Your BEST investment for “peace-of-mind”; a Mantis Anchor!
Every night, every time you leave the boat and every time the wind pipes up at midnight, your home and all of your belongings are pinned precariously to the bottom by your anchor and rode. So why would you entrust all this to anything less than the best anchor available?
After over 60,000 miles of cruising and anchoring 2 or 3 times a week using a combination of a 45lb CQR and a 45lb Danforth anchors with 80 feet each of 3/8″ chain backed up by 100 ft each of 1″ nylon rode, we decided to re-evaluate our ground tackle on Sampatecho II. It wasn’t that we were dragging with any regularity, although we had on occasion and it wasn’t that the 400 lbs on the bow hurt our performance severely although we did ride a little bow-heavy and “stuff” more big seas than I like. Ultimately, it just came down to placing more value on a good night’s sleep with fewer anchor-watches and midnight re-sets.
So, a little over a year ago, the search for a new anchor began. Like any other cruiser, I began reading magazine articles, surfing the Internet, checking out boat show exhibits and seriously talking to other boaters. You would think that boaters would be the best source of reliable information but I soon discovered that ground tackle runs a close third to politics and religion when it comes to subjectivity. Even the guy with a bucket of rocks thinks he has “the ultimate anchor”! From our own experience, we were ruling out the traditional anchors; Bruce, Danforth, CQR and Delta which, when properly set, are good in many conditions but definitely not ALL conditions.
We’re searching for the Holy Grail of anchors which would set immediately in sand, mud, marle, rocks, gravel and kelp, hold with 5:1 scope through gale force winds and re-set just as quickly should the tidal current reverse and pull in the opposite direction. It took about 4 months but we narrowed the field down to 5 contenders; Rockna, Spade, Manson and Mantus. I had some experience with each of these from deliveries or friends’ boats and all had worked faultlessly in my limited use. Each had “independent” testing to prove their supremacy and each had design differences to point to as their secret to success. The next 8 moths would determine which one was right for us.
Manson was the first to fall under scrutiny. The slotted shank may have some benefit in retrieval but my fear is that it could also dislodge the anchor in a reversing tidal current and weaken the shank in lateral forces when anchored in rock.
The Spade was next to fall because it lacked a roll bar to get it upright in all conditions especially soupy mud. It’s shape was great for biting into all surfaces but I feared that the lack of “righting ability” could be a problem in reversing current when a scoop full of goo could just ride along on top of the shank as we’d witnessed with Deltas. Lack of a retrieval mechanism in the event of fouling on cables, chains etc was also a concern.
Rockna had been my early favorite; used by such notables as Nigel Calder and the first to introduce the “roll bar” to orient the base quickly and effectively, I still believe it a great anchor and would recommend it heartily. It sets quickly, holds well and re-sets quickly too. It would be my choice except for the ultimate selection that we discovered thanks to two new cruisers from Texas on our old “buddy-boat” Our Way.
Mantus was developed not by an engineer but a doctor who was also a boater who borrowed from existing technology to produce the anchor of our dreams. It too has a roll bar to orient the anchor as soon as it hits bottom then the blade shape takes over. Unlike the Rockna, the Mantus has extensions or ears that stick out to hold the roll bar. These ears apply further force on the blade tip to get it to dig-in instantly. This and the ability to retrieve a fouled anchor with a grappling hook , price and warranty made it our choice for purchase and evaluation. The Mantus comes with “some assembly required” but it is so straightforward that instructions are not necessary and all parts are supplied. It takes all of 15 minutes to bolt it all together. While this had initially been a concern, the bolts are massive. We also opted for a slightly over-sized 65 lb model although we could have gone with a 45. We chose the larger size as it enabled us to replace the existing secondary 45 lb Danforth with 80 feet of chain by a Fortress stowed in a cockpit locker thus saving a net wight of 150lbs from the bow. The 65 is a tight fit (see photo) and may be over-kill, but this whole exercise is about total confidence and sound sleeping at anchor.
To test this, when anchoring, we zoom-in the chart plotter and drop a waypoint exactly where we drop the anchor. If we approach it from the same direction on departure the point should be the same. (The GPS antenna is 40 feet behind the bow so that has to be considered each time when we retrieve it.Day 1: Lake Sylvia, Florida -soft mud, little wind, no wave actioSet instantly, held fast absolutely no drag.
Day 2: Dinner Key, Florida – sand, 10 kt wind, lots of powerboat wake
Set instantly, held fast, no movement
Day 3: Channel Five, Florida Keys – sand, 1 kt current (reversing) 10 kt wind
1 -2 ft seas occasional wake.
Set instantly, held fast, less than 10 ft movement
Day 4: West of Boot Key, Florida- sand, 1kt current, 10 kt wind, 2ft seas but
lots of powerboat wake
Set instantly, held fast, absolutely no movement
Day 6: Key West Channel, hard bottom, 2kt current (reversing) 15-20 kt
wind, 2-3 ft seas and lots of sport fisherman wake. THE BIG TEST;
With wind and tide opposing, this and seas rolling through unabated
from the north; this would be a real trial.
Anchored in 24 feet, we laid 80 feet of 3/8″ chain and another
40ft of 1″ nylon rode (total 130 ft) and greatfully had lots of swing-
room as the fluky tide and assortment of boats in this Harbour creates
mayhem as each one react differently to the high wind and strong
current . Set first time and held fast.
Day 7: Lake Sylvia, Ft Lauderdale hiding from a Cold Front. Mud bottom 10 feet deep crowded anchorage. 15 kts SW wind little current. Set instantly.
As wind swung around to NW then NE it picked up to 18-20. We held fast but the 50ft Hatteras beside us dragged slowly into the pilings of a private residence. Just as it reached the piling, we got a line on the bow and hauled her back into the anchorage but now the Mantus would need to hold our 44 ft sailboat and a 50 ft Hatteras with lots of windage AND tonnage. We called TowBoat US in case we couldn’t save her but there was no need! The Mantus held us both without dragging at all in the soupy bottom! We’ll be talking to the owner about upgrading to an anchor that HOLDS. The damage avoided today will easily pay for a stainless steel model. Well done Mantus!