neato HEPA filter DIY mod v1

[fetish]

I'm a relatively new neato owner - mine just arrived 3 weeks ago and I love it to bits. The way it navigates is just awesome. And the fan unit is literally the best choice for its size.

BUT!

I've been thinking for quite some time now that the little filter provided is next to useless and lacked proper engineering.

1) it's leaky, causing fine dust to spread everywhere when i remove the bin

2) it chokes often. due to small surface area of filter and no pre filter. they should get a proper filtration engineer to improve on it.

3) it's poorly designed. in fact, the entire bin chamber is badly designed. look at the roomba aerovac bin - at least somebody is thinking of better ways to manage airflow and dust control. the neato's bin is as sophisticated as a waste paper basket.

4) the filter material is crap.

So being a tinker by nature, I set about making my own HEPA filter.

Here are the pics of Neato HEPA v1






Basically I cannibalized a HEPA filter off my black&decker cyclone vac. 1 filter yields enough material for 2 neato filters.
Then I used silicone and some thin cardboard to seal the edges.
lastly I fixed a fine semi rigid insect mesh over the top as a form of prefilter to prevent large debris from choking up the airflow.


Testing it made made one thing clear:

neato is limiting the suction power of the fan on purpose by design. because of my filter, my resulting airflow is estimated to be twice that of a normal clean original neato filter. and the neato stopped working with an error message asking me to check the bin because it thinks I left the filter out!
I had to place paper and oil filters to obstruct the airflow enough for the neato to work properly (estimated blocking off 60% of the airway)
noise wise, I would say there's not much difference. us neato users are quite used to the sound of its vacuum.

talk about hardware potential!
it's like operating dual i7 hex core CPUs with only 2gb of ram without any heatsinks.

Hope you guys find this useful.

If the neato folks are reading this, pls pls pls pls give me a firmware with the air flow limitation removed so I can see how this baby can fly.

[fetish]

Actually, since the normal vanilla filter is inefficient, doesnt a better filter technically equals lower power consumption via fan power modulation scripts?
The delta fan draws 38w at 12v *3A when running at full power, which is a massive power drain. A simple fan speed control should potentially double the neato's area cleaning capacity without a recharge.

[piokrza]

Interesting idea! I'm curious how you gonna clean the space in between the mesh and hepa

[vic7767]

It would probably be easier to make a separate pre-filter to install in front of the hepa filter.

[fetish]

Interesting idea! I'm curious how you gonna clean the space in between the mesh and hepa

Well since I've been cleaning my office so often there wasnt enough dust, so I sent it to clean the outdoor corridor instead.

The amount of crap I collected was crazy but the airflow was good throughout. But I guess if I were to go to the extreme, I've to think of how to mount an anemometer to the exhaust to measure the airflow.

Turns out most of the dust that gets past the mesh comes back out with a few taps from behind.

I'm still at crossroads about designing a fully disposable filter or semi disposable (more durable). But I'm leaning towards the semi disposable option due to the long life of the HEPA filter material.

Maybe v1.1 I'll make a removable mesh to aid fine particle removal.

[fetish]

It would probably be easier to make a separate pre-filter to install in front of the hepa filter.

yea that did cross my mind. but I guess I got distracted by the tv (topgear was on) that I ended up applying the silicon onto the mesh thus.

[firelog1101]

Very nice indeed, also an interesting discovery on the air flow limitation programming. However, I believe this feature may have been included with a later firmware update, I happen to recall someone mentioning months ago that XV-11 doesn't have a feature to detect when the filter is off (only when the whole cartridge is off).

I'm not well versed in pressure systems, but wouldn't this intentional programming result in less suction capability?

[piokrza]

Very nice indeed, also an interesting discovery on the air flow limitation programming. However, I believe this feature may have been included with a later firmware update, I happen to recall someone mentioning months ago that XV-11 doesn't have a feature to detect when the filter is off (only when the whole cartridge is off).

I'm not well versed in pressure systems, but wouldn't this intentional programming result in less suction capability?

Exactly. My Neato SW is 1.1 and he can work without the filter.

[fetish]

i see.. then that makes sense, because filter detection should always be a hardware interface thing, not a software band-aid.
but in this case i guess it's either the software patch or hardware revision, which will be much more costly.

then again, the detection script is practically useless because IF the filter is not there and the neato powers on, all the dirt and stuff would have already been sucked into the centrifugal BEFORE the airflow reaches the critical detection level. hmmmmm...

[firelog1101]

I imagine its use was intended for those that forgot to replace the filter after cleaning the cartridge.

Sure the fan would suck up some dirt that doesn't belong there, but it's not nearly as bad as the robot continuing on its run and sucking up all sorts of debris into its fan.

[JEfromCanada]

I imagine its use was intended for those that forgot to replace the filter after cleaning the cartridge.

Sure the fan would suck up some dirt that doesn't belong there, but it's not nearly as bad as the robot continuing on its run and sucking up all sorts of debris into its fan.

Yeah, if the detection is done during the initial "jet engine" power-on sequence, then the alarm would be raised before Neato actually starts moving along the cleaning path.

[djos]

Great Job Fetish! really nice work!

[fetish]

Thanks djos~

hearing so many members downgraded to 2.0, i figured I might as well try it too...

and the airflow detection script is not there! WOOHOOO!!
I just had my full powered neato run a cleaning cycle and yes this baby pulls more air than most handheld vacs, putting it between handhelds and household class.

I've also notice the spot in the bin chamber between the filter and the fan unit being cleaner now due to better seal and airflow. AND there's no longer any debris trapped at the bottom of the chute connecting the beater brushes section to the bin. There used to be a whole mess of large/heavy debris stuck there when i'm on the normal filters due to insufficient power to draw them into the bin itself, and they all come back out when i move the neato ever so slightly when it's off.

Navigation is a lot smoother on 2.0 compared to 2.1 somehow, with less overlaps. I figured this would work since the neato is a vac and not a sweeper like roomba, the suction should affect some area around the beaters to be cleaning as effectively as a direct overhead pass.

happiness.

[djos]

Nice, so when can we buy your HEPA filters?

[fetish]

Nice, so when can we buy your HEPA filters?

now that's a tempting thought. lol.

But i'll probably post up some instructables after i'm done with v1.2 which has the replaceable prefilter.

[djos]

Thanks fetish, I look forward to it.

[Geppo]

Great job, Fetish!
I think the lack of an HEPA filter is one of the weakness of the XV-11, but what I truly long for is also a replaceable dirt paper bag!
Emptying the debris bin is the worst part of the job and the only effective (and clean) mode it to use another vacuum cleaner (with bag and HEPA filter, of course)!

[fetish]

Great job, Fetish!
I think the lack of an HEPA filter is one of the weakness of the XV-11, but what I truly long for is also a replaceable dirt paper bag!
Emptying the debris bin is the worst part of the job and the only effective (and clean) mode it to use another vacuum cleaner (with bag and HEPA filter, of course)!

I did think of a dust bag but fabricating one for the chamber of the neato is gonna be a pain.. I might go around looking for some premade ones but until i run into one that fits, or members here has some links to one, i'll leave the idea on the shelf.

further down the pipeline might be a cyclone chamber design much like dyson's but that'll probably be v2 or v3.

for the time being i'll be working to try making the hepa unit betterfasterstrongereasier. so peeps all over can build their own.

[mtbook]

Thanks for the great idea! I spent the weekend building my own HEPA filter and, after some trial and error, am very happy with the results.

Since I wanted to have a removal prefilter, I decided not to add any metal grating but instead use dryer sheets. I drape the dryer sheet around the filter before I snap it in which locks the sheet in place. It's cheap and does the job pretty well. I go for the non-scent ones but you can just as easy make your home Bounty fresh

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Edit: Pictures!

Silicone sealant does a fantastic job air-sealing the filter to the cardboard frame (thanks for the tip, I would have never thought of using that)

Dryer sheet, cut in thirds

When the filter snaps in it clamps the dryer sheet in place

Dryer sheet snug against the HEPA filter

[fetish]

Thanks for the great idea! I spent the weekend building my own HEPA filter and, after some trial and error, am very happy with the results.

Since I wanted to have a removal prefilter, I decided not to add any metal grating but instead use dryer sheets. I drape the dryer sheet around the filter before I snap it in which locks the sheet in place. It's cheap and does the job pretty well. I go for the non-scent ones but you can just as easy make your home Bounty fresh

cool man! attach a few pictures!
had been super busy these few weeks so no new dev on my side.