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i need to anchor a 1/2 inch threaded stud to the concrete garage floor for a small pulling device. Have the hole drilled 3/4 inch deep and 9/16 diameter.

Any experts out there on what kind of epoxies to use even if expensive. Needs to hold to at least 500 pounds of pulling. Preferably something available at a good hardware store, Lowes or home depot.

Just a gut feeling with no scientific basis, but only 3/4 deep doesn't sound like a lot of surface area to hold 500#. And just a threaded rod, no "T" or similar at the base to form some sort of mechanical lock? I'd just guess you want a depth more like 6 or 8 inches at the least, maybe more.

When the tunnel roof fell down in Boston's Big Dig, several of the articles on that failure noted the name of the epoxy supplier used to hold the concrete roof panels in place. You might get a manufacturer's name that way and then follow up with their recommendations.

In electrical work we use drop in anchors which can be very strong. You can get them in 1/2" threaded size. You need to use a set, which is a long blunt tool you hit with a large hammer to force the bottom of the anchor to expand. The hole needs to be drilled to the manufacturers' specifications. If installed correctly it has a pull out strength of 6000 lbs.


http://www.confast.com/products/technical-info/drop-in-anchor.aspx

Agree with O-D and carlmadsen. 3/4 is not deep enough and doubt you can find 1/2 inch anchor that shallow. Epoxy very questionable at that depth, but there are sets consisting of a rod and special metallic reinforced epoxy in a glass vial which the rod breaks and mixes--but needs much deeper hole and industrial supply house to buy in quantity. Doubt anything in hardware store strong enough long term. A deeper hole which was larger at bottom and some hydraulic type expanding cement MIGHT work--if the rod were also keyed in some way besides the threads..

Think anchors would be better & tool is very important to properly set the anchors wedge depth and expand the end without damaging the threads. Just be sure the hole not oversize with anchors.

The two drop ins I show are available in various brands at hardware stores mentioned (and also Orchard Hardware if you have those in your area) & each require at least a 2" deep hole. (The long threaded type, even deeper--but that one maybe not applicable for your need unless you use a coupling bolt.) Those are the preferred type most structural engineers specify here for seismic sensitive since the harder the pull, tighter the grip assuming hole is correct and concrete is sound.

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I have to ask, what is "wquipment"???

Eric, Go to MS Word and type
"I well niver mace a misteak un Packardinfoo" 500 times and send it to Big Kev to be kept in reserve.

Randy, LMAO! You know me, I gotta be the jokester!

Just a follow-up:

Yeah, 3/4 inch deep. WHAT was i thinking???? I went ahead and bought a 1/2 inch drill bit (the only masonary size i didn't have) for $4.00. Drilled the hole about 2-3/4 inches deep. Drove in a stud like the one on the left most side of HH56's pic. But my stud was only threaded at the top 1.5 inches. The shank into the concrete is only 2-5/8 inches long. Total length of stud 4-1/8 inch long.

I'm glad i went ahead and splurged for the drill bit. When HH56 showed the pic above it reminded me that i already had a coffee can full of those kind i had forgotten about.

Thanks Owen, HH, Carl and everyone

BTW, standard residential concrete slab is no less than 4our inches.