Actual functionality of CT MIDI's filter clean lever?

[silence2-38554]

I've had my CT MIDI for a couple years now, used exclusively in my woodworking shop with the separator in front.  This summer, I've had to embark on a lot of masonry-related work on our property, leading me to research (and want to buy) a CT 36 AC.  This leads me to my question-

I have never pulled the filter out of the MIDI & thought it to be in need of even a light cleaning, as I always use it with a bag.  As far as I can tell, there is no plastic bag equivalent for the MIDI as there is for the 36 AC when working with drywall / masonry dust.  The concept of the AC and Manual Clean lever seems to be identical between the two units, blowing air back through the filter to clean it.  So then, if the MIDI is always to be used with a bag, why even include this cleaning function?  If I were to use the vac without a bag, could I use it for sucking up mineral dust if I regularly pull the filter clean lever & plan on replacing the filter by the end of the job?

Fingers crossed for clarification & insight

 

[squall_line]

The cleaning method for the MINI-I/MIDI-I involves plugging the end of the hose and then manually pulsing the lever.  It's not recommended as a replacement for the true auto-clean function of the AC machines.

Some good reading here:
https://www.festoolownersgroup.com/festool-tools-accessories/ct-midi-(2019)-clean-function/
https://www.festoolownersgroup.com/ask-festool/festool-dust-extractors-'dedusting'/

 

[Coen]

So then, if the MIDI is always to be used with a bag, why even include this cleaning function? 

Because some particles escape the bag and end up clogging the filter, the latter problem being "solved" by the clean function.
Also other particles will be hugging the bag' ceiling, also solved by this clean function.

Keep in mind everything is smaller with the Midi than with the 26 and up. Meaning less filter area, less bag area, etc. So easier to loose suction power.

When I use my CTL 26 for wood shavings, it fills the bag to 100% without any noticeable loss of suction power, right up until the hose starts to fill up. When I do hollow coring in sand-lime brick, masonry, concrete and then the wall chasing in the same... the drop in suction power becomes annoying long before it's 75% full.