118 MODEL AVIATION
The most important tool in the workshop
[[email protected]]
Control Line Aerobatics Bob Hunt
Purchase a selection of grits and types of sandpaper. A variety
helps with progress when building a model. Bob prefers the new
“no clog” sandpapers.
Great Planes sells a variety of extruded-aluminum sanding bars.
Purchase several of these in an assortment of lengths and fit them
with a range of grits of sandpaper.
NO TOOL IS more valuable to me in the shop than sandpaper.
That’s a strong statement, I know, and there are so many important
and useful tools for modeling that it might even seem a bit arrogant.
But it’s true.
In the last column I promised to continue the shop-stocking thread
I am on by covering sanding and filing tools. I could write a fairly
good-sized book on the subject of sanding alone, but here I’ll try to
define the minimums needed and augment that list later.
If it’s true that “God is in the details,” then sandpaper is a divine
material. Sanding technique is what separates the outstanding models
from the okay-looking models. Having the appropriate sanding and
filing tools and knowing how to use them is where the art of this
hobby—at least as far as building is concerned—lies.
For our purposes, we should have a broad selection of sandpaper
types and grits. For woodworking purposes I use and recommend one
of the new clog-resistant sandpapers. I’ve purchased them from
Norton, 3M, and Ace Hardware, and I have found all of them to work
well for sanding balsa wood.
The Norton brand is called “3X” paper, the 3M brand is
“Sandblaster,” and Ace simply calls it “Bare Wood Sandpaper.” All of
these come in a wide variety of grits, and I recommend that you
purchase a sleeve each of 400, 320, 220, 150, and 80. You will find
uses for all of them when building—trust me.
When you get to the finishing stages, you will also need a selection
of Silicon Carbide sandpaper. This type is used for wet sanding. The
grits you will most likely need range from 1,200 to 400. Again,
purchase a sleeve of each.
You will perform most sanding with either a block or some other
shape of platen. Resist the urge to do this work using your fingers as
backing for sandpaper; the result will be an uneven surface that will
look “wavy” when you apply the finish.
You can make sanding blocks from a variety of materials. Normal
woodworking blocks can be made from 2- to 21/2-inch-wide by 11-
inch-long (the normal length of the sandpaper you will buy) by 1/2- to
3/4-inch-thick pieces of Medium-Density Fiberboard (MDF). These
can be cut out on a band saw.
If you opt to make sanding blocks in this manner, be certain to
slightly chamfer the edges of the blocks so that they will not “dig” into
the balsa parts on which you will be using them.
You are not constrained to making blocks that are the full length of
the sandpaper. You will probably need to make many custom sanding
blocks in numerous shapes and sizes, to accommodate specific
building needs.
This is where the modeler’s natural engineering talents come into
play. Be creative in visualizing what type of sanding tool you need for
a specific purpose, and then craft that part accordingly.
Dowels are very useful in creating sanding tools for concave areas
such as fillets. Soft foam, such as 1-pound-per-cubic-foot expanded
polystyrene, as is used for our foam wings, can be cut into various
useful shapes and employed as sanding blocks.
The advantage is that the foam will crush if it is pushed into a
corner or fillet, and it will not dent or ding your model. I use foambacked
sanding blocks for a multitude of model building and
finishing-sanding chores.
Lately I’ve been lazy about making my own generic wood sanding
blocks and have switched to a variety of the Great Planes extrudedaluminum
Easy-Touch Bar Sanders. There is a wide selection of
lengths from which to choose.
I recommend purchasing quite a few of the 11-inch-long Bar
Sanders (part GPMR6170) and at least one or two of the longer
lengths for sanding sheeted foam wings. There is a 22-inch
(GPMR6172), a 33-inch (GPMR6174), and a 44-inch (GPMR6176).
I have a large collection of the 11-inch bars and several of the
longer ones, and I have fitted them with a variety of grits of sandpaper.
I use them until the paper starts to dull, and then I replace the paper on
all of them at one time.
It usually takes the better part of a morning to change the paper on
all of my sanding blocks, but the result is that I always have sharp
tools.
Say no to clutter. A block of EPS (expanded polystyrene) foam can
be made into a handy holder and organizer for needle files and
other small hand tools.
09sig4x_00MSTRPG.QXD 7/23/10 10:23 AM Page 118
I use 3M Super 77 spray adhesive to
attach the sandpaper to the aluminum blocks.
I apply the adhesive to the back of the paper
and let it get tacky. Then I place the sanding
block facedown on the paper against a clean,
flat surface, and press hard to make sure that
the sandpaper is attached completely to the
flat surface of the sanding bar.
Then I roll the edges of the sanding bar to
make the sandpaper conform to the edges.
This prevents the paper from gouging my
balsa parts when I use the bar. I trim the
edges against the side of the block with a
single-edge razor blade and reroll the edges
again, just to be sure.
To remove the sandpaper when it has
worn out, lay the blocks in a shallow bath of
mineral spirits for a few minutes. I use a
shallow cookie sheet for this, and I leave it
outside while the sandpaper delaminates from
the block. (This cookie sheet is a dedicated
shop item and is never used for cookie
making.) I wipe the surface of the sanding
bars clean with a fresh paper towel, and they
are ready to be resurfaced.
For finishing purposes, foam-backed
sanding blocks are the ticket. They are soft
enough to not dent anything, but they are
supportive enough to allow the surface to be
sanded smooth and flat.
I cut a piece of 1/2-inch-thick foam that is
the exact size of a full sheet of sandpaper, and
then I attach the sandpaper to the foam
backing. I used to use 3M Formula 77 for
this, but the formula has been changed and
now it (or the solvents in it) will attack the
foam. You can use one of the new
polyurethane glues instead, or even a thin coat
of epoxy.
The curing time before use will be longer,
so make several sheets at one time and slice
the size of block you need from one sheet.
You can cut tiny blocks to do detail work or
longer blocks to sand large areas.
Another great sanding tool is an industrialgrade
(professional grade?) emery board.
These can be purchased in several grits, and
some are available with different grits on each
side.
These boards, or “sanding sticks,” are 7
inches long and backed with Mylar. I get mine
from See Temp, but you can also find them at
beauty-supply stores or Web sites. Once you
try emery boards, you will probably never be
able to—or want to—build without them.
Files: Get a set of good-quality files. You will
need a flat file that is approximately 3/4 inch
wide, a half-round file, and several round, or
rat-tail, files. It is also a good idea to purchase
a set of high-quality needle files for fine work.
You will at least need a round and a threecornered
needle file.
Keep your eyes open at tool stores for
specials on files, and add to your collection.
You will find uses for them in time.
To store my needle files—and various
other small hand tools—and have them ready
at a moment’s notice for use in building, I
have a block of foam with a grid pattern
drawn on the top surface. At each grid
intersection I punched a hole that accepts a
file, screwdriver, spinner wrench, etc.
This “organizer” makes it much easier to
find the necessary tool and retrieve it quickly.
It also keeps the bench neat and free of clutter.
I am out of space again and have not yet
discussed the most useful and amazing line of
sanding and filing tools. I’ll keep you in
suspense about these until next time.
Until then, fly Stunt! MA
Edition: Model Aviation - 2010/09
Page Numbers: 118,119,120
Edition: Model Aviation - 2010/09
Page Numbers: 118,119,120
118 MODEL AVIATION
The most important tool in the workshop
[[email protected]]
Control Line Aerobatics Bob Hunt
Purchase a selection of grits and types of sandpaper. A variety
helps with progress when building a model. Bob prefers the new
“no clog” sandpapers.
Great Planes sells a variety of extruded-aluminum sanding bars.
Purchase several of these in an assortment of lengths and fit them
with a range of grits of sandpaper.
NO TOOL IS more valuable to me in the shop than sandpaper.
That’s a strong statement, I know, and there are so many important
and useful tools for modeling that it might even seem a bit arrogant.
But it’s true.
In the last column I promised to continue the shop-stocking thread
I am on by covering sanding and filing tools. I could write a fairly
good-sized book on the subject of sanding alone, but here I’ll try to
define the minimums needed and augment that list later.
If it’s true that “God is in the details,” then sandpaper is a divine
material. Sanding technique is what separates the outstanding models
from the okay-looking models. Having the appropriate sanding and
filing tools and knowing how to use them is where the art of this
hobby—at least as far as building is concerned—lies.
For our purposes, we should have a broad selection of sandpaper
types and grits. For woodworking purposes I use and recommend one
of the new clog-resistant sandpapers. I’ve purchased them from
Norton, 3M, and Ace Hardware, and I have found all of them to work
well for sanding balsa wood.
The Norton brand is called “3X” paper, the 3M brand is
“Sandblaster,” and Ace simply calls it “Bare Wood Sandpaper.” All of
these come in a wide variety of grits, and I recommend that you
purchase a sleeve each of 400, 320, 220, 150, and 80. You will find
uses for all of them when building—trust me.
When you get to the finishing stages, you will also need a selection
of Silicon Carbide sandpaper. This type is used for wet sanding. The
grits you will most likely need range from 1,200 to 400. Again,
purchase a sleeve of each.
You will perform most sanding with either a block or some other
shape of platen. Resist the urge to do this work using your fingers as
backing for sandpaper; the result will be an uneven surface that will
look “wavy” when you apply the finish.
You can make sanding blocks from a variety of materials. Normal
woodworking blocks can be made from 2- to 21/2-inch-wide by 11-
inch-long (the normal length of the sandpaper you will buy) by 1/2- to
3/4-inch-thick pieces of Medium-Density Fiberboard (MDF). These
can be cut out on a band saw.
If you opt to make sanding blocks in this manner, be certain to
slightly chamfer the edges of the blocks so that they will not “dig” into
the balsa parts on which you will be using them.
You are not constrained to making blocks that are the full length of
the sandpaper. You will probably need to make many custom sanding
blocks in numerous shapes and sizes, to accommodate specific
building needs.
This is where the modeler’s natural engineering talents come into
play. Be creative in visualizing what type of sanding tool you need for
a specific purpose, and then craft that part accordingly.
Dowels are very useful in creating sanding tools for concave areas
such as fillets. Soft foam, such as 1-pound-per-cubic-foot expanded
polystyrene, as is used for our foam wings, can be cut into various
useful shapes and employed as sanding blocks.
The advantage is that the foam will crush if it is pushed into a
corner or fillet, and it will not dent or ding your model. I use foambacked
sanding blocks for a multitude of model building and
finishing-sanding chores.
Lately I’ve been lazy about making my own generic wood sanding
blocks and have switched to a variety of the Great Planes extrudedaluminum
Easy-Touch Bar Sanders. There is a wide selection of
lengths from which to choose.
I recommend purchasing quite a few of the 11-inch-long Bar
Sanders (part GPMR6170) and at least one or two of the longer
lengths for sanding sheeted foam wings. There is a 22-inch
(GPMR6172), a 33-inch (GPMR6174), and a 44-inch (GPMR6176).
I have a large collection of the 11-inch bars and several of the
longer ones, and I have fitted them with a variety of grits of sandpaper.
I use them until the paper starts to dull, and then I replace the paper on
all of them at one time.
It usually takes the better part of a morning to change the paper on
all of my sanding blocks, but the result is that I always have sharp
tools.
Say no to clutter. A block of EPS (expanded polystyrene) foam can
be made into a handy holder and organizer for needle files and
other small hand tools.
09sig4x_00MSTRPG.QXD 7/23/10 10:23 AM Page 118
I use 3M Super 77 spray adhesive to
attach the sandpaper to the aluminum blocks.
I apply the adhesive to the back of the paper
and let it get tacky. Then I place the sanding
block facedown on the paper against a clean,
flat surface, and press hard to make sure that
the sandpaper is attached completely to the
flat surface of the sanding bar.
Then I roll the edges of the sanding bar to
make the sandpaper conform to the edges.
This prevents the paper from gouging my
balsa parts when I use the bar. I trim the
edges against the side of the block with a
single-edge razor blade and reroll the edges
again, just to be sure.
To remove the sandpaper when it has
worn out, lay the blocks in a shallow bath of
mineral spirits for a few minutes. I use a
shallow cookie sheet for this, and I leave it
outside while the sandpaper delaminates from
the block. (This cookie sheet is a dedicated
shop item and is never used for cookie
making.) I wipe the surface of the sanding
bars clean with a fresh paper towel, and they
are ready to be resurfaced.
For finishing purposes, foam-backed
sanding blocks are the ticket. They are soft
enough to not dent anything, but they are
supportive enough to allow the surface to be
sanded smooth and flat.
I cut a piece of 1/2-inch-thick foam that is
the exact size of a full sheet of sandpaper, and
then I attach the sandpaper to the foam
backing. I used to use 3M Formula 77 for
this, but the formula has been changed and
now it (or the solvents in it) will attack the
foam. You can use one of the new
polyurethane glues instead, or even a thin coat
of epoxy.
The curing time before use will be longer,
so make several sheets at one time and slice
the size of block you need from one sheet.
You can cut tiny blocks to do detail work or
longer blocks to sand large areas.
Another great sanding tool is an industrialgrade
(professional grade?) emery board.
These can be purchased in several grits, and
some are available with different grits on each
side.
These boards, or “sanding sticks,” are 7
inches long and backed with Mylar. I get mine
from See Temp, but you can also find them at
beauty-supply stores or Web sites. Once you
try emery boards, you will probably never be
able to—or want to—build without them.
Files: Get a set of good-quality files. You will
need a flat file that is approximately 3/4 inch
wide, a half-round file, and several round, or
rat-tail, files. It is also a good idea to purchase
a set of high-quality needle files for fine work.
You will at least need a round and a threecornered
needle file.
Keep your eyes open at tool stores for
specials on files, and add to your collection.
You will find uses for them in time.
To store my needle files—and various
other small hand tools—and have them ready
at a moment’s notice for use in building, I
have a block of foam with a grid pattern
drawn on the top surface. At each grid
intersection I punched a hole that accepts a
file, screwdriver, spinner wrench, etc.
This “organizer” makes it much easier to
find the necessary tool and retrieve it quickly.
It also keeps the bench neat and free of clutter.
I am out of space again and have not yet
discussed the most useful and amazing line of
sanding and filing tools. I’ll keep you in
suspense about these until next time.
Until then, fly Stunt! MA
Edition: Model Aviation - 2010/09
Page Numbers: 118,119,120
118 MODEL AVIATION
The most important tool in the workshop
[[email protected]]
Control Line Aerobatics Bob Hunt
Purchase a selection of grits and types of sandpaper. A variety
helps with progress when building a model. Bob prefers the new
“no clog” sandpapers.
Great Planes sells a variety of extruded-aluminum sanding bars.
Purchase several of these in an assortment of lengths and fit them
with a range of grits of sandpaper.
NO TOOL IS more valuable to me in the shop than sandpaper.
That’s a strong statement, I know, and there are so many important
and useful tools for modeling that it might even seem a bit arrogant.
But it’s true.
In the last column I promised to continue the shop-stocking thread
I am on by covering sanding and filing tools. I could write a fairly
good-sized book on the subject of sanding alone, but here I’ll try to
define the minimums needed and augment that list later.
If it’s true that “God is in the details,” then sandpaper is a divine
material. Sanding technique is what separates the outstanding models
from the okay-looking models. Having the appropriate sanding and
filing tools and knowing how to use them is where the art of this
hobby—at least as far as building is concerned—lies.
For our purposes, we should have a broad selection of sandpaper
types and grits. For woodworking purposes I use and recommend one
of the new clog-resistant sandpapers. I’ve purchased them from
Norton, 3M, and Ace Hardware, and I have found all of them to work
well for sanding balsa wood.
The Norton brand is called “3X” paper, the 3M brand is
“Sandblaster,” and Ace simply calls it “Bare Wood Sandpaper.” All of
these come in a wide variety of grits, and I recommend that you
purchase a sleeve each of 400, 320, 220, 150, and 80. You will find
uses for all of them when building—trust me.
When you get to the finishing stages, you will also need a selection
of Silicon Carbide sandpaper. This type is used for wet sanding. The
grits you will most likely need range from 1,200 to 400. Again,
purchase a sleeve of each.
You will perform most sanding with either a block or some other
shape of platen. Resist the urge to do this work using your fingers as
backing for sandpaper; the result will be an uneven surface that will
look “wavy” when you apply the finish.
You can make sanding blocks from a variety of materials. Normal
woodworking blocks can be made from 2- to 21/2-inch-wide by 11-
inch-long (the normal length of the sandpaper you will buy) by 1/2- to
3/4-inch-thick pieces of Medium-Density Fiberboard (MDF). These
can be cut out on a band saw.
If you opt to make sanding blocks in this manner, be certain to
slightly chamfer the edges of the blocks so that they will not “dig” into
the balsa parts on which you will be using them.
You are not constrained to making blocks that are the full length of
the sandpaper. You will probably need to make many custom sanding
blocks in numerous shapes and sizes, to accommodate specific
building needs.
This is where the modeler’s natural engineering talents come into
play. Be creative in visualizing what type of sanding tool you need for
a specific purpose, and then craft that part accordingly.
Dowels are very useful in creating sanding tools for concave areas
such as fillets. Soft foam, such as 1-pound-per-cubic-foot expanded
polystyrene, as is used for our foam wings, can be cut into various
useful shapes and employed as sanding blocks.
The advantage is that the foam will crush if it is pushed into a
corner or fillet, and it will not dent or ding your model. I use foambacked
sanding blocks for a multitude of model building and
finishing-sanding chores.
Lately I’ve been lazy about making my own generic wood sanding
blocks and have switched to a variety of the Great Planes extrudedaluminum
Easy-Touch Bar Sanders. There is a wide selection of
lengths from which to choose.
I recommend purchasing quite a few of the 11-inch-long Bar
Sanders (part GPMR6170) and at least one or two of the longer
lengths for sanding sheeted foam wings. There is a 22-inch
(GPMR6172), a 33-inch (GPMR6174), and a 44-inch (GPMR6176).
I have a large collection of the 11-inch bars and several of the
longer ones, and I have fitted them with a variety of grits of sandpaper.
I use them until the paper starts to dull, and then I replace the paper on
all of them at one time.
It usually takes the better part of a morning to change the paper on
all of my sanding blocks, but the result is that I always have sharp
tools.
Say no to clutter. A block of EPS (expanded polystyrene) foam can
be made into a handy holder and organizer for needle files and
other small hand tools.
09sig4x_00MSTRPG.QXD 7/23/10 10:23 AM Page 118
I use 3M Super 77 spray adhesive to
attach the sandpaper to the aluminum blocks.
I apply the adhesive to the back of the paper
and let it get tacky. Then I place the sanding
block facedown on the paper against a clean,
flat surface, and press hard to make sure that
the sandpaper is attached completely to the
flat surface of the sanding bar.
Then I roll the edges of the sanding bar to
make the sandpaper conform to the edges.
This prevents the paper from gouging my
balsa parts when I use the bar. I trim the
edges against the side of the block with a
single-edge razor blade and reroll the edges
again, just to be sure.
To remove the sandpaper when it has
worn out, lay the blocks in a shallow bath of
mineral spirits for a few minutes. I use a
shallow cookie sheet for this, and I leave it
outside while the sandpaper delaminates from
the block. (This cookie sheet is a dedicated
shop item and is never used for cookie
making.) I wipe the surface of the sanding
bars clean with a fresh paper towel, and they
are ready to be resurfaced.
For finishing purposes, foam-backed
sanding blocks are the ticket. They are soft
enough to not dent anything, but they are
supportive enough to allow the surface to be
sanded smooth and flat.
I cut a piece of 1/2-inch-thick foam that is
the exact size of a full sheet of sandpaper, and
then I attach the sandpaper to the foam
backing. I used to use 3M Formula 77 for
this, but the formula has been changed and
now it (or the solvents in it) will attack the
foam. You can use one of the new
polyurethane glues instead, or even a thin coat
of epoxy.
The curing time before use will be longer,
so make several sheets at one time and slice
the size of block you need from one sheet.
You can cut tiny blocks to do detail work or
longer blocks to sand large areas.
Another great sanding tool is an industrialgrade
(professional grade?) emery board.
These can be purchased in several grits, and
some are available with different grits on each
side.
These boards, or “sanding sticks,” are 7
inches long and backed with Mylar. I get mine
from See Temp, but you can also find them at
beauty-supply stores or Web sites. Once you
try emery boards, you will probably never be
able to—or want to—build without them.
Files: Get a set of good-quality files. You will
need a flat file that is approximately 3/4 inch
wide, a half-round file, and several round, or
rat-tail, files. It is also a good idea to purchase
a set of high-quality needle files for fine work.
You will at least need a round and a threecornered
needle file.
Keep your eyes open at tool stores for
specials on files, and add to your collection.
You will find uses for them in time.
To store my needle files—and various
other small hand tools—and have them ready
at a moment’s notice for use in building, I
have a block of foam with a grid pattern
drawn on the top surface. At each grid
intersection I punched a hole that accepts a
file, screwdriver, spinner wrench, etc.
This “organizer” makes it much easier to
find the necessary tool and retrieve it quickly.
It also keeps the bench neat and free of clutter.
I am out of space again and have not yet
discussed the most useful and amazing line of
sanding and filing tools. I’ll keep you in
suspense about these until next time.
Until then, fly Stunt! MA
