Mask variables

I've had pretty good luck with the QuattroFX+padacheek liner, although, to make it work without leaking it has to be extremely tight.

I also have a Mirage Quattro I keep trying because it's so much roomier inside - also with the liner - also has to be very tight.
What I can't understand is why the machine works totally different with each mask. With the MQ it pumps much more violently on each inhalation cycle and then cuts it off too soon, leaving me gasping. With the QFX it does none of that! How can that be??
They both seem to have the same number of vent holes, etc.

My machine works pretty much the same for either mask, but what I did notice is that the hose was DIRECTLY in front of my nose and closer to it with the FX, so I was much more aware of the airflow and found that slightly uncomfortable. There's more distance in the Quattro, and also more volume for the air to spread out, so it lessens the feeling of being in a wind tunnel.

As for the fitting, NEITHER mask should be tight. Take a look in my signature for the "Taming the Mirage Quattro"--the same applies to the FX. Both are AIR CUSHION masks, and the air cushion can't work correctly to give a good seal if it's mashed up against your face. It takes some experimentation to find the right adjustment--and if your machine is an auto you need to be doing the adjustment at the HIGHEST pressure in your setting range, so you don't have a blow out when the pressure goes up.

If you do need to tighten anything at all on these masks, tighten the bottom straps--try to leave the top straps as loose as possible so that the air can really fill that cushion around your nose and prevent pressure and leaks.

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Ditto what Jan said. I used to use the QFX and when it was too tight it was leak city. You have to find the proper balance of not falling off your face loose and just snug enough. Read her taming posting and you will do okay.

As far as why the violent difference in the pumping, I have no idea. What pressure range are you using?

John

I was thrilled to find Janknitz's secrets to fitting these masks and read the article 3 times a number of months back, when I first got involved in such things. Beginning with everything very relaxed and gradually tightening just until the leaks stop. That's how they turn out to be very tight. And, as so many have reported here, as the straps stretch they will have to be tightened more all the time. Mind, this is with Padacheek liners, which was supposed to help. I think I never had a chance without the liners.

My pressures, when I can see the screen, are jumping between 12.5 and 9.5 (inhale/exhale).

Another question: Why should my pressures be so much lower in the morning than starting in the evening? I can't really tell how much lower - that stuff flickers pretty fast on the screen, and my eyes take quite a while to focus in the morning. But I could swear they are at least 3 points lower in the morning.