In the end there would be dust all over you, all over the floor and all over everything in sight.
Now with the advent of HEPA filters you can properly filter your vacuum, using the right attachment and a simple dust mask -you can eliminate most of the dust right at the point of creation.
The first key to this system
The HEPA filter. Shop Vac now offers a HEPA filter for most of it's vacuums for wet and dry pickup made by Gore Industries. If you don't want the wet pick up capability, they also offer a dry pick up only version for a few dollars less. The air that passes through the collection back is then filtered with the HEPA filter on its way out. Shop Vac makes a specific bag for drywall dust collection ("drywall collection filter bags"), they are yellow in color and come in 5-8, 10-14, and 16-22 gallon sizes.
The second key to this system is:
The vacuum sanding attachment. I have tried a couple of these and the best blend of cost and effectiveness is the hand sander made by Fiba Tape. The hand sander attachment connects to the vacuum without tools. There is no water bucket setup with this dry pick up system, it's just vacuum and attachment.
Hand Sander or Pole Sander
Fiba Tape also makes a pole sander which is a telescoping 3' - 6' fiberglass pole using the threaded collar locking system. This pole sander works pretty much like a standard pole sander with a vac hose attached to the end of it making it a bit more stiff than a standard pole but still workable.
With either the hand sander or the pole sander you will be using sanding screens not regular sand paper sheets. Sanding screens allow the dust to be drawn through them into the vacuum. You need to use a lighter touch when sanding with sanding screens, especially when used in conjunction with the vacuum suction of the dust free system. If you are a little heavy handed you will scratch the drywall mud you are trying to smooth out. Pull the sander attachment off from time to time and vacuum the sanding screen to avoid build up of particles on the screen wihich will cause scratching of the drywall compound.
Note: Dustless sanding systems are not intended for lead paint or other hazardous sanding activities. See EPA and the RRP rule guidelines for sanding in pre-1978 homes and best practices when distrubing lead based paint.
Dust free sanding should be the goal of any drywall repair and finishing job. What used to be impossible, has become a possibility with the advent of HEPA filters and some ingeniously designed vacuum attachments.
It is worth noting that while it is not absolutely, totally dust free it is very close to that.
No more mess
Long gone are the days when you had to cover everything in sight with plastic and put on a coverall and you let 'er rip with the pole sander.
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"the right way to buy
The definition of a HEPA filter is one that will filter 99.97% of all airborne particles, which are 0.3 microns in size or larger, which is fine enough to trap even drywall dust.
There is one "trick" to using the HEPA filter for this type of vacuuming, you have to "pre-filter" the bigger particles or you will end up with a clogged vacuum with no suction. Pre-filtering is done by using a collection bag upstream from the final HEPA filter. The collection bag traps the bigger particles and yet, still allows air to pass through it so that your vacuum isn't choked.
Vacuum Sanding Demonstrated
Hyde Dust-Free Drywall Sander
Sanding new drywall or drywall repairs creates a LOT of dust. Eliminate drywall compound sanding dust at the point of generation.
Dust Free Sanding part 1
(Dustless Drywall Sanding Systems for Sanding Drywall Compounds and Spackle)
Painting and Decorating Concourse
HEPA filters for Shop Vac brand and other shop vacuums
Vacuum Sanding Attachments
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