Thanks for the responses...I would like to know some more about using a stern anchor. I will be spending a fair amount of time anchoring on my home river and I think using one will be needed to keep the boat from blowing around. I realize I will need to know when the tide changes and pull and re-set the rear anchor when that happens so...what is the best way to deploy the anchor and then pull it and re-set when the tide changes without having to re-set the bow anchor and will it the bow anchor re-set on it's own when the direction reverses. The river is mostly muddy bottom. Use dinghy to set/retrieve stern anchor? I am looking to get a danforth to use for the stern anchor.
I use a Fortress FX11, 6' of 3/16" chain, and around 300' of 1/2" three strand nylon. It's set up in a milk crate where I can tie the bitter end off through a hawse pipe to a cleat on my stern deck. The anchor and chain sit on top of the rope in the crate. I figure out where I'm going to drop the bow anchor, mark it on the chart plotter as MOB and start moving to where I want to drop the stern anchor. My MOB mark will give me distance back to the mark on the plotter. When I get to where I want the stern anchor, I position the boat towards the MOB mark and give it a slight forward motion. Run back; throw anchor and chain behind the boat; run forward and put the boat in gear. The rope needs to be set in the box or on the deck where it will self deploy without tangling. Slowly motor up to the MOB mark,leave the boat in neutral and drop anchor and chain quickly. Then go to the stern and pull the slack out of the stern anchor rope till the bow anchor draws tight. Once the slack is drawn out of the stern anchor rope, you can set the bow anchor and make adjustments.
Now I do this all solo each time I use 2 anchors. With someone to deploy and keep the stern anchor rope from slacking and going into the prop, it would be much easier. In a perfect world, I want 20:1 scope on the stern rope. That little anchor has a tremendous amount of holding at that scope. With 200' of stretchy line out, the line acts like a shock absorber to soften the boat tugging. After the bow anchor is set, I pull the stern rope very taught to hold the boat in place.
To leave, I slack the stern anchor intermittently while pulling the bow anchor. When the bow anchor comes up, I go pull the rope on the stern anchor, pulling the boat to it. When the rope is near vertical, the anchor usually breaks out of the bottom. Once or twice I tied the rope off when it's vertical, and let the mass of the boat break it out.
If you have the good fortune to do this with a mate, practice it a few times, lots of moving pieces. In a perfect world, I want all the stern rope deployed and the line starting to stretch as I'm dropping the bow anchor. 300' of 1/2" three strand nylon will easily stretch another 50'.
Ted