Drilling holes in concrete?

[widebody911]

I need to drill 2 (maybe 4) holes in concrete and install some nuts so that I can bolt and unbolt stuff. The bolts will probably be 1/2"

What's the best way to accomplish this? What's the best fastener to use that's easy to install and remove?

[vash]

wow, that is kinda big. our contractors do this all the time. if there is repeated bolting and unbolting, they epoxy in threaded fittings. you will need one of those big, cool bosch hammer drills.

if you are going to leave it, they use this bolt that looks like a big sheet metal screw. just predrill and rattle it in. doesnt do that great once you take them out.

[greglepore]

A good hammer drill is the tool of choice, with the appropriate bit-Hilti is one of the best.

I'd probably epoxy the nuts in place - there are structural epoxys for this sort of thing.

I'm assuming this is to tie down molds or something rather than pulling w/ a portapower or like, as you need serious anchors set in the crete for that sort of thing.

[Jims5543]

What is the "stuff" that will be bolted and unbolted?

[widebody911]

I bought a tubing bender, and need a way to mount it. I don't want it to be permanent, but it has to be reasonably strong while I'm using it.

I pulled the 1/2" size out of my cloaca; I don't think they have to be that big, but that would definitely be strong enough.

[Porsche-O-Phile]

Floor/garage type slab or something structural? If structural, you need to be careful to not hit any rebar. . .

[masraum]

Originally posted by widebody911
I pulled the 1/2" size out of my cloaca

Primarily reptiles, amphibians, and birds have cloacas. I'm sure if we asked some of the ladies that you've dated they'd say you were a snake, but....

[Jims5543]

I would try the epoxy thing first. If you will be applying a lot of leverage to it I woul dthink you might have to do something stronger.

[juanbenae]

you can rent a hammer drill from most rental places. if this is the concrete slab you poured with-in the last couple years you may be able to get away with just getting one of those concrete drill bits that go on a regular drill. if you decide to use one of those i would use a garden sprayer and water, or the like to cool the bit while drilling. if not you will cook one of those bits before you finish the hole. expoxy and all-thread are good, or you can use a "redhead" type expansion bolt.

whatever you use can be cut off flush with the concrete (with a sawzall) should you eveer want to move the thing, or you sell the property.

[lendaddy]

Toby gots it (though you need not worry about water for a couple holes). I've done hundreds of these things to secure equip in our factory, it's simple and they work. Hammer em home

[widebody911]

Originally posted by k911sc
expoxy and all-thread are good, or you can use a "redhead" type expansion bolt.

Sounds good, except I will need to use a female fastener, so I don't have something sticking out to trip on when I'm not using it

[Burnin' oil]

Originally posted by widebody911
Sounds good, except I will need to use a female fastener, so I don't have something sticking out to trip on when I'm not using it

If I was Thom, I would have a witty reply to that.

[dhoward]

Thom's not the only one tripping on his ***** around here....

[Jared at Pelican Parts]

I just did 3/4" holes in a slab for securing a electric gate motor down. Rented a Milwaukee hammer drill from Home Depot and had it back in a couple hours. I used anchor bolts to secure it. Just hammer them into the slab. Holds a 150lb gate motor with a chain driven 3000lb load just fine.

[vash]

yea but that isnt removable.

thom just use that two part epoxy and glue down some threaded couplers into some drilled holes. then you can counter sink them a bit, to leave a bolt in them even if the tool isnt connected. keep the dirt out. the downside is that you will have to drill a big hole to accomodate a .5 inch bolt. hammer drill time. it will cut like butta.

[svandamme]

Hilti's rule when drilling in concrete



no need for water cooling the bit or what not
those buggers cut through like a hot knife through butter

[EdT82SC]

I bought this one from Sears for $60 on sale. Cut through cinderblock like butter.

http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00910116000&subcat=Drills

[elwood-914]

Use a drop-in anchor, you have to drill the same depth hole as the anchor (so it sets flush) and you need a setting tool. You pound the setting tool with a hammer to expand the anchor.....there you have a female insert for bolts that is flush with the floor. I have used 1/4", 3/8" and 1/2"

[Tobra]

rent a hammer drill

[TerryH]

Originally posted by elwood-914
Use a drop-in anchor, you have to drill the same depth hole as the anchor (so it sets flush) and you need a setting tool. You pound the setting tool with a hammer to expand the anchor.....there you have a female insert for bolts that is flush with the floor. I have used 1/4", 3/8" and 1/2"

I agree with Elwood here....

This is what you need to have female threads for anchoring your bender. I've installed these about 1000 times when I had a real job. You can pick any thread size you want.

http://www.confast.com/products/drop-in-anchor.asp