Core sawing

[Billct2]

I have a single side 4x8 sign to install on top of a concrete wall that is capped with bluestone. I want to sink 2"x2" square aluminum tubes for support behind it.
Never used a core saw, but can rent one from the local tool place. Just wondering if anyone has any experience/tips. For instance is it best to make the hole as small as possible?
What to use for securing the posts, hydraulic cement? (and before anyone says... "How can you sell a job before you know how to do it"- the install is time & materials)

 

[Gino]

If you mean a core drill, for larger holes, they have a pilot bit inside the actual core bit. Just go slow.

 

[Johnny Best]

Fast Plug, cement, from Home Depot. Works good.
And yes, keep the hole as small as possible, looks better than an oversized hole.

 

[netsol]

we have a weka drill, if that is what you mean

https://www.amazon.com/Diamond-Products-Core-Cut-47055/dp/B00548DJB0/ref=sr_1_2?crid=2HT0NG5R7E92O&keywords=weka+drill&qid=1682719733&sprefix=weka+drill%2Caps%2C255&sr=8-2

great piece of equipment. you can cool the bit with water or compressed air

 

[Moze]

I have a single side 4x8 sign to install on top of a concrete wall that is capped with bluestone. I want to sink 2"x2" square aluminum tubes for support behind it.
Never used a core saw, but can rent one from the local tool place. Just wondering if anyone has any experience/tips. For instance is it best to make the hole as small as possible?
What to use for securing the posts, hydraulic cement? (and before anyone says... "How can you sell a job before you know how to do it"- the install is time & materials)

There are obviously other factors, but the general rule of thumb for proper support is the hole diameter should be 3 times the pole/post/tube diameter (2" tube = 6" diameter hole) and the length of tube below ground should be equal to 1/3 of the length above ground.

That being said, if you're coring into existing masonry, it depends on how much of the post is going to be in the masonry, the dimensions of that masonry structure, etc.

I'm a bit confused about sinking tubes "behind it". Got a pic of the wall? Drawing of plans?

 

[Billct2]

I meant the posts would be behind the sign, not showing.

 

[GB2]

You could have a plate on the bottom of the post and then all you would need to do is drill small holes to anchor the plate. You know, this is typically how larger steel posts are anchored on footings, with J bolt anchors that are embedded in the concrete. For your installation you can just use an appropriate masonry anchor or drill the hole and use epoxy to set some threaded rod.