Anchoring and Storm Tackle [Updated Dec-2024]

  ➛ ➛ From our list of Stuff we have and use [and do...] in the right sidebar ➛ ➛   

This is part of a series describing some of our common boat systems and their operation.

We refer to these often not only for our own use, but also when asked specific questions about systems on Denali Rose, and when participating in discussions on various forums.

We aren't implying our choices are the best or only way to go; they just happen to be the decisions we made [...or sometimes what came with our boat...] 

We also include relevant, qualified links to external resources on the topic.

__________________

Background: 

Denali Rose is 50 ft. LOA and displaces 22+ tons cruising weight. We typically frequent deeper anchorages above 56°N. [e.g., We anchor in 50 to 90 ft. of water about 80% of the time, with the remaining 20% spent at anchor in 30-50 ft.]

We adhere to the philosophy of setting one recent generation [AKA 'Modern'] oversized anchor and sleeping well...

However, we still keep two different anchors on the bow [either of which can serve as a best bower] to optimize anchor choices for different bottom types. And occasionally we need to set a hammerlock moor. [Which can be tricky with our bobstay...]

Also, we have grown accustomed to having a hot spare ever since having had to abandon one once in an emergency [decades ago... And this is still a viable tactic in many situations- with the goal of returning to retrieve it in the future.] Another time [also decades ago] we lost our bower anchor that could not be retrieved despite trying all the typical retrieval methods for two days... [Diving was not an option for us on that occasion: 38°F water at 90 feet of depth...]

Remember we are typically in fairly remote locations, and obtaining a replacement main bower takes several weeks at least...

And finally, before getting started it is worth noting that the anchor roller design on our boat's bowsprit does not accommodate anchors with roll bars. Therefore we don't have any...

––––––––––

Ground and Storm/Safety tackle inventory on SV Denali Rose

Both bow anchors in stowed positions

Both anchors lowered slightly to reveal anchor rollers...

These two photos demonstrate how the primary bowers are secured for transit in rough weather.

Anchor inventory: [6 total; we frequent remote areas, and have lost anchors before...]

• Spade [Model S180 galvanized steel; 45 kg / 99 lbs; primary bower; rated for vessels up to 75 ft, displacing [weighing] up to 57,300 lbs. [Denali Rose is 50 ft. LOA @ 44,000+ lbs. cruising displacement.]

Spade [with removable shank]

• Excellent performance in most bottom types
• Performance declines in soft mud and ooze (very soft mud)
• Self stows beautifully on our bow sprit
• Self deploys from anchor roller on bow sprit
• 45 lbs. of lead in the tip [i.e., 45% of the anchor weight is the tip...]
• Works well in short scope situations— especially in deep anchorages
• Setting technique is the same as the SuperMAX anchor [scroll down to mid page]
• From personal experience, our Spade requires >2.5:1 scope to set properly in depths less than 50 feet- matching SuperMAX setting recommendations linked above
• Lifetime warranty
• Post about retrofitting new Spade as best bower

Note: This anchor is 2+ sizes larger than the minimum recomended size on Spade's sizing chart [below]. Ignoring boat length, we chose our anchor— consulting with the manufacturer— based upon our [perhaps] higher than average windage, and cruising displacement [44k lbs] along with our desire to frequent higher latitudes.

The model 140 [66lbs] would have likely been adequate for most of our needs. But because we like to sleep well, and since we can easily fit a larger anchor [up to the S200 (121 lbs) by my measurements] we consulted with the manufacturer and took their advice to go up two sizes.

 Spade Anchor Sizing Chart

• Minimum based on partially laden displacement [not cruising weight]
• Minimum based on actual [measured] cruising weight [44k lbs]
• One size up from minimum
• Two sizes up... [Our choice- based upon manufacturer recommendation for our specific needs...]

Boat  LengthFt	Boat  Weightlbs	Anchor  Model	Galvanized Weightlbs	Aluminum  Weightlbs
21	<2,200	40	12	6
24	<4,850	60	21	10
34	<9,920	80	--	15
41	<14,330	80	33	--
52	<26,450	100	44	26
59	<35,270	120	55	--
65	<44,000	140	66	41
75	<50,700	160	77	--
75	<57,300	180	99	--
82	<66,130	200	121	57
98	<88,100	240	165	-

• Super MAX [Model 20 (One size larger than 'needed'...); adjustable shank angle; 80 lbs; secondary anchor ready to deploy on bow; rated for 55,000 lbs. displacement vessel in hurricane force winds @ 5,000 lbs. holding force.]

SuperMax Adjustable

• This is a lesser known, excellent anchor that performs well in all bottom types: [Adjustable shank; 3 angles; first set at 3:1 scope, then set again at 5:1 scope for all bottom types.]
• Sand, hard mud, and coral use a 5:1 scope and the lowest hole adjustment (smallest fluke/shank angle)
• Mud, use a 5:1 scope and the middle hole adjustment
• Ooze or very soft mud use a 5:1 scope and the highest hole adjustment (largest fluke/shank angle)
• Setting technique? SuperMAX describes it best.
• In tight anchorages, using an all chain rode, you may move the setting to a more open position and reduce the scope to 4:1
• In deep anchorages [e.g., 60-90 ft.] we strive to maintain 4:1 scope, but sometimes are limited to 3:1 at high water. [Which is still very acceptable and reliable in deep water anchorages. See articles in references section, below.]

Note: We never set 2 independent anchors simultaneously. [The last time was 25+ years ago when both anchors were CQRs on a different vessel...] Instead, the secondary anchor is there in case conditions warrant its use instead of the primary bower, or if we lose use of the primary bower for any reason. 

New Spade S180 on left in photo [Jan-2017]; Used SuperMax on right 

Spade S180 stows in bow roller without manual intervention [unlike the SuperMax...]

• CQR [Genuine original; 60 lbs; back-up anchor; mounted on custom chocks amidships on deck]
• We will also use the CQR rigged in an asymmetrical 2 anchor set-up
• Note: This is NOT 2 anchors in series...
• See this Practical Sailor article for details
• Revealing recent videos [Sep-2020] of genuine CQR in use
• I did the Coconut Milk Run long ago in a different boat with a genuine CQR and learned how to properly set and rely on one. They are much maligned compared to more recent designs, but still perform well in many bottom types if properly set. It will never achieve primary bower status, however (except possibly through attrition...)

The genuine CQR fits well on our bow

CQR normal position: stowed amidships in custom Starboard chocks

• Luke [AKA Fisherman; 100 lbs; stowed disassembled low against hull on custom chocks
• Uses: Storm/ rock/ coral/ extra deep anchoring

3 piece Luke [Fisherman] Anchor

• Fortress FX27 [Stern anchor; kedge]
• Fortress FX37 [Stern anchor; kedge; possible secondary bow anchor in all sand or mud bottoms in unidirectional anchoring situations only (e.g., Bahamian moor, etc.]

• Adjustable shank with two angles; 
• 45° for very soft, soupy mud
• 32° for sand
• NOTE: 32° works for everything; 45° only works in very soft mud [AKA ooze...]
• Selecting, assembling, and setting a Fortress Anchor
• Fortress recommends 6ft of chain for each 25 ft of depth, then rope
• HMPE line alternative to chain on Fortress anchors
• NOTE: Our experience [and that of others...] is Fortress anchors hold extremely well in sand or mud, but cannot be trusted to reliably and repeatably reset after a shift (60°-180°) in direction of pull under inclement conditions, so we only use one as a kedge, or in unidirectional pull anchoring situations only.
• Videos demonstrating unreliable reset after change in direction of pull

Windlass: [LightHouse 1501 with 2 chain gypsies (port and starboard) and 1 rope drum]

• 1000+ lb. continuous pull @80A, 12V DC; more if amperage is available
• 2 manual retrieval methods using a standard [or ratcheting] winch handle or our Milwaukee right angle (AKA arm breaker) drill
• 10,200 lb. manual kedge capability applying 35 lbs. force on a 10 in. winch handle
• Details about windlass refit with annotated installation photos
• Anchor Locker Design Details
• We have a portable electric winch driver as back-up for the windlass [and use on any winch as needed]

Anchor Rode and Tackle:

• Bow: [to windlass]
• Primary Anchor [Starboard side]: 
• 360 ft of 5/16 in. [8 mm] grade 43 [G4] chain spliced to 200 ft of 5/8" [16mm] 12 plait polyester [Samson Tenex]

Tapered 12 strand chain splice to a short length of 5/16" grade 43 chain- for connecting to a double-clevis [below]. [Here is a splice tutorial by a fellow cruiser.] Now we splice directly to the double-clevis pin so the pin can be changed out if it rusts.

• We use a forged, galvanized double-clevis to attach the rope rode [warp] to the chain [and to connect different lengths of chain together]: 

• This makes the annual reversing of the chain [end-for-end] an easier task as we don't have to re-splice the [rarely if ever used] rope to the new chain end each time. 
• And these double-clevises traverse our windlass chain gypsy under load just fine- especially when used for a chain-to-chain connection

  See: Anchor Chain Splicing Considerations for additional details, and a 10 second video of a double clevis traversing our gypsy under load

• How are our rodes are marked for depth? 
• See our scope calculator
• Chain hooks [2- 1 for each anchor] on 3-strand nylon line to both bow cleats
• Chain stopper
• Notes about the warp [rope] portion of our anchor rodes:
• Sizing: we went a little larger than matching tensile strength with the chain might indicate [we chose 5/8” vs minimum 1/2” that slightly exceeds the ultimate breaking strength of our 5/16” G43 chain] because:
• larger as a hedge against chafe
• for more comfortable manually handling [free hauling, and rope drum assist on windlass], 
• because our 5/16” ANSI gypsies pull 5/8” pretty well- if necessary 
• e.g., if we sustained injuries that prevent use of both hands/arms for rope handling, etc.
• We still affix a bridle to warp [rope rode; use Prusik knot] ] for 3 reasons:  
• Eliminate chafe on warp
• Keep any ground tackle loads off of the bow sprit [which could take it, but why do that?]  
• Avoid chafing on the bobstay
• An [adequate length] bridle avoids bearing against the bobstay when the boat yaws under strain at anchor
• Usage:
• The warp portion of our primary bower is for  ‘Hail-Mary’ [desperate] use cases, and therefore still new and un-deployed
• Therefore it is kept tied with break-away twine high in the anchor locker- away from being ground and dirty under the chain pile- but still ready to deploy
• Back-up Anchor [Port side]: 
• 190 ft. of 5/16 in. [8 mm] grade 43 chain spliced to 220 ft of 3/4 in. 3-strand nylon rode [To be Replaced with 5/8" [16mm] 12 plait polyester in near future; Spool of line onboard- see Planned changes, below...]
• Chain stopper
• Planned Changes in Future: 
• Rope [warp] portions of both bow anchor rodes [2] will be have been replaced with ~200 ft each, 5/8 in.[16mm] 12 plait polyester [Samson Tenex; 600 ft. spool on hand...]
• When our chain is due for replacement [hopefully several years- and several regalvanizings- away...] we may very well switch to grade 70 [G7] chain [heat treated G4...] 
• Update: Dec-2023: I have been contemplating splitting my 9 year old main bower chain [360’] in half and joining the two previous ends to become the new middle; thereby exposing the best [least worn] galvanizing at the [new] ends of the chain to try and eek out a few more years…
• The devil is in finding strong enough fasteners to use with G7 chain. [Two manufacturers will add oversized links at each end, but they won't heat treat them like the rest of the chain, so they are only as strong as what we have now; G4...]
• The Crosby G209A grade B shackles we now use [SWL 4400 lbs] would still be stronger than 5/16 inch G70 chain...
• One option is to use connectors from the lifting industry:
• Maggi's purpose modified Rud end-link
• MANILLE OMEGA Grade 70 galvanized shackle 
• Best option so far since it is galvanized and doesn't require a 2nd shackle to attach anchor and chain
• However, it has no provision for safety wiring
• Omega-Link. [Grade 80 or 100; Galvanized not yet found as of Nov-2023]
• Practical Sailor article which includes options for G7 chain connectors
• Can G7 be regalvanized without being weakened by the process? 
• Yes, per the results of testing by Practical Sailor

• Anchor bridle: 80 ft. 5/8 in. 3-strand nylon
• Details about use and techniques
• Practical Sailor article Mar-2016 about sizing
• Attached to chain using one of the following methods: [more details and photos]
• Dyneema webbing climbing loop Prusik hitched to middle of bridle line
• This keeps the bridle attachment point from sliding
• Secure climbing webbing loop to chain one of the following ways:[Need to add photos]
• Pass loop through chain link, then loop again and tie back to bridle using an Icicle hitch OR
• Loop in webbing attached to chain with soft shackle OR
• Dogbone [put loop through a chain link]
• Attach middle of bridle to anchor chain using a Prusik knot
• Holds if one side of bridle releases [unlike a cow-hitch]
• See Practical Sailor article on this topic
• We may experiment with either a Klemheist or Icicle hitch in the future. [Easier to tie/untie in middle of a long bridle, but may not hold if one leg breaks.]
• Soft shackles or double loop pendant [made from Dynema] will also work
• Slotted Stainless Steel Chain Plate for 2 line bridle
• Mantus Chain Hook [SS Devil's Claw]
• Mantus Snubber Pendant [New Sep-2017; looks interesting]

• Shackles: We only use forged, load rated, grade B shackles [Grade B is 2x as strong as Grade A...] that can be proof tested if desired [required for overhead lift uses]

Our main bower anchor/chain connection: 

5/16" G43 ACCO chain; 7/16" Crosby G209A shackle; 45KG [99lb] Spade S180 anchor

[Note the figure-8 monel wire seizing on the shackle pin- with the twisted tails wrapped around center of figure-8. This helps temporarily maintain the integrity of the seizing should a single strand break...]

• We typically use USA made Crosby brand [grade B, load rated forged alloy steel shackle and pin] shackles and chain connectors
• There are also other credible manufacturers of forged, load rated, alloy pin chain connectors [See Practical Sailor articles at the end of this section]
• The SWL [Suggested Working Load] of shackles must at least equal the SWL of the Chain 
• We chose 5/16 in. [8 mm] grade 43 [G4] chain = 3,900 lbs. SWL 
• Notes: 
• SWL on G4 chain is 1/3rd breaking strength; 1/4th on G7 chain
• Weight to strength ratio of 5/16” G4 chain is very close to both 3/8” and 1/2” G4 chain
• Here is a good article which also touches on strength to weight ratio of chains of the size we might use…
• Here are the Crosby G209A galvanized anchor shackles we use [a 1/2 in. pin fits 5/16 in. G4 chain; SWL = 4,400 lbs.]   
• Crosby Grade B shackles are rated in Metric tons @ 4.5:1 safety factor
• This means the 2 Ton rating embossed on the shackle equals 4,409 lbs SWL @ 4.5:1 safety factor; even stronger than Grade 70 chain
• Here is a Titan forged alloy shackle we also keep in hand in case we cannot find Crosby.
• I prefer the bolt type of anchor shackles [Class 3] that have a nut and cotter pin [eliminating mousing safety wire through the pin eye...] but they are sometimes more difficult to source, and the pins are not always galvanized
• Don't use cheap, non-forged shackles unless you want them to be the weak link in your ground tackle...
• Additional reading about anchor shackles: 
• Different types of shackles
• Anchor shackle testing [part 3] [Practical Sailor]
• Tips on Choosing and Sizing Anchor Shackles [Practical Sailor]

• Swivels: None installed; We haven't found the need, and don't have the desire...
• This video demonstrates why we don't need one 
• If you are in a hurry, fast forward to the 18:06 minute mark
• We do have two each 5/16 in. and 5/8 in. chain size; new, older [25+ years] SS Kong swivels on hand for unique circumstances like hurricanes [e.g., 3+ independent anchors in circle pattern to swivel, then single chain to boat from swivel; semi-permanent moorings; etc.]
• Related Practical Sailor articles of note: 
• How well do swivels reduce twist?
• Stopping anchor chain twist

• Chain connectors: Can chain be spliced?  Yes, but be careful what [and how] you use to connect the chain pieces together. 
• Brief Practical Sailor article: Reliable Chain Connections
• Here is one account [from a very credible source] of a forged, high quality forged connecting link [C-link] that catastrophically failed after years of service [at rest- not under load...] Includes proven techniques to greatly reduce chances of failure. [Gluing— in addition to peening— the C-Link with 3M 5200 would have helped prevent the above mishap]
• We prefer to use a forged double clevis [H-link] instead because they match the G4 chain working load [forged C-Links are ~30% weaker than the G4 chain...] are quick to install and remove, and they traverse our windlass chain gypsy under load just fine... 
• See: Anchor Chain Splicing Considerations for additional details, and a 10 second video of a double clevis traversing our gypsy under load
• We also use a forged double-clevis to attach the rope rode to the end of the chain rode. This makes reversing of the chain an easier task as we don't have to re-splice the [rarely if ever used] rope to the new chain end each time. 

• Spare anchor rodes in mesh anchor bags:
• 4- 3/8 in. BBB chain x 40 ft. spliced to 300 ft of 3/4 in. three-strand nylon
• Misc lengths and diameters of nylon 3-strand, and 5/16 in. and 3/8 in. chain

• Dinghy:
• 10 lb. collapsable grappling hook with 200 ft. of 3/8 in. nylon 3-strand rode; snatch block for shore retrieval
• Future: We need better dinghy anchor for non-beach setting situations Currently the quick assemble Mantus dinghy anchor is our first choice, with a small Danforth style anchor in 2nd place... [Based upon recent 3rd party testing; see Additional Resources, below. ]
• 2 ft. diameter sea anchor/drogue 
• Also used on boat's primary anchor chain- just below the waterline on the tensioned part of the chain rode- to dampen horsing at anchor in high wind conditions [vs. setting a Hammerlock Moor]
• Anchor Buddy elastic rode [50ft of stretch.] 
• Also need separate line from dinghy to shore for retrieval
• Elastic Anchor Buddy pulls the dink back to the anchor- away from the beach- after passengers have disembarked
• This helps prevent [the heavy RIB w/ outboard] from grounding when the tide goes out... 
• Separate shore line is made fast on shore [e.g., tree, rock, another small anchor, etc.] for pulling dink back to the beach- and as a safety line [i.e., 2nd anchor rode...]
• It also helps pull the dink back to the anchor [once afloat] after the passengers reboard at the landing beach [so we don't have to paddle to water deep enough for lowering the outboard... Remember we admit to being inherently lazy...]

Shore Lines/Tackle: [AKA shorefasts; We try to avoid using, but some situations warrant...]

• Quickline Reel of heavy duty polyester strap rode mounted on stern rails
• Now available from the Ultra Anchor company with choice of lines and lengths
• Line reel for shoreline [holds 600+ ft. of 3/8 in. UHMP line]
• Line reels with interchangable spools 
• Something of interest but not yet tried; could be useful for stowing/retrieving shorelines, crab and shrimp trap lines, etc.
• 6- 100 ft. lengths of 3/8 in. bright colored Spectra line [14,000 lbs tensile] with soft eyes at both ends for cow hitching or soft shackling in series- stored in bags
• Shore lines can be cow hitched or soft shackled together at soft eyes to extend length
• Wait; doesn't cow-hitching weaken the lines? 
• Yes, but only ~15% according to Samson Ropes [page 33]
• Small, preferably brightly colored foam fishing net floats used to make line more visible when floating on [or hanging above] water when necessary
• Various lengths of chain 
• for securing shore fast to rocks/boulders
• Galvanized cable chokers with soft eyes [i.e., no thimbles] at both ends 
• for securing shore fast to rocks/boulders
• rocks can sometimes be lassoed from dinghy
• Heavy duty vehicle towing or lifting straps with eyes on both ends and tubular webbing
• for securing to the base of trees to help prevent damaging them
• How do we create stretchier, stronger lines in inclement conditions? [Especially useful for shorter shore lines to a quay or dock in surge or high wind conditions...]
• To increase stretch [and strength] in times past I have had success tightly twisting two lengths of 3-strand nylon [e.g., 1/2 inch] for each tie. That improves strength and give you a quick way to add some stretch if you have no alternatives at the moment... [One method is to secure the middle of a long enough length of 3-strand to the quay or use a Prusik knot [which holds even if one leg breaks- unlike a cow-hitch…] to the eye on your UHMWPE [stretch-less] shore line, then lead the 2 bitter ends to the boat as a single line. If secured to something rigid (vs another line), twist the two secured lines together from the boat as tight as you can and cleat it off as a single line. Repeat for the other shore ties.
• Related Resources- Shorefasts: 
• Blog post about our typical shorefast methodologies
• Attainable Adventure Cruising on Shorefasts [A subscription site, and well worth it to us...]

Storm Tackle:

• 24 ft. diameter Paratech sea anchor connected via very heavy duty SS swivel shackled to 600 ft. of 1-1/8 in. 12 strand Mega Braid [34,900 lbs. tensile]
• Blog post regarding deployment strategies
• 6 ft. diameter Delta Drogue with 200 ft. of 1-1/8 in. 12 strand Mega Braid [34,900 lbs. tensile]
• Future: Jordan Series Drogue
• Battle Testing a Jordan Series Drogue [Article in Attainable Adventure Cruising]

Anti-Chafe Gear:

• Chafe Pro Yacht Series [The best we have used in 30+ years]
• Dyneema Chafe Sleeve
• Oversized firehose [Great stuff, and cheap if you can obtain a small roll... Must be oversized so water and air can enter to help keep a working line cool in spunky conditions.]
• Related Practical Sailor article: Chafe Protection for Fiber Rodes

Communications while anchoring [How, and what we use and do...]


Additional Resources:

• Books: [There are many great books available. The following just happen to be the ones we find ourselves referencing the most.]

• Rigging Modern Anchors 
• Drew Frye; 2018; This is not a rehash of what has already been documented. It goes well beyond theory to practical application.

• The Complete Anchoring Handbook: Stay Put on Any Bottom in Any Weather
• By the late designer of the Spade anchor, Alain Poiraud
• Complete book of Anchoring and Mooring [I have used the 1st Ed. of this book for decades, and the 2nd Ed. is even better, although some techniques (e.g., kellets, heavy chain) have since been demonstrated as invalid...]
• Practical Sailor Anchoring eBook Series [Highly recommended]
• Creative Anchoring: Everything a Cruising Sailor needs to know about Anchoring and Anchor Gear
• Happy Hooking - the Art of Anchoring

• Online Resources:
• Anchoring and ground tackle; engineering and mechanics: [In no particular order...]
• Practical Sailor articles:  [subscription required]
• Anchoring and mooring
• Lateral Thinking
• Rope to chain splice test
• Rope Chafe Protection
• Brief technical overview of anchoring and ground tackle [Alain Fraysse]
• Anchors and Anchoring [Peter Smith- Rocna]
• Short Scope Anchoring in Deep Water [Like Alaska...]
• Challenging the chain catenary myth...
• Photos of anchors setting
• Videos of anchors setting [Very objective testing]
• Calculating scope can be very misleading... [Forum discussion]
• Drag Device Database [Storm Anchoring using Sea Anchors and Drogues]
• Jordan Series Drogue 
• Attainable Adventure Cruising 
• [Membership required; well worth the modest annual fee to us...]
• Related articles, blog posts and forum discussions: [This is a work in process and is not all inclusive. I will add to this list as I encounter useful, first-hand information...]
• Cox Engineering [Detailed chain info- among other topics]
• Welded Steel Chain Specs
• Anchor shackle specifications and testing 
• Tips on Choosing and Sizing Anchor Shackles
• Choosing anchor chain (and challenging myths)
• More on choosing chain- including strength to weight ratio
• The Right Rode [Essay about polyester vs nylon by Steve Dashew]
• Chafe Protection for Fiber
• Prolonging the Useful Life of Anchor Chain [Forum discussion]
• How to set a Bahamian moor
• Methods for reducing yawing at anchor [Good Old Boat article by Drew Frye]
• CQR 1st hand experiences
• Sleeping well at anchor [blog post]
• Lateral thinking and anchoring (including high latitudes) [Practical Sailor article]
• Our new best bower post
• Great discussion re: "100 pound anchor effect" on Cruiser's Forum
• When the windlass fails [blog post]
• Cleaning mud off the anchor chain [blog post]
• Battle Testing a Jordan Series Drogue 
• Choosing chain [and challenging the size myth...] 
• Anchor Chain Splicing Considerations [Blog post]
• Chain marking methods [Cruiser's Forum discussion...]
• We have decent success using plastic wire ties [zip ties]
• Paint must be sandblasted away before regalvanizing- adding considerably to the cost
• Calculators
• Catenary Calculator [way beyond the Pythagorean theorum...]
• Catenary Force Plot [Determine how much force is required to lift your chain off the seabed...] 
• Update Mar-2021: This link may have evaporated from the internet. I will leave it for now in case it reappears or is redirected in the future.
• Here it is in the WayBackMachine archive! 
• Anchor Scope Calculator [A spreadsheet we created and use to help mitigate mental mistakes during stressful anchoring situations]
• Excellent anchoring [engineering] calculator [including effects of bridles]
• Another excellent scope calculator- also available as a smartphone app

• Videos/ How-To/ Sources:
• Regalvanizing anchors and chain
• Soldering galvanization defects [rust spots]  
• Using Kapp Galvanite
• How chain is made
• How double braid rope is made
• Videos of anchors setting 
• This series of videos [100+] by a fellow cruiser will help answer most of your questions about which anchor[s] may be best for you...