Filters and Filter Fabric

[DreamDiver]

I have enough filters for now, but I'm a little frosted about the cost. A few filters for $15 seems like highway robbery when I know these things are stamp-cut into smaller pieces from relatively inexpensive filter fabric.

And buying pre-made filters from Amazon seems not much better.

Does anyone know a reliable direct provider of the most suitable hypoallergenic filter fabric so I can just make my own?

Can anyone think of a reason why not to do this?

Cheers,

Chris

[Pugsy]

Without knowing the specs for suitable filters I don't know of any way to go down the DIY filter road.
From some of the different filters I have see though...man the specs must be wide indeed.
I usually buy in large bulk and the per filter cost is less than 50 cents and I change the filter once a month.
I am sure the product is out there that these generic filter sellers are buying a huge sheet of and cutting up into tiny pieces.....but I have never seen it. Though I will admit that I haven't looked.

[palerider]

I have enough filters for now, but I'm a little frosted about the cost. A few filters for $15

You *do* realized that "a few" means *40* on Amazon?

If you change them every six months (which is the outside time that the clinician manual says) that's *twenty years* worth of filters.

How much effort do you want to put into cutting your own?

[LSAT]

I agree with PR...I buy a dozen pack from ebay and that's a 6 year supply for me. It outlasts the machine. Even every 6 months, my filters are clean.
12 filters for the S9/Airsense/AirCurve are about $8 with free shipping.

[DreamDiver]

Pugsy, PaleRider, LSAT,

Thanks for your replies.

Yeah... I'm really overthinking it. I've been looking closer at how they're made. The process is pretty niche.

When I look closely at the hypoallergenic version, it looks like it's three (possibly four) layers bonded together, similar to the parts found in a disposable surgical mask, but made to handle like a single thick fabric.

(See image below for fabric examples - not made exactly like our filters, but same fabrics.)

• Inside: spunbond polypropylene nonwoven layer - somewhat shiny waterproof to block vapor droplets - dot-pattern side, but white
• Middle: meltblown polypropylene nonwoven layer - micron-sized particle filtration - a little fluffy - there could be two layers of this.
• Outside: spunbond polyproplyene nonwoven layer - same dot-patterned white fabric as the inside

It appears the layers are not glued together but rather, as they're stamped, the fabric edges are precisely and quickly heated to melt the edges crisply together. That probably takes a very special machine to do that.

I've also seen some with just one shiny dotted spunbound side and a fluffy meltblown side, so it would be like the facing inside and middle layer of the above example. These are probably inferior.

The filter that comes with the S9 or AS10 is a meltblown polypropylene coarsely nonwoven single layer that filters only large dust particles and poorly at that. I keep it only as a backup just in case I run out of the other filters. The only advantage to this filter is that it can be washed and reused. That said, it does only the roughest job of actually filtering.

It's like the difference between one of those old-fashioned half-inch fiberglass filters for a whole house filter and a four-inch wide pleated hepa 11 whole-house filter. One keeps mostly bugs and mice out. The other keeps actual fine dust out.

Yeah. It's obviously just easier to buy the filters, especially if you get them from Amazon.

Thanks!

Chris

[DreamDiver]

I love how filter makers have absolutely no clue what these things are for, as indicated by these ridiculous images of people wearing a little nose-pluggy thing on Amazon. In my mind's eye, I see this sweaty guy under a ceiling fan in a sweatshop with a combover in a green visor and a fat cigar saying to himself, "yeah, that's what cpap looks like. Yeah, that's it. Let's put that into our amazon ad. Yeah..." Is it me, or do they look like they're pursing their lips?