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Want to know why dock mounting anchor systems fail?

Google search for "cable shock load" and "impact load".

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Dock Springs

Dock Springs protect floating boat docks from storm and wake damage by absorbing the impact load on your anchoring system.

All floating docks secured to the shore with cables need and will benefit from a dampener to mitigate shock loading on the anchor system.  Dock springs are the most effective dampener you can get. 

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Dock spring fabrication
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DOCKS LIVE LONGER WITH DOCK SPRINGS

What are dock springs?

Think of the old screen door at grandma's house.  It had a "wind chain" with a spring thingy on the end of it.  The spring on the chain caught the door at its widest open position and arrested its movement when the wind blew it open, protecting the door and keeping the little chain and its mounting screws intact.  

Dock springs work the same way, just on a much, much larger scale.  

Dock springs are installed on your cables and dampen the forces created by the movement of your dock.  You dock's subtle movements create shock loads that over time work to loosen your anchors.  In a substantial storm, dock springs absorb large loads that would otherwise become large shock loads and impact loads that would break your dock loose.  See the "what is shock loading" page for more info on how shock and impact load relates to your dock.

Here are a few recent installs I have completed here on my home lake.

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What are Dock Springs? How are they made?  Why do we need them?  How can I get them?
Here are 4 short videos that will answer these questions.

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Making Dock Springs

FOP Range Inc.
Making Dock Springs
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Making Dock Springs
04:51
Play Video

Making Dock Springs

Birth of a Dock Spring
03:34
Play Video

Birth of a Dock Spring

Spring at work 2
01:28
Play Video

Spring at work 2

How dock springs work.

Each dock has weaknesses that may become a point of failure under stress.  When the wind picks up, you can see your dock move as the velocity of the wind picks up and drops off.  When a wake from a boat hits your dock, it moves against its anchors.  Each time its movement is stopped by a cable, winch, and anchor.  

 

At the moment it reaches the point where any slack in the cable is taken up, the kinetic energy from its entire weight in motion plus the forces from wind, wake, and current pushing on it are deposited on your anchoring hardware.  This energy is a shock load that is applied to your cable and an impact load that is applied to your hardware in that fraction of a second.  Its getting pounded.  

 

A dock spring on your cable is a dampener that arrests momentum and spreads the loading of your cable, winch and anchor over time, mitigating the shock and impact load.  The only way to reduce shock and impact load is to increase the time it loads your system.  Dock Springs are load dampeners that do that.

What is shock and impact loading?
See the "What is Shock Loading" page here.  I got a little nerdy and worked out a few shock load and impact load problems to explain what it is, how it affects our docks, and what you can to do to fix it.  There are mathematical formulas that will show you the forces involved when a dock moves.  I used the round number of 10,000 lbs. dock weight in my examples but that is on the light side.  The two boats on my dock weigh more than 10,000 lbs.  The forces involved in stopping your dock's movement are tremendous. 

Why do I need Dock Springs?

A Dock Spring on each of your cables will greatly reduce the shock and impact loading of your hardware. 

 

Ever go camping in a tent?  How did you get the tent pegs out of the ground when it was time to go home?  You tap on them from the side with the hammer you used to install them.  They will then come out easily.  
 

A moving dock is a lot like a huge hammer, beating against its anchors.  Anchors become loose and get pulled out of the ground, winch gears strip and mounting bolts shear, welds break, metal tubing fatigues from work hardening and then cracks, cable clamps slip and let the cable go.  

 

Dock Springs absorb this shock load and spreads the impact on your anchor system over time.  A Dock Spring takes several seconds to compress, absorbing the energy of your dock's momentum, and spreading the loading of your hardware over time.  See the "What is Shock Loading" page to learn why time is so important.
 

The choice to add something that arrests this momentum, protecting the rest of the anchor system, is a really good idea.  Its an investment in your dock.  We all know what happens when a dock breaks loose and it will be expensive.  

Dock anchor winch damaged by storm
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When to get Dock Springs
The best time to get a set is before you need them.  If the last storm knocked your dock loose and you are going to have to work on it, why not upgrade what you have with something that will reduce the risk of it breaking again? 

Most of us think about our the safety of our docks when we hear the weather forcast has wind gusts or severe thunderstorms in it. 

So far, most of my customers have 2 things in common...

One, they have had to repair their dock more than once due to anchor system failures.  A dampener on your dock cable will effectively mitigate shock and impact loading that causes failure and damage. 

And second, most work in or have retired from an engineering related job.  They have the knowledge and experience to understand and see that Dock Springs are the answer to this problem.

How much are they?
The spring set that most of you need is priced at $500 for the pair.  I throw in the 3/4" heavy duty shackles so you won't have to hunt up anything to get your set installed. 

Why are they so much? 
Three reasons...

  1.  I only use new components in the fabrication of your springs.  Sure, scrap yard parts can be sourced but most likely will result in inconsistent performance.  A tired spring that has already seen 100,000+ miles under a truck will not be as strong or reliable as a new one.  New parts cost more.

  2. There is a fair amount of skilled labor involved in fabricating a forged steel dock spring assembly.  The video above shows the basic process but has been sped up 30X.  It is not created at a factory in China by robots or child labor.  There is also the equipment, tools, expendables, gas, paint, the place to make them, insurance, business licenses, advertising, an accountant, software, computer, internet, utilities, truck and trailer to haul steel used, fuel, and (I'm sure I've left things out) other stuff needed that I pay for to be able to produce a set of springs for you.

  3. I'm it.  There is no other place on the planet that I can find that produces a captured, forged steel, dock movement dampening spring assembly for your cables.  I've done the research to determine the proper components.  Compression rate, coil wire diameter, outside diameter, overall relaxed length, the number of active coils, the coil body design, the coil wire termination method, and coil spacing all matter in determining a proper spring for a Dock Spring application.  The components used in the dock springs I produce are more than up to the task of protecting your dock's cables and anchoring system.  

How do I get a set?

Hit the SHOP button above.  It will take you to the online store on this website where you can select the set you need.  I will ship the next day.   If you are in an area served by a Dock Spring distributor, contact them to get a set locally and set up an installation.  See Sales and Installation Partners page.

Free shipping!
Use coupon code "SHIP FREE" at checkout to receive free shipping on your order.  Free shipping will be available for the 1st 100 sets that leave here.  If you are on my home lake, Lewis Smith lake in Alabama, I can bring them to you and will eat your sales tax.  I can also do Dock Spring installs if you are on my lake.  

Need more info about Dock Springs?
Take a look at the Dock Springs Info page and Frequently Asked Questions pageAs I field questions on Facebook and over the phone, I will add them to the FAQ page.

 

You can call me.  We will have a talk about what you have and what you need.  I will take your order and send them to you.  The number is 205-966-2137.  If you are local to the Smith Lake area, stop by my shop and check them out for yourself.  There is a google map link to my shop below.

I've gotten a few comments that I can share with you. 
A dampener system on your anchor cables is a very good thing.

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Grigsby Enterprises LLC - Dock Springs
945 County Road 335

Crane Hill, AL 35053
205-966-2137
jongrigsby@docksprings.com

docksprings.com © 2024 by Grigsby Enterprises LLC - Dock Springs  

If you have any questions, please call 205-966-2137.  We can figure it out.

You can also reach me on Facebook messenger.

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