OK I have a tricky situation. I have to install quite a few recessed lights. Most of them I have accessed (ceiling down), some of them I do not. Of the ones I do not, some of them I need to drill large holes to mount them, and some of them have existing non-functioning recessed lights already in place I need to remove first. I intend to use as much as I can get away with IC housings for new work (not remodel) which means I need to get adequate access to the space above. The ones I already have 35 year old beat up non-functioning rusted housing up there, with the flanges attached to the joists, and I need to attach a new one (different diameter) I will have to figure out a way to remove them, and attach new ones. To make the matter more complicated, the ceiling is not regular sheetrock, but a 3/4" thick material which is composed of 3/8" of plaster on top of 3/8" of gypsum board backing so cutting must involve a carbide blade. I do have access to one of these: and can cut a large hole up to 9" in diameter. I think my best bet may be (I already disconnected the wirings) use a hammer to knock the existing can back into the attic, then insert a piece of 1x2 wood into the hole, and secure the wood to the drywall across the middle from the inside using a few screws, then use this shielded hole cutter with the starter screw going into the piece of wood in the center and cut a 9" big hole. I tested this with a piece of scrap wall I demolished, and it cut through it like butter and no dust. That would allow me enough room to cut out the existing housing and flanges, and probably enough room (I hope) to mount a new housing to the joists. The advantage is I can easily cut an identical piece of 9" hole and the patch would be perfect, and if I do that for all the holes I do not have access (about 16 of them), the patching work would be the same and no need to waste time measuring each hole being cut slightly different sizes etc... One other upside is that this hole cutter has a plastic see-thru shield that collects the dust. Using a rotozip angled up even wearing eyegear there is no way to stop the nasty plaster dust from getting into your eyes and nose. The downside is I would be patching a round hole, which I have not done before, how would you apply straight drywall tape to a round hole? Do you use short strips? The other downside is in the event a 9" hole is not enough for me to mount the new housing, I would have to further enlarge the hole until I can...there is no going back to using remodel housing since the drywall support from a patch would be inadequate. Any thoughts or comments or alternatives? Thanks, MC

Hi All, I've got an army of cracks in my 80+ year old plaster that are just begging to be dug out and repaired but I can't seem to find any Durabond for sale in my area. I checked the 2 Home Despots :D near me as well as a Lowes and couldn't find any setting JC's. I did a little searching on google maps but couldn't come up with any plaster / drywall supply places either. Anybody know of somewhere in the area that stocks it? I should find it with the other plaster / JC supplies, right? Thanks.