Mounting Gemini letters on granite

[michsanford]

Any suggestions on drilling into a granite wall to mount Gemini letters? We need a 3/16 hole, but about 200 of them.

Thanks!

 

[Billct2]

What kind of granite wall, interior , exterior, smooth, rough...what material letters, how big?

 

[michsanford]

It's an exterior wall, rough surface.

they are plastic formed letters, varying in size around 18"

 

[J Hill Designs]

SDS+ hammer drill

 

[Billct2]

Yep, I agree. Careful not to crack it.....

 

[Moze]

I third that. SDS rotary hammer. NOT a hammer drill. If you don't have an SDS, now's the time to invest in one.

 

[BobCap]

Drill 200 holes...it'll take you a month. I hope you are charging enough...

I would use 3M VHB tape. If it's good enough to hold trim on your car...

Or some other kind of adhesive.

Bob Cap
AAI
Gilbert N

 

[Mosh]

VHB or Silicone. No way I would drill into that, too much risk of cracking it.

 

[Jester1167]

SDS+ hammer drill

Sometimes it is more accurate to start with a smaller bit on textured walls. The larger bits tend to walk more when starting the holes. Also bring a larger" bit for the few misaligned holes that won't allow the letter to sit flush.

If you have a leaf blower, bring it. They work good for blowing off the wall and the holes out before installing the letters.

 

[TammieH]

I third that. SDS rotary hammer. NOT a hammer drill. If you don't have an SDS, now's the time to invest in one.

or rent one for around $20 a day, more or less depending where you live

 

[letterman7]

Ok, I'll ask: what's the difference between the DeWalt SDS and the "regular" DeWalt "hammer drill"? They look nearly identical to me except for the switch on the side of the SDS (of course, I have an ancient hammer drill here).

 

[Moze]

Drill 200 holes...it'll take you a month. I hope you are charging enough...

I would use 3M VHB tape. If it's good enough to hold trim on your car...

Or some other kind of adhesive.

Bob Cap
AAI
Gilbert N

It'll take about 2 hours.

How exactly would you go about mounting a (edit: an 18") formed plastic letter with VHB and silicone?

 

[Moze]

Ok, I'll ask: what's the difference between the DeWalt SDS and the "regular" DeWalt "hammer drill"? They look nearly identical to me except for the switch on the side of the SDS (of course, I have an ancient hammer drill here).

An SDS rotary hammer delivers a lot more impact energy than a hammer drill.

 

[Jester1167]

I wouldn't think he would need to worry about chips, the wall is textured and the strokes on the 18" letters will cover up any small chips.

 

[Billct2]

That's why I asked for deatils, if it was aion interior wall, flat & polished I'd do VHB & silicone. Exterior flat, maybe a short stud with pad/silicone. Exterior roughgranite you gotta drill baby drill. And I agree it's a good idea start with a pilot hole.

 

[letterman7]

An SDS rotary hammer delivers a lot more impact energy than a hammer drill.

Ah, ok, thanks for that. I would think that an SDS would have more chance of cracking the granite than a standard hammer drill, no?

 

[J Hill Designs]

Id say no. SDS+ will eat through granite like butter

 

[Moze]

Granite doesn't tend to crack. It WILL break out on the back when the bit punches through if the granite isn't adhered to a backer, but since this is an outside wall, that shouldn't be an issue.

42 holes, no cracks, just break-out. Skip to 4:50 to see what it does to the back.

[video=youtube;HhBdm3WeUC4]https://www.youtube.com/watch?v=HhBdm3WeUC4[/video]