On Sun, 26 Mar 2006 13:23:53 GMT, Ignoramus5876
wrote:

Our old mailbox was hit by cars, snowplows etc, too many times. It is
falling apart. (no foul play involved, just a lot of idiot drivers and
snowplow operators)

I made a swinging arm for a mailbox, so that when the mailbox is hit,
it swings away and then back.

So, now is the time for installing a new mailbox post. I bought a 30"
post support that is made to be beaten into the ground with a
sledgehammer. It is like an arrow with four fins.

I am now having second thoughts and am not sure if this is a good long
term solution. One of the reasons is that there is going to be quite a
bit of tipping moment due to a little longer swinging arm. (my guess
about 40-60 extra foot pounds of moment of force).

I want this mailbox to stay vertical and not "tip".

I live in Northern Illinois, so we have frequent freeze/unfreeze
cycles of soil.

So... What's a good way of mounting a mailbox post? Maybe I should set
that mailbox post support at least partially into concrete? (ie, digh
a shallow hole, beat it into the hole level with ground, and fill the
hole with concrete?

i

There are lots of those in MN. You just need a longer post. Buy,
borrow or rent a manual post hole digger, like this:
http://www.tooled-up.com/Product.asp...st-Hole-Digger
If you lived nearby I'd loan you mine.

Dig a hole a bit over a foot in diameter and 4 feet deep. Put in
one of those 12" dia fiber tubes, Sonotube I think it's called.
Home Depot. Plant post in center, supported plumb with temporary
supports if necessary. Fill tube with concrete, backfill and tamp
around the result.

It doesn't really take very long to do it right, and you'll only have
to do it once.

Thing is, you want some of the concrete well below the frostine, not
just a cap sitting on top. You can stop pouring 6" or so below ground
level and backfill with soil so grass will grow there and it's easy
to mow.

What Don said about the 4' depth. 36" is marginal, 42" is minimum, 48'
is the target.

Don Foreman wrote:
On Sun, 26 Mar 2006 13:23:53 GMT, Ignoramus5876
wrote:


Our old mailbox was hit by cars, snowplows etc, too many times. It is
falling apart. (no foul play involved, just a lot of idiot drivers and
snowplow operators)

I made a swinging arm for a mailbox, so that when the mailbox is hit,
it swings away and then back.

So, now is the time for installing a new mailbox post. I bought a 30"
post support that is made to be beaten into the ground with a
sledgehammer. It is like an arrow with four fins.

I am now having second thoughts and am not sure if this is a good long
term solution. One of the reasons is that there is going to be quite a
bit of tipping moment due to a little longer swinging arm. (my guess
about 40-60 extra foot pounds of moment of force).

I want this mailbox to stay vertical and not "tip".

I live in Northern Illinois, so we have frequent freeze/unfreeze
cycles of soil.

So... What's a good way of mounting a mailbox post? Maybe I should set
that mailbox post support at least partially into concrete? (ie, digh
a shallow hole, beat it into the hole level with ground, and fill the
hole with concrete?

i


There are lots of those in MN. You just need a longer post. Buy,
borrow or rent a manual post hole digger, like this:
http://www.tooled-up.com/Product.asp...st-Hole-Digger
If you lived nearby I'd loan you mine.

Dig a hole a bit over a foot in diameter and 4 feet deep. Put in
one of those 12" dia fiber tubes, Sonotube I think it's called.
Home Depot. Plant post in center, supported plumb with temporary
supports if necessary. Fill tube with concrete, backfill and tamp
around the result.

It doesn't really take very long to do it right, and you'll only have
to do it once.

Thing is, you want some of the concrete well below the frostine, not
just a cap sitting on top. You can stop pouring 6" or so below ground
level and backfill with soil so grass will grow there and it's easy
to mow.

Thank you Don, Roy and Bruce. I have never seen 12" by 4' deel
concrete bases for mailboxes, myself. Unfortunately, by the time I
read your messages, I already advanced along the line of not very deep
concrete and a big stake held by the concrete and pounded a foot or so
below it.. I made sure that the concrete pad would be extended beyond
the center of gravity of this mailbox post.

You're setting yourself up for heartache. Even the pros
make this mistake, I was driving along I-80 in PA a couple
years ago, after they'd had a really cold spell that winter.

Every end of every guardrail, where it had been stuck in the
gound, had been encased in concrete. And every one had
been pushed back out by 6" to a foot.

I think a shallow pad would be your absolute worst option
for frost. Either dig it deep and fill with concrete, or dig it
and fill with gravel. Anything else will just p*ss you off after
2 or 3 hard winters, when the water gets under it and expands
and tilts your spiffy new post.

My $0.02,
--Glenn Lyford