Replies

1. 
   caseyr | Dec 14, 2003 07:51am | #1

   I recently talked to the Hardi rep who was doing a demonstration at the recent JLC Live in Portland. One option would be the cement board shears such as by Porter Cable, Knipex, and Snappit. These run about $200-$225. They make a clean cut and can cut fairly tight curves, but the rep talked me out of getting those because they tend to be so slow. He recommended using a jig saw or using the circular saw with a plunge cut when the opening was to be large enough. I forgot to ask him what type of jigsaw blades he recommended (he was using Makita cement board blades on the circular saw) but they make tungsten carbide blades that are rated for tile or glass, so I assume that they would work for cement board.

1. 
   user-111832 | Dec 14, 2003 08:15am | #2

   Thanks man. I appreciate your time & info.

2. 
   Remodelboy | Dec 14, 2003 10:26am | #3

   I don't do anything with siding, but I've found that an angle grinder with a small dry cut diamond blade is great for cutouts on Hardibacker 1/4" and 1/2".  I've also used it to cut what I think was a large sheet of Hardiplank - maybe 4'x5', but not siding.  I just lay the Hardibacker on the grass and cut it - it's really fast and helps with the dust.  Good luck!

   RC

3. 
   RW | Dec 14, 2003 10:24pm | #4

   Special blades - the Mak is a good one. The nippers work. They are slower, but clean, and dust isn't an issue. In a bind, the black DeWalt concrete blades ($14) in a skil saw will score it and you can snap the cut, like drywall. But only if you're hiding the cut behind trim pieces. Not in the field. Angle grinder - yup. Never heard of a jigsaw for it.

   "The child is grown / The dream is gone / And I have become / Comfortably numb "      lyrics by Roger Waters

4. 
   Fbart | Dec 14, 2003 10:39pm | #5

   I have used both a saber saw with bi-metal blades ( they loose their teeth quickly, but still cut rather well) and a Rotozip with a tile cutting bit.  This worked OK also. 

1. 
   TrimButcher | Dec 14, 2003 11:25pm | #6

   You can get carbide blades for jigsaws (I've used the bi-metal blades, but they get pretty expensive given they don't last long).  I use a 1/4" carbide bit in a rotozip (1/8" bits work too, but are delicate).

   Regards,

   Tim Ruttan

1. 
   CombatRescue | Dec 14, 2003 11:32pm | #7

   For my siding project, I used a diamond masonry blade with my circular saw.  Works like a charm, but creates a lot of dust. For small cut-outs, I bought some abrasive masonry bits for my jigsaw - they worked great and last a long time.  I drill a hole with, again, a masonry bit to give the jigsaw a place to start.

   I also have a carbide scoring tool that you can run across a couple of times then snap the board at the joint.  A cheap rasp cleans the joint.  This method works good if you can't create a lot of dust.  You can use the carbide tool for cut-outs too, but it takes a long time as you have to keep digging at the material with the tool.

   Hope that helps,

   Andy

1. 
   xMikeSmith | Dec 15, 2003 02:05am | #8

   we've used the Makita cement saw with our Fein auto-vac for about two years now..

   cutouts are carbide blades with our bosch sabersaws..

   we also use the angle grinder for occasional cuts..Mike Smith   Rhode Island : Design / Build / Repair / Restore