How to remove concrete screws

[WhiteD3]

Hiya,

I have a pool fence around a salt pool. Some of the posts need to be replaced as they have rusted through at the base. Each post is bolted to the concrete by concrete "screws". Something like this Ankascrew (http://www.ramset.com.au/public/Article/show.asp?ArticleID=1105&menuItemID=181&toplvlID=3&menuNo=0)

Obviously they were cheaper than loxons or dynabolts!

Question is, how do you remove them without breaking the head off, as happened with the last post I replaced.

The posts and screws have been in place for 6+ years.

Cheers.

[amtravic1]

They should just unscrew. I use them all the time. Obviously someone has not used the correct grade screw. They have probably used the standard screws and not gal or stainless wich would have been more appropriate given the salt water environment. I suspect the screws have corroded and will most likely break when removing them.

Ian

ps, they are more expensive than dynabolts by about 3-4 times but much easier to use and give a neat finish when a structural fastener is not needed.

[colrospeake]

I would put a bit of wd40 arround the base of the post in a little dam of blue tack. Let it soak for a day or two refilling when nessary. This will loosen any corrossion that has occured. The gently tap the head of the screw to crack the bond - gently screw them out . If that dont work - angle grinder and a new hole beside the ground of old screw.
Best of luck
col

[harry]

when i have something that i know isn't going to undo, and will stuff everything in getting it out, i go for the tighten it until it shears the head off, only problem in your case is that the hole is unusable after breaking the head off [if these things do that]
otherwise drill the head off and drill the remains to fix another bolt into.
i hope this helps.

[WhiteD3]

Thanks guys.

The problem with snapping the head off and leaving the bolt there (which is what I've done for the first post I had to replace) is that as the bolt degrades in the hole it leaves a rust stain on the concrete.

I tried drilling out the bolts with a (titanium drill? bought for the job) but no joy.

[Bigbjorn]

Thanks guys.

The problem with snapping the head off and leaving the bolt there (which is what I've done for the first post I had to replace) is that as the bolt degrades in the hole it leaves a rust stain on the concrete.

I tried drilling out the bolts with a (titanium drill? bought for the job) but no joy.

Get a drill with left hand helix and run it in a battery drill in the opposite direction to a normal drill. The cutting thrust will unscrew the bolt. Works a treat. Better than Ezyouts and other types of broken stud removers. you will have to go to a supplier of machine shop requisites.