No announcement yet.

Concrete Drop-In Anchor question.

  • Filter
  • Time
  • Show
Clear All
new posts

  • Concrete Drop-In Anchor question.

    I have to mount a hand rail to my concrete porch and am wondering about the type of anchor to use.

    I want to be able to take the rail off so if I ever need to move furniture. I have been told some types are problematic and can get loose and spin in the hole making them a real pain to get apart.

    Whats are the good ones like? I dont want to buy the wrong type.

  • #2
    I still like the lead type that use a lag screw to bolt something down. You can take out the screw and fill the hole if you ever needed to.


    • #3
      I prefer the type that goes in as a stud rather than as an anchor for a lag screw. I think Redhead is one brand name. They anchor better. With a traditional lag screw anchor, when you remove the lag screw, the anchor can fall down in the hole.

      With these anchor studs, you drill a hole carefully to get the depth right so that the back end of the stud bottoms in the hole and then you whack it. It expands a ring outward. Drill too deep and you will be sorry as you won't be able to force the expansion that makes them work. A piece of masking tape on the drill at the proper depth solves this problem and the flag it forms pushes the loose concrete powder out of the way as you are drilling, too.

      The down side to this, of course, is that you no longer have something that is flush--the studs stick up even if you have nothing attached to them. However, for a hand rail, you still accomplish what you are after if you remove the nuts and the rail....a wider path in which to carry bulky stuff.

      Paul Carpenter
      Mapleton, IL


      • #4
        I prefer the type with the split cylender and a wedge shaped bolt or nut.
        they seem to hold better than the type with the slotted cylender. (and are easier to remove)

        If you drill the hole about 1/4 inch deeper than the bolt is long, the anchor won't drop too far to catch when you reinstall it.

        I've got a couple things in the garage that I anchor when in use, but move when stored (shaper for one, very small shop) and that's what I do. Duct tape or plugs keep the anchors from getting filled with crud when not in use. Also use the bolt not stud type
        That way I have wide open floor space, and securely mounted equipment when I need it.



        • #5
          I've used Star Tampin (brand) anchors. They're a tapered threaded core surrounded by a lead shield. You drill a hole the correct size, drop in an anchor, and expand the anchor by hammering on a special seating tool. They're at the top of page 3212 of .Mcmaster has a lot of different styles of concrete anchors -- they ought to have something that will work.
          Try to make a living, not a killing. -- Utah Phillips
          Don't believe everything you know. -- Bumper sticker
          Everybody is ignorant, only on different subjects. -- Will Rogers
          There are lots of people who mistake their imagination for their memory. - Josh Billings
          Law of Logical Argument - Anything is possible if you don't know what you are talking about.
          Don't own anything you have to feed or paint. - Hood River Blackie


          • #6
            I thought about studs and epoxy, or even a little epoxy on the anchors so they cant ever spin in the hole.

            I want to get this project done before winter hits. All I have left is to drill the porch and set anchors, mount the plates, weld the railing to the plates, remove and paint the rail and remount it.

            Here is the porch.

            The top peice.

            This is the stair peice.


            • #7
              I hate to say this now, but why didn't you make the railing a bit larger,
              and run the post's, down the sides of the concrete steps, say 9" or so ?
              this would take the railing mounting holes away from the fragile edge
              of the concrete (which wants to break out) and allow you to put
              in studs as deep as you want, and when you remove the railing,
              the studs are not a problem, in fact they help you in re-hanging.

              This how I did it on my sisters place, very similar steps.

              It also helps when you sweep the steps, there is no post to
              sweep around.

              If you run the post's down alongside, a 45 degree cut on the end
              looks nice.


              • #8
                I've had great success with Simpson Titen HD anchors. Not real cheap but reliable and removable. I get them at Lowe's.



                • #9
                  looking at the layout, I think I'd have built them with a gate accross the open side, either hinged or lift out. that and a set of ramps (or pair of strong backs) would get anything through the door.



                  • #10
                    I just bolted my shop to the slab with the titen hd's. Make sure to use a beefy hammerdrill with the right size bit because they are very sensitive to hole size. My wimpy hammerdrill seemed to drill a tiny bit undersize with the same sized bit as the big bosch. As long as you don't cross thread them if you have to remove and reinstall the bolt, it's like putting a screw into steel almost.



                    • #11
                      I just talked to a rich friend and he said to buy the anchors from the guys who rent the hammer drill, they have the good ones..

                      People who pay for powder coating are way too rich for me.

                      I think I will go with lead anchors and drop a little epoxy in the holes so they dont spin later, I think that will work.


                      • #12
                        Unless your steps are unusual they are about 3 -4 inches thick. The rest is fill. Look closely around the top slab and you will probably see a joint. I think your best bet is add a piece to the section attaching to the house and extend the post down the side anchoring them to plates as already suggested.



                        • #13
                          Originally posted by Bob Ford
                          Unless your steps are unusual they are about 3 -4 inches thick. The rest is fill. Look closely around the top slab and you will probably see a joint. I think your best bet is add a piece to the section attaching to the house and extend the post down the side anchoring them to plates as already suggested.

                          If my mom is so fat she can pull the anchors out then I will foot the bill and buy her jenny craig grubbin.

                          I will get it done and it will be quality.


                          • #14
                            I would suggest epoxy. It doesn't create the concrete splitting forces when torquing the fastener that expansion anchors do. That is important if you are near an edge.

                            The bonus is they can be removed by heating the threaded stud with a torch. When the epoxy softens (about 500 degrees) it will pull right out.


                            • #15
                              I'll second the Simpson Titen fastener recomendation, they're self threading and can be reinstalled in the same hole. Wedge type fasteners create a side force to hold them in and can cause the sides of the concrete to spall or break out when used close to an edge.