On Feb 13, 6:33 am, "Dan Listermann" wrote:
"Two meter troll" wrote in ...
On Feb 12, 10:54 am, "Dan Listermann" wrote:

I want to build two docks, one permanent and a floating one. The floating
one will be supported by 15 gallon plastic drums. I can get 55 gallon, but
for a 4 x 8 dock, I worry about center of gravity issues.

The permanent one will be built of 55 gallon drums filled with dirt. Any
issues to look out for?

and again build it so the barrels can fall out when they get full of
water or your dock will sink lower and lower.
those plastic barrels will eventually fill all you need them to do is
push up so it costs you nothing to make the darn thing safer

Can you expand on this? I am not sure that I follow you here.

when you build the floating dock you are going to have a bit of free
board. when plastic barrels fill with water they just barely clear the
surface. if you fix them to your floating dock they will pull the dock
down as they fill. so you make the dock in such a way that the barrels
can sink without pulling the dock down.

Anecdote: here in oregon we get spring floods that bring root balls,
sunken trees, and other stuff down the river. floating docks made with
plastic barrels are popular here. if the barrels on the edge of the
dock get hit by a submerged root ball it can put a hole in the barrel
causing it to fill with water and sink. if the barrel is fixed to the
dock this will pull down the edge of the dock a bit. then the intact
barrels are closer to the stuff rolling down the river and more likely
to get punctured.

if you do not strap the barrels to the dock then the punctured barrel
sinks out from under the dock. this may cut down on the flotation of
the dock but it wont have the effect of pulling your dock down.

"mmc" wrote in message
g.com...

"Dan Listermann" wrote in message
...
I want to build two docks, one permanent and a floating one. The floating
one will be supported by 15 gallon plastic drums. I can get 55 gallon,
but for a 4 x 8 dock, I worry about center of gravity issues.

The permanent one will be built of 55 gallon drums filled with dirt. Any
issues to look out for?

The 55 gallon drums filled with dirt may float because of the air trapped
in the dirt. If soaked after positioning and filling, they still won't
weigh much. Concrete blocks are something like 30-40% thier (in air)
weight when submerged.
You can "jet" pilings in with a trash pump. Last time I rented one was a
couple years ago and it cost me $25/day. In a day you can jet around a
bazillion pilings. Four of us non-professional jetted in 40 pilings in a
couple of hours.
I use an old pontoon platform for my dock but I'm interested in the details
of how you "jet" a piling in and exactly what a "trash pump" is. I have
need to put in a permanent short pier at the edge of the bank to support
the land side of my ramps to the dock. I had piers supported by 2 inch
pipes driven into the shore bottom but last years flood lifted the pier and
the pipes right out of the ground and bent everything to hell. I figure 4
inch well pipe would hold up but the only contractor on the river with the
equipment capable of driving them is apparently not interested in any new
business. I tried for 3 years to get him to give me a quote on some rip
rap or vinyl wall (his advertised business) but he doesn't seem interested.
I had $26,000 in my budget but I didn't really want to tell him that up
front.

Tom G.

"Dan Listermann" wrote in message
...
I want to build two docks, one permanent and a floating one. The floating
one will be supported by 15 gallon plastic drums. I can get 55 gallon,
but
for a 4 x 8 dock, I worry about center of gravity issues.

The permanent one will be built of 55 gallon drums filled with dirt. Any
issues to look out for?

Get a Copy of:

"The Dock Manual" by Max Burns
Storey Publishing Co.
1-800-793-9396

Library of Congress info

ISBN-1-58017-098-6(pbk)

Story Books, 210 MASS MoCA Way, North Adams MA, 01247


Lots of good info, sources, plans pitfalls etc.

Well worth the money

their website is

www.storey.com

KG

On Fri, 13 Feb 2009 15:22:53 -0800 (PST), Two meter troll
wrote:

if you do not strap the barrels to the dock then the punctured barrel
sinks out from under the dock. this may cut down on the flotation of
the dock but it wont have the effect of pulling your dock down.

The water in the barrel does not pull anything down. The full weight
in water is only a few pounds, that of the empty barrel. The lack of
bouyancy will cause that part of the dock to sink. It's not a downward
pull, it's the loss of an upward push. Water in water weighs nothing.

Casady

"Tom G" wrote in message
...

"mmc" wrote in message
g.com...

"Dan Listermann" wrote in message
...
I want to build two docks, one permanent and a floating one. The
floating one will be supported by 15 gallon plastic drums. I can get 55
gallon, but for a 4 x 8 dock, I worry about center of gravity issues.

The permanent one will be built of 55 gallon drums filled with dirt.
Any issues to look out for?

The 55 gallon drums filled with dirt may float because of the air trapped
in the dirt. If soaked after positioning and filling, they still won't
weigh much. Concrete blocks are something like 30-40% thier (in air)
weight when submerged.
You can "jet" pilings in with a trash pump. Last time I rented one was a
couple years ago and it cost me $25/day. In a day you can jet around a
bazillion pilings. Four of us non-professional jetted in 40 pilings in a
couple of hours.
I use an old pontoon platform for my dock but I'm interested in the
details of how you "jet" a piling in and exactly what a "trash pump" is.
I have need to put in a permanent short pier at the edge of the bank to
support the land side of my ramps to the dock. I had piers supported by 2
inch pipes driven into the shore bottom but last years flood lifted the
pier and the pipes right out of the ground and bent everything to hell. I
figure 4 inch well pipe would hold up but the only contractor on the river
with the equipment capable of driving them is apparently not interested in
any new business. I tried for 3 years to get him to give me a quote on
some rip rap or vinyl wall (his advertised business) but he doesn't seem
interested. I had $26,000 in my budget but I didn't really want to tell
him that up front.

Tom G.

Tom,
Check this link:
http://www.wikihow.com/Install-Posts...a-Dock-or-Pier
Good description and saved me the time of writing it.
The dock work I've helped with has been in Florida's Indian River with sand
bottom. I don't know how well this will work in other environments.
We used a rule of thumb of 1/3 the piling length and a minimum of 4 feet
buried. One of the docks I helped with got destroyed by a big storm fetch,
but the pilings were still standing.
The rental places here have pumps set up just for this with the pipe already
set up and pinched. All we did was plunge the pipe length (6') (1-3" water
depth) all the way down a couple of times, then stand the piling up and let
it sink in the hole. One guy holds it plumb while the other jets around it a
little, guy one keeps holding it plumb for a few minutes until the sand
settles. Doesn't take long.

Top posted because this is getting long, but I don't want to loose the
thread.

OK Don,

If the plan to use debris filled drums places those drums on soil, you
may have a problem with the river at crest scouring under the drums.

Someone suggested jetting in poles with a pump and a pipe. This will
have no scour issue.

Both of these will have trouble if they are in the frozen river when the
level rises. Ice is tenacious and it will effectively bond to just
about anything. If it lifts the drums the river will scour underneath
them. It can pull wood or steel pilings out just about as easily. But,
if the river rarely freezes and doesn't change level when it does, that
leave that out of your consideration.

This is my set of suggestions for you case. Free advice is often not
worth the cost, but this is based on experience and may at least give
you some good ideas to work with.

If you jet in 4*4 treated poles, you can clamp cross-bars to them so the
dock elevation can be adjusted easily or drill and bolt which is faster
assembly. The decking can be made from 2*8 runners with 1*6 decking.
Make the pieces so that they can be bolted end to end after being
assembled on the bank. Use hot galvanized nails or deck screws to hold
the decking on. (Boards will crack with age so be ready to replace a
couple a year.)

Build this dock out as far in the river as you want to get. You can use
it to moor the floater.

On the downstream side, jet in an extra post so two posts are a foot and
a half apart. You can use lag screws to put on the rungs for the ladder
to get to the floating dock when the water is low. The ladder can not
be the mooring for the floater.

Moor you 4*8 floater to the posts by running a chain through a piece of
galvanized pipe at each end's mooring post.

You are right that 50 gal drums under a 4*8 deck does not make for a
very stable floater. The drum center ends up being just too far from
the edge you want to stand on. (Sound like a BTDT?)

If you can get the 15 gal jugs, they will be quite adequate. It you
mount then so the opening is up and leave some means to get at the plug.
You should have 10 or 12 of these under the floater, and one of them
will at some time begin taking on water. If you can get at the plug,
you can pump it out to get through the season - or - fill it with water
so it can be pulled out from under the deck and replaced with another
water filled can that is not leaking that you then pump dry so you
flotation is restored.

If something here doesn't make sense, it is probably because I forgot to
include some (hopefully non-critical) step.

Good Luck

Matt Colie



Dan Listermann wrote:
"Matt Colie" wrote in message
...
Dan Listermann wrote:
"Two meter troll" wrote in message
...
On Feb 12, 10:54 am, "Dan Listermann" wrote:
I want to build two docks, one permanent and a floating one. The
floating
one will be supported by 15 gallon plastic drums. I can get 55 gallon,
but
for a 4 x 8 dock, I worry about center of gravity issues.

The permanent one will be built of 55 gallon drums filled with dirt. Any
issues to look out for?
and again build it so the barrels can fall out when they get full of
water or your dock will sink lower and lower.
those plastic barrels will eventually fill all you need them to do is
push up so it costs you nothing to make the darn thing safer

Can you expand on this? I am not sure that I follow you here.
Dan,
With three waterfront houses in the family, we have assembled more than a
few docks.
Is this tidal water ?
Does it freeze ?
Is it open water ?
Is there some kind of boat wake control ?

When I have some answers, I will write about building floating docks and
some very specific things to not do...

It is on a river that only occasionally freezes. The last time it froze all
the way across was 1985. The river's level is quite variable and the
current can be swift. It falls 6 feet in a mile. Our side of the river is
opposite the main channel. It's level in summer is not much to the point
that motors are not normally used. It is Indiana's Whitewater River just up
stream from Harrison.

"mmc" wrote in message
ng.com...

"Tom G" wrote in message
...

"mmc" wrote in message
g.com...

"Dan Listermann" wrote in message
...
I want to build two docks, one permanent and a floating one. The
floating one will be supported by 15 gallon plastic drums. I can get 55
gallon, but for a 4 x 8 dock, I worry about center of gravity issues.

The permanent one will be built of 55 gallon drums filled with dirt.
Any issues to look out for?

The 55 gallon drums filled with dirt may float because of the air
trapped in the dirt. If soaked after positioning and filling, they still
won't weigh much. Concrete blocks are something like 30-40% thier (in
air) weight when submerged.
You can "jet" pilings in with a trash pump. Last time I rented one was a
couple years ago and it cost me $25/day. In a day you can jet around a
bazillion pilings. Four of us non-professional jetted in 40 pilings in a
couple of hours.
I use an old pontoon platform for my dock but I'm interested in the
details of how you "jet" a piling in and exactly what a "trash pump" is.
I have need to put in a permanent short pier at the edge of the bank to
support the land side of my ramps to the dock. I had piers supported by
2 inch pipes driven into the shore bottom but last years flood lifted the
pier and the pipes right out of the ground and bent everything to hell.
I figure 4 inch well pipe would hold up but the only contractor on the
river with the equipment capable of driving them is apparently not
interested in any new business. I tried for 3 years to get him to give
me a quote on some rip rap or vinyl wall (his advertised business) but he
doesn't seem interested. I had $26,000 in my budget but I didn't really
want to tell him that up front.

Tom G.

Tom,
Check this link:
http://www.wikihow.com/Install-Posts...a-Dock-or-Pier
Good description and saved me the time of writing it.
The dock work I've helped with has been in Florida's Indian River with
sand bottom. I don't know how well this will work in other environments.
We used a rule of thumb of 1/3 the piling length and a minimum of 4 feet
buried. One of the docks I helped with got destroyed by a big storm fetch,
but the pilings were still standing.
The rental places here have pumps set up just for this with the pipe
already set up and pinched. All we did was plunge the pipe length (6')
(1-3" water depth) all the way down a couple of times, then stand the
piling up and let it sink in the hole. One guy holds it plumb while the
other jets around it a little, guy one keeps holding it plumb for a few
minutes until the sand settles. Doesn't take long.
Thanks...answers my questions. I think it just might work. River bottom is
mostly sand with some small gravel mixed in. Pilings would be above the
edge of the water's edge except at flood level and then no ice involved.
Intend to set an aluminum pier section on top that can be lifted off during
the off season. I had a heavy wooden pier section but the water was
unusually high this last year and it floated it and the steel pipes up and
twisted everything beyond saving.

Tom G.

Dan Listermann wrote:
I want to build two docks, one permanent and a floating one. The floating
one will be supported by 15 gallon plastic drums. I can get 55 gallon, but
for a 4 x 8 dock, I worry about center of gravity issues.

The permanent one will be built of 55 gallon drums filled with dirt. Any
issues to look out for?


Might you consider using 55 gal drums instead of 15 gallon drums, and
part fill the big drums with 10 gallons of dirt of specific gravity 4
( = 4 times as dense as water...)

That would put the CofG lower than the 15 gal drums.....

Brian W

Brian Whatcott wrote in
:

Dan Listermann wrote:
I want to build two docks, one permanent and a floating one. The
floating one will be supported by 15 gallon plastic drums. I can get
55 gallon, but for a 4 x 8 dock, I worry about center of gravity
issues.

The permanent one will be built of 55 gallon drums filled with dirt.
Any issues to look out for?


Might you consider using 55 gal drums instead of 15 gallon drums, and
part fill the big drums with 10 gallons of dirt of specific gravity 4
( = 4 times as dense as water...)

That would put the CofG lower than the 15 gal drums.....

Brian W


Where do you get dirt that dense? Most rock is around 2.5 to 2.7; green
foundry sand is around 3, and that is about as dense as you get without
going to something like pig iron.

Jim Willemin wrote:
Brian Whatcott wrote in
:

Dan Listermann wrote:
I want to build two docks, one permanent and a floating one. The
floating one will be supported by 15 gallon plastic drums. I can get
55 gallon, but for a 4 x 8 dock, I worry about center of gravity
issues.

The permanent one will be built of 55 gallon drums filled with dirt.
Any issues to look out for?


Might you consider using 55 gal drums instead of 15 gallon drums, and
part fill the big drums with 10 gallons of dirt of specific gravity 4
( = 4 times as dense as water...)

That would put the CofG lower than the 15 gal drums.....

Brian W


Where do you get dirt that dense? Most rock is around 2.5 to 2.7; green
foundry sand is around 3, and that is about as dense as you get without
going to something like pig iron.

Hehe...look: someone paying attention! If I said "fill the drum to leave
15 gal worth of buoyancy", would that be better?

:-)

Brian W