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What are the best vibratory blades for cutting plaster? Not just wood lathe, but also double boarded plaster with hard top coat

StillTendigits's picture

This is not so much for home building, but for home repairs.  I have recently dealt with three stories of a wood plaster chase to replace pipes, and also the question of hard coated board over board is due to a new exploration mission looking for buried utilities to determine replacement of a load bearing wall.

It is easy to say just use a tiger saw blade.  That ignores whtt else might happen as the coatings are removed, as in electric, plumbing supply, or even ductwork.  Surface pentration becomes next logical idea, but the hard coat makes anything non carbide or diamond an expensive waste of time and money.  Going to a diamond blade on a mini Grinder or Roto-zip style wheel, or even a circular saw means hours of dust shielding.  Most of these penetrations are short term needs in occupied spaces, so now you are killing the advantage of quick work.

I have gone to the trouble of using a Dremel little diamond wheel to get a start, then drag, then gently pry wood lathe at strategic points.  Yet while that worked there, exactly 12 feet away the dang plaster was litterall 7/8" concrete, at leasrt 3K psi.  Dead end of a hallway, low to a carpeted floor, it still took 30 minutes to cut with a helper on a shop vac at cut, two kids to make dust shielding, and a total of all involved for at least 3.5 hours to count tools in, clean up, and tools out.

The next closest solution I have found is a vibratory diamond to clear hard coat, and then a toothed cutter for the boards behind.  However, I cannot find a toothed cutter that can survive even that with the plaster cap already removed. (continuing with a diamond vibrator in there is a waste, not enough agressive cutting).  Is there a good solid manufactured product that can do this job on a low dust vibratory concept?

Thanks for any consideration; it would be good for a manufacturer to consider this instead of ripping us off on cheap cutters.  Paying extra is fine, as long as it really is an extra and holds up.

You might try using a grout (post #215843, reply #1 of 3)

You might try using a grout blade in a Multimaster.

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If you are cutting drywall or (post #215843, reply #2 of 3)

If you are cutting drywall or plaster board use whatever you have to make a hole. If you are cutting old plaster over wood lath don't use a saw blade at all. Sometimes any vibration will start a plaster landslide. We use a toothed diamond wheel in a grinder. It cuts like butter and caused no delamination at all. Keep your shop vac right next to the ginder wheel to reduce the mess.

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.

Still (post #215843, reply #3 of 3)

When using a grinder I've made a scoop type shroud by cutting up a plastic milk jug (half or gallon) and taping the hose end of the vac to the neck.

 Have also read but not tried a system using a large clear plastic storage container.  They made it almost like a contaminated work box with sealed holes for your arms, cord and the vac hose.  It was fastened to the wall over the work area.  They either cut out the bottom and used the lid to get the grinder in or vice versa......

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Remodeling Contractor just outside the Glass City.