How do I drill into lannon stone?

[Dick in Wisconsin]

We have a large Lannon stone fireplace that I've been instructed to attach a 75" TV to. I have a rack a shown in the picture attached with lead concrete anchors (see picture below); TV hangs on the rack. I've been putting the lead anchors in the mortar joints. So far that's worked good for the lower row of slots, but not the top row, mortar joints don't line up. I've thought about moving the frame up or down, but I'm told then the TV isn't properly centered. I have one anchor in a top row slot now and a second one just below the top row of slots; both in mortar joints.


I don't think this is enough on top row. TV is heavy (80 to 90 pounds), most of the stress and weight will be on top. So I'm thinking of drilling into the Lannon stone and using the lead anchors in the Lannon stone where the top row of slots are.

Q #1: Are lead anchors the best anchors to use in Lannon stone (a type of buff-colored, blocky, sedimentary Dolomite (rock) said to be hard)?

Q #2: What's the best way to drill into Lannon stone? I don't have a hammerdrill, although I've read mention that a hammer drill isn't the best for sandstone (which I think Lannon stone is). I'm thinking a regular masonry drill ... slow and steady.

Am I going down the right path? Any suggestions? Thanks!

 

[seber]

Masonry drill should work if you are patient. I use diamond core drills for accurate holes in stone. You can find them very cheap on Amazon. Best used wet but not absolutely necessary. If you go that route, buy more than one. They don't last long when used dry. Especially if you push it. I can't say about anchors. My expertise is lapidary.

 

[LOW1]

Could you use a 1 x 6 (or plywood) so that you could put holes in it that line up with two (or even three) rows of mortar and then attach the bracket to the wood?

 

[slowtwitch73]

Diamond hole saws are the pajamas, but may be tricky to get started.. once you get a uniform cut ring, it's no problem.

 

[Mohawk Dave]

I would try to figure out a way to locate the studs and end up lagging through the rock and into the actual studs. I would not trust that much weight on the rock that is probably adhered with mastic or thinset.

 

[Dick in Wisconsin]

I would try to figure out a way to locate the studs and end up lagging through the rock and into the actual studs. I would not trust that much weight on the rock that is probably adhered with mastic or thinset.

This is a full masonry fireplace. I think there is concrete block or firebrick behind the full dimension Lannon stone.

 

[silkman]

Get or borrow an SDS hammer drill with a 3 or 4 prong drill bit and it will eat that stone like butter.

Here the best is Fischer Duopower plastic fixings, dont know what you have in the US of A...




EDIT: USA site

DuoPower - fischer fixings

The fischer DuoPower is an intelligent 2-component plug with three product functions. The intelligent universal plug is suitable for fixing in all building materials. This allows a variety of applications with just one plug. The fischer DuoPower adjusts itself automatically to the building...

www.fischerfixingsusa.com

 

[tarbellb]

Avoid cracking the stone, use a diamond coated bit to get through to brick.
Lead anchors are my least favorite, I would opt for drop in or even epoxy set.

 

[robert6715]

Does the fireplace get used?

I would be worried about overheating my TV.

 

[The Cobbler]

as above, TV's overtop of in use fireplaces is a bad choice . the heat from fireplace is not good for the electronics

 

[Retroman]

I would drill a good deep hole clean it well and epoxy in some threaded rod mount the bracket and cut off the excess rod.

 

[silkman]

I would drill a good deep hole clean it well and epoxy in some threaded rod mount the bracket and cut off the excess rod.

Dude, no

The replies to the OP tells me you've never heard of plastic fixings and screws in the US of A? Even the lead anchor in the OP is completely wrong for the job (and so 1950s)

These things, probably the first DIY job anyone learns in Europe, are called plastic fixings for when you want to hang something from a wall that is heavier than a picture frame... Drill hole, insert plastic thingy, tighten screw...

4x 8mm fixings (standard, not long) are more than enough to hold a 100kg+ TV bracket and TV onto a brick wall...


Maybe the whole debate is understandable as we don't have houses made of wood either

Sorry, couldnt help myself

 

[mrb1]

Aside from the heat/smoke factor already mentioned, your neck is gonna be sore from looking up. Have a 75" in a room with a fireplace, and the whole object when new was to get it lower. Set was never above fireplace. A short stand and an adjustable stand for the set itself is what we used. Is the top of the set gonna almost touch the ceiling? Ouch.