UKC

Have been off for 14 months after shoulder surgery and have been reading anything and everything to pass the time.Now I dont normally read a lot of books prefering to go out and do things instead.My question (appologies if its been asked before) is how do you place your ice screws.Ive been reading a couple of books and one states always at 90 degrees to the ice and the other states hanger down in good ice.Never really thought about it before just wondered what other folks on here do.

In reply to Removed User:

http://www.needlesports.com/advice/placingscrews.htm

In reply to Dee: Cheers,not read anything from here before.Looks like some well informed articles.Do all screws have the same depth of thread.

In reply to Removed User:

No. Some have full length threads (the shorter ones), and some have partial threads (usually longer ones). IMHO full threads are better in case you pass through a layer of ice into an air pcoket.

In reply to Dee:

The needlesports article backs up previous research on belay stake strength that was carried out (and mention on here not too long ago).

Basically, the research found that stronger placements could be made with a positive angle (ie the top of the stake nearer the route than the buried tip of the stake).

The reasoning behind this, is that it is the friction of the placement (the friction between the stake and the ground) that provides the strongest attachment, rather than a negative angle (pointing away from the route) which is the intuitive way to place a stake. When placed in a negative angle, any load applied forces the stake to cut it's own channel through the earth, loosening the stake and reducing friction with the earth.

The same stands for ice screws, where it is the friction between the thread and the ice that provides the holding strength rather than the angle.