drywall dust - how much does it get?

[Flaky]

I recently bought a Rotex 125 and CT Mini.  It worked great on floor sanding, but when I tried it on joint compound on a wall and ceiling it didn't collect much of the dust.  Does it work better on sanding paint on vertical surfaces than joint compound?  I read here that the Dust Deputy helps to reduce the amount of dust reaching the vac, but does it decrease the amount of dust thrown off by the sander?  If not, what would be a better system to use? 

 

[Administrator_JSVN]

Welcome to the forum.

The Rotex and CT Mini should provide very good dust collection, even with drywall compound. Drywall dust is finer, and therefore should be easier for the machines to collect in theory. Can you tell us what grit of sandpaper you are using and whether the surface is flat or irregular (curved, etc.).

Per our warranty: Festool does not condone nor support the use of any non- Festool engineered, designed, and manufactured accessories or consumables with Festool products. Use of any non-Festool products may affect performance or void the warranty. Festool is not responsible for any damages or losses incurred and user assumes all risk and responsibility with non-Festool derived products.

Shane

 

[Brice Burrell]

Welcome to the FOG!  I wouldn't use a Rotex for sanding drywall because the balance isn't ideal.  What I mean is the elongated body of a Rotex sander makes it harder to balance or hold perfectly flat for extended periods of time on walls and ceilings.  The problem with not holding the sanders flat against the wall/ceiling is the ease of gauging on the soft surface of drywall compound-also, it allows more dust to escape.  

I much prefer the DTS400 or ETS125 for this task.  I'll slow the sander down to maybe speed 4 or so and I'll start with the suction about mid way on the vac and tweak from there.  

 

[Administrator_JSVN]

Definitely good point about balance, Brice, and that it could allow dust to escape if the sander isn't flat on the wall. An interface pad would also be an option to help with that. It would also feather the compound better.

 

[AlexThePalex]

I don't care about the balance, because I never seem to have a problem of keeping them flat, but I've found the Rotex sanders are not that good with drywall sanding as far as dust collection is concerned.

I've used my RO150 and a RO125 and dust was spewing everywhere. Maybe it's because the rotex takes off so much at once, or maybe it's because it just doesn't work as well with drywall dust as it does with paint/wood dust, I don't know. The end result was a big mess.

On the other hand, I've found that orbital sanders like the DTS400/RTS400 and the RTS300 work marvelous with drywall. Very good dust collection and they take off enough material to make it seem to go fast. I mostly use the DTS on drywall, and dust is at an absolute minimum. I mostly use granat 120 to 180. Just tune the DC down or your sander will stick to the wall like a vacuum clamp.

So I basically agree with Brice. I also have the ETS 125 and that one also does a fine job on drywall.

 

[Administrator_JSVN]

Interesting, Alex. I don't recall reading others commenting about the Rotex and drywall dust in a negative way. Granted, I've only used mine RO 150 for small patch jobs, but I've never had an issue at all. Same with my ETS 150, which I recently used for some patching.

As much as a I like the DTS, I haven't bought one yet. It really is one of my favorite sanders we offer.

 

[Kev]

Locky made a video of sanding plasterboard with a RO150 and it appeared to work quite well (the video is on here somewhere).

I personally use ETS150 and DTS400 on plasterboard because I have the choice.

I've always experienced great dust collection with the RO90 and RO150 ... but I've never sanded plasterboard with them ... and I can't comment on the RO125 as I don't own one.

 

[tjbnwi]

I can see loosing more dust in the aggressive mode with the RO, but in the random orbit mode I can't see it being an issue. The orbit is the same as the ETS 150-5, and that works very well on drywall compound.

If you're using a Rotex in the aggressive mode on fresh compound, I think there are other issues that need to be corrected.

Tom

 

[Administrator_JSVN]

Agreed, Tom. Use random orbit for drywall with the Rotex.

 

[Flaky]

Great forum!  Thanks for all the replies. 

Shane, the disc I was using was 150 grit and the surface was sheetrock with joint compound that had already had the peaks sanded down by hand.  I was in the random orbit mode and but didn't have the machine flat to the surface, trying to feather the edges only.  Can see how that would make a difference.  If I get a big wallboard job I'll switch to a DTS or ETS if necessary. 

Used the RO125 again today sanding solid stain off a deck - Excellent!

 

[Administrator_JSVN]

Like I mentioned in my earlier post, check out the interface pad. They can help you out with the feathering, but also keeping the abrasive flat on the wall. I'm no expert on the topic, but we have some drywall/paint guys on here. But, I tend to hit around the circumference first and then pass over the entire patch/joint. That helps feather the edges some. Others may have better/other techniques that could help.

http://festoolusa.com/power-tool-accessories/sanders/pads/interface-sander-backing-pad-for-ro-125-sander-d125-1-pack-492271

While this video isn't demonstrating a drywall application, you can see the effect of using the interface pad. It allows the abrasive to have some give.

 

[AlexThePalex]

Interesting, Alex. I don't recall reading others commenting about the Rotex and drywall dust in a negative way. Granted, I've only used mine RO 150 for small patch jobs, but I've never had an issue at all. Same with my ETS 150, which I recently used for some patching.

Well, maybe it's one of those differences between Europe and USA again I forgot about. I guess when Americans talk about sanding drywall it's mostly about filling up the seams between boards with some filler. I agree, when you sand that, there's not much dust with the Rotex either. This technique of drywall is used here sometimes, and I've done work like that a couple of times.

But mostly here drywall means that a full layer of plaster 12-20 mm thick is applied over the boards, because we generally don't leave drywall up just as is. It's regarded here as a basis, which has to be finished by a layer of plaster to make it stronger and look better. Sometimes I have to repair those layers, and because my mudding skills aren't that great I often have to sand a bit to get it flat. It's those situations I refer to when I talk about it getting really messy.  

 

[peter halle]

The technique also will create very different results with any of the round pad sanders.  If you are sanding and going from left to right you will collect more dust than if you are going right to left.  Also, if you are like me and use your hand to test for smoothness while you are sanding, don't lift the sander away from the surface, move it out of the way and keep it on the wall so you don't release any dust mid stream.

I noticed these items back when I had a helper.  I could sand like above and collect most of the dust.  He would sand differently and there was considerably more dust on the floor.

Peter

 

[jacko9]

Interesting, Alex. I don't recall reading others commenting about the Rotex and drywall dust in a negative way. Granted, I've only used mine RO 150 for small patch jobs, but I've never had an issue at all. Same with my ETS 150, which I recently used for some patching.

Well, maybe it's one of those differences between Europe and USA again I forgot about. I guess when Americans talk about sanding drywall it's mostly about filling up the seams between boards with some filler. I agree, when you sand that, there's not much dust with the Rotex either. This technique of drywall is used here sometimes, and I've done work like that a couple of times.

But mostly here drywall means that a full layer of plaster 12-20 mm thick is applied over the boards, because we generally don't leave drywall up just as is. It's regarded here as a basis, which has to be finished by a layer of plaster to make it stronger and look better. Sometimes I have to repair those layers, and because my mudding skills aren't that great I often have to sand a bit to get it flat. It's those situations I refer to when I talk about it getting really messy.  

In the States that's called Lath & Plaster.  Very seldom used in new construction but you run into it doing remodeling.

Jack