When to change CT bags?

[NiteWalkerGR]

At a price of $419 the cyclone would have to replace 10 packs of bags (genuine) or 20 of the knock-offs.

That's assuming one buys the festool cyclone. You can have a very serviceable setup for around $100 using a dust deputy.

That said, I do agree bags are not really a cost issue. For my midi, I have around 35 bags because I found a seller on ebay clearing out boxes of festool bags for $25 each. I grabbed em all. And my midi is my mobile vac that doesn't see as much use as my workshop vac, where I have a dust deputy set up. So those 35 bags will last me years. Whereas in the workshop I'd be changing bags weekly if not for the dust deputy.

 

[JINRO]

Ordered Macam bag and arriving today.  It is a replica of Festool long life bag.  I wanted to try since it has opening slot is on side which will be much easier with emptying dust/chips.

 

[Crazyraceguy]

Agreed totally. Why would someone use a separator with a big vac like a 36 or 48?
When the cyclone is involved, all you need is the suction and filtration, the size of the bag (which is not supposed to fill up anyway) is irrelevant.
I would also think that having to deal with the separator in a van/jobsite situation would get old, as would lugging a bigger unit.
There would be an exception for drywall sanders and the auto-clean of course.

 

[ChuckM]

Snip.
Not much point paying for HEPA microfilters if one plans on compromising their filtration ability with compressed air ... just saying. It is possible to de-dust the PET microfilters with compressed air. But one needs to be carefull to not get too close to the filter. The air stream will punch (invisible) holes in the filter structure in no time, effectively destroying it as a filter. Snip.
YMMV

I could be wrong, but some people might've got the wrong idea about using compressed air to clean the HEPA filters after seeing that done in one of the Festool videos. Maybe Fine Woodworking or some other magazine has advised against using compressed air on HEPA filters as the damage done is invisible to the naked eye, and users might have a false sense of protection while using the filters.

 

[WillB]

some good input here....
I always felt the HEPA filters are the last trap for dust...  the HEPA determines what escapes the vac.  I have used the DD with the same bag for a long time, and I do occasionally check the HEPA filters, but they are always super clean.  Bags must be damn good, sometimes I just change them cause they are old.  They rarely have anything in them, at least visible.
The only time I had dirty HEPA when one vac w out cyclone... changed bag, had spillage, and it was not cleaned up, (stupid, we all get side tracked) so it ended up in the HEPA, a bit of compressed air and it was back... and point well taken, u cant blast these delicate filters, I shoot from far away, that is all it takes.  I rack my fingers over the filter to be sure the compressed air gets to most of the pleats.  i also use compressed air for my large drum HEPA in my Laguna P Flux vacs..those things get plugged, Laguna recommends compressed air.... i only use it occasionally, instead, I take my SYSVAC and vac it out, works great.   
Valid point about using these Festool Vac on n off job site, vs. those of us who only work in a shop and not in the field.  Different requirements.  If I was in the field, I would get a slightly bigger vac, no cyclone, way to cumbersome to deal with when transporting, at least the DD, prob. Festool Cyclone not as bad...  But as others pointed out, they are not mandatory, the Vac n Bag system is impressive, did that for 15 yrs without issue.  Nice to see these 3rd party bag makers like Powertec, will give them a try...

 

[luvmytoolz]

Agreed totally. Why would someone use a separator with a big vac like a 36 or 48?
When the cyclone is involved, all you need is the suction and filtration, the size of the bag (which is not supposed to fill up anyway) is irrelevant.
I would also think that having to deal with the separator in a van/jobsite situation would get old, as would lugging a bigger unit.
There would be an exception for drywall sanders and the auto-clean of course.

I do, I cut up a huge LPG tank and put a DD on top of it going to my CT36 for my bigger CNC machine. I have a long life bag in the CT that has only ever been emptied once (bought the L/L bag before realising just how effective the DD is), but the tank has been emptied numerous times. Granted the CT36 is overkill as I only run it around 1/2 power anyway, but it all fits nicely out of the way and just does the job.

 

[Crazyraceguy]

I noticed a bit of suction loss this morning....yep, brick. A lot of it was solid surface dust from flush-trimming that white wall from a couple of weeks ago. It was very heavy.

 

[Steve1]

I'm on my 3rd bag in 40 years, 2 still left in the carton!

The Dust Deputy on my CT-36 is so effective that I have not changed the bag in ages.
I was beginning to wonder if the very finest dust was getting through the cyclone and clogging the pores in the bag.  And maybe its time to change the bag just for that reason.

So maybe I am overthinking this.

No, my bag did need changing.
I was noticing the suction on my CT-36 seemed to be less than it used to be. 
So I looked at the bag, and it was maybe 2/3 full, but had been in there for probably a few years. 
Before I got the DD, I would leave it in there until I started getting sawdust falling out of the port when I pulled the hose.  At that point, the bag was totally full.
I replaced the bag and instantly it was obvious I was getting massively more airflow.

 

[Imemiter]

When you've accidently vacuumed a small lever off your RAS 115 and see that the replacement part will cost $52.  [eek]

 

[Cheese]

[thumbs up]

When you've accidently vacuumed a small lever off your RAS 115 and see that the replacement part will cost $52.  [eek]

[thumbs up]

 

[Crazyraceguy]

When you've accidently vacuumed a small lever off your RAS 115 and see that the replacement part will cost $52.  [eek]

At least you know where it is  [blink] which is better than "losing it" and not knowing where to look.
Sure wouldn't be much fun though.

 

[Imemiter]

When you've accidently vacuumed a small lever off your RAS 115 and see that the replacement part will cost $52.  [eek]

At least you know where it is  [blink] which is better than "losing it" and not knowing where to look.
Sure wouldn't be much fun though.

I planned to dig for the RAS lever this morning. It's a relatively new bag. There was so little in there I decided to get through with Friday's work and do the autopsy some time this weekend. The thought occurred to use the bag for another week or two, but no. Bags are cheap compared to a $52 part.

 

[mino]

...
They will actually keep sucking until the hose it full too. It has happened to me twice. Then I have to get a stick and plunge it back out. There is nothing on-board to warn you that it is getting full.
...

Late to the party, but worth mentioning for some:

If someone is in Europe, the CTM series vacs include an air flow sensor. The main purpose of it to warn the user when the bag is clogged for safety reasons. It works irrespective the bag being full or the hose clogged. In practice works like a "bag full" alarm.

These go about $100 above the CTL series which are equiv. to CT in US and most people consider it a waste of money for hobbies. I also considered it a gimmick. Not so much now.

With multiple people in a community shop - some of which do not notice a vac running from one turned off when sanding - it gives a peace of mind setup. We have a cheapo Makita vac for the chopsaw and it is a PITA to keep checking every week or so if the bag needs replacing ... Money allowing, it will get relegated to cleanup duties and a CTM 36 will take its place.