Dust collection without shoe...futile?

Just like the title says.

I have a loc line hooked up to a residential central vac. I have the line pointed at the spindle, but with no shoe I am not getting much collection (especially on MDF, otherwise known as dust SATAN).

I have also not come up with a great way to attach the loc line to the gantry (zip ties require constant fiddling). My problem is that I like to see the tool in the cut when looking for problem with the program, so I have been reluctant to go full shoe. Am I just wasting my time and electricity running this vacuum without a shoe?

I was contemplating attempting to print some fins that would fit over the collet nut on my spindle, so they’d act as a fan blowing the chips to the side of the machine, then, cutting slots along the edges for dust to drop into, and get sucked away from there.

Not sure if it would work as well as a shoe… but it would fix the visibility issue, and should clear dust away from the cutting area.

Workshop dust collectors move a lot of air, they don’t really pull that hard, if that makes sense. So usually, the dust shoe’s job is just to slow the dust down, and the dust collector’s job is to collect it from a large volume, but it only works for basically stopped dust.

I don’t have a residential central vac, but I am wondering if that is the problem. It may be designed to have high pressure and low volume. Are they capable of handling the chips and sawdust? I would consider a shop vac, or a HF dust collector.

You really don’t want it to make a good seal. I have actually had the plate stick to the workpiece and it skipped steps (this is a LR1, with my own DC design).

You really need a shoe if you want to collect a decent amount of dust. The dust is thrown different directions depending on what and how you are cutting so a loc-line wont catch much. I am sure there is a way to design a shoe with plexiglass so you can still see. My CNC is not the MPCNC, but might give you an idea?



The hole in the center lets more air in so that the vac works better.

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Thanks for the the replies everyone.

I spent some time this weekend working on a small z axis independent dust boot. I still need to figure out a skirt. Think this will work if set properly? I worry it is a bit small, but I didn’t want something that would limit my travel. I also have to figure out a different loc line configuration, as this will hit my mid span support.

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You might find this Thingiverse page interesting: https://www.thingiverse.com/thing:4166046. He uses the same bolts you do to mount his vacuum tube, uses a square tube with the same cross-sectional area as his hose, and brings the tube down the backside of his Burly where it has zero impact on the cutting area.

Also I use EVA foam for my skirt on a prototype dust boot for my Primo. You can buy it in thin (2mm?) sheets at most craft stores. I fold it over and snip “bristles” into the foam, offsetting the snips between the two layers. I’ll probably use brush bristles when I finalize my design, but the foam is easy to attach and works well for prototyping.

Thanks! That is actually one of the projects I drew inspiration from. I am trying to adapt the same basic principle but leverage my existing and off the shelf componens (pvc pipe, loc line, etc).

I have a rev 2 dust shoe printing now. Big difference is the inlet section for the loc line is now addressing the shoe tangentially, instead of perpendicularly. This will allow me to make the loc line straighter (avoiding my mid span support) and hoepfully take advantage of air swirl for collection.

image

Well here is what I came up with. I’m gonna use this one as is to see if it even works, but I’m not satisfied with the bristles. I used an old paint brush, but didn’t cut low enough to avoid all of the dried paint, so the bristles are a little stiff.

I also tweaked the design to be ovular, getting the tube connection even further from the spindle for z clearance.

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Marius Hornberger shows his process for creating a dust shoe for his CNC in https://youtu.be/ufXTIu2VmME. The section on the brush starts at about 10:20. He uses shop bench brushes as a source for bristles.

thank you for that link, it is a fantastic and well executed design.

My brush method was actually similar, but my difficulty came from the scale. Mine was soo much smaller it became hard to work with the glue and bristles. Also, my design didnt leave enough room to make a deep channel for the bristles because it would break through to the tube section. Smaller makes everything more challenging. I am more awed by watch makers than producers of huge machinery…

Perhaps rev 3 needs some more tweaking to leave more meat for a deeper brush channel without sacrificing clearance.

Guys I made one that works great. Unfortunately I have not gotten around to sharing it yet because it uses some components that are not readily available. But for the sake of contributing ideas back to the community you can have a look:

It took a few iterations to get to this point.

Here is the first version that did not account for the z rails, I had to cut off the support structure to make it work.

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The trick to this one is that it is easy to remove because, sometimes you don’t need dust collection or whatever. Just pull the entire nut assembly out vertically and it’s gone. I am planning on adapting this stainless steel rod and hex nut mount for an airblast at some point.

Edit: Also, sorry if I didn’t catch this earlier, but this is for the Primo version only.

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nice design. Unfortunately I have not upgraded to the primo…

@tealfixie that looks great! Do you plan to share the design? Did you made it In Fusion? Seems like a great implementation!

I do plan on sharing the design after I figure out how people can source a unthreaded hex hut with a tapped hole in the side for a grub screw. For me, was able to use the 7mm stainless steel shaft and the hex nut coupler from a discarded trampoline net hardware. The next best thing would be a threaded rod and hex nut, but it would not work as well without a grub screw. I’ll put it up on thingiverse when I get home later.

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Here is my current dust shoe solution. It is a prototype. It works well, but there are a list of changes I will be making for V2. The square tube has the same cross-sectional area as the vacuum hose and can be raised or lowered to place the shoe at the top of the work piece, and it is small enough to not take anything away from the X and Y cutting area. The smaller dust shoe in front was a experiment I ran a couple of days ago based on the question posed by this thread. I didn’t think a no-shoe solution would work, but I thought a shoe with a cutaway that allows me to see the bit cutting was worth a test. It worked almost as well as as the full shoe, but this shoe only works for longer 1/8" bits.

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Wow that looks really great! Do you have this shared anywhere? I’d really love to unify these efforts so we can combine our collective creativity and skill. Would be great if we could drive towards a best practice dust shoe.

If the designs happen to be in Fusion I’d be happy to lend a hand making them parametric to fit different spindles!

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“threaded rod and a nut with a grub screw”…how about a threaded rod and a pair of nuts, i.e. a nut and a lock-nut ( no, not a Nylok!).

“jam nut”?

Probably. Two nuts on same thread, tightened against each other.
In UK English(at least, as I learned it) that is a nut and a lock-nut.
Jam nut makes sense, so I guess that is the US version.
( I’m American now, but started out English, and still retain much UK vocab, esp for things I don’t often discuss with other Yanks. I buy pants, but wear trousers etc., and just don’t start on auto engine parts naming :face_with_symbols_over_mouth:)