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Pendant motor alternatives


#1
Actually, I barely use either one of my flexshaft motors anymore,
........ since I went to a Lindsay Airgraver and a high-speed
handpiece.

Every now and then on this forum, someone indicates they no longer
use hanging motors. Would you all discuss the differences between two
alternatives that are sometimes mentioned, micromotors and the
Airgraver?

Is the reason you have an Airgraver specifically for power assisted
gravers, and you use it for other tasks because you have it?

Not including gravers, which tasks do you perform with a micro-motor
and which tasks with the Airgraver? Is your decision-making based on
handpiece, power and speed or the flexibility of the one flexshaft
alternative that can do everything?

In the archives, David talks about a number of tasks he performs
with the Airgraver. He mentions the use of the air compressor by way
of using the Airgraver manifold. I do not understand.

Excluding power assisted gravers, would you buy an Airgraver for
carving, hammering, and what else could you do with the Airgraver
that you would not do with a micro-motor?


#2

Hi Betty, great questions! The main operational difference between a
flex shaft motor and a micromotor (high-speed handpiece) is that the
micromotor runs far more true. They are also much more quiet than a
flexshaft. If you have ever used a Dremel tool, you are familiar
with the sound and feel of a micromotor. There is no wobble like that
caused by the flexible shaft slapping around in it’s sheath that you
find with a flex shaft, so burs run true. They impart no vibration
whatsoever to the bur, rubber wheel or whatever tool is chucked up.
Another major benefit with most micromotors is that you can select to
operate it with a foot pedal or just set a specific speed from 100
RPM to 40,000. Many also offer different speed ranges for the foot
pedal to operate within. For instance, I can set mine to run between
0 and a maximum of 1000 RPM, so when I floor it, it’s only turning
1000 rpm. Or I can set it to a max of 40,000 RPM so at half-pedal
it’s at roughly 20,000 RPM, or any maximum I want between the two.
The good ones also equalize the torque applied across the speed
range, so even when running at 150 RPM, it has just as much torque as
it does at 10,000. Many also offer the option of running in reverse,
which can be a pretty handy feature especially for finishing
operations.

The primary downside to micromotors is that they are commonly
equipped with a collet that limits their use to burs or other tools
with a 1/8th inch or 3/32 inch shank and it’s not a quick change. The
solution is to have two separate handpieces, each with a different
collet. Many micromotor controllers are set up to run two or more
handpieces. Being as the handpiece is equipped with a collet instead
of a chuck, it can’t be used with any of the different types of tools
that a flexshaft can be used for, for instance some of the wax tools
and other tools that use fixtures to keep burs and things aligned
with the work. They also can’t operate a Badeco style hammer. The
other major downside is the cost. A good one can cost much more that
a flexshaft. This is rapidly changing though; it’s no longer
necessary to spend $1000 or more. The Foredom tool is closer to $400.
It is kind of bare-bones compared to some of the higher end tools,
but it works well.

I only use my flexshaft when I need to chuck up a tool with a shank
size other than 3/32" such as drill bits or large burs. It really
does feel like an old truck after using my highspeed handpiece. Using
a 003 ball bur to carve extremely fine detail in wax or metal is not
really possible with a flexshaft, they wobble way too much to allow
any real precision at those dimensions, but it’s a pure joy with a
micromotor.

The reason I have a Lindsay Airgraver is primarily for engraving.
The GRS Gravermach is similar, and although it is engineered
differently and isn’t quite as precise as the Lindsay (imho, I have
both), for the sake of this discussion, they are all but
interchangeable. Some purists will argue that using any power tool
for engraving precludes using the term “hand engraved” and I won’t
get into that argument here, but that’s what I do with it. I also use
it for every task that I used to use my Badeco hammer handpiece for
and many more.

If engraving isn’t part of the job description, its primary
advantage over the Badeco is that it can hold many different tools,
whereas the Badeco and similar hammers must use a threaded anvil
exclusively. The anvils can be ground into any shape, but they only
come in one size and hardness. They aren’t available in 1/8 "square
carbide for instance.

The main job most people use a Badeco for is hammering down bezels
and channel walls. They do a great job at that, but that’s about all
they’re good at. An air powered hammer on the other hand is much
more versatile and is especially well suited for other tasks like
bead setting and pave’ that require several different types of tools
like round, flat and onglette gravers, milgraine tools and beading
tools. It is much easier on the hand when raising lots of beads than
using a manual handle but can round a bead with a tiny number 2
beading tool with the same extreme precision. An air powered hammer
also doesn’t impart the rotational vibration that a flexshaft driven
tool intrinsically does regardless of how firmly it is held.

The only downside to an air powered hammer is the cost. By the time
you add a compressor, they can be very expensive. The cost probably
isn’t justifiable if everything it is to be used for can be
accomplished with a flexshaft powered hammer.

I would have written a shorter response, but I didn’t have the
time…

Hope this is what you were looking for, Betty.
Dave Phelps


#3

Micro-Motors!!!

Ive been using micro-motors for the past…10+ YEARS!! I only use
these basically for Diamond Setting & travelling to visit clients.
The nice part is that there is freedom of movement while holding the
handle. Loads easy to move around.

How easy to travel. it packs in my suitcase with no problem. BTW, I
have two of them, one sits on my bench and another goes with me.
Gerry!

Gerry Lewy
gemsettingtutor.com


#4

Like Gerry, I have two micro-motors—one on my bench and one for
traveling. Also, as does Gerry, I use them for stone setting. They
are easier to use than my flexshafts, as I am not fighting the
shaft. I can get a good grip on the micro=rmotor hand piece, and I
like the fact that I have complete control of the speed using the
dial onthe micro-motor and not the foot pedal. Alma


#5

Betty,

Every now and then on this forum, someone indicates they no longer
use hanging motors. Would you all discuss the differences between
two alternatives that are sometimes mentioned, micromotors and the
Airgraver? 

First, the airgraver (or it’s competitors, such as the GRS engraving
systems) is not an alternative for a flex shaft motor in most cases.
It’s an engraving handpiece used with engraving tools, gravers, etc.
It differs from ordinary inexpensive gravers in that it’s the handle
to hold the gravers, but incorporates an impact mechanism, a little
like a miniature air hammer or hammer handpiece, used to help push a
graver through the metal without your hand having to actually push
the graver. Very handy if you do engraving, or stone setting work or
other tasks traditionally done with gravers. But the rotary tools
used in flex shaft handpieces/motors, are not used with the
airgraver.

Engravers often need to do very delicate removal of background
areas, and while this can be done the traditional way, with gravers,
especially flat ones, it’s often faster to do it with tiny rotary
tools. Because of the small size, these are often carbide, and work
best at high speeds. Micromotors are ideal for this.

There are also air driven handpieces, much like the very high
pitched whining sounding ones your dentist may use, that are even
more specific to this type of work.

Micromotors are somewhat similar in function to flex shafts, but
with a difference. Flex shaft motors work very well at quite low
speeds, and generally deliver a lot of torque. This makes them useful
where a degree of power is needed, driving larger burs or sanding
attachments, and more. They also work at high speeds, but most flex
shaft motors are limited to well under 20 thousand RPM. Thats fast,
but not really high speed. Micromotors, by contrast, generally can go
up to 35 thousand RPM or more, and at thise high speeds, bits and
cutters operate with noticably less drag, catching on the work less.
Some tools, like carbide cutters, really like being operated at these
speeds, as they chip less and cut better. But most micromotors (there
are exceptions) have substantially less power and torque, so larger
diameter tools don’t work quite as well. Also, the feel of the
micromotors is different in the hand, since you only have a light
coiled electric cord coming from the handpiece, instead of that
sometimes awkward flex shaft tied to the actual motor. With
micromotors, you also have pretty much just the one handpiece, though
some brands offer several types, including a hammer handpiece on the
badeco brand and a couple others. With flex shafts, the various
handpieces are generally interchangeable, and there are pages and
pages of different types in the catalogs. Finally, the cost.
Micromotors generally cost anywhere from around 400 to a couple
thousand, though there are a couple really basic and cheap lighter
duty Korean ones sold for around 150 to 200. (I have a couple of
these, and don’t regret them at all. Not high powered, limited to
only about 35K RPM, but they work reasonably well). On the other
hand, you can get cheap basic Flex shafts for a couple hundred
dollars. Adding quick change handpieces can quickly raise the cost of
your system, but they’re still much less expensive than the
micromotors. Generally, I’d expect the flex shaft machines to be
somewhat more durable too, in the degree to which they withstand
somewhat rough use and abuse.

Bottom line is that all three types of tool are distinct. The air
graver or GRS graver tools are distinctly difference, with different
uses. The flex shafts and micromotors overlap a lot. The big
difference is the micromotors are at home with more delicate but
higher precision uses at higher speeds, which the flex shafts are
slower, more powerful, with less precision (though that depends a
lot on the handpiece, more than anything else.)

If you’re just getting into jewelry, that flex shaft is almost one
of the beginner essentials. Almost. Not quite like basic hand tools,
but your capabilities will expand a lot once you have one.

If you’re exploring engraving, you can learn the old time way, with
manual push gravers. They work. But they can take a good bit of time
to master, and using them until you really are a master of the
things, will be a lot slower. The power gravers like airgraver will
cut your learning curve to a fraction of the time, so you spend your
time learning what the cuts look like, how to design, and that sort
of aesthetic aspects of engraving, rather than building up obscure
muscles in your hand, without which you’ll never quite control a
hand graver.

The micromotors aren’t essential to anything. But like any
semi-luxury tools, they’re really nice to use when they’re the right
tool, make some things work better or with more control, solve some
problems with the flex shafts, and make a great addition to the
workbench. Some specialists, especially diamond setters doing things
like micropave under a scope, (Or for that matter, dental techs
making crowns and bridges often using smaller precision abrasives,
diamond tools, etc,) may well use only their micromotors, while
others will use both.

That’s my two cents, anyway. Hope it helps.

Peter


#6

Hi Betty,

The various motors/powered graver units do different jobs.

The generic flex shaft/pendant drill unit is just that: generic. It
spins things, and has reasonable torque at low speed, and a
medium-ish top speed. Not a whole lot of fine speed control down
low, and the harder you lean into them, the more they bog down. But
they’re cheap, dependable, and plentiful. Most people start with one
of these, and if you had to pick just one, this would be the best
all-arounder.

There are high speed flex shaft units, or speed doubling handpieces
that get your speed up, at the cost of torque and fine speed
control. For some jobs, speed is life, so if you’re doing that sort
of thing, you want the fastest handpiece you can find.

Which need begat the micro motors. They have very good low end
speed control, combined with a blistering 30,000 RPM top end. (About
twice what the generic flex shafts will put out.) The reason for
that is that there’s only so fast you can spin the cable in it’s
jacket before the whole thing overheats and bad things happen. The
drawback, until recently, is that the good micromotors were about 5x
the price of a basic flex shaft. So yeah, they were (and are) great,
but they hurt to pay for. There are now Chinese knockoffs that are
half way decent, for roughly the same price as a flex shaft, so more
people are getting into them. (But the good ones still start at $1K,
and go way up from there.) Flex shafts? $250ish.

Another point in the flex-shaft’s favor is the interchangability of
the handpieces. The motor on the micro motors is built into the
handpiece, and that’s the pricey part, so you can’t swap them out
the way you can with a flex shaft.

So the micromotors are all collet machines, and can only grab things
that have the same size shank as whatever collet they have, which
limits the kinds of tooling you can run. A flex shaft with a #30
will grab anything. I’ve even spun bent nails, entire stone
settings, snips of tubing, and various other bits of improvisation
with them. Wouldn’t even think of doing that with a micromotor.
Besides, where are you going to find a #67 drillbit with a 3mm
shank? For less than $50 each? Right. Do that a couple of times, and
you’ve paid for a ‘spare’ flex shaft to keep around for the oddball
jobs, even if you do normally use a micromotor.

As far as the airgravers, they don’t do most of the things that the
flex shafts do. Flex shafts/micromotors spin their tools. Airgravers
pound. (there are teeny little air powered turbine handpieces that
do spin, and I have a memory that you can mount one on the
GraverMachs, but I also remember that they howl like a banshee.) So
for purposes of discussion, we’ll limit these to the reciprocating
hammer functions. For some parts of stone setting, it’s handy to
have a little ‘mini jackhammer’ to pound the bezel, seat, whatever
closed, but in a very gentle, and controllable way. Thus the hammer
handpieces for the flex shafts, or the airgravers. Airgravers,
especially the Lindsay ones, have a much more delicate ‘touch’ than
the reciprocating hammer handpieces. But you wouldn’t buy a $3-5K
system just for that. But if you already have it for engraving,
it’s entirely natural to use it instead of the hammer handpieces,
since it’s already right there and is a nicer tool. (The
GraverMach/airgraver are just the beginnings of the spend on that
kind of engraving system. There’s all sorts of support gear that’s
required to make effective use of them, which more than doubles the
cost of the setup. You’re looking at microscope, stand, sharpening
system, air compressor, etc. Many more thousands of dollars.) By
contrast, a Badeco hammer handpiece goes for about $275.

Make more sense now?

Regards,
Brian


#7

With all the experts weighing in, all I can do is discuss my
personal choices. Having used flex shafts in college, at Bowman, and
at the bench now, for over 40 years, they are my work horses, from
burring to setting to polishing, I use them enough that I find
myself replacing brushes inthe motor of at least one machine a year.
(Or at least it feels that often).Running a repair shop that must do
every phase, from simple repair to custom, I need machines that
serve a wide variety of purposes. I have 4 peddles beneath my bench.
1 runs the micro motor, which I use almost exclusively for heavier,
high speed grinding. Another runs the Grave Max, whichI use for any
graver, or hammering task. I also have 2 separate flex shafts
hanging on the bench. 1 runs my Technique handpiece set up with a
3/32 collet, and it is used for 90% of my work. The second flex
shaft is set up with a Foredom #30, Jacobs Chuck handpiece. This
unit holds anything not 3/32".It drills, holds inside emery
mandrels, Florentino burs, odd polishing tools (from Stuller pop
sticks, to cotton balls, and…), and this handpiece also fits into
the BenchMate holder system, and runs everything from Wolf carving
tools (spinning waxes, router table, drill press), to a Wolf belt
sander (with the handpiece removed), plus using the adaptor Kate
Wolf supplied, acts as a small bench lath.

I am sure some of my tools, such as the micro motor and the Grave
Max could be used for far better purposes than I currently employed
them for, but they all add in their own way to the productivity in a
repair type jewelry shop where every day I am faced with some unique
problem to solve, as quickly and efficiently as I can.


#8

Thank You for the detailed

Briefly, based on your answers, this is how the pendant motor,
micromotor and the Airgraver compare:

The micromotor has greater precision and control, but the flexshaft
will accept a wide variety of bit sizes and handpieces. Both are
rotary machines.

The hanging motor can produce a pulsing movement with a hammer
handpiece, although it is inferior to the Airgraver’s more delicate
and precise pulsing.

Due to cost, the only reason to buy an Airgraver is for using power
assisted gravers. It’s flexibility for performing other tasks is
incidental.


#9
The second flexshaft is set up with a Foredom #30, Jacobs Chuck
handpiece....... and this handpiece also fits into the BenchMate
holder system,.....

James, how do you attach the #30 handpiece to the Benchmate?


#10

James- “from Stuller pop sticks”

Ha! Me too. I wonder if Stuller knows that we use their dum dum
sticks as polishing tools? I eat the pops then chuck up and sharpen
the stick, add Tripoli or rouge and I can get into impossible little
places.

Have fun and make lots of jewelry.
Jo Haemer
timothywgreen.com


#11

Hi Betty,

Kate Wolf makes a little plastic widget that acts like a collet
letting you grab a #30 handpiece in the clamping ring that normally
grabs the ring clamp. About $10, and worth every penny. (Rio #
700897)

Ah, the joys of standardization.

Regards,
Brian


#12
The second flexshaft is set up with a Foredom #30, Jacobs Chuck
handpiece....... and this handpiece also fits into the BenchMate
holder system,..... 

James, how do you attach the #30 handpiece to the Benchmate? Brian
Meeks was spot on. This allows my to Chuck up blank round ring wax
bars, to turn for rings (Kate teaches how to turn all sorts of waxes
on this) I often use it to hold metal tubing that I am using to make
a series of bezel settings from (with diamonds you can cut the seat,
burnish the gemstone in place, saw off the complete, set bezel,
repeat)


#13

Well, Jo, what a nifty tip. I’ve used bamboo tooth picks with a wisp
of cotton wrapped around the tip, but love the idea of reusing
things. I will saythat the silicone naturally occurring in grasses
like bamboo, make the tooth picks abrasive by themselves. Now to
compare the lollipop stick to the bamboo tooth pick.

Judy in Kansas, where spring rains have stimulated all manner of
lovely flowering plants, not to mention nasty weeds too!


#14

Judy- Hmmm bamboo vs pop sticks. I see a future research paper for
the Santa Fe Symposium:-)


#15

Hi all:

On a tangentally related note…

I was reading a book written by the guy who restored/replaced the
Grinling Gibbons wood carvings at Windsor Castle, (the ones that
burned in the '88 fire.). They’re incredibly delicate and lifelike
wooden carvings, done in the ?1670’s?. There was much debate among
the museum people about how they were finished, as sandpaper didn’t
exist yet.

So this guy’s looking at them CAREFULLY, as you only really do when
you’re the poor bastard who’s been handed the job of doing it again,
and you can see your career flashing before your eyes. All he can see
is a bunch of parallel lines in groups of three, microscopically. No
idea what caused them, it certainly wasn’t sandpaper. So he
experiments with various period abrasives, and finally discovers a
reference to a particular type of swamp grass, akin to a cattail.
Turns out that (A) the leaves naturally concentrate silica from the
soil, and (B) they grow with three ribs down the center of the leaf.
At just exactly the spacing of the grooves on the surviving carvings.
So it turns out they were using naturally abrasive leaves for final
finishing. The Bamboo sticks are quite plausible as jewelry To bring
it back to jewelry, if you look at Theophilus, he talks about using
all sorts of sands and things for polishing silver, finishing up with
a final rub of ground charcoal in a rag. Turns out to work shockingly
well, does charcoal. For those of you who want to go "green’ (Black),
give it a try. Just wash your hands afterwards.

Regards,
Brian


#16

I do not see it as Bamboo vs Pop sticks. It is Bamboo, Pop sticks,
strings, toothpicks, worn out burs with a twist of cotton, anything
that will reach the area and carry the compoud you are trying to
Polish. My idea of an effective tool includes a wide selection of
options, tools and techniques.


#17

Q tips also work well

Vernon Wilson


#18

Brian- Talk about a blast from the past! Grinling Gibbons was a huge
influence in me as a baby goldsmith. I went to trade school in London
back in the 70s and once I learned about his work, wandering through
one or aThree Musketeers of that architectural artistic period in
England: Sir Christopher Wren, Capability Brown, and Grinling
Gibbons. Talk about three explosively inspirational artists. But of
the three no one set the bar for me as a carver as Gibbons.

Thanks for the reminder
Kate


#19

I just finished filming a set of videos for Lapidary Journal
(Interweave) onmy approach to and how I use my flex shaft, a tool
that is absolutely go-toin my studio.

Preparing for this project, I decided to buy a micro-motor along
with 2 handpieces, one brushless for general use and a hammer
handpiece. The difference in “run out” or how true a bit spins is
amazing. More accuracy, less “whip around” at the edges.

Other differences that I’ve so far noticed:

-The foot pedal is a different geometry than my tried & true Lucas:
I fumblea bit.

-the quick change collet system is not as easy to use as the lever
system onmy Foredom #20 or my older Techno X (now Technique). I’ve
seen this on my older micro motor as well.

-I have gotten used to the “coast down” aspect of a flex shaft: the
slowing down of the bit or bur as I take my foot off the pedal.

The MM doesn’t seem to work that way.

-The main handpiece is a little bigger and a different balance than
my #20 and Tecnique.

-The absence of a heavy cable/shaft actually takes some getting used
to! -Placement of the control unit took a little figuring out, since
I’m used tothe motor hanging above my bench.

I haven’t used the hammer HP too much yet, but it seems like it will
be great from what I’ve tried so far. Also tips/points are
interchangeable (I think) with my Foredom and Badeco hammers. I
definitely like the mobility that a micro motor gives the hammer HP.

I use my old adjustable #30 for so many things, spinning the work
against a stationary tool, so until I can find a chuck style
handpiece for this MM, I’ll keep my flex shaft where it is.

That’s it so far…

Andy


#20

Just another blast from the past. Many years ago the National Gallery
in Washington, D.C. had a show of British Stately homes. Can’t
remember the title offhand, but there were many objects including an
entire mantle carved by Grinling Gibbons. It was spectacular. It
seems to me that they used holly for at least some detailed carving -
I always wondered where they grew holly so large it could be used for
the larger pieces.

Thanks for the reminder.
Noralie