Woodscrew suggestions

[Cursitor Doom]

Gentlemen,

I need to extract some old fence posts that have rotted off at ground level (as they do). Most common extraction method on YT seems to be to screw a plate with a lifting eye to the old stump and jack it out. I'm just wondering which type of screw would be suitable for this. They'd need to be perhaps as much as 200mm long (these posts are *in* a way) to get sufficient purchase into the heart of the wood lower down which hopefully is more sound than at the surface. They also need to have a shank of 10mm to fit through the holes in the extraction plate to best effect. I'm thinking maybe something that isn't even meant for wood might work best here, but am not at all sure. Any suggestions? The posts are 4" square and go down about 3 feet.

CD

[Davidm]

How about concrete screw bolts. Screwfix have got them 150mm long, if this is long enough to get into sound wood.

[Tim+]

Ground anchor screw?

The threads of the screw are probably too big to screw into anything other than very rotten wood but if you have a bench grinder to could reduce the diameter of them. You would probably need a pilot hole though.

Tim

[The Natural Philosopher]

coach screws are perfect

[Chris Green]

I use a set of 300mm x 10mm coach screws to do this. I'm lucky to have a tractor with a hydraulic three-point lift on the back so I just use a short length of chain with a couple of screws through the holes and pull up with the tractor's lift. It sometimes takes a couple of goes but it has always worked in the end.

[GB]

Are you going to put new posts in?

[Cursitor Doom]

Yup.

[GB]

Won't you need to dig post holes and add concrete?

[Cursitor Doom]

Sorry, I'm not very good with metric. Is that 10mm shank or 10mm socket fitting for the hex-head?

[Chris Green]

10mm shank, the heads are 19mm spanner size.

[Chris Green]

If you pull the old post out the new one drops neatly into the hole. In general concrete is a 'bad thing' in terms of post lifetime, the post will usually last longer if it's just direct in the ground.

[Cursitor Doom]

Excellent. Many thanks.

[Cursitor Doom]

The posts are surrounded by about 10" square dollops of concrete. I'm expecting to pull out posts and dollops in one go as I have a crane. The tricky bit is interfacing the crane with the rotted post; hence the original question.

The post might well last longer; the fence probably won't!

[Fredxx]

Any reason why you can't use a fence repair spike like:

You might even place the old broken off post into the clamp? Win-win?

[Cursitor Doom]

I did consider that solution, but don't feel it'll last as long as re-doing it the old-fashioned way. Plus I don't go for easy solutions; I like to make everything as hard as possible for myself.

>

[Chris Green]

Well none of my posts have ever fallen over, I guess it depends on how far into the ground you drive the post and how solid the ground is.

[Animal]

I don't think a bird would be strong enough

[Cursitor Doom]

Not really an option for me as the ground hereabouts is *really* hard and stoney so has to be 'excavated' anyway. No chance of driving anything into it.

[Brian Gaff]

I never got far with this kind of thing, when I was a younger man it was normally a dig it out job, sadly. Nowadays, just get a bloke in. Brian

[fred]

I've been preachng this for years, based on pesonal experience