Re: Home made anchor

He was reading a book about dock building. I would infer he wants to anchor
a floating dock. Lets make 16 100 lb rubber tire anchors place four on each
corner of a floating dock say 10' x 20'. Do you think it will anchor?

Some of y'all take this stuff (and perhaps yourselves) a little too
seriously don't you?

Ed

Goo'day,

Doesn't the very use of the word "anchor" mean that the anchor itself
needs to anchor itself to something?

How are you going to anchor the anchor if it's but a block of
something heavy?

Would that a block of something *would* anchor.   But of what value is
a block of something sitting on, say, sand, in a 40kt wind?    

If, though, the block had flukes to anchor it in place, then there's a
difference, and it might be of some use.    Even fluked anchors have
been known to drag in tide and wind - and that's what you're guarding
against - dragging.    The physical weight of the thing is far
outweighed by the ability to withstand something trying to move it
sideways, not vertically.....

Your only option in an anchor is the degree of "fluking" required the
locality/s you're going to want to anchor.    

You think I'm wrong?  Toss a block of concrete the same weight as a
fluked anchor over the side and see how far you drift/drag.....

Home made?  Waste of bloody time!    And a danger to all concerned...
especially to those striving to rescue you..

B.

There are lots of things to consider in an anchor - and you haven't given us
any idea of what it is you are trying to anchor, where, or under what
conditions.  But to look at just one consideration.  If you made a 1000 kg
anchor out of something with a density of say 2.0 ( mix of rubber and
concrete.), it would take a force of 500 kg to lift it vertically up.  If
you made it out of something with a density of 5.0  ( mix of steel and
concrete )  it would need a force of 800 kg to lift it vertically up.
Obviously boats don't usually try to lift anchors vertically up, they roll,
slide, dig into mud, get undermined by current   .........   So the
statement that mass alone does not make a good anchor is very much an
understatement.

DF

If it doesn't matter then I'm OK with that.
Thanks.

I know, are you talking about cement here?
Not quite sure you are meaning.

Leach out what?  Limestone?  So what?

Mass alone does not make a good anchor.

Hey all,

I read a while back in a book about building docks
a method for making an anchor:  pour about 100 lbs.
(or more?) of cement into a smallish tire.  Sink a
U-shaped piece of metal into it to attach the chain.

Now, my question:  is this an environmentally sound
anchor?  Doesn't cement leach out or something under
water?  And, wouldn't the tire decompose over time
under water?  (I'm talking about fresh water in
upstate NY, by the way).

I'd think making some other disk-shapped mold would
be a better way to go, if one is using cement, just
wondering what anyone else thought.

Thanks,

Julien