Should I prefilter James Hardie Dust?

[Tom the Remodeler]

Greetings!

So, I am working on a LARGE re-siding project where I will be cutting close to 2,000 sheets of 4'x9' James Hardie siding. I am using a CT-26 to extract the dust from my saw. I am using the Fleece bags and HEPA filter.

Is this dust going to eventually work its way into the motor or other critical parts and wear out my CT?

Should I be using a Cyclone dust separator as a pre-filter, or will the Fleece bag and HEPA filter be sufficient to protect the rest of my CT?

Knowing the specific type of dust I am extracting, do you have any suggestions on how often I should be replacing my HEPA filter? For example, replace HEPA filter after every 20 fleece bags?

Thanks much, I look forward to your input!
Best,
Tom

 

[Brice Burrell]

The dust isn't likely to get past the HEPA filter.  I just pull the filter out once in while a tap it to knock the loose dust out.  On the other hand, a new filter every so ofter is cheap insurance. 

 

[tbellemare]

Do you get much in the filter, Brice? If so, can you tell what might have gotten past the bag? The bags are 5 micron filters and I'd be interested to know if you can tell what it might be that's getting past them.

I'm going to do some research and see if I can determine what particles are likely to be smaller than 5 microns. I found some articles a couple of years ago that were from European standards institutes that described the size of common airborne particles on jobsites. I'll see if I can find that info again.

Tom

 

[Tim Sproul]

Festools are built to be used.  Really used.  Not abused but really well used.  I wouldn't consider drywall abuse.  I wouldn't consider cement board abuse.

Have at it.

 

[tbellemare]

Well put, Tim!

Tom

 

[Tim Sproul]

Do you get much in the filter, Brice?

Not Brice.....and I only recently got a CT-26.  On my CT-22 and CT-33 with the paper bags, I never see dust on the filters.  Even doing a lot of drywall sanding.

 

[tbellemare]

I've sanded drywall, all sorts of wood, concrete, mortar, aluminum, plastics, steel, iron, paint, glue, composites, epoxies (plus epoxy resin composites), marble, granite, and a lot of limestone. I've never had anything that I could quantify in the filters.

That's why I want to see if I can find this European study. I'm pretty sure I can if I try hard enough.

Tom

 

[FulThrotl]

Festools are built to be used.  Really used.  Not abused but really well used.  I wouldn't consider drywall abuse.  I wouldn't consider cement board abuse.

Have at it.

i've got a 33 that i've been using on the original filters for over 3 years now.... always use a
bag. the filters seldom have much on them... take them off, whap them against each
other a few times to knock most of it off, and keep going....

probably half of what goes in the bag is drywall dust and general
construction filth. i've taken the bag out when it's completely full
of drywall dust and weighs about 30 lbs.

depends on the paper or cloth used in the filter, and if it's dry or oiled media,
but K&N filters used for off road racing use an oiled cloth that filters better the
dirtier it gets. you shake off the loose dirt, and spray some more filter oil on
them, and they run bestest with a quarter inch of dirt on them...

what is the best test is how much dust build up is in the discharge port on
the bottom of the unit.

if you use the disposable bags, your vac will probably never be able to tell
the difference.... also, cooling air for the motor is drawn into the vac independently
from waste air, so it's not full of grit.

 

[Ken Nagrod]

Do you get much in the filter, Brice? If so, can you tell what might have gotten past the bag? The bags are 5 micron filters and I'd be interested to know if you can tell what it might be that's getting past them.

I'm going to do some research and see if I can determine what particles are likely to be smaller than 5 microns. I found some articles a couple of years ago that were from European standards institutes that described the size of common airborne particles on jobsites. I'll see if I can find that info again.

Tom

I couldn't find the chart I used to have from SATA for their filtering systems that gave that kind of information, but I did find these charts and info on the net:

Particulate sizes

Particle sizes

Particle sizes of airborne allergens

 

[peter halle]

Tom,

I have never worried about any dust affecting the CT-22 that I have.  I have just recently started using a cyclone (Dust Deputy Deluxe) ahead of the CT and am glad that I did.  After filling up 1 42 gallon trash bag of wood dust, dust, chips, drywall dust, etc. and having a vac bag separate while in use, I have virtually no dust inside the CT or the bag.  At $80 for the Dust Deputy versus $5 a bag I figure that I am well on my way to paying for the cyclone.

Peter

 

[Sparktrician]

I've found that using the Dust Deputy with my CT-22 makes a huge difference in bag life, especially when sanding drywall.  The dust clogs the paper bags very quickly without the DD, but when the DD is in line, it collects a very significant majority of the dust, making the bags last far longer.  I would suggest that you could anticipate a similar effect when dealing with Hardie Board. 

[smile]

 

[Brice Burrell]

Do you get much in the filter, Brice? If so, can you tell what might have gotten past the bag? The bags are 5 micron filters and I'd be interested to know if you can tell what it might be that's getting past them.

I'm going to do some research and see if I can determine what particles are likely to be smaller than 5 microns. I found some articles a couple of years ago that were from European standards institutes that described the size of common airborne particles on jobsites. I'll see if I can find that info again.

Tom

Tom, I get very little in the filter after a 4-5 bags.  I'd say MDF dust is biggest culprit.   

 

[Brice Burrell]

I couldn't find the chart I used to have from SATA for their filtering systems that gave that kind of information, but I did find these charts and info on the net:

Particulate sizes

Particle sizes

Particle sizes of airborne allergens

Ken, your links are proof that the HEPA filters are largely overkill for wood working and most everyday uses.  I've said that numerous times on here in the past and people wanted to run me out of town for it. [blink]

 

[tbellemare]

Thanks, Ken!

Since the bags are 5 micron filters, some common particles can get past them, including some cement dust.

As Brice points out, the standard filters, at 1 micron, will handle almost anything that a CT is meant to do. It seems that it won't handle lead particles because it says they are 0.1 - 0.7 microns. I guess that's where a HEPA filter is really useful.

Tom

 

[Brice Burrell]

Thanks, Ken!

Since the bags are 5 micron filters, some common particles can get past them, including some cement dust.

As Brice points out, the standard filters, at 1 micron, will handle almost anything that a CT is meant to do. It seems that it won't handle lead particles because it says they are 0.1 - 0.7 microns. I guess that's where a HEPA filter is really useful.


Tom

Well, I'd guess that's pure lead, lead suspended inside paint would likely be a different story.

 

[Tom the Remodeler]

Thanks for your input fellas!

I checked my HEPA filters today and they DEFINITELY have a fine film of dust on them. The dust is a kind of a grayish reddish color, so it's likely mostly concrete dust and maybe some Bondo. But, as stated above, I'm sure next to none of the dust is making it past the HEPA filter.

I was looking at the Dust Deputy cyclone, but my concern is that would one more thing to try to cram into the van, which is already just about full.

I had a very nice conversation with my local Fes Rep and he reassured me that I should be fine, just keep an eye on the main filter and make sure it's in good shape.
Best,
Tom

 

[TA455HO]

I've been doing 6.5" Hardie plank siding and also their Hardie backerboard beneath tile and the Snapper Shears work really slick. Quiet as a sewing machine and no dust created whatsoever. And it is quick to cut most any shape. I was cutting the cement backerboard in a kitchen and there wasn't a trace of dust anywhere. Everybody makes them now but at the time they were one of the only choices.

http://www.amazon.com/PacTool-International-SS204-Cement-Siding/dp/B001MUSY6E/ref=sr_1_1?ie=UTF8&qid=1326735344&sr=8-1

Here's the DeWalt flavor. Its head rotates 360 degrees which might be a nice feature but I haven't had the need yet.

http://www.amazon.com/DEWALT-D28605-16-Inch-Variable-Cement/dp/B000H2QPFA/ref=sr_1_1?s=hi&ie=UTF8&qid=1326735434&sr=1-1

A single set of blades is supposed to be good for up to 4 average sized homes worth of siding. Blades are typically reversible for double-duty.

 

[Kev]

I've been doing 6.5" Hardie plank siding and also their Hardie backerboard beneath tile and the Snapper Shears work really slick. Quiet as a sewing machine and no dust created whatsoever. And it is quick to cut most any shape. I was cutting the cement backerboard in a kitchen and there wasn't a trace of dust anywhere. Everybody makes them now but at the time they were one of the only choices.

http://www.amazon.com/PacTool-International-SS204-Cement-Siding/dp/B001MUSY6E/ref=sr_1_1?ie=UTF8&qid=1326735344&sr=8-1

Here's the DeWalt flavor. Its head rotates 360 degrees which might be a nice feature but I haven't had the need yet.

http://www.amazon.com/DEWALT-D28605-16-Inch-Variable-Cement/dp/B000H2QPFA/ref=sr_1_1?s=hi&ie=UTF8&qid=1326735434&sr=1-1

A single set of blades is supposed to be good for up to 4 average sized homes worth of siding. Blades are typically reversible for double-duty.

Because I cut very little of this stuff, I've always used the large manual shears. If I was faced with cutting a lot - I would certainly use power shears such as these and not a blade!

 

[Tom the Remodeler]

I agree that the shears work well for cross cutting Hardie planks. However, I am processing 4'x9' SHEETS of 5/16" Hardie siding, so shears simply don't work well for this application. I do appreciate the suggestion though, I'm all for finding easier ways of doing things!

I've attached a picture showing what many of my pieces look like. So, this sheet alone has probably 16 linear feet of cutting, now multiply that by 2,000 sheets and you get some idea of what I'm up against.....  [eek]
Best,
Tom

 

[Kev]

I agree that the shears work well for cross cutting Hardie planks. However, I am processing 4'x9' SHEETS of 5/16" Hardie siding, so shears simply don't work well for this application. I do appreciate the suggestion though, I'm all for finding easier ways of doing things!

I've attached a picture showing what many of my pieces look like. So, this sheet alone has probably 16 linear feet of cutting alone, now multiply that by 2,000 sheets and you get some idea of what I'm up against.....  [eek]
Best,
Tom

I see - not a project I'd be envious of doing!