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Vandal proof SS anchor bolt

Vandal proof SS anchor bolt

Vandal proof SS anchor bolt

(OP)
Has anyone come across a vandal proof stainless steel anchor bolt, or preferably a chemical or mechanical anchor that can be made vandal proof?

RE: Vandal proof SS anchor bolt

Nothing is really vandal proof.  Tack welding the nuts cannot prevent a determined vandal from destroying the connection.

RE: Vandal proof SS anchor bolt

Shift the assembly/ joint down so that the anchor bolts are below grade, and pave over them.

Mike Halloran
Pembroke Pines, FL, USA

RE: Vandal proof SS anchor bolt

Have you considered welding or rivets?

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RE: Vandal proof SS anchor bolt

unless you have a heating torch, you'll find the Locktite product very secure.  Heating it with a torch will allow you to remove the nut.

Dik

RE: Vandal proof SS anchor bolt

There is no product the is vandal "proof".  What is available provides differing degrees of resistance to tampering.  You have to decide what level of resistance that you need to have and then make a decision based on that.  The differing proprietary drives have differing lavels of resistance depending on how difficult it is to buy or make a driver. The Tamper resistant Torx Plus is pretty good because it has an odd number of lobes so most regular drivers can't be modified to fit.  If you combine something like that with an adhesive you have a system that is pretty resistant to tampering, but given enough time it can still be taken apart.
By far the most resistant connection involves the use of a welder.  There is nothing like fused steel to deter most vandals.  But once again, given enough time even that can be defeated.  I've seen what a guy in prison with 5 years of work can do to a welded joint.....

RE: Vandal proof SS anchor bolt

a bit of a caution... welding some bolts can cause embrittlement... and early fatigue failure

Dik

RE: Vandal proof SS anchor bolt

How determined are these vandals?  What is being vandalized?

rmw

RE: Vandal proof SS anchor bolt

Most of the rotary broaches we make for security solutions are a hexalobular form or custom form the customer specs for his fasteners. We make the broach, internal or external, and they use it with the holder to produces 100's or 1000's of fasteners which use that form. The picture from the product search page of our website (below) shows a variety of broaches and products made using this principle.



 The video on our website explains how to do it on a CNC or screw machine. It seems the medical community is starting to specialize in these fastener options to control their niche with bone screws and other orthopaedic products.
www.slatertools.com

RE: Vandal proof SS anchor bolt

Is having the contractor damage the threads too low tech of a solution?

The company I work for has a standard note on many anchor bolt details, that calls for upsetting the threads after the base plate is installed.

I don't really know what upsetting the threads means.  However  I have never gotten a call from the field from a contractor asking me how to upset the threads.  Maybe they just hit them with a big hammer.  

RE: Vandal proof SS anchor bolt

>>I don't really know what upsetting the threads means.  ... just hit them with a big hammer.  <<

That's exactly what it means.  

Mike Halloran
Pembroke Pines, FL, USA

RE: Vandal proof SS anchor bolt

(OP)
Thanks all for your comments.

These are all for stainless steel signs for a park in new york. I have seen too many of these things vandalised and wanted to see what the options were.

Will see how they survive with standard anchors.

RE: Vandal proof SS anchor bolt

We have done some highway and street signs using some small Huckbolts.  You gotta cut those things off with a torch.  

RE: Vandal proof SS anchor bolt

If you're just looking at holding a sign in place, a relatively inexpensive way to prevent someone from unthreading a fastener is to use a longer bolt than necessary. Saw a slot in the end of the bolt down to the point where the back of the nut should stop. After threading on the bolt (probably with some effort if the bolt isn't well deburred) stick a chisel in the slot and pound on it to spread the end of the bolt. It will be almost impossible to remove the nut.

RE: Vandal proof SS anchor bolt

I have come across this company operating out of Canada http://www.boltmate.com, they do a two part nut that has an inverted conical center with a matching outer ring. The outer ring is laser welded to the center cone, when you torque the nut to the specified load - the laser welds self destruct and you have reasonably secure joint. They proclaim to be selling this fastener to Power pylon companies for use against vandalism.

 

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