Aside from safety gear, any special tips with using one of these? I'll be renting the roto hammer.

I'll be drilling holes in 2'x2'x6" pads for a pad/post cabin setup to secure RR ties to them. I know I'll need some masonry epoxy to hold my anchors in place; anything else to consider?

I'll be using bits for cutting rebar, as the pads will already have reinforcement in them.

Are the pads already poured? If not, how about setting anchor bolts? If you provide the concrete guy with templates and some kind of setting plan it might be easier. Make sure you buy a good epoxy, like Hilti, and don't drill your holes too large. Depending on the bolt size you are limited on the hole diameter. Just my $.02.

Carlos

I'm in the tool repair business. What size bit are you going to be using and what model of hammer drill is it you are renting along with what is the amp draw. Reason I ask is everybody will use a million miles of extension cord of too small of a gauge and they will totally and I'm mean totally burn out the tool. At a draw of 15 amp and assuming that your voltage is clean (110-115v) you will need a 10 gauge cord at a max length of 25 feet. If you don't follow this you will be buying yourself a burnt out hammer drill from the rental shop with holes still left to drill. A sharp bit is also essential.

I forgot to mention, hit rebar with a carbide bit = go to hardware store to buy a new bit.

I'd use a rotary hammer drill and wedge anchors instead of drilled holes and epoxy. I've seen some literature on epoxy failures in cold climates. Wedge anchors from Simpson are my choice. I use 10" long .5" diameter anchors. Drill an half inch hole, drop in the anchor, smack with hammer to set the wedge, and tighten the nut. 7" imbedment is recommended, which means you'll have to countersink the nuts in the rr ties. PM me if you need more. I rotohammer about once a week on something, since I do LOTS of concrete construction.

Cutting the rebar with a rotohammer bit is the pits. Try to avoid the rebar mat if possible. How deep is your frost line?

Gloves and long sleeves and a full face shield are nice, but a roto hammer does not throw a lot of eye eaters. Mostly dust. Like concrete buggers?

I'd have to agree with Fasteddy. In cold weather I've also heard that epoxy anchor are a little sketchy. I would also recomend wedge anchors. I think they are easier to work with as well.

California requires epoxy.

No big deal, just use eye protestion and a good carbide. Blow out the holes real well and use epoxy. They also make epoxy capsules you pu tin the holes and they break when you tap the rebar into the hole. <img src="/forums/images/graemlins/cheers.gif" alt="" />

The pads are precast; I did the math on doing a pour, to include borrowing a friend's cement mixer, and I'm ahead about $600 (you read that right)to go into town and pick 'em up and yank 'em off on my end with a Bobcat. I'm 47 miles from the nearest cement truck, so you can bet I'm not calling them unless it's for a monolithic pour.

Eddy, this is called pad and post construction. The hole is backfilled 4 feet, and compacted to 1 ft above grade. Our frost line here is 6 ft; without snow it's more like 8 ft. <img src="/forums/images/graemlins/zombie.gif" alt="" /> A lot of Lower 48 construction goes by the wayside up here.

After the pads/ties are cinched together, my other hardware will be set up for leveling from time to time. I don't hit gravel in this particular spot until 8 ft. That's a LOT of dirt work for only a 28 x 36 pad.

Am leaning towards wedge anchors; with the RR ties, I'll be using threaded rod to double-nut them in. Thanks for the countersink part; was considering that too. I'm working with 5/8" stock, as we've got a seismic consideration for this. I'll have to ask the industrial hardware guys for sure about my anchor choice before I go layin' out coin. Spent one day running around lining up hardware last week.

I've got dust masks and eye gear. <img src="/forums/images/graemlins/kewl.gif" alt="" /> Am debating about gel gloves, but it's a comparatively small job. Bits will be new; hopefully the next project comes in the form of a GARAGE.

Thanks also for the extension cord tip. IIRC, most of what these guys have are Hilti roto hammers. I was looking for amperage on them, but only found the wattage rating. Will be running off a generator on site to smack this stuff together. Mini shop vac will also be on site for cleaning the holes. Guess I'll stop by again and look at my two choice models and google them for specs to see what I need to use.

Thanks guys! <img src="/forums/images/graemlins/cheers.gif" alt="" />

Volts x amps = watts, or
Amps = watts/volts, if I remember my high school algebra.

Thats right
Russ <img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/cheers.gif" alt="" /> <img src="/forums/images/graemlins/patriot.gif" alt="" />