CNC Dust Shoe Replacement

A while back I bought a new dust shoe for the CNC machine. I used it very little, and put it under the cart to try at a later time.

Well tonight was that trial. I switched out the boot on the machine with this new one, a design that directs the vacuum more towards the bit. I flattened a live edge slab, with 2 epoxy rivers. I have never had less clean up from the CNC before. Flattening slabs with my 2 inch bit and the existing dust shoe has always thrown debris everywhere, and caused a lengthy clean up time. Tonight I could barely tell I was using the machine. It took less than 2 mins to clean the machine afterwards, and the dust collection bin had all of my debris in it.

It does have a metal frame and uses a hex screw to clamp around the spindle. The frame splits in 2 with some spring clamps to allow easy bit change. Even my 2 in bit got nowhere near the frame, and the bristles help up great to the drag against my material.

I left it on the machine, and left the existing one on the side of the cabinet. I’m not sure if others will agree, but I think its an improvement.

@zackg I did zip tie the new air assist up higher on the z axis, so I could try this out. I’d be really curious if it cleared out aluminum chips better, but if memory serves me, you don;t use the dust collection while cutting. It didn’t seem like the air solenoid was permanently mounted, i hope you don’t mind me moving it.

Tagging @JoeN and @dannym, let me know what y’all think.


Yeah, I’m concerned the metal chips might damage the vac system. So I figure better to be safe then sorry.

One thing to consider when placing the air valve, due to the wet shop air it produces a moderate amount of water, at the valve body and on the nozzle arm. We need to make sure the water doesn’t get into the spindle.

I did leave the location flexible, so I’m glad you were able to make use of it. I figure there’s multiple needs, so we need to find a placement that works well.

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Very cool!

I can see where it’s a better profile for the bristles than what we’ve been using.

Steel dust shoes concern me a lot though. Reason being, if a steel shoe falls, then it’s quite plausible the carbide bit will strike it which can throw really hot sparks and cause a dust collector fire in seconds. I would say steel dust shoes just should not be used for safety reasons. I looked it over the other night, my feel of it was the attachment system didn’t seem reliable for its weight. That head can do some way aggressive motion at times and coming off seems like a very real concern.

I’m looking at similar ones maybe like this on Amazon

This one appears to be plastic. Non-sparking, lighter, and looks like better flow dynamics than the steel one. The front does come off to give access to the spindle taper.

I agree with the concerns about a steel shoe. I will say, i was running it last night at 300 inches/sec and the bristles had a decent about of drag on them. The shoe seemed very secure, and never came loose.

I like that plastic design, and it seems like the best of both worlds. I can purchase it if we’re in agreement on it.

I did measure the spindle- it calipered at 72.5mm, so I don’t quite know if the 70mm or 75mm option is best. Odd, that should be a common spindle size there.

Ah, had another thought.

The Z-axis can drop while unpowered, which is why we never leave the shoe on the head when we’re done. The front part of the bristles is designed to be easily removed, but another part with bristles stays with the head. Adding this to machine setup/closing procedure would require a hex wrench, keeping track of the loose bolt and nut, and also detaching the 4" dust port. That seems problematic for the broad user base here to install/remove every time and not lose parts. But we might come up with a stand or something? There are shaft brakes but they’re primarily designed for double-shafted stepper motors which we don’t use

FWIW, I did notice the spindle come down on the shoe, and the bristles seemed to hold it up well. For $30, and the huge savings on time, I’d be willing to provide one multiple times a year if it even wears out that fast.

I think the boot coming off should not be a big deal. The operator should be near the cnc router as it is running. I have spare bristles if we need to replace. I’m using a plastic version of the metal one and like it very much

Yeah. I got to look at it yesterday and it looks great. My only question is how do I take it off for when I want to go shoeless?

From the amazon listing, it looks like unscrewing the hex bolt will let you take the boot off, is that right? I use clamps on my jigs and the other boot interferes enough that I cannot use it. I’m guessing I’ll need to be able to remove this one as well.

One hex screw releases it from the spindle, same as the original shoe.

The metal dust shoe has more clearance when removed vs the current acrylic plate. The clearance issue only came into play when I was flycutting the table. The disconnected hose when the metal dust shoe is removed might be a problem

It was easy to take the metal shoe off. I put the old one on just to give the hose somewhere to go. Lets keep the hex wrenches in the plastic collet bin so there are always tools available to switch them out quickly.

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I used the CNC today for the first time since the replacement and I have to say I’m not sure I see the improvement. During the cut, it works fine, just like the last one did. Afterwards I tried to run the dust shoe along the bed to vacuum up the bed like I’ve done with the previous shoe and it just seemed to push the dust around rather than suck up the majority of it. Previously it would get everything in its path in one go, now I had to go over everything more than once and eventually just use the shop vac cart. Just my 2 cents

hmm. I didn’t think about that. I find that I don’t need to run the vacuum post job since it picks so much dust during.

You’d think it would be better in both cases if it was better it one. It could have been another issue too. The vacuum just didn’t feel like it was that powerful. Checked the can and all, looked good to me.

I wonder if the bags pores are clogged. We need to switch it to a pleat filter.

The pleated filters are impressive at first but they clog fast. The one on the dust collector for the other tools is constantly clogged, it lasts like a week. The pleated paper is expensive and officially supposed to be replaced, not cleaned. We’ve cleaned it a few times but it doesn’t last long and the paper is degrading.

The huge shaker felt bag is more reliable in the long run. The downside is they are physically bulky and generally require high ceilings unless you have a baghouse design, which is then laterally very bulky. But we have the high ceilings and can run a huge bag on a pulley that you can take down to clean. I’d say we need to switch the pleat filter on the other one to a big shaker and learn how to clean it.

I did see a time when people took off the probably-20-micron crap bag off the main DC and tried a 1 micron replacement. That would never work, 1 micron shakers are excellent but cannot be a drop-in, the same physical height would be grossly undersized.

Again, cleaning is required. AFAIK the CNC’s shaker hasn’t been cleaned in a long time and it is not flowing well. Clean it and it will outperfom the pleated paper for a longer period.

We need to train people in cleaning the bags. Some people say they just beat it with a bat or paddle. Others take it off, outside, and then inside-out, and then shop vac it or inflate it with Shop Vac exhaust.

Actually, not a bad setup to create- we need a big round plate to attach the locking band of the filter with it inside-out and attach a hose from a bouncy house blower and clean the filter that way.

I initially thought simply laundering it in a washing machine would be simplest, but people said it would open up the fibers and it won’t trap to 1um anymore. It seemed like people were speaking from speculation rather than having tried it, though.

I think the bristles are a little stiffer than the regular shoe. I have vacuumed with it before, and had to raise it about half an inch off the bed. I do agree with Joe, the mess afterwards is usually a lot less. Where the new shoe seems to shine is, working better with longer bits, especially with surfacing bits. No boot seems like it is going to be the 100% fix all, but like @Mollie said, it’s pretty easy to switch them out.

I have come across the suction not working well because one of the pipes top the cyclone of top of the dust collector has come off. It’s not always evident, because there is still low suction from the others. I’d check those pipes and also make sure they aren’t clogged.