Is it possible to use molly bolts in concrete? They are generally described as for use in drywall. But I have a project that needs a hook or screw to be taken out from time to time, which is possible with a molly bolt. The load on the hooks would not be significant.
If it isn't possible, is there any other way of achieving this? Most anchors for concrete don't permit multiple insertions and removals of the screw.
A machine screw anchor is a good option for repeated removals and reinstallations. They're also available in standard thread sizes, so they can accept machine screws, eye bolts, or hook bolts. The downside is that you'll have to buy an inexpensive but specialized setting tool for each size of bolt you want to install.
The installation process is much like that of the lag shield below, except that you'll have to use the setting tool (third step) to seat the machine screw anchor into the hole.
A lag shield anchor may be another acceptable option, but it is not as "reusable" as a machine screw anchor. It creates a sleeve inside the hole in your concrete with threads for a lag screw to grab onto. When the lag screw is inserted, it expands the shield inside the hole.
The installation process:
The lag screw will still be removable, but keep in mind that many repeated removals and installs may eventually weaken the anchor.
(I have no affiliation with either distributor, they just had good illustrations.)
No, they won't work there... but there are similar expanding anchors that CAN be used in concrete, with threaded holes so you can remove/reinstall hardware at will. Don't get the lead (lead metal) ones, get the steel ones. You can even get some with male threads, onto which you could install a loop nut.
