Originally Posted by windship
I would not use a plow anchor. Their not good in sand. Don't use only 1 style of anchor and don't use only one. What type of bottom do you have?
If you are in sand and mud with no rocks or grass, I would use a huge danforth style anchor or two with alot of over sized chain (10 to 1)and 3 strand nylon snubbers.
If your area has rocks and grass then you'll foul your anchors if they drag, if they pop out and won't reset (danforth's).
I must comment on this. It depends to some extent on how you rig the tandem system and how you deploy it, but in general terms you should always use anchors of identical types
in a tandem set-up.
The reason is that you cannot normally get the tandem anchor (the forward most one) to set, if you deployed it after the primary, as your boat will not have enough power to drag the primary. You can try to set both anchors at once by getting skilled with the amount of resistance on the gypsy brake (or no windlass?) combined with reverse engine, but you will still at best end up with both anchors only half-set.
If you have set one anchor but the other is of a different type, you cannot trust that it will set - if they are of the same type, then if one sets the other should, assuming the bottom is fairly consistent.
Danforths are absolutely not to be used in this kind of scenario
for all the same reasons they should not be used as serious primary anchors in any situation.
Use the heavier anchor as the primary. A boat length of chain between the two. Have you thought about how to deploy, as I touched on above? Etc. We frequently set-up boats with rigs to handle high lattitudes cruising (Greenland, Alaska, up your way, Patagonia, Antarctic, down here) where all the cruising guides have chapters on tandem anchoring
so feel free to ask for advice.
Originally Posted by hastingsml
I need an oversized anchor for riding out hurricanes in NC. I plan to put out two Delta plow anchors. I want one to be oversized and have been told to get one the next size too big.
The boat is 26' and weighs 6700 lbs. Should I go 22 lb or 35 lb.? I will be using chain and line rode.
Okay so leading on from above, your original plan is more or less okay. Nothing really wrong with two Deltas, at least not in sand, although you could do better.
As far as size is concerned, we recommend a Rocna 10 (22lbs) for your boat, and that's rated at that LOA to 5 tonnes. For a plow you need to compensate for the lack of fluke area, so maybe go to the 15Kg, and use the 10Kg as your working anchor. What do you have already? - If you're looking for new anchors from scratch, then abandon the plow idea, you can do better. Spade / Rocna / Bulwagga.