realise it would take some work with spindle speed and blade size and number but might work. Would also obviously make the router work harder and probably slow rotation but maybe with small blades to not be too harsh on the router but also create just enough airflow. Your thoughts would be appreciated. I also considered mounting one of the cheap ebay mini blowers on the sled. Something like this

It seems small enough to be possible to mount on the sled and can run from the same 240v supply as the router.

how do you maintain the height of the sled as the bit is cutting into the wood
(especially with a spiral bit that will pull up or down)

I wasnt thinking it would create much of an air cushion. So less than 1mm of lift. Its just a theory but i was thinking that if the under side of the sled had channels running from the center out but not all the way to the edge (like bike spokes) i agree that as the router bit in on Z axis it would pull down but surely if the motion is just on x and y it isnt going to pull down massively or at least it will be a uniform pull if the speed is consistent. I think the key point would be having the fan correct so that it was just enough to reduce friction but not cause more lift that needed. If the router bit pulled then surely the trapped air will be under higher pressure and so would push back. Its just a theory with my school physics head on but its not something i have seen discussed so thought i would throw it out there to either get shot down or for others who are smarter than me to mull over.

what about when you cross over a cut you’ve already made in the workpiece?

how are you going to keep the height the same as you have the motor moving in
the Z direction (drilling into the work)

I would also worry about fan blade balance at 10K RPM.