Fortress and Guardian Marine Anchors

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.

 

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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.



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.





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.



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.



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!



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.


 

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