three questions

1) What does for example 7075-T6 mean? I read
it is stell alloy and heat treatment but
what do the digits and letters mean, or are
they just a designation so you can look up
the properties, and if so where?

2) A guy has had a flat tire several times but
the tire looks OK. The suspicion is, if the
rim tape is too broad for the rim so it
forms a flat "U" letter, and what happens is
the ends cut thru the tube. Is this heard
of? The rim tape is from Specialized.
It looks a little broad but I wouldn't have
noticed unless there was this
little mystery.

3) On a boat I'm working on, there are several
cases where the screws are loose in their
holes. What do you typically do?
Get a longer screw? Or do you use Loctite,
crazy-glue, etc.?

Thank you

--
underground experts united
http://user.it.uu.se/~embe8573

On 7/23/2017 6:44 PM, Emanuel Berg wrote:
1) What does for example 7075-T6 mean? I read
it is stell alloy and heat treatment but
what do the digits and letters mean, or are
they just a designation so you can look up
the properties, and if so where?

2) A guy has had a flat tire several times but
the tire looks OK. The suspicion is, if the
rim tape is too broad for the rim so it
forms a flat "U" letter, and what happens is
the ends cut thru the tube. Is this heard
of? The rim tape is from Specialized.
It looks a little broad but I wouldn't have
noticed unless there was this
little mystery.

3) On a boat I'm working on, there are several
cases where the screws are loose in their
holes. What do you typically do?
Get a longer screw? Or do you use Loctite,
crazy-glue, etc.?

Thank you


1. 7075 is a material. It's an aluminum with a specific
alloy composition.
T6 is a temper/hardness finish value.
Details he
http://www.esabna.com/us/en/educatio...ion-system.cfm

2. I do not know but you can. Mark your tire, rim and valve
before removing the tube. Inflate tube, mark the leak. The
injury will either be on the outside = tire problem or it
will be on the inside = rim/rim liner problem.

If your rim liner occludes the tire bead seat, blue in image
he
http://www.yellowjersey.org/photosfr...st/rimpins.jpg
then the tire will be difficult or impossible to seat
properly. Other problems may ensue as well. Note center rim
style takes a fabric or polyurethane liner, left and right
use a rubber liner.

3. Assuming this is a wooden boat, I would consult a man who
knows wooden boats.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Mon, 24 Jul 2017 01:44:33 +0200, Emanuel Berg
wrote:

1) What does for example 7075-T6 mean? I read
it is stell alloy and heat treatment but
what do the digits and letters mean, or are
they just a designation so you can look up
the properties, and if so where?

7975 is a specific aluminum alloy which contains zinc among other
elements and is probably the strongest of the various aluminum alloys.

It was developed in Japan in 1943 and was, perhaps, one of the reasons
that Japanese aircraft had such good performance.

The "T" designation is a designation of physical properties usually
brought about by a combination of heat treatment and age hardening.

T0 has a tensile strength of ~280MPa and a yield strength of ~140 MPa
while T6 has a tensile strength of ~540 MPa and a yield strength of
~480 MPa.

There are 5 (if I remember correctly) different codes used for 7075.

2) A guy has had a flat tire several times but
the tire looks OK. The suspicion is, if the
rim tape is too broad for the rim so it
forms a flat "U" letter, and what happens is
the ends cut thru the tube. Is this heard
of? The rim tape is from Specialized.
It looks a little broad but I wouldn't have
noticed unless there was this
little mystery.

3) On a boat I'm working on, there are several
cases where the screws are loose in their
holes. What do you typically do?
Get a longer screw? Or do you use Loctite,
crazy-glue, etc.?

Thank you

If this is a "wood screw" depending on what the screw is holding
perhaps a larger diameter screw. If a "machine screw" then perhaps
loctite.
--
Cheers,

John B.

AMuzi wrote:

[...]

Excellent, thank you!

--
underground experts united
http://user.it.uu.se/~embe8573

John B. Slocomb wrote:

If this is a "wood screw" depending on what
the screw is holding perhaps a larger
diameter screw. If a "machine screw" then
perhaps loctite.

It is all big wood screws. A larger diameter
won't do as it'll then be too big to pass thru
the hole of whatever it is it should hold.

Could you fill the hole with something and then
screw anew?

Or forget about the screw and glue the detail?
Will that carry enough strength, and
be resistant?

Typically it is three screws in a circle, and
one of them is loose.

--
underground experts united
http://user.it.uu.se/~embe8573

On Sunday, July 23, 2017 at 10:26:26 PM UTC-4, Emanuel Berg wrote:
John B. Slocomb wrote:

If this is a "wood screw" depending on what
the screw is holding perhaps a larger
diameter screw. If a "machine screw" then
perhaps loctite.

It is all big wood screws. A larger diameter
won't do as it'll then be too big to pass thru
the hole of whatever it is it should hold.

Could you fill the hole with something and then
screw anew?

Or forget about the screw and glue the detail?
Will that carry enough strength, and
be resistant?

Typically it is three screws in a circle, and
one of them is loose.

--
underground experts united
http://user.it.uu.se/~embe8573

Epoxy in a wood plug. When cured drill the plug and insert the screw.

Cheers

Emanuel Berg wrote:
:John B. Slocomb wrote:

: If this is a "wood screw" depending on what
: the screw is holding perhaps a larger
: diameter screw. If a "machine screw" then
: perhaps loctite.

:It is all big wood screws. A larger diameter
:won't do as it'll then be too big to pass thru
:the hole of whatever it is it should hold.

:Could you fill the hole with something and then
:screw anew?

In general carpentry, the solution is to drill the hole in the wood out
to a standard size, and glue with wood glue a dowel (wooden rod) the same
size as the drilled hole in the hole. Once the glue is dry, cut it flush
with the surface with a chisel, redrill the hole, reinstall the screw.
The end result is at least as good as new, often better. I have done
this for countless door hinge screws, and my carpentry tool bag has a
selection of dowels cut to 2" lengths for the purpose. Sometimes, it
makes sense to replace a bigger section of wood, but the general idea is
the same. For things that don't carry much load, a couple wooden match
sticks or toothpicks stuck around the edge of the hole can give the screw
something to bite on.

I would expect you could do something similar on a boat, but I'd take
expert advice on what glues are suitable.


--
sig 20

David Scheidt wrote:

In general carpentry, the solution is to
drill the hole in the wood out to a standard
size, and glue with wood glue a dowel (wooden
rod) the same size as the drilled hole in the
hole. Once the glue is dry, cut it flush with
the surface with a chisel, redrill the hole,
reinstall the screw.

Any preference what woods the dowel should be?

The same as the original material?

Doesn't matter just hard?

--
underground experts united
http://user.it.uu.se/~embe8573

On Mon, 24 Jul 2017 04:26:22 +0200, Emanuel Berg
wrote:

Could you fill the hole with something and then
screw anew?

Yes. That's what I do. Most commonly, I use strips of wood or
toothpicks arranged in a bundle. I cram them into the hole and break
off the excess wood. Re-install the wood screw and you're done.

However, if the sides of the hole a smooth, the strips of wood or
toothpicks might slide in and out. For those, I just slop some wood
glue onto the sides of the hole before I insert the wood strips.

Typically it is three screws in a circle, and
one of them is loose.

Deck plate?
http://www.beckson.com/dpinstall.html
http://www.downwindmarine.com/Deck-Plates-p-1-c-127.html
If the metal plate gets walked on, it's likely that stepping on an
edge produces a rocking action that prys out the nearest screw, much
like a can opener. It's a common problem. There are many solutions,
but I've found the best is to simply flatten and sand flat the cover
plate and whatever lives under the plate so that it doesn't rock when
someone stands on an edge. If the deck is warped or splintered,
that's not going to happen. For those, I suggest replacing the metal
deck plate with a plastic equivalent, which will bend when stepped on.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann wrote:

Deck plate?
http://www.beckson.com/dpinstall.html
http://www.downwindmarine.com/Deck-Plates-p-1-c-127.html
If the metal plate gets walked on, it's
likely that stepping on an edge produces
a rocking action that prys out the nearest
screw, much like a can opener. It's a common
problem. There are many solutions, but I've
found the best is to simply flatten and sand
flat the cover plate and whatever lives under
the plate so that it doesn't rock when
someone stands on an edge. If the deck is
warped or splintered, that's not going to
happen. For those, I suggest replacing the
metal deck plate with a plastic equivalent,
which will bend when stepped on.

Very interesting, thank you.

--
underground experts united
http://user.it.uu.se/~embe8573