Patent Pending
L.Douglas, LLC
L.Douglas, LLC
Circular saws have been around for ages. Actually for over two hundred years. No one knows who invented the
circular blade itself, but I would guess the idea came out of a saw mill situated beside a river where some clever
worker concluded it would be easier to convert the rotating input of a water wheel to something other than a
reciprocating large tooth saw blade. Maybe his best buddy was a black smith who fashioned the first blade for him
and before you knew it, someone, hopefully those two prolific workers, were in the business of making saw mill
circular blades. By the time electric motors came around, tooth profiles and tooth setting were already heading
into it’s second one hundred years.
That leads me into wondering where the term miter gauge came from instead of a name more applicable to use
like cross cutting fence. We all have two or three of them in our shops and until only recently I never called them
miter gauges. Again, speculation is at work here as to where they came from and why they are called miter
gauges. Even miter maker makes more sense from a literal point of view. Maybe a machinist configured the first
table saw, a circular saw blade under and through a table powered by an early abandoned electric motor he
found in a trash deemed unlikely to be no longer useful for anything. He designed his saw table so it could be
easily moved about, especially to the big house he would buy after making thousands of dollars with his invention.
Maybe his motivation came from cutting the boards by hand for making the crates for shipping his precision
turned flywheels? Maybe he was into only one hours use of his new concept when he realized it was difficult to
push a board through a moving saw by hand without binding the board, a challenge that could easily result in an
unexpected accident. I would bet his first prototype had a table made out of wood and it wasn’t too difficult to
create a sliding guide of some kind that ran parallel to the blade, allowing him to push the board through keeping
it on a true path. He probably made this guide out of an old square he had laying around. That’s when he realized
he could probably push the board through at an angle if he only had a true means for doing so. Being a
machinist, a miter gauge came to mind that he had in his tool box. This was nothing more than two pivoting legs
with a protractor that was used for measuring angles. The rest is more speculation. But why didn’t they call it a
cross cutting fence because when relative to purely function, that’s what we use to push our material through a
saw blade when needing to cross cut. To call it a miter bugs me a bit. To call it a miter gauge bugs me a bit more.
But within all true democracies, the majority rules and if the world knows what we are referring to when we say
“miter gauge”, then that’s what it should be called.
Yes, miter gauges have been around for one hundred years or so. Maybe earlier in the form of a sled used to
cross cut lumber in one of those riverside mills. I can go back sixty years with one of mine, a Craftsman that
belonged to my father, and it doesn’t look any different than the one that came with my recently purchased ten
inch large bed table saw. In fact, they not only look the same but are made the same. A miter bar, and why aren’t
all miter slots the same width by the way, is the guiding member of what’s mounted to it. What’s mounted to it is a
cast protractor with a circular slot and a face high enough and barely long enough to square a board while it is
being pushed through the saw blade. As we all know, the circular slot allows us to rotate the face at least plus or
minus 45 degrees relative to the saw blade. What keeps the protractor set to the desired angle is a cylindrical
handle that tightens against the circular slot and also serves as a push handle. That’s what they are now, that’s
what they were fifty years ago and probably pretty close to what they were one hundred years ago as well. The
concept will remain solid because in my opinion, it is pure. However, improving any concept is a worthwhile effort
for anyone.
How accurate wood cutting should be is what determines how accurate the miter gauge must be. After market
miter gauges suggest the process must be more accurate than stock miter gauges that come with the purchase of
table saws suggest it should be. If one table saw company controlled the market, stock miter gauges might be as
good as the saws they come with. But there are many table saw manufacturers and cost cutting is always part of
the competition strategy. Also, maybe the miter gauge after market has become so clever that saw manufacturer’s
don’t want to compete with them knowing their serious customers will eventually purchase an after market miter
gauge that fits their expectations and needs. Knowing the miter face is always set at zero degrees when picked up
for use and can be easily set at any other needed angle with confidence is the rational for all after market miter
gauges. I’m not sure it’s can’t be for the saw manufacturers as well. Maybe it is and maybe many customers get
along just fine with the miter gauge that came with their table saw.
Why is the Protractor Miter Gauge any better than what comes with the purchase of a table saw? I have at least
four of them, the one I told you about earlier is over a half century old and isn’t any different than the one that
came with my table saw I purchased only recently. The Protractor Miter Gauge is better in many respects and
naturally it will cost more than the no frills standard miter talked about so far. It’s better in concept function and
feel and I am happy to elaborate more on how I feel protractor miter gauges can be improved and how this unique
design will compete with all after market miter gauges.
I always fumbled with the means of keeping the stops of my miter gauges set accurately. Some have an adjustable
stop for both zero degrees and both forty five degree positions. You might wonder why there isn't only one
adjustment and two accurately cast surfaces 45 degrees apart. They never seemed reliable to the point I could
trust them for any period of time. It seems every time I started a project, I would have to reset my miter gauge
stops, something inside telling me I should. I never questioned why I had to reset them over and over again, only
wanting to get on with my project knowing the miter gauge would work fine as long as I checked it occasionally.
If these standard miter gauges did have only one adjustment, it should not be one that gets banged into every
time the protractor is rotated, knocking or wearing it out of adjustment. Also, the pointer that you must rely on
when setting angles between 0 degrees and 45 degrees should be much more than a piece of sheet metal
screwed in place with one screw. With no detents or other means signaling you when you are at 15 or 30 degrees,
counting on a little pointer may not be wise.
On occasion I bolted a fence extender to the miter gauge face, allowing it to extend right up to the saw blade. This
worked fine until I rotated the fence for a forty five degree cut. The extension board that was originally close to the
blade ended up a couple of inches away from at the extreme settings. A fence should be closer to the blade than
that, especially when cutting pieces a size that will have more overhanging the fence than secured in front of it.
And again, at these extreme positions, I would have to reconfirm my 45 degree stop as well. There is no way I
was going to assume the stop was still accurate because in the past I have had to reset it just to cut a little beyond
45 degrees to match a previous cut that was just a little bit less than 45 degree for reasons unknown but
suspected. And as we all know, too much of that results in one miter surface being longer than the other.
I lived with this type of miter gauge for many years, again taking its limited usefulness as a given because my
father had one just like it, maybe more robust, and my high school shop had a half dozen miter gauges
manufactured around the same basic concept. And while using my miter gauges over the years, I wondered why I
had to guess, or line up calibration lines to the best of my ability, for an angle other than zero degree or forty five
degrees. This is especially difficult with small graduation marks with spacing being a function of the size of the
radius, in this case a small one. I always did so knowing I would have to make a test cut on scrap wood first. I knew
that if my zero degree setting was off, which it of often was, my thirty degree setting would be off as well. Even if
my zero degree setting was right on, I would still be guessing at where the real thirty degree setting was.
Why can’t these miter gauges have indexing holes I often asked myself. Even every five degrees is better than
none. All miter gauges could have at least that I thought, but the economics of manufacturing might not permit it.
Cast detents, slots or whatever means that might be chosen would have to be machined in after the casting
process to get any kind of accuracy. Stamping them out might be a better alternative, but that takes heavy tooling
if the thickness of the sheet metal approaches plate dimensions. A protractor miter gauge having a detent every
one degree might have to have a very large radius to realistically incorporate a reliable indexing design. So large
in fact it would swing into the line of the saw blade. I sketched dozens of concepts that didn’t employ a large
protractor and modeled a couple our of wood. Regardless of the attributes of any of the non protractor desgins, I
always came back to a large radius protractor.
A protractor design places all the geometry on one part. This makes it a sure thing of having undisputed accuracy
between extreme settings, depending how it is manufactured. The larger the radius, the more accurate the
protractor becomes. Studying other means of tying the miter fence to the miter slide bar other than a protractor
scale, I became weary of the tolerances in the additional parts and their effect on settings other than zero.
Controlling these tolerances was something I didn’t want to get into. A computer controlled machine can
guarantee the spacing of the protractor between zero degrees and forty five degrees and the spacing will always
be dead on. A mechanism can’t always provide that. If the parts are too short or too long and zero degrees could
is set perfectly, the forty five degree setting may be something other than forty five degrees. Not by much, but two
forty five degree cuts that are not right on are twice as bad when forming the miter joint. I liked the simplicity and
awareness of accuracy a protractor suggests after limiting my thinking around the merits of the life long standard,
the protractor. I liked the idea of having a large enough radius to mechanically index every one degree without the
error that occurs when lining up two lines. I liked the simple idea of adding a second arc or holes for one half
degree indexing.
I liked the thought of a one time adjustment that doesn’t get knocked out of place during normal use, because
there shouldn't be a slammed into stop, just the human input of indexing to the correct hole. I zeroed in on a bolt
with locking nuts for the adjustment knowing that was a proven concept used long before any of us were around.
And the second prototype showed how great it felt to simply give the push handle a little twist, press the indexing
lever and swing the protractor to the degree setting you want and let the lever and pin snap into place. As rigid as
this is, it becomes more robust when tightening down the handle before pushing. Tightening down the handle,
discovered during testing of the second prototype, didn’t disturb the setting because the indexing pin had the
protractor securely held in place.
I liked having a fence that could extend as close to the blade as I like under all angular settings. Many wood
workers like to easily attach a sacrificial fence to the product fence and that should be an easy thing to do. A
fence stop is important to a lot of wood workers. Not only for repeated cuts, but also to help keep the board from
slipping relative to the fence when making miter cuts.
I can be convinced of many things which is a good thing. But it’s a better thing to be able to be unconvinced by
anyone that wants to take the time to communicate with me. We all learn from each other, and when that stops it’s
time to move into a cave. For a long while, both in time and money, I was convinced a forty five degree circle
segment for a miter gauge would provide enough input for all cuts that are generally made on a table saw. Keep
in mind, the driving force behind the rational was having enough circumference as a result of the large radius to
machine 1/8 diameter holes every one degree. The displacement of a large radius protractor is limited because of
the saw blade restricting the area the protractor can work in.
Market testing generates valuable information for products like a miter gauge. However, I feel there are at least as
many downside factors to market testing as upside. Evaluating data from input by less than objective people who
have already made up their minds can be difficult but still fruitful. Input from people who only want to make the
product better is invaluable as long as it doesn’t come from a friend or relative who is being cautious not to hurt
your feelings. The limited value of a forty five degree protector segment became obvious to me from forum input
on the Internet, and not use tests by myself in my shop. This was an error on my part, especially when discovering
after the fact that wood workers don't want to flip their stock over for opposite end miter cuts because doing so
introduces splintering on one side of the stock. Also many molding profiles do not allow the flipping of the stock for
opposite end cutting. More hours using the prototypes may have allowed me to rediscover these deficiencies
beforehand.
Changing the Protractor Miter Gauge from a 50 degree segment to a 100 degree segment was at first a
challenge, but one that turned obvious. Arranging the cross bar in the opposite direction allowed a pivot for the
protractor to be further away from the blade than if the protractor was mounted directly on the miter bar. One
problem with this was the fence now swings further away from the blade when the protractor is set at 45 degrees.
Incorporating a fence that was not limited in it’s travel was the answer to that problem. Moving the pivot away from
the blade allows a much larger radius than typical protractors, thus more indexing holes. Two and a half degree
spacing is ideal for many reasons. Being able to set the protractor between holes is easy as well because of the
large space between one degree graduations.
Miter bar slop is one more reason to justify a need for industrial standards. What could be easier than machining,
now molding in a lot of cases, a .755 wide slot in the table saw top from one manufacturer to the next. Imports
would have to abide also or they wouldn’t be allowed off of the boat. That would allow standard bar stock sizes,
including tolerances, to comfortably ride within them with out a lot of play. Naturally, the longer the bar, the less
angular play. Adjusting a bar’s width is a challenge. It’s difficult to strive for zero clearance, because the width of a
slot varies withing itself. Two thousands of an inch is a tough tolerance when machining cast iron. Adjusting the
miter bar to zero clearance will work fine within part of the slot, but not all of it. I found adjusting screws that
pushed one side of the bar against the slot while the screw tip ran on the other offered a bumpy ingress and
egress of the screws relative to the far end of the table. Designs that expand the width of the bar by turning a
screw in or out work marvelously and it’s clear why the concept is part of that particular miter gauge patent. I
thought tightening a screw head against the beveled inside edges of a split washer would be a great way of doing
it and so didn’t someone else who beat me to the idea. An eccentric disk works wonderfully and is large enough in
diameter not to be noticed when traveling into and out of the table saw slot. A Delrin disk will hold up for years,
and if it wears, the disk simply has to be turned a few degrees. It's also very easy to readjust the eccentric disk if
bringing the miter to a second saw bed for use. I’m not sure what the acceptable clearances are for a miter bar
and the relative table saw slot. It has a lot to do with when every thing else within the miter is perfect, a little bit of
daylight can still be seen within the miter cuts when the members are set at a perfect 90 degrees. I do know that
zero slop is not possible unless the width of the slots are perfectly uniform and that the minimum amount of
practical slop that can be tolerated is best.
In my opinion, the Protractor Miter Gauge is a vast improvement over small radius protractors. CNC machining is
the true manufacturing method for precise instruments and I will engage in constructive conversation about that
with anyone. Precise instruments are not made in mass production. They are made in low volume production
where manufacturing variables are at a minimum and attention can be paid to every part, not every 100th part.
An argument can not be made against having all the geometry on one piece of stock and it can't be any cleaner
than that unless the stock happens to be less than robust. The Protractor Miter Gauge is robust being made from
quality materials. It is simple in design and that alone lends itself to precision.....Thank you....LD
circular blade itself, but I would guess the idea came out of a saw mill situated beside a river where some clever
worker concluded it would be easier to convert the rotating input of a water wheel to something other than a
reciprocating large tooth saw blade. Maybe his best buddy was a black smith who fashioned the first blade for him
and before you knew it, someone, hopefully those two prolific workers, were in the business of making saw mill
circular blades. By the time electric motors came around, tooth profiles and tooth setting were already heading
into it’s second one hundred years.
That leads me into wondering where the term miter gauge came from instead of a name more applicable to use
like cross cutting fence. We all have two or three of them in our shops and until only recently I never called them
miter gauges. Again, speculation is at work here as to where they came from and why they are called miter
gauges. Even miter maker makes more sense from a literal point of view. Maybe a machinist configured the first
table saw, a circular saw blade under and through a table powered by an early abandoned electric motor he
found in a trash deemed unlikely to be no longer useful for anything. He designed his saw table so it could be
easily moved about, especially to the big house he would buy after making thousands of dollars with his invention.
Maybe his motivation came from cutting the boards by hand for making the crates for shipping his precision
turned flywheels? Maybe he was into only one hours use of his new concept when he realized it was difficult to
push a board through a moving saw by hand without binding the board, a challenge that could easily result in an
unexpected accident. I would bet his first prototype had a table made out of wood and it wasn’t too difficult to
create a sliding guide of some kind that ran parallel to the blade, allowing him to push the board through keeping
it on a true path. He probably made this guide out of an old square he had laying around. That’s when he realized
he could probably push the board through at an angle if he only had a true means for doing so. Being a
machinist, a miter gauge came to mind that he had in his tool box. This was nothing more than two pivoting legs
with a protractor that was used for measuring angles. The rest is more speculation. But why didn’t they call it a
cross cutting fence because when relative to purely function, that’s what we use to push our material through a
saw blade when needing to cross cut. To call it a miter bugs me a bit. To call it a miter gauge bugs me a bit more.
But within all true democracies, the majority rules and if the world knows what we are referring to when we say
“miter gauge”, then that’s what it should be called.
Yes, miter gauges have been around for one hundred years or so. Maybe earlier in the form of a sled used to
cross cut lumber in one of those riverside mills. I can go back sixty years with one of mine, a Craftsman that
belonged to my father, and it doesn’t look any different than the one that came with my recently purchased ten
inch large bed table saw. In fact, they not only look the same but are made the same. A miter bar, and why aren’t
all miter slots the same width by the way, is the guiding member of what’s mounted to it. What’s mounted to it is a
cast protractor with a circular slot and a face high enough and barely long enough to square a board while it is
being pushed through the saw blade. As we all know, the circular slot allows us to rotate the face at least plus or
minus 45 degrees relative to the saw blade. What keeps the protractor set to the desired angle is a cylindrical
handle that tightens against the circular slot and also serves as a push handle. That’s what they are now, that’s
what they were fifty years ago and probably pretty close to what they were one hundred years ago as well. The
concept will remain solid because in my opinion, it is pure. However, improving any concept is a worthwhile effort
for anyone.
How accurate wood cutting should be is what determines how accurate the miter gauge must be. After market
miter gauges suggest the process must be more accurate than stock miter gauges that come with the purchase of
table saws suggest it should be. If one table saw company controlled the market, stock miter gauges might be as
good as the saws they come with. But there are many table saw manufacturers and cost cutting is always part of
the competition strategy. Also, maybe the miter gauge after market has become so clever that saw manufacturer’s
don’t want to compete with them knowing their serious customers will eventually purchase an after market miter
gauge that fits their expectations and needs. Knowing the miter face is always set at zero degrees when picked up
for use and can be easily set at any other needed angle with confidence is the rational for all after market miter
gauges. I’m not sure it’s can’t be for the saw manufacturers as well. Maybe it is and maybe many customers get
along just fine with the miter gauge that came with their table saw.
Why is the Protractor Miter Gauge any better than what comes with the purchase of a table saw? I have at least
four of them, the one I told you about earlier is over a half century old and isn’t any different than the one that
came with my table saw I purchased only recently. The Protractor Miter Gauge is better in many respects and
naturally it will cost more than the no frills standard miter talked about so far. It’s better in concept function and
feel and I am happy to elaborate more on how I feel protractor miter gauges can be improved and how this unique
design will compete with all after market miter gauges.
I always fumbled with the means of keeping the stops of my miter gauges set accurately. Some have an adjustable
stop for both zero degrees and both forty five degree positions. You might wonder why there isn't only one
adjustment and two accurately cast surfaces 45 degrees apart. They never seemed reliable to the point I could
trust them for any period of time. It seems every time I started a project, I would have to reset my miter gauge
stops, something inside telling me I should. I never questioned why I had to reset them over and over again, only
wanting to get on with my project knowing the miter gauge would work fine as long as I checked it occasionally.
If these standard miter gauges did have only one adjustment, it should not be one that gets banged into every
time the protractor is rotated, knocking or wearing it out of adjustment. Also, the pointer that you must rely on
when setting angles between 0 degrees and 45 degrees should be much more than a piece of sheet metal
screwed in place with one screw. With no detents or other means signaling you when you are at 15 or 30 degrees,
counting on a little pointer may not be wise.
On occasion I bolted a fence extender to the miter gauge face, allowing it to extend right up to the saw blade. This
worked fine until I rotated the fence for a forty five degree cut. The extension board that was originally close to the
blade ended up a couple of inches away from at the extreme settings. A fence should be closer to the blade than
that, especially when cutting pieces a size that will have more overhanging the fence than secured in front of it.
And again, at these extreme positions, I would have to reconfirm my 45 degree stop as well. There is no way I
was going to assume the stop was still accurate because in the past I have had to reset it just to cut a little beyond
45 degrees to match a previous cut that was just a little bit less than 45 degree for reasons unknown but
suspected. And as we all know, too much of that results in one miter surface being longer than the other.
I lived with this type of miter gauge for many years, again taking its limited usefulness as a given because my
father had one just like it, maybe more robust, and my high school shop had a half dozen miter gauges
manufactured around the same basic concept. And while using my miter gauges over the years, I wondered why I
had to guess, or line up calibration lines to the best of my ability, for an angle other than zero degree or forty five
degrees. This is especially difficult with small graduation marks with spacing being a function of the size of the
radius, in this case a small one. I always did so knowing I would have to make a test cut on scrap wood first. I knew
that if my zero degree setting was off, which it of often was, my thirty degree setting would be off as well. Even if
my zero degree setting was right on, I would still be guessing at where the real thirty degree setting was.
Why can’t these miter gauges have indexing holes I often asked myself. Even every five degrees is better than
none. All miter gauges could have at least that I thought, but the economics of manufacturing might not permit it.
Cast detents, slots or whatever means that might be chosen would have to be machined in after the casting
process to get any kind of accuracy. Stamping them out might be a better alternative, but that takes heavy tooling
if the thickness of the sheet metal approaches plate dimensions. A protractor miter gauge having a detent every
one degree might have to have a very large radius to realistically incorporate a reliable indexing design. So large
in fact it would swing into the line of the saw blade. I sketched dozens of concepts that didn’t employ a large
protractor and modeled a couple our of wood. Regardless of the attributes of any of the non protractor desgins, I
always came back to a large radius protractor.
A protractor design places all the geometry on one part. This makes it a sure thing of having undisputed accuracy
between extreme settings, depending how it is manufactured. The larger the radius, the more accurate the
protractor becomes. Studying other means of tying the miter fence to the miter slide bar other than a protractor
scale, I became weary of the tolerances in the additional parts and their effect on settings other than zero.
Controlling these tolerances was something I didn’t want to get into. A computer controlled machine can
guarantee the spacing of the protractor between zero degrees and forty five degrees and the spacing will always
be dead on. A mechanism can’t always provide that. If the parts are too short or too long and zero degrees could
is set perfectly, the forty five degree setting may be something other than forty five degrees. Not by much, but two
forty five degree cuts that are not right on are twice as bad when forming the miter joint. I liked the simplicity and
awareness of accuracy a protractor suggests after limiting my thinking around the merits of the life long standard,
the protractor. I liked the idea of having a large enough radius to mechanically index every one degree without the
error that occurs when lining up two lines. I liked the simple idea of adding a second arc or holes for one half
degree indexing.
I liked the thought of a one time adjustment that doesn’t get knocked out of place during normal use, because
there shouldn't be a slammed into stop, just the human input of indexing to the correct hole. I zeroed in on a bolt
with locking nuts for the adjustment knowing that was a proven concept used long before any of us were around.
And the second prototype showed how great it felt to simply give the push handle a little twist, press the indexing
lever and swing the protractor to the degree setting you want and let the lever and pin snap into place. As rigid as
this is, it becomes more robust when tightening down the handle before pushing. Tightening down the handle,
discovered during testing of the second prototype, didn’t disturb the setting because the indexing pin had the
protractor securely held in place.
I liked having a fence that could extend as close to the blade as I like under all angular settings. Many wood
workers like to easily attach a sacrificial fence to the product fence and that should be an easy thing to do. A
fence stop is important to a lot of wood workers. Not only for repeated cuts, but also to help keep the board from
slipping relative to the fence when making miter cuts.
I can be convinced of many things which is a good thing. But it’s a better thing to be able to be unconvinced by
anyone that wants to take the time to communicate with me. We all learn from each other, and when that stops it’s
time to move into a cave. For a long while, both in time and money, I was convinced a forty five degree circle
segment for a miter gauge would provide enough input for all cuts that are generally made on a table saw. Keep
in mind, the driving force behind the rational was having enough circumference as a result of the large radius to
machine 1/8 diameter holes every one degree. The displacement of a large radius protractor is limited because of
the saw blade restricting the area the protractor can work in.
Market testing generates valuable information for products like a miter gauge. However, I feel there are at least as
many downside factors to market testing as upside. Evaluating data from input by less than objective people who
have already made up their minds can be difficult but still fruitful. Input from people who only want to make the
product better is invaluable as long as it doesn’t come from a friend or relative who is being cautious not to hurt
your feelings. The limited value of a forty five degree protector segment became obvious to me from forum input
on the Internet, and not use tests by myself in my shop. This was an error on my part, especially when discovering
after the fact that wood workers don't want to flip their stock over for opposite end miter cuts because doing so
introduces splintering on one side of the stock. Also many molding profiles do not allow the flipping of the stock for
opposite end cutting. More hours using the prototypes may have allowed me to rediscover these deficiencies
beforehand.
Changing the Protractor Miter Gauge from a 50 degree segment to a 100 degree segment was at first a
challenge, but one that turned obvious. Arranging the cross bar in the opposite direction allowed a pivot for the
protractor to be further away from the blade than if the protractor was mounted directly on the miter bar. One
problem with this was the fence now swings further away from the blade when the protractor is set at 45 degrees.
Incorporating a fence that was not limited in it’s travel was the answer to that problem. Moving the pivot away from
the blade allows a much larger radius than typical protractors, thus more indexing holes. Two and a half degree
spacing is ideal for many reasons. Being able to set the protractor between holes is easy as well because of the
large space between one degree graduations.
Miter bar slop is one more reason to justify a need for industrial standards. What could be easier than machining,
now molding in a lot of cases, a .755 wide slot in the table saw top from one manufacturer to the next. Imports
would have to abide also or they wouldn’t be allowed off of the boat. That would allow standard bar stock sizes,
including tolerances, to comfortably ride within them with out a lot of play. Naturally, the longer the bar, the less
angular play. Adjusting a bar’s width is a challenge. It’s difficult to strive for zero clearance, because the width of a
slot varies withing itself. Two thousands of an inch is a tough tolerance when machining cast iron. Adjusting the
miter bar to zero clearance will work fine within part of the slot, but not all of it. I found adjusting screws that
pushed one side of the bar against the slot while the screw tip ran on the other offered a bumpy ingress and
egress of the screws relative to the far end of the table. Designs that expand the width of the bar by turning a
screw in or out work marvelously and it’s clear why the concept is part of that particular miter gauge patent. I
thought tightening a screw head against the beveled inside edges of a split washer would be a great way of doing
it and so didn’t someone else who beat me to the idea. An eccentric disk works wonderfully and is large enough in
diameter not to be noticed when traveling into and out of the table saw slot. A Delrin disk will hold up for years,
and if it wears, the disk simply has to be turned a few degrees. It's also very easy to readjust the eccentric disk if
bringing the miter to a second saw bed for use. I’m not sure what the acceptable clearances are for a miter bar
and the relative table saw slot. It has a lot to do with when every thing else within the miter is perfect, a little bit of
daylight can still be seen within the miter cuts when the members are set at a perfect 90 degrees. I do know that
zero slop is not possible unless the width of the slots are perfectly uniform and that the minimum amount of
practical slop that can be tolerated is best.
In my opinion, the Protractor Miter Gauge is a vast improvement over small radius protractors. CNC machining is
the true manufacturing method for precise instruments and I will engage in constructive conversation about that
with anyone. Precise instruments are not made in mass production. They are made in low volume production
where manufacturing variables are at a minimum and attention can be paid to every part, not every 100th part.
An argument can not be made against having all the geometry on one piece of stock and it can't be any cleaner
than that unless the stock happens to be less than robust. The Protractor Miter Gauge is robust being made from
quality materials. It is simple in design and that alone lends itself to precision.....Thank you....LD
The heart of any miter gauge evolves from the
mechanical design of the structure that locates the miter
face, the surface that interfaces with the project stock.
The design should be a no nonsense robust means that
not only precisely locates the fence for exact cross cuts,
but every angle that follows for precise miter cuts in
either direction as well.
mechanical design of the structure that locates the miter
face, the surface that interfaces with the project stock.
The design should be a no nonsense robust means that
not only precisely locates the fence for exact cross cuts,
but every angle that follows for precise miter cuts in
either direction as well.
The Protractor Miter Gauge is optimized and
assembled for use on the left side of the saw
blade. If the distance from the saw blade to
the miter slot of the right side of the table
allows, the Protractor Miter Gauge can be
reassembled for use on that side of the table.
assembled for use on the left side of the saw
blade. If the distance from the saw blade to
the miter slot of the right side of the table
allows, the Protractor Miter Gauge can be
reassembled for use on that side of the table.
Pushing down the lever at
brace releases the pin
Pushing down the lever at
from the protractor holes
and letting up resets the
pin.
The protractor can be
easily set and held
between holes to the
large easy to view scale.
The protractor can be
rotated plus or minus 50
degrees.
brace releases the pin
Pushing down the lever at
from the protractor holes
and letting up resets the
pin.
The protractor can be
easily set and held
between holes to the
large easy to view scale.
The protractor can be
rotated plus or minus 50
degrees.
The fence stop slides the full length
of the fence, flips up 90 degrees out
of the way during project use and
rotates 180 degrees for non
nuisance storage when it is not
needed.
of the fence, flips up 90 degrees out
of the way during project use and
rotates 180 degrees for non
nuisance storage when it is not
needed.
Alternative length fences will be available
up to four feet long in six inch increments.
up to four feet long in six inch increments.
All of the geometry, the
protractor pivot and
indexing holes, are on one
piece of 1/4 inch thick
aluminum plate. Once the
in, the following angular
indexing holes, are on one
positions are guaranteed
positions are guaranteed
because all the geometry
because all the geometry
is accurately placed on one
is accurately placed on one
part with CNC machining.
protractor pivot and
indexing holes, are on one
piece of 1/4 inch thick
aluminum plate. Once the
in, the following angular
indexing holes, are on one
positions are guaranteed
positions are guaranteed
because all the geometry
because all the geometry
is accurately placed on one
is accurately placed on one
part with CNC machining.
The Protractor Miter Gauge may
not be a practical fit for compact
table saws. The minimum
distance from the inside of the left
hand slot to the saw blade should
be a minimum of 4 1/2 inches.
not be a practical fit for compact
table saws. The minimum
distance from the inside of the left
hand slot to the saw blade should
be a minimum of 4 1/2 inches.
Having the protractor position locked with the Indexing pin
prevents protractor slippage when tightening down the push
handle as well as freezing the location for reliable use.
prevents protractor slippage when tightening down the push
handle as well as freezing the location for reliable use.
Three easy to adjust
and tighten cams are
built into the hard
anodized aircraft
aluminum miter bar.
The gradual surfaces
make them hardly
noticeable when
entering and exiting
the table slot.
A removable "T" slot
square washer is
attached to the tip of
the miter bar.
and tighten cams are
built into the hard
anodized aircraft
aluminum miter bar.
The gradual surfaces
make them hardly
noticeable when
entering and exiting
the table slot.
A removable "T" slot
square washer is
attached to the tip of
the miter bar.
The aluminum
fence is quality "T"
Slot design with a 1
inch x 3 inch cross
section, 24 inches
long. The stop flips
to the back side of
the fence when not
needed. The fence
sliding distance is
not limited.
fence is quality "T"
Slot design with a 1
inch x 3 inch cross
section, 24 inches
long. The stop flips
to the back side of
the fence when not
needed. The fence
sliding distance is
not limited.
The Protractor Miter Gauge is CNC
machined from robust aircraft aluminum
and hard anodized. The radius of the
protractor is 6 inches, almost twice the
radial distance of most protractor miters.
This alone means added precision.
Maintaining
adjustment is always
important. The
threaded cross
brace of the patent
pending Locked "X"
Frame securely
locks your
adjustment while
unlocking provides a
gradual means of
adjustment if and
when you need.
adjustment is always
important. The
threaded cross
brace of the patent
pending Locked "X"
Frame securely
locks your
adjustment while
unlocking provides a
gradual means of
adjustment if and
when you need.
The precision machined holes
of the protractor, spaced two
and one half degrees apart on
a six inch radius, are indexed
and held with a stainless steel
dowel pin that assures
repeated performance. The
scale graduations are one
degree apart.
of the protractor, spaced two
and one half degrees apart on
a six inch radius, are indexed
and held with a stainless steel
dowel pin that assures
repeated performance. The
scale graduations are one
degree apart.
The 24 inch long fence, located at three points, easily
slides to any position with the loosening and then
tightening of the easy to reach fence clamping knob.
slides to any position with the loosening and then
tightening of the easy to reach fence clamping knob.
Exact design configuration of some images are not quite up to date from here down.
Patent Pending
L.Douglas, LLC
L.Douglas, LLC
Knowing exactly what it is and who your
customers are should always precede the large
expenditures....LMD
customers are should always precede the large
expenditures....LMD
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Thank you and always work safely...Larry