Wayne.B wrote:
On Tue, 16 Oct 2018 14:12:01 -0400, John H.
wrote:

We've had a lot of rain.

I bought a new post for the mailbox. Had Ms. Utility out to mark the
underground lines. The new post
needs to be back from the curb 24" to allow for 6" of space from the
street and 18" of mailbox. I
had a rod marking the location I wanted to dig. When I went out to look
this morning, the utility
marker had put a yellow line right through the spot I wanted for the
post. The gas line. Now why the
hell, given the USPS requirements, would the gas company put their damn
line right there? Jeeez!

But, here's the quandary. I need a hole 24" deep for the post. About 15"
down, I hit the new water
table from all the damn rain we've been having. Keep digging. Now I'm
down 24", but the bottom 8-9"
if full of water. I'm thinking if I dump a bag of sacrete down there
it'll just become soup. Ditto
with putting dirt down there. As the post and the mailbox are quite
heavy, it's got to be set pretty
firmly.

****.

===

Hydraulic Cement may be your friend:

https://www.thebalancesmb.com/what-is-hydraulic-cement-uses-and-how-to-apply-845076




One great advantage is it expands a tiny bit, so will lock into undercut
surfaces.

On Tue, 16 Oct 2018 18:46:29 -0400, wrote:

On Tue, 16 Oct 2018 17:05:23 -0400, John H.
wrote:

On Tue, 16 Oct 2018 16:52:44 -0400, "Mr. Luddite" wrote:

On 10/16/2018 3:36 PM, John H. wrote:
On Tue, 16 Oct 2018 14:26:27 -0400, wrote:

On Tue, 16 Oct 2018 14:12:01 -0400, John H.
wrote:

We've had a lot of rain.

I bought a new post for the mailbox. Had Ms. Utility out to mark the underground lines. The new post
needs to be back from the curb 24" to allow for 6" of space from the street and 18" of mailbox. I
had a rod marking the location I wanted to dig. When I went out to look this morning, the utility
marker had put a yellow line right through the spot I wanted for the post. The gas line. Now why the
hell, given the USPS requirements, would the gas company put their damn line right there? Jeeez!

But, here's the quandary. I need a hole 24" deep for the post. About 15" down, I hit the new water
table from all the damn rain we've been having. Keep digging. Now I'm down 24", but the bottom 8-9"
if full of water. I'm thinking if I dump a bag of sacrete down there it'll just become soup. Ditto
with putting dirt down there. As the post and the mailbox are quite heavy, it's got to be set pretty
firmly.

****.

You can either use a tremie (a pipe that goes to the bottom and allows
the concrete to get there unmolested) or just dump it in and get on
with your life.
Considering mail box posts are not bridge pylons, I would just dump it
in (mixed pretty stiff). Dump it in large quantities at the same time
and it will just displace the water and be fine. Sack concrete is
typically 3500 psi gravel mix so even if you lost 90% of the strength,
it would still hold a mailbox post until the post snapped.
The reality is I doubt you lose 25% and less than that if it all goes
in one slug. They place concrete under water all the time.

Yes, concrete placed under water is no problem. But, sacrete isn't concrete 'til it sets. That, I
fear, is the problem. Maybe I'll just dump two bags of sacrete in there - unmixed.



I mentioned in another post ... that's what I did in Florida installing
new posts for a horse pasture. Holes I dug were half filled with water.
It was Sacrete. Poured it in the hole dry, straight from the bag
around the post and it hardened and worked just fine.

I read it. How long did it take to set? The post I'm putting in is this one:

https://www.lowes.com/pd/Cedar-Produ...-Post/50195217

I don't want to stand there for several hours holding it up. And I don't want to pound nails in it
to brace it with 1X4's

You are over thinking this. If you mix the concrete up to about the
consistency of cookie dough and dump it in the hole in bug chunks, the
water will come right out and the stuff at the bottom will be plenty
stiff enough to hold up the post without bracing.
Pouring it in water, while it is dry is the worst thing you could do
because the aggregate will fall out of the cement that is lighter. I
still think for just setting a mailbox post it would be OK.
A don't even bother with concrete for my mailbox. I just backfill with
dirt and tamp it in. That way replacing it when it gets hit is not so
tough.
Maybe Harry will drop you off an empty kitty litter bucket. Those are
just right for this sort of thing since you can more easily hit an 8"
hole with a slug of concrete.

If you really want to get pedantic about this, how long did it take
for the ground water to fill the hole. If you dropped a bilge pump in
there and pumped it out, could you get the post in there and get a
foot of concrete in there before it filled back up?


The water was filling as I was digging. I wouldn't dump the mix on top of the water. I still like
the idea of mixing the sacrete in a wheel barrow, and dropping it into the plastic bag with the post
inside. No extra water to worry with.

On Tue, 16 Oct 2018 20:30:15 -0400, John H.
wrote:

On Tue, 16 Oct 2018 18:46:29 -0400, wrote:

On Tue, 16 Oct 2018 17:05:23 -0400, John H.
wrote:

On Tue, 16 Oct 2018 16:52:44 -0400, "Mr. Luddite" wrote:

On 10/16/2018 3:36 PM, John H. wrote:
On Tue, 16 Oct 2018 14:26:27 -0400, wrote:

On Tue, 16 Oct 2018 14:12:01 -0400, John H.
wrote:

We've had a lot of rain.

I bought a new post for the mailbox. Had Ms. Utility out to mark the underground lines. The new post
needs to be back from the curb 24" to allow for 6" of space from the street and 18" of mailbox. I
had a rod marking the location I wanted to dig. When I went out to look this morning, the utility
marker had put a yellow line right through the spot I wanted for the post. The gas line. Now why the
hell, given the USPS requirements, would the gas company put their damn line right there? Jeeez!

But, here's the quandary. I need a hole 24" deep for the post. About 15" down, I hit the new water
table from all the damn rain we've been having. Keep digging. Now I'm down 24", but the bottom 8-9"
if full of water. I'm thinking if I dump a bag of sacrete down there it'll just become soup. Ditto
with putting dirt down there. As the post and the mailbox are quite heavy, it's got to be set pretty
firmly.

****.

You can either use a tremie (a pipe that goes to the bottom and allows
the concrete to get there unmolested) or just dump it in and get on
with your life.
Considering mail box posts are not bridge pylons, I would just dump it
in (mixed pretty stiff). Dump it in large quantities at the same time
and it will just displace the water and be fine. Sack concrete is
typically 3500 psi gravel mix so even if you lost 90% of the strength,
it would still hold a mailbox post until the post snapped.
The reality is I doubt you lose 25% and less than that if it all goes
in one slug. They place concrete under water all the time.

Yes, concrete placed under water is no problem. But, sacrete isn't concrete 'til it sets. That, I
fear, is the problem. Maybe I'll just dump two bags of sacrete in there - unmixed.



I mentioned in another post ... that's what I did in Florida installing
new posts for a horse pasture. Holes I dug were half filled with water.
It was Sacrete. Poured it in the hole dry, straight from the bag
around the post and it hardened and worked just fine.

I read it. How long did it take to set? The post I'm putting in is this one:

https://www.lowes.com/pd/Cedar-Produ...-Post/50195217

I don't want to stand there for several hours holding it up. And I don't want to pound nails in it
to brace it with 1X4's

You are over thinking this. If you mix the concrete up to about the
consistency of cookie dough and dump it in the hole in bug chunks, the
water will come right out and the stuff at the bottom will be plenty
stiff enough to hold up the post without bracing.
Pouring it in water, while it is dry is the worst thing you could do
because the aggregate will fall out of the cement that is lighter. I
still think for just setting a mailbox post it would be OK.
A don't even bother with concrete for my mailbox. I just backfill with
dirt and tamp it in. That way replacing it when it gets hit is not so
tough.
Maybe Harry will drop you off an empty kitty litter bucket. Those are
just right for this sort of thing since you can more easily hit an 8"
hole with a slug of concrete.

If you really want to get pedantic about this, how long did it take
for the ground water to fill the hole. If you dropped a bilge pump in
there and pumped it out, could you get the post in there and get a
foot of concrete in there before it filled back up?


The water was filling as I was digging. I wouldn't dump the mix on top of the water. I still like
the idea of mixing the sacrete in a wheel barrow, and dropping it into the plastic bag with the post
inside. No extra water to worry with.

The problem is there will be no "bite" with the dirt (lots of voids)
so you might as well just skip the concrete and tamp dirt around the
post. Trust me if you mix that concrete at about a 3 slump, it will
land at the bottom of that hole mostly intact.

On Tue, 16 Oct 2018 21:05:53 -0400, wrote:

On Tue, 16 Oct 2018 20:30:15 -0400, John H.
wrote:

On Tue, 16 Oct 2018 18:46:29 -0400, wrote:

On Tue, 16 Oct 2018 17:05:23 -0400, John H.
wrote:

On Tue, 16 Oct 2018 16:52:44 -0400, "Mr. Luddite" wrote:

On 10/16/2018 3:36 PM, John H. wrote:
On Tue, 16 Oct 2018 14:26:27 -0400, wrote:

On Tue, 16 Oct 2018 14:12:01 -0400, John H.
wrote:

We've had a lot of rain.

I bought a new post for the mailbox. Had Ms. Utility out to mark the underground lines. The new post
needs to be back from the curb 24" to allow for 6" of space from the street and 18" of mailbox. I
had a rod marking the location I wanted to dig. When I went out to look this morning, the utility
marker had put a yellow line right through the spot I wanted for the post. The gas line. Now why the
hell, given the USPS requirements, would the gas company put their damn line right there? Jeeez!

But, here's the quandary. I need a hole 24" deep for the post. About 15" down, I hit the new water
table from all the damn rain we've been having. Keep digging. Now I'm down 24", but the bottom 8-9"
if full of water. I'm thinking if I dump a bag of sacrete down there it'll just become soup. Ditto
with putting dirt down there. As the post and the mailbox are quite heavy, it's got to be set pretty
firmly.

****.

You can either use a tremie (a pipe that goes to the bottom and allows
the concrete to get there unmolested) or just dump it in and get on
with your life.
Considering mail box posts are not bridge pylons, I would just dump it
in (mixed pretty stiff). Dump it in large quantities at the same time
and it will just displace the water and be fine. Sack concrete is
typically 3500 psi gravel mix so even if you lost 90% of the strength,
it would still hold a mailbox post until the post snapped.
The reality is I doubt you lose 25% and less than that if it all goes
in one slug. They place concrete under water all the time.

Yes, concrete placed under water is no problem. But, sacrete isn't concrete 'til it sets. That, I
fear, is the problem. Maybe I'll just dump two bags of sacrete in there - unmixed.



I mentioned in another post ... that's what I did in Florida installing
new posts for a horse pasture. Holes I dug were half filled with water.
It was Sacrete. Poured it in the hole dry, straight from the bag
around the post and it hardened and worked just fine.

I read it. How long did it take to set? The post I'm putting in is this one:

https://www.lowes.com/pd/Cedar-Produ...-Post/50195217

I don't want to stand there for several hours holding it up. And I don't want to pound nails in it
to brace it with 1X4's

You are over thinking this. If you mix the concrete up to about the
consistency of cookie dough and dump it in the hole in bug chunks, the
water will come right out and the stuff at the bottom will be plenty
stiff enough to hold up the post without bracing.
Pouring it in water, while it is dry is the worst thing you could do
because the aggregate will fall out of the cement that is lighter. I
still think for just setting a mailbox post it would be OK.
A don't even bother with concrete for my mailbox. I just backfill with
dirt and tamp it in. That way replacing it when it gets hit is not so
tough.
Maybe Harry will drop you off an empty kitty litter bucket. Those are
just right for this sort of thing since you can more easily hit an 8"
hole with a slug of concrete.

If you really want to get pedantic about this, how long did it take
for the ground water to fill the hole. If you dropped a bilge pump in
there and pumped it out, could you get the post in there and get a
foot of concrete in there before it filled back up?


The water was filling as I was digging. I wouldn't dump the mix on top of the water. I still like
the idea of mixing the sacrete in a wheel barrow, and dropping it into the plastic bag with the post
inside. No extra water to worry with.

The problem is there will be no "bite" with the dirt (lots of voids)
so you might as well just skip the concrete and tamp dirt around the
post. Trust me if you mix that concrete at about a 3 slump, it will
land at the bottom of that hole mostly intact.

That's a good point too. I'm going to buy another bag of sacrete and do as you suggest. Hell, might
just go a 1" slump (as though I had a slump cone in the garage).

On Wed, 17 Oct 2018 06:06:27 -0400, John H.
wrote:

On Tue, 16 Oct 2018 21:05:53 -0400, wrote:

On Tue, 16 Oct 2018 20:30:15 -0400, John H.
wrote:

On Tue, 16 Oct 2018 18:46:29 -0400, wrote:

On Tue, 16 Oct 2018 17:05:23 -0400, John H.
wrote:

On Tue, 16 Oct 2018 16:52:44 -0400, "Mr. Luddite" wrote:

On 10/16/2018 3:36 PM, John H. wrote:
On Tue, 16 Oct 2018 14:26:27 -0400, wrote:

On Tue, 16 Oct 2018 14:12:01 -0400, John H.
wrote:

We've had a lot of rain.

I bought a new post for the mailbox. Had Ms. Utility out to mark the underground lines. The new post
needs to be back from the curb 24" to allow for 6" of space from the street and 18" of mailbox. I
had a rod marking the location I wanted to dig. When I went out to look this morning, the utility
marker had put a yellow line right through the spot I wanted for the post. The gas line. Now why the
hell, given the USPS requirements, would the gas company put their damn line right there? Jeeez!

But, here's the quandary. I need a hole 24" deep for the post. About 15" down, I hit the new water
table from all the damn rain we've been having. Keep digging. Now I'm down 24", but the bottom 8-9"
if full of water. I'm thinking if I dump a bag of sacrete down there it'll just become soup. Ditto
with putting dirt down there. As the post and the mailbox are quite heavy, it's got to be set pretty
firmly.

****.

You can either use a tremie (a pipe that goes to the bottom and allows
the concrete to get there unmolested) or just dump it in and get on
with your life.
Considering mail box posts are not bridge pylons, I would just dump it
in (mixed pretty stiff). Dump it in large quantities at the same time
and it will just displace the water and be fine. Sack concrete is
typically 3500 psi gravel mix so even if you lost 90% of the strength,
it would still hold a mailbox post until the post snapped.
The reality is I doubt you lose 25% and less than that if it all goes
in one slug. They place concrete under water all the time.

Yes, concrete placed under water is no problem. But, sacrete isn't concrete 'til it sets. That, I
fear, is the problem. Maybe I'll just dump two bags of sacrete in there - unmixed.



I mentioned in another post ... that's what I did in Florida installing
new posts for a horse pasture. Holes I dug were half filled with water.
It was Sacrete. Poured it in the hole dry, straight from the bag
around the post and it hardened and worked just fine.

I read it. How long did it take to set? The post I'm putting in is this one:

https://www.lowes.com/pd/Cedar-Produ...-Post/50195217

I don't want to stand there for several hours holding it up. And I don't want to pound nails in it
to brace it with 1X4's

You are over thinking this. If you mix the concrete up to about the
consistency of cookie dough and dump it in the hole in bug chunks, the
water will come right out and the stuff at the bottom will be plenty
stiff enough to hold up the post without bracing.
Pouring it in water, while it is dry is the worst thing you could do
because the aggregate will fall out of the cement that is lighter. I
still think for just setting a mailbox post it would be OK.
A don't even bother with concrete for my mailbox. I just backfill with
dirt and tamp it in. That way replacing it when it gets hit is not so
tough.
Maybe Harry will drop you off an empty kitty litter bucket. Those are
just right for this sort of thing since you can more easily hit an 8"
hole with a slug of concrete.

If you really want to get pedantic about this, how long did it take
for the ground water to fill the hole. If you dropped a bilge pump in
there and pumped it out, could you get the post in there and get a
foot of concrete in there before it filled back up?


The water was filling as I was digging. I wouldn't dump the mix on top of the water. I still like
the idea of mixing the sacrete in a wheel barrow, and dropping it into the plastic bag with the post
inside. No extra water to worry with.

The problem is there will be no "bite" with the dirt (lots of voids)
so you might as well just skip the concrete and tamp dirt around the
post. Trust me if you mix that concrete at about a 3 slump, it will
land at the bottom of that hole mostly intact.

That's a good point too. I'm going to buy another bag of sacrete and do as you suggest. Hell, might
just go a 1" slump (as though I had a slump cone in the garage).

You will be fine even if you just dumped in the dry mix. It is just a
mail box post and concrete is usually overkill to start with.