How to bore smooth hole in blocks.

[SK-Mike]

What tool or bits should I use to make clean smooth hole in foundation blocks.

Need to run a 3/4" water pipe from outside meter to under house (crawlspace foundation). So I'm thinking boring hole 1 inch- 1 1/4" to allow for spray foam insulation around water line.

Do I need a rotary hammer drill? Or a diamond bore saw?

 

[Lassen Forge]

Smooth bore? Diamond hole saw, hands down. Your rotary hammer will work, won't be as smooth as it's breaking through the concrete and rock, the diamond drill is cutting its way through.

 

[ishiboo]

Diamond saw will be cleaner but is a lot pricier. I'd just use a SDS bit.

 

[Rc_Guy]

Diamond saw will be cleaner but is a lot pricier. I'd just use a SDS bit.

X2

That small of a hole at work we would use a hammer drill with a 1/4" bit and woodpecker it, mark the diameter and drill a hole every 1/2" and bust it out. Use some spray foam and a nice wall plate to look good.

 

[ItsNemo]

SDS drill with a properly big bit in it...plenty clean for running pipe through.

 

[850xpeps]

Yup use 1 1/4” sds bit. try locator hole inside and out maybe by using a 1/2” bit first straight through. Then drill in from each side a bit to avoid the concrete Spaulding.

 

[mm08822]

I would use a 3/8" sds/sds max bit and go straight thru the block from one side. Then switch bits to desired size and drill each face from both sides to eliminate any blow out. If it's 3/4 schedule 40, then 1-1/4" bit will give you some clearance.

Know where the webs are in the block before drilling. They can screw up the best of plans.

Clean the holes (water or air) before installing pipe to have a clean surface to seal to.

 

[SK-Mike]

What is an SDS bit? Is that just a regular masonry bit that is used with a hammer drill.

 

[bob15]

It is a rotary hammer (redhead, hilti, milwaukee, etc) drill bit.

The end that attaches to the drill will look like one of these:

 

[marinusdees]

A bit with a splined drive end. Acronym for spline drive system. Originally Bosch. (I think). Requires a spline drive driver-drill. (Not necessarily Bosch).

 

[SK-Mike]

Ok thanks.

Would a diamond core bit require a special drill?

I currently have a 20v max with 5.0 amp hour batteries.

 

[ItsNemo]

A hammer drill will take ages to do anything 3/4" or bigger.

I have a relatively small SDS-plus drill with up to 1" bits that I've used to put 1/2" pipe through 10" foundation walls. Takes only a couple minutes to drill through. The biggest SDS-Max stuff is even more potent.

 

[MJD1]

Claw hammer if it's hollow and your foaming it anyway.

 

[Lelandwelds]

A bit with a splined drive end. Acronym for spline drive system. Originally Bosch. (I think). Requires a spline drive driver-drill. (Not necessarily Bosch).

Spline is different.

A hammer drill will take ages to do anything 3/4" or bigger.

I have a relatively small SDS-plus drill with up to 1" bits that I've used to put 1/2" pipe through 10" foundation walls. Takes only a couple minutes to drill through. The biggest SDS-Max stuff is even more potent.

Not so. The core bits are faster.

 

[Bert_]

What ever you do I would sleeve the line where it passes though the block.

 

[The Cobbler]

don't overthink this project. Block? find the core & drill with 1/4" carbide bit in a circle, knock out the center with a hammer . do both sides and voila! Spray foam if you want & & mortar the hole up for aesthetics. like mentioned above, sleeve it is a good idea, or wrap multiple layers of black electrical tape where it passes thru

 

[DieselNut88]

Rent a hammer drill designed for sds bits and also a coring bit in the size you need. It will make a nice clean hole. It will take more time to set up than it will take to dril the hole. HomeDepot rents them.

 

[MikeF2316]

I'll agree with the folks who recommend the SDS drill. You can rent the drill and suitable bit(s). It does a neat job with minimal effort.

I've never used a hammer drill since my father in law and I put a 2" hole in rock in his backyard for a closeline pole. SDS can put way more energy in to hammering due to its design, which is why the drilling goes so easy. The hole will be neat enough, and since you're using foam it doesn't have to be smooth.

 

[Slednut]

I drilled two 1 inch holes in the footing of my house foundation with a Hilti rotary hammer. They were for 3/4 inch Pex.

Got the drill form work so it was free, was really easy, just let the drill do the work.

BTW I do realize the two holes look like the eyes of a goofy face.