Sandpaper
 

OK we all use it at some point, but what is the best way to keep it from
floating all over the shop when you use small strips or little pieces?
TIA

Sandpaper
 

I keep my sandpaper in a filing folder. Folder then slips in the book
rack/reference books on the shelf above my bench.

Sandpaper
 

I have a Bank of Small Pigeon Holes made from Square Rain Water Down Pipe,
one Hole for each grade.

Details on my web site at http://www.laymar-crafts.co.uk one of numerous
Tips in the Hints n Tips Section.

RVS

"triker3" wrote in message
...
OK we all use it at some point, but what is the best way to keep it from
floating all over the shop when you use small strips or little pieces?
TIA

Sandpaper
 

Since I use it (mostly) at the lathe I've set up my "system"

At the lathe, I use 1/4 sheet pieces, folded into quarters, with one seam
ripped, so that grit doesn't touch grit. I keep all of them (and the discs
for my 2" disc sander) in an old sour cream container. (Well usually. What
I mean is that when I pick up the work area, they go back into there, so
they are available when I want to sand. Just grab the container.)

I also keep the rest of the full sheets of each grit clipped with a thesis
clip in that same container. The rest of the full sheets are kept in their
cardboard backing from the store, flat in a drawer.

That means that when I wear out one of the quarter sheets, I just pull the
replacement out of the pack (and THROW AWAY THE OLD WORN OUT ONE SO I DON'T
PICK IT UP AGAIN! EVER!) and keep on sanding. When I have used all 4
quarters, I have to trek to the drawer, pull out the next sheet and rip it
into quarters, but I probably needed the break anyhow.

I still find folded sandpaper lying around (I wonder who does that?) but on
straighten up, it goes back to the sour cream container, and gets used up
and then thrown away.

To me, having the stock of quarter sheets easily available, and throwing
away the worn out pieces seems to reduce the hassle.



"triker3" wrote in message
...
OK we all use it at some point, but what is the best way to keep it from
floating all over the shop when you use small strips or little pieces?
TIA

Sandpaper
 

Other tips on sandpaper and using it....

To keep your fingers from burning while sanding place a small piece of
folded cloth behind the paper. It's an old trick that our instructor said
won't be found in a book. Works great!

And...(many already know this I'm sure)....I was tearing off strips of
sandpaper only to discover after sanding that I forgot to write the number
on them. Yesterday a light came on :O) If the strips are torn top to
bottom instead of sideways the number is always there. (Hey - everyone has
to see something for the first time!)

Keith

Sandpaper
 

Hi Salmo

Salmo, I'll give you another tip for not burning your fingers on the
sandpaper. TURN DOWN THE SPEED !!!!
That way the wood will not get to hot as well, it's the better of the
two IMO.

Have fun and take care
Leo Van Der Loo


Salmo wrote:
Other tips on sandpaper and using it....

To keep your fingers from burning while sanding place a small piece of
folded cloth behind the paper. It's an old trick that our instructor said
won't be found in a book. Works great!

And...(many already know this I'm sure)....I was tearing off strips of
sandpaper only to discover after sanding that I forgot to write the number
on them. Yesterday a light came on :O) If the strips are torn top to
bottom instead of sideways the number is always there. (Hey - everyone has
to see something for the first time!)

Keith

Sandpaper
 

Thanks..I sand at the last speed I used while turning and have yet to change
the speed to slow. The wood doesn't get hot because I don't keep the paper
there long enough to burn as I'm changing from 100-120-180-220-320-400-800
until a sheen shows. ...

The cloth piece behind the sandpaper really does do the trick. I'll try the
slower speed anyway just to compare the finish difference (or non
difference).

Keith

Sandpaper
 

In article ,
"Salmo" wrote:

Thanks..I sand at the last speed I used while turning and have yet to change
the speed to slow. The wood doesn't get hot because I don't keep the paper
there long enough to burn as I'm changing from 100-120-180-220-320-400-800
until a sheen shows. ...

The cloth piece behind the sandpaper really does do the trick. I'll try the
slower speed anyway just to compare the finish difference (or non
difference).

On some woods, you can cause heat checks in the end grain from
overheating. My rule is that if it's too hot to continue sanding, then
slow it down.

Years ago, a regular to this group, Lyn Mangiameli, discussed slow speed
sanding. After I tried it I was a convert - I now rarely sand above 500
rpm - and oftentimes it's much slower depending on the work diameter.
I'll see if I can look up the thread and post the link.

--
Owen Lowe

Northwest Woodturners
Pacific Northwest Woodturning Guild
___
Tips fer Turnin': Place a sign, easily seen as you switch on your lathe, warning you to remove any and all rings from your fingers. Called degloving, extended hardware can grab your ring and rip it off your finger. A pic for the strong of stomach: www.itim.nsw.gov.au/go/objectid/2A3AC703-1321-1C29-70B067DC88E16BFC/index.cfm

Besides, rings can easily mar the surface of a turning as you check for finished smoothness.

Sandpaper
 

"Owen Lowe" wrote in message
...
On some woods, you can cause heat checks in the end grain from
overheating. My rule is that if it's too hot to continue sanding, then
slow it down.


Hmmmm, my book says sand with less pressure at whatever speed you care and
you'll get less heat. Coefficient of friction being basically the same,
(might actually be less at low pressure) it all depends on pressure, not
speed.

Years ago, a regular to this group, Lyn Mangiameli, discussed slow speed
sanding. After I tried it I was a convert - I now rarely sand above 500
rpm - and oftentimes it's much slower depending on the work diameter.
I'll see if I can look up the thread and post the link.


Yeah, Lyn discussed a lot of things. Some of which made good sense. This
is not one of them. Lathe speed when paper is unpowered is worth keeping at
a reasonable rate, but that's for the operator's safety. When paper is
powered and circular, you can have an additive, subtractive, or composite
speed _at any given point on the circumference_, which really complicates
things. Makes pontification on speed just that, though once again, speed
doesn't produce heat.

Sort of like your comparison of the weight of the Robust vs Oneway, it's
meaningless. Rigidity is what counts. The rest can be bolted securely in
place, and already is on the heavier lathe.

Sandpaper
 

Hmmmm, my book says sand with less pressure at whatever speed you care and
you'll get less heat. Coefficient of friction being basically the same, (might
actually be less at low pressure) it all depends on pressure, not speed.

George, what you say is true, but only for limited ranges of pressure and
speeds. Few things in nature are linear. My book, The Machinist's Handbook,
says this about friction:

For low pressures the friction is directly proportional to the normal pressure
between the two surfaces (Just as you say), but goes on to say:

At very low velocities the friction is independent of the velocity (similar to
what you say)

For high velocities the friction (and coeficient of friction) decreases (the
opposite of what you say)

The friction is independent of the areas in contact.

What this means for heat buildup is that pressing with the same force with three
fingers instead of one yields the same friction (and stock removal) but it
generates less heat per surface area since it is spread out over a larger
contact area. Going faster reduces the friction (and therefore heat buildup),
leading to longer abrasive life, and at the same time the increased speed will
have a cooling effect upon the surfaces, too.

However, increased speed will result in increased injury in the event of an
accident.

Dan

Sandpaper
 

"Dan Bollinger" wrote in message
...
Hmmmm, my book says sand with less pressure at whatever speed you care
and you'll get less heat. Coefficient of friction being basically the
same, (might actually be less at low pressure) it all depends on
pressure, not speed.

George, what you say is true, but only for limited ranges of pressure and
speeds. Few things in nature are linear. My book, The Machinist's
Handbook, says this about friction:

For low pressures the friction is directly proportional to the normal
pressure between the two surfaces (Just as you say), but goes on to say:

At very low velocities the friction is independent of the velocity
(similar to what you say)

For high velocities the friction (and coeficient of friction) decreases
(the opposite of what you say)

The friction is independent of the areas in contact.

What this means for heat buildup is that pressing with the same force with
three fingers instead of one yields the same friction (and stock removal)
but it generates less heat per surface area since it is spread out over a
larger contact area. Going faster reduces the friction (and therefore
heat buildup), leading to longer abrasive life, and at the same time the
increased speed will have a cooling effect upon the surfaces, too.1

Well, no. Five pounds per square inch pressure is still five pounds per
square inch whether you have six square inches in contact or three. If you
had a constant weight (pressure) what you said about reducing the force per
unit of area would be true. That's why the corrugated sole on the jack I'm
using to level some panels just now generates essentially the same friction
as a solid one, less a bit of suction on its own, but different depending on
how hard I press. I am assuming, of course, that 200 pounds of Polack is
not capable of exerting the consistent pressure of his entire bulk - a
limiting factor - in this case or with the sandpaper.

Factor in the next obvious step, Dan. As you press, you dig in deeper,
burying the grit more to the backing, increasing the coefficient of friction
and resistance. If you don't press, your depth of "cut" is less,
coefficient of friction less, and so forth to the obvious conclusion.

Sandpaper
 

"George" wrote in message
. ..

"Dan Bollinger" wrote in message
...
Hmmmm, my book says sand with less pressure at whatever speed you care
and you'll get less heat. Coefficient of friction being basically the
same, (might actually be less at low pressure) it all depends on
pressure, not speed.

George, what you say is true, but only for limited ranges of pressure and
speeds. Few things in nature are linear. My book, The Machinist's
Handbook, says this about friction:

For low pressures the friction is directly proportional to the normal
pressure between the two surfaces (Just as you say), but goes on to say:

At very low velocities the friction is independent of the velocity
(similar to what you say)

For high velocities the friction (and coeficient of friction) decreases
(the opposite of what you say)

The friction is independent of the areas in contact.

What this means for heat buildup is that pressing with the same force
with three fingers instead of one yields the same friction (and stock
removal) but it generates less heat per surface area since it is spread
out over a larger contact area. Going faster reduces the friction (and
therefore heat buildup), leading to longer abrasive life, and at the same
time the increased speed will have a cooling effect upon the surfaces,
too.1

Well, no. Five pounds per square inch pressure is still five pounds per
square inch whether you have six square inches in contact or three. If you
had a constant weight (pressure) what you said about reducing the force
per unit of area would be true. That's why the corrugated sole on the jack
I'm using to level some panels just now generates essentially the same
friction as a solid one, less a bit of suction on its own, but different
depending on how hard I press. I am assuming, of course, that 200 pounds
of Polack is not capable of exerting the consistent pressure of his entire
bulk - a limiting factor - in this case or with the sandpaper.

Factor in the next obvious step, Dan. As you press, you dig in deeper,
burying the grit more to the backing, increasing the coefficient of
friction and resistance. If you don't press, your depth of "cut" is less,
coefficient of friction less, and so forth to the obvious conclusion.

I've been following this thread and think this is a comparison of apples and
oranges.

I feel that a good point to start is an empirical test and then come up with
an explanation to fit the results.

Test 1. Rest your hand on a rotating smooth spindle of wood at a low speed
and at a high speed and decide on which your hand get hotter.

Test 2. Run the spindle at 500 rpm and grip lightly then tighten your grip
on the wood.

For those cautious ones who are concerned about health and safety, loosing
their hands, stripping the skin from their palms or suing me. The answer is
the faster it goes and the harder you grip it the hotter it gets (but you
knew that already).

If we are talking about sanding then the concern is kinetic friction which
increases with the force applied (as has been stated) and presumably varies
with the grade of sandpaper but is not dependant on the area of contact. It
is also a dimensionless quantity (it is just a number). So friction does not
generate heat, something else has to be happening also.

Checkout 'Energy of friction' at the bottom of the page on:-
http://www.answers.com/topic/friction-1

The energy (heat) = the normal reaction force x coefficient of kinetic
friction x distance travelled.

'The normal reaction force' = how much you press on the sandpaper
'Coefficient of kinetic friction' = depends on the wood and sandpaper
'Distance travelled' = in any unit of time, say 1 min = rpm x Pi x diameter
of the piece being sanded.

So the more you press on and the faster the lathe goes the more heat is
generated.

This would seem to tie the theory to empirical test.

OK finished now for those still reading this and I'm going to find my flak
jacket.

BillR

Sandpaper
 

Aren't we sidetracked here? The question is not heat or friction, but what
delivers the best looking piece of work.

My experience is that when I slow down the work, it looks better after I
sand it. Not exactly sure why, but it does. I have fewer deep scratches,
and better control so I don't sand off the sharp details. And high speed
sanding on softwood face turning, is a guarantee to ripples because the
softer summer wood is removed, leaving the harder spring wood (?).

Also it doesn't throw the dust as far, and the feel of the project is less
frantic--like I'm in control, not the machine.

My $.02

Old Guy


"Owen Lowe" wrote in message
...
In article ,
"Salmo" wrote:

Thanks..I sand at the last speed I used while turning and have yet to
change
the speed to slow. The wood doesn't get hot because I don't keep the
paper
there long enough to burn as I'm changing from
100-120-180-220-320-400-800
until a sheen shows. ...

The cloth piece behind the sandpaper really does do the trick. I'll try
the
slower speed anyway just to compare the finish difference (or non
difference).

On some woods, you can cause heat checks in the end grain from
overheating. My rule is that if it's too hot to continue sanding, then
slow it down.

Years ago, a regular to this group, Lyn Mangiameli, discussed slow speed
sanding. After I tried it I was a convert - I now rarely sand above 500
rpm - and oftentimes it's much slower depending on the work diameter.
I'll see if I can look up the thread and post the link.

--
Owen Lowe

Northwest Woodturners
Pacific Northwest Woodturning Guild
___
Tips fer Turnin': Place a sign, easily seen as you switch on your lathe,
warning you to remove any and all rings from your fingers. Called
degloving, extended hardware can grab your ring and rip it off your
finger. A pic for the strong of stomach:
www.itim.nsw.gov.au/go/objectid/2A3AC703-1321-1C29-70B067DC88E16BFC/index.cfm

Besides, rings can easily mar the surface of a turning as you check for
finished smoothness.

Sandpaper
 

"Old guy" wrote in message
news:AWNlh.197913$aJ.54273@attbi_s21...
Aren't we sidetracked here? The question is not heat or friction, but
what delivers the best looking piece of work.

My experience is that when I slow down the work, it looks better after I
sand it. Not exactly sure why, but it does. I have fewer deep scratches,
and better control so I don't sand off the sharp details. And high speed
sanding on softwood face turning, is a guarantee to ripples because the
softer summer wood is removed, leaving the harder spring wood (?).

Also it doesn't throw the dust as far, and the feel of the project is less
frantic--like I'm in control, not the machine.


I think if you sand without support for the sander other than the work
itself, you'll find that to be true. Less energy on the slow piece to throw
the tool back at you if you get a bum angle, and less likely that the bum
angle that tosses you (dare we say high-friction contact?) will cause a dig
when it does. Stopping the work entirely is risky business, however. Now
the scratch arcs form quickly from an improper tilt, and worse than arcs,
digs are possible. I like to sand with the support of my toolrest, more or
less an extension of the cutting process, where the work comes to the edge
for removal. Makes it easier to compensate for surface hardness differences
as well.

You must be sanding in some completely different format that I if travel on
the dust is a concern. I like it to travel, and encourage it to do so -
straight into my strategically place collector. Keeps it low and away from
my nose.

Sandpaper
 

In article ,
"BillR" wrote:

The answer is the faster it goes and the harder you grip

or push

it the hotter it gets (but you knew that already).

It's much more difficult to judge excessive heat buildup when machine or
rotary sanding. The heat will shorten the life of Velcro pads and if one
is not using the finger-backing method. The hooks melt away and then the
paper won't stay stuck.

--
Owen Lowe

Northwest Woodturners
Pacific Northwest Woodturning Guild
___
Tips fer Turnin': Place a sign, easily seen as you switch on your lathe, warning you to remove any and all rings from your fingers. Called degloving, extended hardware can grab your ring and rip it off your finger. A pic for the strong of stomach: www.itim.nsw.gov.au/go/objectid/2A3AC703-1321-1C29-70B067DC88E16BFC/index.cfm

Besides, rings can easily mar the surface of a turning as you check for finished smoothness.

Sandpaper
 

In article ,
Owen Lowe wrote:

Years ago, a regular to this group, Lyn Mangiameli, discussed slow speed
sanding. After I tried it I was a convert - I now rarely sand above 500
rpm - and oftentimes it's much slower depending on the work diameter.
I'll see if I can look up the thread and post the link.

http://groups.google.com/group/rec.c...3d44827484e9de
1b?&hl=en

--
Owen Lowe

Northwest Woodturners
Pacific Northwest Woodturning Guild
___
Tips fer Turnin': Place a sign, easily seen as you switch on your lathe, warning you to remove any and all rings from your fingers. Called degloving, extended hardware can grab your ring and rip it off your finger. A pic for the strong of stomach: www.itim.nsw.gov.au/go/objectid/2A3AC703-1321-1C29-70B067DC88E16BFC/index.cfm

Besides, rings can easily mar the surface of a turning as you check for finished smoothness.