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Fortress and Guardian Marine Anchors

Fortress and Guardian Marine Anchors
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Fortress Selection & Specifications Guide Guardian Selection & Specifications Guide Safe Anchoring Guide  
 

Fortress Selection & Specifications Guide  

Boat size recommendations are for boats of average windage and proportions in 30 knots of wind, average bottom conditions, and moderate protection from open seas. Remember that the loads in 42 knots of wind are twice as much as in 30 knots.

Use three-strand nylon line, 6-12 FT (2-4 m) of chain and a minimum of 5:1 scope. A minimum of 6 FT (2 m) of chain should be used for every 25 FT (8 m) of water that you usually anchor in. For storm conditions use an anchor one or two sizes larger.

 
FORTRESS SELECTION GUIDE
Model   FX-7 FX-11 FX-16 FX-23 FX-37 FX-55 FX-85 FX-125
Boat Length
 
ft 16'-27' 28'-32' 33'-38' 39'-45' 46'-51' 52'-58' 59'-68' 69'-150'
m 5-8 8-10 10-12 12-14 14-15 16-18 18-21 21-46
Weight
 
lb 4 7 10 15 21 32 47 69
kg 1.8 3.2 4.5 6.8 9.5 14.4 21.2 31.1
Replaces Steel Anchors lb 6-9 10-13 14-18 19-28 33-50 50-65 70-90 100-170
kg 3-4 5-6 6-8 9-13 15-23 23-29 32-41 45-77
                 
 
HOLDING POWER
Model   FX-7 FX-11 FX-16 FX-23 FX-37 FX-55 FX-85 FX-125
Working Load
 
lb 700 900 1,250 2,000 3,000 4,000 5,250 6,750
kg 320 410 570 910 1360 1810 2380 3060
32 Degree Hard Sand Holding Power
 
lb 2,800 3,600 5,000 8,000 12,000 16,000 21,000 27,000
kg 1,270 1,633 2,268 3,629 5,443 7,258 9,536 12,247
45 Degree Soft Mud Holding Power
 
lb 840 1,080 1,500 2,400 3,600 4,800 6,300 8,100
kg 380 490 680 1,090 1,633 2,180 2,858 3,674
32 Degree Soft Mud Holding Power lb 420 540 750 1,200 1,800 2,400 3,150 4,050
kg 191 245 340 544 816 1,089 1,429 1,837
                 
 
DIMENSIONS
Model   FX-7 FX-11 FX-16 FX-23 FX-37 FX-55 FX-85 FX-125
"A" Shank Length
 
in 24" 27" 31" 36" 40" 46" 51" 56"
mm 610 685 787 914 1,016 1,168 1,295 1,422
"B" Fluke Length
 
in 14" 16" 18" 21" 24" 27" 30" 33"
mm 356 406 457 533 610 686 762 838
"C" Stock Length
 
in 19" 22" 25" 29" 32" 37" 41" 45"
mm 483 559 635 737 813 940 1,041 1,143
 
SUPPORT HARDWARE
Model   FX-7 FX-11 FX-16 FX-23 FX-37 FX-55 FX-85 FX-125
Proof Coil Chain in 3/16" 1/4" 5/16" 3/8" 3/8" 1/2" 1/2" 1/2"
mm 5 6 8 9 9 13 13 13
Nylon Rope in 3/8" 3/8" 1/2" 5/8" 3/4" 7/8" 1" 1 1/4"
mm 9 9 13 16 19 22 25 32
Shackle Size in 1/4" 1/4" 5/16" 3/8" 7/16" 1/2" 5/8" 5/8"
mm 6 6 8 10 12 12 16 16


NOTE: Hard sand holding power figures above represent loads actually achieved on production FORTRESS and Guardian anchors under controlled horizontal pull conditions without dragging or resulting in disabling structural deformation.
** Rope recommendations are based on 25% of breaking strength. Rope must be in good condition.

 
 

Guardian Selection & Specifications Guide:


Boat size recommendations are for boats of average windage and proportions in 30 knots of wind, average bottom conditions, and moderate protection from open seas. Remember that the loads in 42 knots of wind are twice as much as in 30 knots.

Use three-strand nylon rope, 6-12 ft (2-4 m) of chain and a minimum of 5:1 scope. Also, a minimum of 6 ft (2 m) of chain should be used for every 25 ft (8 m) of water depth. For storm conditions use an anchor one or two sizes larger.
 
GUARDIAN SELECTION GUIDE
Model   G-5 G-7 G-11 G-16 G-23 G-37 G-55 G-85 G-125
Boat Length
 
ft 12'-16' 17'-22' 23'-27' 28'-33' 34'-41' 42'-47' 48'-53' 54'-62' 63'-72
m 4-5 5-7 7-8 8-10 10-12 12-14 14-16 16-19 19-22
Weight
 
lb 2 1/2 4 6 7 13 18 29 42 65
kg 1.1 1.8 2.7 3.2 5.9 8.1 13.1 19 29.3
Replaces Steel Anchors lb 4-6 6-9 10-13 14-18 19-28 33-50 50-65 70-90 100-170
kg 2-3 3-4 5-6 6-8 9-13 15-23 23-29 32-41 45-77
 
HOLDING POWER
Model   G-5 G-7 G-11 G-16 G-23 G-37 G-55 G-85 G-125
Working Load lb 350 575 750 1,075 1,625 2,500 3,500 4,625 6,000
kg 159 261 340 488 737 1,134 1,588 2,098 2,722
32? Hard Sand Holding Power lb 1,050 1,725 2,250 3,225 4,875 7,500 10,500 13,875 18,000
kg 476 782 1,021 1,462 2,211 3,402 4,763 6,294 8,165
32? Soft Mud Holding Power lb 210 345 450 645 975 1,500 2,100 2,775 3,600
kg 95 156 204 293 442 680 953 1,259 1,633
 
DIMENSIONS
Model   G-5 G-7 G-11 G-16 G-23 G-37 G-55 G-85 G-125
"A" Shank Length
 
in 19" 22" 25" 29" 33" 38" 43" 48" 53"
mm 483 559 635 737 838 965 1,092 1,219 1,346
"B" Fluke Length
 
in 11" 13" 15" 17" 19" 22" 25" 28" 31"
mm 179 330 381 432 483 559 635 711 787
"C" Stock Length
 
in 16" 18" 20" 23" 27" 31" 35" 39" 43"
mm 406 457 508 584 686 787 889 991 1,092
 
SUPPORT HARDWARE
Model   G-5 G-7 G-11 G-16 G-23 G-37 G-55 G-85 G-125
Proof Coil Chain
 
in 3/16" 3/16" 3/16" 1/4" 5/16" 3/8" 3/8" 1/2" 1/2"
mm 5 5 5 6 8 9 9 13 13
Nylon Rope
 
in 3/8" 3/8" 3/8" 3/8" 1/2" 5/8" 3/4" 7/8" 1"
mm 9 9 9 9 13 16 19 22 25
Shackle Size
 
in 3/16" 3/16" 1/4" 1/4" 5/16" 3/8" 7/16" 1/2" 5/8"
mm 5 5 6 6 8 10 12 12 16


NOTE: Hard sand holding power figures above represent loads actually achieved on production FORTRESS and Guardian anchors under controlled horizontal pull conditions without dragging or resulting in disabling structural deformation.** Rope recommendations are based on 25% of breaking strength. Rope must be in good condition.
 

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Safe Anchoring Guide

1. Determine Your Holding Requirements.
Be sure that your anchor can give the performance you need. A "Lunch Hook" Should be able to hold your boat in a 15 knot breeze. A main, or "Working Anchor" Should hold up to 30 knots of wind. A "Storm Anchor" is for winds up to 42 knots. Remember that as the wind speed doubles, the holding requirement quadruples!
 
Wind Speed
Boat Length in Feet
 
         
  20ft 25ft 30ft 35ft 40ft 50ft 60ft 70ft
15 kts 90 125 175 225 300 400 500 675
30 kts 360 490 700 900 1200 1600 2000 2700
42 kts 720 980 1400 1800 2400 3200 4000 5400
60 kts 1440 1960    2800 3600 4800 6400 8000 10800
 
Wind Speed
Boat Length in Metres
         
  6m 8m 9m 11m 12m 15m 18m 21m
15 kts 41 57 79 102 136 181 227 306
30 kts 163 222 318 408 544 726 907 1225
42 kts 327 445 635 816 1089 1452 1814 2449
60 kts 653 889    1270 1633 2177 2903 3629 4899

Use the handy "Horizontal Loads Table" above to determine in pounds your holding power requirements for different wind speeds. NOTE: This table assumes boats of average beam and windage. If your boat has above average beam or windage, refer to loads for the next larger size boat. The numbers in columns for feet = lbs., and the numbers in the columns for meters = kg.

2. Use Adequate Scope.
Scope is the length of anchor line relative to the distance from your boat's deck to the sea bottom. We recommend at least 5:1 scope.

At 10:1 the holding power will double, and at less than 3:1 you will give up a significant amount of holding power and may experience problems setting the anchor.

SAGPic1-01

In crowded anchorages "Power Set" your anchor at 5:1 scope, then shorten scope as required. Remember that your depth sounder may be giving you the water depth under your keel, rather than from the true waterline, in which case you need to add your draft plus the height of your deck when calculating scope.


SAGpic2-01


3. "Power Set" Your Anchor.
Know that your anchor is properly set! Back down very, very slowly. Then as the anchor begins to set, very slowly increase the load with your engine. Backing down at any speed at all may not give your anchor a chance to dig in and bury itself.

You can simulate the force of the wind by using your engine's thrust to set your anchor to a predetermined load. Match your boat's total maximum horsepower and hull type in the table to determine how hard your boat can"Power Set" your anchor.

SAGpic3-01

4. Anchor Resetting.
In areas of changing tide or wind, set two anchors off the bow in opposite directions. Any anchor can occasionally fail to reset once it has been pulled out of the bottom.

Don't be fooled by some manufacturer's claims about any anchor's ability to dependably reset 100% of the time! Set two anchors if you expect a change in wind or current.

SAGpic4-01

5. Anchor Retrieval.
Slowly move the boat to a position directly over the anchor, pulling in the line as you go. Then snub the line on a cleat and power backwards slowly to pull the anchor out of the bottom. Do not power forward because that will require more energy and put very heavy loads on the anchor and gear.

6. Support Hardware.
Remember that your anchor system includes the shackle, rope, chain, and deck cleats. Every item must be able to deliver the strength you need. Refer to the handy selection guide on the previous page.


7. Anchor Rode.
Use a short length of chain and three strand nylon line. The nylon is very elastic and greatly reduces shock loads on your boat and it's anchoring system. The chain protects the line against chafe from the sea bed and also help provide horizontal pull on the anchor when it is initially beginning to set. If you regularly anchor in 25 ft (8 m) of water or less, use 6 ft (2 m) of chain. For greater depths, use 6 ft (2 m) for every 25 ft (8 m) of water depth. (ie: use 24 ft (7 m) of chain if you regularly anchor in 100 ft (30 m) of water).

All chain anchor rodes lack the shock absorbing ability of nylon rope when the wind pipes up!

SAGpic5-01

8. Soft Mud Bottoms.
All soft mud bottoms offer greatly reduced holding power, so be sure your anchor can provide the holding power you need. Some bottoms offer as little as just 15% of the holding available in firmer bottoms!

Some soft mud bottoms have a sticky consistency which makes them difficult to set an anchor in. If soft mud setting problems occur, try setting the anchor initially at very short scope, e.g. 2:1. Then, increase the scope to at least 5:1 and "Power Set" the anchor. Special "Mud Palms" are included for both Fortress and Guardian anchors to aid setting in very soft problem mud. We recommend that you install the "Mud Palms" on your anchor, as they help the anchor set faster in any type of bottom.

SAGpic6-01
 

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