Drilling 1" holes through concrete/racking system for metals

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Not welding related at all, but I am putting up a rack to hold my steel which I will be welding, so I guess in a far stretch, it is welding related! But I have a hollow block wall that I am installing a rack to hold my metals. Rack itself will consist of 3 sections, 84" tall 36" wide with 5 arms on each end stretching out 24" with a diagonal support under the arms. Get the picture? The bottom will also have arms (more like feet) to help with supporting the weight to the concrete floor and not all on the wall. There will be tabs welded to the top corners of each section. Each tab has 2 holes so a total of 12 holes for the 3 sections. I plan to use 3/8" togglers/wing anchors, or whatever you want to call them. Material is 1-1/2" x 11ga. Simulated in Autodesk Inventor's stress analysis, 750lbs loaded on the END of the arms of ONE section gives me a 2.0 factor of safety (also accounting for 30% shock load). Most of the items that will be stored will be 3' to 10' lengths, though there will be one shelf to store 15' to 24' lengths that can slide right onto the cold saw roller table, but these lengths will be supported by all 3 sections. The Togglers I have call out for a 1" hole. The block is about 3/4" to 1" thick until I reach the hollow section.If any of this doesn't sound right, or just outright dangerous please let me know! Also please let me know if you have any recommendations, considerations, or design changes. But my real question is what is the best way to drill the holes? I do not have a large hammer drill, just a drill with "hammer mode". I have a couple of carbide tipped hole saws for use in masonry, but I have a feeling their purpose is more so for tile and not sure how they'd hold up to thicker concrete drilling. Anyone have any luck with these or other methods of cutting holes through concrete? Haven't looked around too much, but I've also seen some diamond grit hole saws, etc.John 3:16(2) Miller Pheonix 456(2) Millermertic 252Dynasty 210DXHobart 210MVPDoringer D350 SA Cold SawScotchman 350LT Cold SawWebb 10x50 MillWebb 15x40 LatheGeka Bendicrop Ironworker
Reply:I'm no engineer. How far will the ends of the racks be from the ends of the wall? IMO I'd put some anchors in the uprights halfway up to help support the horizontal load on the wall. Block walls aren't fond of horizontal loads. Maybe even drill all the way thru and have bolts going thru some sq tube about 3' long to spread the load.                                             MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:I'd very cautious about taking a hammer drill or rotary impact to a hollow block wall. That block is going to want to 'pot' out on the back side even with a conventional masonry bit."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:You might find this of use.https://www.us.hilti.com/medias/sys_...05_APC_RAW.pdfWe almost never use wing toggles in hollow block. If it needs to hold any weight, it's almost always Hilti epoxy anchors and hollow block sleeves. You'll find your basic condition shown in Figure11 near the end of that PDF. They show the 2 part Hilti epoxy in that guide, but Hilti also sells the 2 part epoxy in tubes that fit standard  caulk guns and in capsules so you don't need specialized tools to do the installation. Home Depot used to stock the Hilti adhesives, but they don't any longer at my location. There are other companies out there selling similar products though. I forget what Depot/Lowes sells right now, but I remember seeing something other than the Hilti stuff at one of those stores recently.For years we've dealt directly with the Hilti store. I've set a lot of their epoxy anchors. In solid block it's important that the holes are clean. Usually a blow gun and bottle brush will clean holes well enough for good a grip. I used epoxy anchors to set all the top plates on the block walls at a house down at the shore before Sandy. Didn't have any issues with up lift in the high winds from the storm. We've also used these to set anchor bolts to hold down structural columns in several buildings, all approved by the engineer for that use.Big advantage in your case will be that it will allow you to use a lot smaller holes to set the anchors. 3/8" or 1/2" holes will probably do for what you need. 5/8" at most. All are easily drilled with standard masonry bits. I'm not a big fan of giant holes in block with hammer drills. I have bits for mine that go up to almost 2" ( biggest will take a standard 1 1/2" PVC pipe for sump pumps). It's real easy to have the block blow out, especially if the block is old and weak. that's no big deal when we plan to patch the holes with hydraulic cement for pipes anyways, but a disaster if you intend them for structural use. I've used diamond bits to bore holes, but usually in larger sized on solid concrete. Cost of the bits is usually prohibitive and the drills are quite heavy as well as expensive. They can be rented at most rental stores however..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Good advice so far.  Yes the holes will tend to blow out drilling into hollow block.  As you get close to the back side with your drill bit reduce pressure and you can minimize blowout.  Good advice on drilling all the way through and sandwiching the wall with support on the back.  You might be better suited to make the rack freestanding and not jeopardize the structural integrity of your wall.
Reply:if you can- drill completely through the block wall and use fish plates on the far side with threaded rod. the plates will also cover the divot the drill makes as it breaks through.i.u.o.e. # 15queens, ny and sunny fla
Reply:We use double expansion anchors that work well. It sounds like the rack will be self supporting on floor and against block wall. What is above the rack ? Bar joist ? Steel beam ?If so you may add some steel to rack to tack to ceiling steel if there is some. Through bolting is best if you are really concerned as mentioned. We have done this for heavy suspended loads. 4'' channel with holes and 3/4 all thread through wall and another 4'' channel with bracket welded to pipe support. Wall is sandwich between channels as said above. Here's a double expansion anchor, https://www.fastenal.com/web/products/details/51143I'm North of Chicago near Gurnee Mills six flags. I have the drill and bits if you want to come North for your use. I might have enough 3/4'' rod too depending on how many feet you need. PM me if this will help.
Reply:Unfortunately the other half of the wall belongs to the neighboring unit, and I don't think they would like holes and plates/bars in their office. Also, the ceiling is close to 20' and it's a drywall ceiling. Kind of a weird shop building, it's got vaulted celings.  Originally Posted by BD1We use double expansion anchors that work well. It sounds like the rack will be self supporting on floor and against block wall. What is above the rack ? Bar joist ? Steel beam ?If so you may add some steel to rack to tack to ceiling steel if there is some. Through bolting is best if you are really concerned as mentioned. We have done this for heavy suspended loads. 4'' channel with holes and 3/4 all thread through wall and another 4'' channel with bracket welded to pipe support. Wall is sandwich between channels as said above. Here's a double expansion anchor, https://www.fastenal.com/web/products/details/51143I'm North of Chicago near Gurnee Mills six flags. I have the drill and bits if you want to come North for your use. I might have enough 3/4'' rod too depending on how many feet you need. PM me if this will help.
Reply:A couple things to consider. Some masonry construction has rebar in the walls depending on code and specs. The rebar is solid with mortar surrounding it. The other is depending on how much mortar is on the mortar board at break, lunch, or quitting time , it ends up in the wall somewhere. For these reasons I drill a pilot hole to determine what is inside  the hole location. If the block is solid, then drill the  hole larger  for a double expansion anchor and if hollow use the toggle wing. As for the larger hole, by using the hammer drill on '' DRILL ONLY '' you may prevent the inside from blowing out. If your holes could be laid out near the edge or rib of the block helps too.
Reply:A free standing shelving unit would be better.  Unequal legs, longer in front to make it lean back against the wall.  Or shims to do the same.To attach anything to a hollow wall you're better off using construction adhesive to a glue a nailer (2x4) to the wall, then screw the rack to the nailer.  Adhesive will work if you wedge the nailers against the wall during the cure time.  You'd be amazed at how much holding power a full height nailer (84") will have when using construction adhesive."Any day above ground is a good day"http://www.farmersamm.com/
Reply:Use a smaller expansion anchor and place them in the mortar joint.
Reply:Econdron,Like Roadhunter has already mentioned what about going free standing and leaving the block wall out of the equation.   Especially if you're just renting the space it would seem to me to be the way to go.   I built three separate upright sections like you've talked about doing and then just connected them together top and bottom with a horizontal piece of 2 x 1/8 wall square tube.   I've had a lot more material in this rack than what you see in the picture and haven't had any problems with it.
Reply:HT2, that's almost exactly what I have in mind in terms of racking. The rack itself will be free standing. I just want it anchored to the wall as well so the upright doesn't start tilting forward as weight is loaded, and the extra rigidity is desired. Now that I'm thinking about it, I could probably just use some LDT's. And I own the unit, I'm not renting. I want to build to build this unit so that it can safely hold up to the most that I may want to load on it. I want to be able to take the steel right off the delivery truck and load it on the shelving so it's right there for when someone gets to that project. Right now I have about 50 lengths of 20'-24' long pieces of tubing, flats, angles, etc all for one project. Like I said, it would be awesome to be able to load that all on the one shelf that feeds right into the cold saw. Based on my calculations, this is about 2,000# of steel, which the arms themselves should be able to support, I'm just not sure how much flex I'll get on those uprights. So any anchors installed in the top would almost strictly be subjected to tensile/pull-out stress. Which divided by the 12 anchors installed, may end up only being 200# max per anchor. PS, how do you like that Ellis? I passed on buying one a few years ago because I haven't heard great things about them in terms of reliability.John 3:16(2) Miller Pheonix 456(2) Millermertic 252Dynasty 210DXHobart 210MVPDoringer D350 SA Cold SawScotchman 350LT Cold SawWebb 10x50 MillWebb 15x40 LatheGeka Bendicrop Ironworker
Reply:Econ,Sounds like we're thinking quite similar as far as getting material in, storing it and being able to get it to the saw easily.   I sometimes pull those two saw horses out and set them up in front of the rack (in line with the saw) when I get an extra big bunch of material in for a job that I'm going to be sawing up right a way.  The uprights on the one I built are 3", 1/4 wall and the arms are 2", 1/4 wall.   I know I've had well over a ton of material on it at one time or another and didn't notice any problem with it wanting to bend.  Not saying it didn't flex forward some while under load but nothing you could really notice. I like that Ellis and it's one of the better band saws I've used on a production basis.   As long as I'm the only using it every thing stays in good shape and I can get very accurate repeatable cuts very efficiently with it.   All the problems start when I'm not around and people who really don't understand how to run a band saw get to playing with it.   This company had another Ellis saw set up in another shop which turned in to an un-useable piece of crap in short order.   After seeing how some of my fellow employees have gone about trying to use this one I'm pretty sure it wasn't the saws fault.
Reply:Blocks are designed for compression loading not side loading. I also suggest free standing racks. Dan D.Manipulator Of Metal
Reply:I would say build them like HT2 did his, and if your worried it might tip forward under load, then weld tabs to each side of the legs near the wall and anchor directly into the floor with 1/2" wedge type anchors. Put two anchors in on each side of each leg if it makes you feel better. That hollow block wall won't do as much for keeping it upright and is more of a PITA to even try.