Festool CT 25 Particle counts - doesn't appear to be filtering

[mino]

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- A HEPA filter is only as good as it's seal. The bosh unit has a gasket built into the filter, so that gets replaced each time a filter is changed. I believe this is how it works on the ct 26. The gasket was not a part of the CT 25 filter, so I could see the seal on these units degrading over time.
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I have a 2011 Protool VCP 480-L (a.k.a. one of the early models of the Festool CT 48 AC HD).

It was a vac that I got from a tool rentals as it had the top plastics broken, not worth of them repairing anymore.

Everything on the vac, excepting the motor which was very likely replaced a couple times given the high usage it got subjected to is .. original from 2011. Including the control electronics.

Long story short, the seal on the tub is as new /that is after 10+ years of heavy abuse by cheapo tradespeople who would not afford their own vac/.


Do not assume that just because junk 'seals' found on shop vacs and and other cheapo kit fall apart after a year or two, the Festool ones do as well. The same goes for their plastics, those are made to last 20+ years.

Tech-wise, from the 1980s on, it is a choice to make stuff from disintegrating plastics and degrading seals, a choice FT does not make as a matter of a policy given all their tools are sold with 20+ year lifespans presumed. Many users on here carrying on 40+ year tools from them.

Secondly, the only* seal you care about for HEPA and co is the one which is part of the main filter ... and that one you replace each time you replace the main filter. Not that the one would not last in elastic state for 10+ years. It does. Everything before that seal is in a vacuum zone and everything behind that seal is already after the filtration was done.

*) Yeah, with vacs that have AutoClean - creating overpressure pushes inside the tub - you do care about the tub seal as well, an order of magnitude less, but you do. See comment above for that one.

 

[Cheese]

This may be more towards those new to Festool, but one aspect of the Festool extractors that doesn't seem to get mentioned much anymore in the HEPA world is that the units themselves are HEPA rated - meaning that all the suction air that comes thru the unit is filtered and the unit itself is made so that it seals to prevent unfiltered suction air from exiting. Jut because you toss in a HEPA filter into a shop vac does not mean that all the suction air coming out will be HEPA filtered due to potential leaks in the units. If you truly want HEPA then you need to locate a HEPA unit - not just a HEPA filter.

Peter

I read an article somewhere on all of the details that Festool had to address to ensure their vacs are HEPA rated for the long term. The long list of seemingly small, insignificant items was stunning, certainly more than I was aware of and certainly more involved than just stuffing a HEPA filter in a vac.

 

[ReneS]

Re the air testing tool...

Seems to me you can test it's reliability even if you cannot test its validity, meaning the accuracy of the number that it produces.

Once you ensure that it produces the same number for the same or very similar condition, then at least you can compare different vacuums and extractors to each other.

So while you may not know the actual particulate count, you can know whether one machine emits more particulate, then the other.

 

[mino]

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So while you may not know the actual particulate count, you can know whether one machine emits more particulate, then the other.

Hate to burst your bubble, but this is false.

The core issue here is you do not know what the tool is actually measuring at any given point. In short, the only thing such a blunt measuring tool is useful for*) is time-comparative assessment of the same thing - the same vac over time sucking the same material in the same way in the same environment /impossible to guarantee, fail#1/ at different points in time. Things like looking for unexpected changes to known-behaviour systems, think indications of suddenly broken seals etc. Even there it is very tentative.

This type of a super-simple "particle meter" is, by its design, bunching together all kinds of particles and with unknown accuracy between them, to make it more fun. From the smallest to the big ones that would settle fast, from the harmless carbon dust from the brushes to the carcinogenic lead paint dust, etc. This means that the only thing scenario in which it can reasonably well measure something comparatively is if your dust environment has a static contaminants composition AND the air is not moving /much/ as any air movement will skew the results due to the way the internal laser uses timing for assessment.

Want to check if your neighbour burning garden garbage is affecting your air compared to the day before when he was not doing that - probably good-enough. Anything else more specific is a GIGO. Garbage /data/ in, Garbage /conclusions/ out.

ADD:
*) In the context of misusing it for assessing things it was never meant/designed to do, like the efficiency of specific devices, not mention their comparison. It is a good device for what it is meant for -a blunt assessment when you live near a dust source like a road and want to know when to ventilate the house. Or when your shop air is "dusty" - so can do something with it. Not for assessing how/why/how much it got so.

 

[Coen]

Once you ensure that it produces the same number for the same or very similar condition, then at least you can compare different vacuums and extractors to each other.

So while you may not know the actual particulate count, you can know whether one machine emits more particulate, then the other.

Not when you place those vacs in a dirty environment. As posted earlier; some vacs have a secondary (unfiltered) airflow of cooling air. If you start out in a dust environment, the airflow created by both the filtered exhaust and the unfiltered cooling exhaust will stir up settled dust that will go airborne + get sucked into the cooling inlet and be blown around. The position of intakes + outtakes + relative position vs dusty environment all play into that result.

Now, let's say you put all the different vacs into a clean 1 meter pipe (one by one) with on one side a sealed port for their hose that then sucks in tool-created dust, then measure at the end of the pipe... then you have something to compare.

 

[hello]

Not when you place those vacs in a dirty environment. As posted earlier; some vacs have a secondary (unfiltered) airflow of cooling air. If you start out in a dust environment, the airflow created by both the filtered exhaust and the unfiltered cooling exhaust will stir up settled dust that will go airborne + get sucked into the cooling inlet and be blown around. The position of intakes + outtakes + relative position vs dusty environment all play into that result.

Now, let's say you put all the different vacs into a clean 1 meter pipe (one by one) with on one side a sealed port for their hose that then sucks in tool-created dust, then measure at the end of the pipe... then you have something to compare.

People on this thread get very attached to their festool vacuum's filtering efficiency. The vacuum was 100% emitting something from the unfiltered cooling air. My garage smelled like burnt plastic. Additionally, the dylos units are pretty accurate for a consumer model. They are used by the EPAs citizen scientist program to monitor air quality.

@mino As a rule, anything mechanical can be compromised. Hepa filters and their seals can be compromised to the point that particles can escape capture. RRP rules require a dedicated vacuum for remediation work. You're not allowed to take a RRP vacuum to do work in a home without lead paint because it introduces an unnecessary risk.

 

[hello]

Tangent:

From a woodworking perspective, it's very contradictory that many shops use HEPA certified units for their hand tools/hand sanders, a Ridgid shop vac for general clean up, and canisters on their stationary dust collectors that are rated at MERV 11/MERV 12 (often used on drum sanders). For example, the Laguna "1-micron" dust collectors are MERV 12.

Many of these influencers will go on and on about a festool extractor and use their MERV 12 canister filter on their primary dust collector in the same youtube video.

Anyone have any luck finding a HEPA dust collector? I've only found Oneida so far.

Laguna B|Flux Dust Collector 110V 1HP Quiet Dust Collection | Woodcraft

Keep your workspace clean with the Laguna B|Flux Dust Collector, a 1HP 110V system offering efficient dust control in a compact design. Buy online or in a Woodcraft store!

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• MERV Rating: 12

MERV Rating	Particle Size in Microns (µm) with Average Capture Efficiency
1-4	3.0-10.0µm less than 20%
5	3.0-10.0µm greater than or equal to 20%
6	3.0-10.0µm greater than or equal to 35%
7	3.0-10.0µm greater than or equal to 50%
8	1.0-3.0µm greater than or equal to 20% 3.0-10.0µm greater than or equal to 70%
9	1.0-3.0µm greater than or equal to 35% 3.0-10.0µm greater than or equal to 75%
10	1.0-3.0µm greater than or equal to 50% 3.0-10.0µm greater than or equal to 80%
11	0.30-1.0µm greater than or equal to 20% 1.0-3.0µm greater than or equal to 65% 3.0-10.0µm greater than or equal to 85%
12	0.30-1.0µm greater than or equal to 35% 1.0-3.0µm greater than or equal to 80% 3.0-10.0µm greater than or equal to 90%
13	0.30-1.0µm greater than or equal to 50% 1.0-3.0µm greater than or equal to 85% 3.0-10.0µm greater than or equal to 90%
14	0.30-1.0µm greater than or equal to 75% 1.0-3.0µm greater than or equal to 90% 3.0-10.0µm greater than or equal to 95%
15	0.30-1.0µm greater than or equal to 85% 1.0-3.0µm greater than or equal to 90% 3.0-10.0µm greater than or equal to 95%
16	0.30-1.0µm greater than or equal to 95% 1.0-3.0µm greater than or equal to 95% 3.0-10.0µm greater than or equal to 95%
HEPA filter*	0.30µm greater than or equal to 99.97% Particles that are larger or smaller than 0.30µm are captured with a greater than 99.97% efficiency

 

[mino]

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@mino As a rule, anything mechanical can be compromised. Hepa filters and their seals can be compromised to the point that particles can escape capture. RRP rules require a dedicated vacuum for remediation work. You're not allowed to take a RRP vacuum to do work in a home without lead paint because it introduces an unnecessary risk.

You are missing my point here.

What I am stating is that quality rubber retains properties for decades. Many people are used to the disposable junk that is sold en masse and thus are unaware of this. That is why I mention it.

Further. For safety you never rely on the "it is new therefore it works" fallacy. You check and re-check. Never blindly trust.

Even further. A component that has provably worked for 10+ years and is provably designed for a 20+ years lifespan is more trustworthy than a one-time-use component where you run the realistic risk that after 5 years in storage it may have lost its properties without you being aware of it, not to mention manufacturing defects. That is why you check and re-check and never assume, as far as safety goes. Anything can fail indeed.

 

[Coen]

People on this thread get very attached to their festool vacuum's filtering efficiency. The vacuum was 100% emitting something from the unfiltered cooling air. My garage smelled like burnt plastic. Additionally, the dylos units are pretty accurate for a consumer model. They are used by the EPAs citizen scientist program to monitor air quality.

So in the end it was not a filtration issue but just cooling air going around, like I suggested five months ago?