44 years - AirGraver History
by Steve Lindsay
tools are a culmination of 44 years of engraving and tool making by Frank and
Steve Lindsay. In
1975, at the age of 17, Steve began to learn hand engraving with his father
who is a watchmaker and jeweler. Frank became friends with John Rohner and James (Bruce) Meeks. At that time
he purchased John Rohner's
invention called a Gravermeister from John in Boulder Colorado. John's
invention was the world's first pneumatic engraver. John Rohner was a
supporter encouraging Steve to continue learning. Above is a book John
signed in 1977 which was an inspiration to Steve during that time.
In 1977, after graduating from high school,
Steve enrolled in the same Nebraska tech college that his father attended studying watch making.
in machine tool and die on the recommendation of John Rohner.
The college and super instructors (i.e. Alan Carter) allowed students to use
the school's machine shop for personal projects in the evening. Taking that
opportunity, Steve created several new hand pieces for the Graermeister that
he was using. The new hand pieces were palm-sized rather than long. This was
beneficial for smaller, detailed engraving as well as providing improved
control. In 1979, Frank designed an electronic circuit to
oscillate and adjust the speed of a solenoid valve. Air was run through the
valve to produce blow-pulses rather than suction-pulses. Frank made two of
the machines. Steve used the school's machines to build
various hand pieces for this adjustable positive pulse generator.
In an interview for the December, 1981 NebraskaLand magazine, Frank's machine
was mentioned and a picture of it can be seen on the back corner of the engraving bench on page five of the article.
It is the gray box in the
right back corner of the bench. The hand pieces hidden for the article
and from the public for years. At the left is a picture of three positive pulse hand
gravers made in 1979 for Frank's machine.
tool & die school, Steve continued to engrave by day while working second shift in
the tool room of a Nebraska manufacturer. After regular hours there, he used
their machine tools and continued to refine engraving tools. He also made two
positioning vises for his
father and himself for engraving under The diamond scopes used in the jewelry store. In 1980 after the tools were refined
and efficient, Steve quit the job and began full time engraving. Another friend of
Frank's, Lynton McKenzie, recommended Steve attend the knife makers' guild show
in Kansas City in 1980. He
took the top side of this
linked 9mm Browning to the show. Lynton was
at the show and took him from table to table to introduce him to knife makers and
his collectors. Knife markers such as Buster Warenski, Steve Johnson, Steve
Hoel, Ron Lake, Jim Hardenbrook and Jim Ence. were at the show. From
those introductions, knife makers and collectors gave Steve engraving jobs. (some can be seen at
www.LindsayEngraving.com ). For
the next few years, Frank made more improved hand pieces with his lathes and
milling machines that Steve then used for his engravings. In 1984 or
1985 James Meeks came by to say hello and visit. He was working on his second book then and brought along
many white plastic plates. He explained the surface was white but when cut into, the lines
showed black. He had engraved them with various scrolls and example designs.
He explained he was engraving this plastic because the engraving
photograph well for the book. After that visit Don Glaser Sr. called and said
that Meeks really enjoyed seeing the palm sized graver. It was an awkward phone call
because Steve did not show Meeks his hand piece during his visit. Steve
did receive a phone call while Meeks was visiting and he was left alone at the
bench for a short time. He must have
found the hand piece. It was interesting because after that Mr. Glaser
brought out a new smaller hand piece that had a plastic mushroom handle on the
the hand pieces they were making that were long and straight with
handle midway rather than at the end. It did not matter since Steve was
not in the tool business at that time, but only engraving for collectors.
In 1987 Frank and Steve did some engraving projects together. They produced five engraved folding knives.
Steve drew the outlines of the knife designs and Frank made and set the diamonds, and
Steve then engraved them. Frank's knives
had hidden watch screws and wedges and would come apart allowing the inside
surfaces as well as the outside ones to be engraved. The five pieces
were called Lindsay-Lindsay. The Japanese knife engraving market was strong
then and several of them went to customers and dealers in Japan selling for as
much as $40,000. Later the owner of the #5 piece contacted Steve with
the news that he had a terminal illness and wanted to sell and was asking
$110,000. It was offered for sale on the
site and was resold.
and Steve engraved a SCI Safari
Club International rifle project together. David Miller was the maker, Lynton
engraved the rifle and Steve did the accessories and a Steve Hoel folding knife
that were cased with the rifle. The piece sold at auction for
Lynton had also been engraving Gene Clark's
watches. When Lynton became sick in early 1998 he recommended to Gene that
them. Steve engraved three of Gene's watches. An improved AirGraver design
was completed while working on the second one.
That second one was auctioned at Sotherby's and sold for $62,500.
Through the years the AirGraver continued to be improved.
There is a video
of one of Gene's watch faces being engraved in the above link.
Various Lindsay AirGraver designs.
1. A Lindsay self oscillation
AirGraver piston principle was patented. It can operate with very little air
pressure or air volume. In fact, by simply blowing in it. Even attached to a toy balloon, the tool will idle. Instead of a
spring for the return or impact stroke, the device uses air pressure for both
directions. As a result, the piston always stays balanced and low or high air
pressures can be used without one side overpowering the other causing the piston
to float, which can occur with the spring-pulse designs. The patented idle of
the new design prevents jumps that sometimes occur with spring-pulse designs.
The stroke length and speed adjustment is in the bore of tool. Adjustment is
made by removing the graver and adjusting the screw at the bottom of the tool
2. A multiple controller box is shown above. Since this box required a lot of work to
manufacture, it was replaced by using either a simple toggle-routing valve on the current foot controller setup, or quick disconnects. This development allows as many
hand pieces and rotaries as needed to be operated at the same time. The basic principle of the controller for the tool
is also patented.
3. One way to move the length-of-stroke adjustment to the outside of the hand
piece was the ring pictured above. Only one of these was made as a prototype and
it was patented when the snap on/off handle was patented. The tool worked nicely,
but it was difficult to make and assemble because of all the small internal
4. In the design shown above, stroke adjustment was still in the tool hole, but
the addition of the black rings around the body made it possible to adjust the
exhaust by turning the ring. When a stroke adjustment was made, the exhaust
could also be tuned to make them run even better.
The stroke adjustment on the tools makes one hand piece as versatile as a
variety of different-sized hand pieces.
5. Away to adjust the stroke by moving the nose in and out with a
ring around the body, while simultaneously adjusting (tuning) the exhaust was an
Synchronizing the two made the tool run well throughout the stroke range,
without having to adjust one and then the other. The ring works in a manner
similar to focusing a lens on a camera. Because of the way the nose is held in
place, the impacts are isolated to the nose and graver shank. This leads to less
vibration to the body during impacting, and provides significantly more power
The stroke adjustment is similar to gears in a car and makes the tool perform like numerous handpieces in
one. First gear is good for shading and fifth gear is good for background. If thinking about it this way, the past blow-pulse machines similar to my father's machine has
6. The development of the PalmControl meant the
elimination of the foot pedal. I noticed that while engraving with a foot pedal,
engravers also vary the pressure used to hold the graver point in a cut.
Depending on the depth, engravers vary the amount of palm pressure. This idea
was built upon by making a handle that would automatically respond to the palm
pressure to operate the throttle. The concept for the PalmControl was: why do we
have to duplicate with a foot pedal what our hand is already doing? It was also patented. The legal enforceable claims of the patent protect a hand push pressure activated power tool used in the
hand engraving and jewelry fields.
Note: Comments were made by an owner of a competitor that the Lindsay
PalmControl is nothing new. However, the PalmControl technology had not been described or illustrated in a dated public magazine
prior. A publication such as this is termed
proof of valid prior art. The patent issued only after thorough examination by the United States Patent Office, which courts consider the foremost experts in determining
novelty, obviousness, etc. If the engraving world had known of the abilities of this engraving technology, have no doubt that it would have been exploited long ago by a
For further reading Michael Arternis has written an
informative article titled insight into the patent system
The PalmControl patent protects a hand push pressure activated power tool used in the hand engraving and jewelry
fields as described in one of the legal claims of patent that is provided below. Infringement of the claims of this patent or any of the Lindsay patents by competitor
tool manufactures will be
"A hand-held power tool for use in hand working operations in the hand engraving and jewelry fields, comprising: a body having first and second ends; a tool tip holder
located at said first end for holding a tool tip; a handle made to be held in the human hand on said body; a variable power means for delivering variable power to said
tool tip; a pressure sensing means for sensing the amount of pressure exerted by a human hand between said handle and said tool tip; said variable power means will
increase in power when said pressure sensing means senses increased pressure exerted by the user of said hand-held power tool on said handle with the human hand; and
said variable power means will decrease in power when said pressure sensing means senses decreased pressure exerted by the user of said hand-held power tool on said
handle with the human hand."