core drill for cement

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Can  anybody tell me anything about boring 4" holes in concrete. I have a bid for pool fence to do the pool has cool deck all around it. The client want the fence in the deck not nect to the deck. I've never seen it done before. I don't know if I should sub it out, rent a tool or buy a core drill bit for one of my drill motors.thanks Tp
Reply:Find Out If It Is True Cool Decking And How Long Ago It Was Done.  The Older Product Had Asbestos In It.  So Take The Necessary Precautions.
Reply:You can rent the rig and rent the bits. Some charge for the wear on the bits. It's not a difficult job but generally works best if you just sub it out. Just like anything you can probably do it yourself but the guys that do it every day can do it a little quicker and better. Renting isn't always cheaper by the time you figure in going to get the stuff and taking it back, unless you work for nothing. Go to pick it up at 7:30 in the AM and it didn't come back from the previous rental, second trip later in the day, bla bla bla. Generally one of the varieties of diamond impregnated and/or carbide toothed core bit. Used with water for lubrication. Small holes get drilled for anchoring the drill motor. If you want to get prices just call a major rental and tell them you want to core drill some 4" inch holes in a pool slab. They'll either know what you're talking about or won't real quick.
Reply:Tp, I am in the concrete biz and I sub stuff like that out. The bits and rigs are expensive to buy and rentals are usually barely passable. It is just easier to have guys that do that kind of stuff all the time to do it. It will get done faster and easier. The quality of equipment makes a huge difference in speed as well. For example...one of the things I do is concrete cutting. I got fed up with all the puny rental saws and bought me a 500#, 20hp beast of a saw that made extermely short work of my jobs. The rental saws would cut a typical job in 6 hours or so...and that was pushing hard. My new saw would do the same job in about an hour and a half without all the effort either. The price difference between the two saws is nearly three grand...and you absolutely do get what you pay for. Same applies to core rigs. The rentals are El Cheapos and don't work very good. The pros will have the super primo rigs and bits. They would make short work of the job and do it cheaper than  you could. Now if you only have a few holes, it may be just as easy to do it yourself......then maybe not. Give a concrete coring company a call and see what they can do for you. FWIW, You need a pretty big drill to run a 4" bit.....don't do it with your handheld drill. You will either kill the drill or yourself when it binds up...but you will definitely kill the bit. The core bits I used to get ran about 500 for the cheap ones.
Reply:I cant comment, specially now that Don has been sumoned.  However, I shall still steel the stage for a moment for STory time.I was an appreciate on a pipe job.  I got for a couple weeks the task of catching the cores for the core driller.  He would drill cores, dont remember size but like 4 or so I think.  I would catch em in a bucket.  This got wet and nasty.   Most fun was there was four in one lil "closet."  it was maybe 6 feet by 7 feet and in a diamond shape with walls on all sides except there was a lil hole in the rock for me to get in there.   like a slit all the way up it and it was just wide enough to fit.  Well core man said,   get your ladder in there and stay off tothe side.  When these cores drop youll be ok but they will skid all over the floor and bounce around.  Stay few steps min on the ladder.  Dont need to catch em thogh.Well each time theyd fall, they would zip around that lil room.  One finally busted throgh the rock, went into anutter room, and busted a glass pipe!  Well I immediately had to go tell my foreman.  I show up and the super is standing there.  Willie says what you want boy you suppose to be catchin cores.  I said, I gotta prob Willie.  Stephen the super said what is it?  I told him.  He said you werent catching it.  I said no and heres why.  He said hmm I gotta see this.  It was only second or third core.  So he sees it.  Said, well you know I appreciate you telling me.  Ill get another crew to fix it, but lets watch the rest.  So we found a piece of board to cover the hole, and then we watched the core guy core out the rest of  them holes.  After that Stephen would call me down to the HQ just to shoot the sh*t.  I really enjoyed working for him.   He appreciated my upfrontness and honesty and that I wasnt afraid to talk to him.  He got there and after introducing himself as the new super, he was told he was the new headhunter the whole jobsite had been warned about.  He was not impressed.  Nobody would talk to him, fearing their job.  I never cared.  I figured if I was let go Id be to work the next day lol.   There are benefits to living in Dallas, you know Don IF it Catches...Let it Burn
Reply:I've done quite abit of coring in bridge decks and concrete dock panels.  I'm not really sure what cool decking is.  A regular drill motor will not work in my opinion because the bit can't have any wobble or it will knock the diamond cutters off the core bit. It also needs water flowing down the inside of the bit to flush the dust out of the cut. If you don't flush it out the bit will bind and burn up in just a few minutes. Also the water keeps the dust down if it does have asbestos in it. If I were you I'd check into renting a core machine and bit. I can't imagine there's a lot of rebar in cool decking as sometimes that can be a problem. I've also had to core right down the middle of nelson studs. That can be a pain also. Another thing you have to do is anchor the core machine down. If the deck is smooth most machines come with a suction base to attach it. It will have a vac pump to create the vacuum. If not you might have to drill in an anchor bolt to anchor it down. This might not go over well with the owner. We have a piece of steel that is 4' by 6' by 2" thick that we welded bolts on to anchor our machines. we move it with a forklift or crane. The  cool thing about this is when your coring rows of holes to pur concrete though the deck 2 guys can core 4 holes at a time. I usually figure around 10 to 15 minutes per hole in a 6" deck. I don't know how many holes you have to core. Depending on wages paid out or time it might be better to sub it out. It not hard to do though.Last edited by spuddown; 05-02-2006 at 01:42 AM.
Reply:Yup, there are indeed. Kinda like here, too. Always something going on somewhere.I have always hated the slurry from wet cutting. Slimy , nasty....nope me no likee.  Might be why I always try to dry cut.
Reply:This machine was pretty sweet.  Tom, it had a set of wheels.  It ran relativly slow but cut pretty quick.  Dont remeber how the water was held, but it definately worked with water as Don mentionedIF it Catches...Let it Burn
Reply:well thats pretty much what i needed to know, thanks guys
Reply:Tp, I don't know if they are still there, but Concrete Renovations used to have a Dallas office. They are the ones I used to use for my big stuff. I now use another co.......don't remember why I switched. May be  due to the fact the new one will do curb cuts and Reno doesn't...been too long.
Reply:Hire it out man- A decent core drill can run several grand, easy. And every rental place I have ever been to SELLS you the bits- maybe somebody rents em, but not around here. I pay about 50 bucks a hole for core drilling, and I consider that a bargain. The guy comes out with 5 grand or so worth of equipment, and he worries about the bits, not me. I make sharpie marks on the concrete, and the hole is right where I want it, as deep as I tell him.Price it into your bid, and pass it along, plus 10% for your time, of course.
Reply:I've been in the pool business for 25 years.  Since i'm in bfe, i usually have to depend on myself.  Even here i can rent a core drill, save time and money and have more money in my pocket.  Although i have seen big bits for a "macho drill" it is better to rent one that has a hole saw type of bit and is cooled/lubricated with h2o.  Most place even have them with a vaccuum machine that anchors the drill to the deck.  They work much like a drill press.Go slow to stay strait.  Also you will have minutes shaving of rerod that will leave rust spots almost immediatly if you don't take precautions.  I learned the hard way on the white stairs of my own pool.  Also watch for this if you suv the job, because the home owner will hold you responsibel.  I hope this was helpful.
Reply:Ive seen folks using hole hawgs before get pretty messed up from em.  One guy I worked with was using a rather large, I think a 4 inch hole hawg.  He was cutting thorugh a wall and hit something and the backlash on that very large and powerful drill motor broke his wrist.  Remdinded me of the handcranks on old tractors reaslly.  Theres a lot of torque and power, these units arent conventional drill motors, they are stand up units that work more like a drill press in  a sense.  Like the otehrs are saying, outsourcing is best way to handle.IF it Catches...Let it Burn
Reply:Ive seen folks using hole hawgs before get pretty messed up from em.
Reply:hey ccrane you'd do that before you'd mount a 4" plate and weld the post to it?Thats what I decided to do but it sounds like I'd be better off boring the holes.If your using 2" sq tube for post you would do a 4" hole right? How long does one typically take? Where is BFE?
Reply:TPnTX:BFE= Bum F*** Egypt.I once built a radio tower in Royse City, Texas.  It was out in the middle of a sorghum field in late July.  Hottest job site I every worked on... except for the time that I ran conduit in the attic of a dry cleaners in August...
Reply:[BFE= Bum F*** Egypt]lol "no sheet shirlock"
Reply:if you can rent a good drill with a good bit, usuallly 4 to 8 minutes a hole.  dedpends on  how much rerod you hit.  then use hydraulic cement to mount your posts
Reply:Thats what I decided to do but it sounds like I'd be better off boring the holes.If your using 2" sq tube for post you would do a 4" hole right? How long does one typically take?
Reply:thanks Tap, even though I've gone back and forth on this I keep comming back to the plates. What I'm calling cool deck is some kind of cement deck which has a surface texture to it and is white-ish. I don't know how it works but it doesn' get as hot as regular concrete deck.As a matter of fact the quote I gave the client was to use plates but I noticed that it's on grade around the edges and isn't very uniform. I can compensate for that.Anyway thanks for the help everyone.TpLast edited by TPnTX; 05-10-2006 at 06:27 AM.
Reply:I prefer to core drill in the application you describe. But when I must use bolted bottom plates, especially around water or chemical,  (pool, walks with ice melt used, etc.) I go the extra and use stainless steel. Buy 3" or 4" SS  flat bar, drill or punch holes, cut to length, weld to uprights. There will NEVER be rust bleeding, anything that needs paint touch up is accessible. If you go this far, be sure to use ss anchor bolts. This will cost more for plates and hardware, ( I just factor the extra cost in), BUT the job will look good for about forever! This is also something I do on wood or fake wood decks.Just my  opinion, not from a book, just from the road.Howes Welding Inc.www.howesweldinginc.com