Shop Vac Air Lift Platform
The Dougster
850 pounds or so. The rated weight is 480 pounds at:
http://www.smithy.com/uploads/SuperShop%20PDF%20Brochure.pdf
where we read "WE SQUEEZED A 500 SQ. FT. WOOD SHOP INTO JUST 12 SQUARE
FEET!"
480 pounds / 12 sq ft = 40 psf
40 psf / 144 = ~ 0.2 psi
I think my Shop Vac 222-75, an ancient metal can "The Brute", can do
that; it pulls 600 watts and uses 2-1/2 inch hose. The perimeter is
going to be about 192 inches, and that hose area is less than 8 sq in,
so I figure the gap has to be less than 8/192 in or about 40 mils. Our
floor is that flat; the Korean craftsmen worked hard scraping it by
hand with two coats of grout.
I guess I'll give it a try. I have an 80 x 36 inch door and some old
bicycle inner tubes. We'll see how it goes.
First, though the Shop Vac needs a roller skate bearing. You can
imaging how delighted I was when I looked inside and saw that the
Singer Company Motor Division chose a 608 bearing for the impeller.
You can get those anywhere. Schmoopie's getting one in all stainless
steel, ABEC-3, at Grainger tomorrow. I figured 3 was fine; both the
class 3 and the available class 5 bearing are rated to 35,000 rpm and
I just got an old variac from my trip to Boston for barn-cleaning.
Cold outside....
Warmly,
Douglas (Dana) Goncz, CPS
Replikon Research
Seven Corners, VA 22044-0394
RoyJ
Not sure what the pressure side is, should be a bit more. With that kind
of pressure your door should lift 2880 pounds. The ratio of the hose to
the perimeter is pretty much immaterial as long as it can maintain the
required pressure.
Bill Noble
hovercraft - there are plans for ones with a leaf blower
"RoyJ" <spam...@microsoft.net> wrote in message
news:AqGdnX_5F6TNRoDW...@earthlink.com...
The Dougster
wrote:
(snip calculations)
> First, though the Shop Vac needs a roller skate bearing. You can
> imaging how delighted I was when I looked inside and saw that the
> Singer Company Motor Division chose a 608 bearing for the impeller.
> You can get those anywhere. Schmoopie's getting one in all stainless
> steel, ABEC-3, at Grainger tomorrow. I figured 3 was fine; both the
> class 3 and the available class 5 bearing are rated to 35,000 rpm and
> I just got an old variac from my trip to Boston for barn-cleaning.
Damn. The new bearing didn't change a thing. I though the loose,
rusted bearing (from sucking in too much water *once*) let the
commutator wobble, causing the sparking I see with loss of power. Hm.
I slotted, filed, and finished the commutator. I did a spetacular job
filing, finishing with a Revlon nail file. Very smooth.
My Crazy-Glue and baking soda commutator filler bars didn't last.
Crazy Glue is cyanoacrylate self-polymerizing liquid.
I think I need a better filler. I have acrylic powder microballons and
acrylic monomer. I think I could fill the gaps with powder first and
then add monomer to all of them, but the powder falls out of the
lowest gap that way. Maybe I could do it on the lathe...
Filling each gap with powder and adding monomer to only that gap is so
damn hard. My hands shake. They gave me a needle applicator.
Acrylic-acrylic is better than baking soda - acrylic.
It's fun trying different repairs. I have other vacuum cleaners.
What did they use in the old days? Phenolic? I have some Glyptal
spray, the high-solids motor varnish, a hazmat from MSC. Masked and
sprayed into the gaps, baked properly, then turned away leaving the
filled gaps, that might be best of all that I have available.
Doug
Bill Noble
snip
>
> What did they use in the old days? Phenolic? I have some Glyptal
> spray, the high-solids motor varnish, a hazmat from MSC. Masked and
> sprayed into the gaps, baked properly, then turned away leaving the
> filled gaps, that might be best of all that I have available.
>
> Doug
the separator between commutator segments is usually mica, it has to handle
temperature. the segments are undercut a little.
If you are getting significant arcing and loss of power, you have at least
one shorted armature segment - you can verify this with a growler.
The Dougster
A shorted rotor segment? Oh. I remember the shop manual for my Jeep
DJ-5A showed how to use a growler for the alternator. The rural
posties had to maintain their vehicles.
A 60 Hz AC field induces current in the shorted segment only, is that
right? You feel for the induced field with a thickness gage blade, or
even a hacksaw blade. It "growls" when you're on the segment.
That's how it works, the way I remember it. I have such a coil, it's a
poor man's "ultrasonic" cleaner; it agitates a roller skate bearing at
60 Hz in a little steel cup.
But you wrote "armature". That's the outer coil. At least I thought it
was. Hm.
Tell me more, please, Bill; this is interesting.
Doug
Winston
> But you wrote "armature". That's the outer coil. At least I thought it
> was. Hm.
Nuh uh. The outer coil is the stator.
The rotor is the armature.
http://www.sawmillcreek.org/articles/5/motor1.jpg
I pick up my experimental shop vacs cheap on Craig's List.
It is *way* faster than repairing.
--Winston
--
Congratulations Robert Piccinini and Steven A. Burd, WalMart Publicists of the Year!
Bill Noble
"The Dougster" <dgoncz.70...@gmail.com> wrote in message
news:1dfdc8e2-b923-423a...@g26g2000yqe.googlegroups.com...
armature is the coil that moves, stator is the coil that does not move.
High probability that you have a bad armature
yes, you remember growler correctly
Lloyd E. Sponenburgh
news:hfsjj...@news2.newsguy.com:
> Nuh uh. The outer coil is the stator.
> The rotor is the armature.
I'm not looking at _that_ motor, so I'm not arguing about that one, but you
realize that there are "rotating stator" designs, also; right?
LLoyd
Winston
I'm not aware of any.
I do see 5 hits on the phrase "rotating stator motor" in Google, but three
of those are duplicates that do not translate from Italian, one is a patent
for a novel design and one hit is not actually in the cited text.
Nine of ten Google definitions for "stator" refer to it as the
fixed, non-rotating part of the motor. (The tenth definition concerns
a part for a door lock, not for a motor.)
Contrast that to 127,000 hits for the phrase "rotating field winding" as
in an alternator, for example. I agree that it's field is produced by a
spinning rotor or armature, not it's stator (as it is in a 'squirrel cage
motor').
"Rotating Stator" appears to be one of those potentially useful concepts
that never actually existed. See also:
"Civil Rights"
"Management Ethics"
"Budget Surplus" ...&c
Wild_Bill
within the field coils (field assemly).
In universal motors, the field assembly isn't usually referred to as a
stator (in the USA, for as long as I can remember).
Stator is a term frequently used with induction motors.
A weird little motor I saw years ago in an old dictation machine (voice
recorder), where the DC motor housing was used as the drive platen for the
band of recording media.
In that motor, the wound armature was stationary, and the case rotated
around it.
--
WB
.........
metalworking projects
www.kwagmire.com/metal_proj.html
"Winston" <Win...@bigbrother.net> wrote in message
news:hfsjj...@news2.newsguy.com...
Winston
> Motors in vacs are generally universal motors, and the armature rotates
> within the field coils (field assemly).
> In universal motors, the field assembly isn't usually referred to as a
> stator (in the USA, for as long as I can remember).
Shore it is, officially and colloquially.
Ohio, USA: http://www.globe-usa.com/micafil.htm
California, USA: http://america.renesas.com/fmwk.jsp?cnt=motor_types_child.htm&fp=/applications/motor_control/child_folder/&title=Motor%20Types
Arizona, USA http://ww1.microchip.com/downloads/en/AppNotes/00905a.pdf
> Stator is a term frequently used with induction motors.
Yup.
> A weird little motor I saw years ago in an old dictation machine (voice
> recorder), where the DC motor housing was used as the drive platen for
> the band of recording media.
> In that motor, the wound armature was stationary, and the case rotated
> around it.
An external rotor 'pancake motor' as used in brushless fans, for example?
http://www.allaboutcircuits.com/vol_2/chpt_13/6.html
The part that holds the windings is still the 'stator' because it is fixed
to the assembly. The 'outside rotor' is the type you refer to, yes?
Wild_Bill
called out as a stator in any parts lists.
The use of the term stator that I'm used to seeing, has been associated with
induction motors or automotive alternators.
I'm fairly certain that the weird platen motor in the dictation machine was
a permanent magnet type DC. It was a portable model, probably made in the
60s.
--
WB
.........
metalworking projects
www.kwagmire.com/metal_proj.html
"Winston" <Win...@bigbrother.net> wrote in message
news:hfu1i...@news7.newsguy.com...
Joseph Gwinn
Winston <Win...@bigbrother.net> wrote:
> Lloyd E. Sponenburgh wrote:
> > Winston <Win...@bigbrother.net> fired this volley in
> > news:hfsjj...@news2.newsguy.com:
> >
> >> Nuh uh. The outer coil is the stator.
> >> The rotor is the armature.
> >
> > I'm not looking at _that_ motor, so I'm not arguing about that one, but you
> > realize that there are "rotating stator" designs, also; right?
>
> I'm not aware of any.
>
> I do see 5 hits on the phrase "rotating stator motor" in Google, but three
> of those are duplicates that do not translate from Italian, one is a patent
> for a novel design and one hit is not actually in the cited text.
>
> Nine of ten Google definitions for "stator" refer to it as the
> fixed, non-rotating part of the motor. (The tenth definition concerns
> a part for a door lock, not for a motor.)
>
> Contrast that to 127,000 hits for the phrase "rotating field winding" as
> in an alternator, for example. I agree that it's field is produced by a
> spinning rotor or armature, not it's stator (as it is in a 'squirrel cage
> motor').
>
> "Rotating Stator" appears to be one of those potentially useful concepts
> that never actually existed. See also: ...
This is an induction motor where the rotor bars are in a iron cage that
surrounds the stationary cylindrical stator. The inside-out induction
motor design is very common in disk drives, and was used in some
high-end vinyl-record turntables. The advantages are that the flywheel
and motor are combined, saving space, parts count, and (if production
volume was sufficient) money.
Such motors were never a catalog item, instead being an integral part of
something else, so a google search for the motor type won't much help.
Joe Gwinn
Winston
(...)
> Such motors were never a catalog item, instead being an integral part of
> something else, so a google search for the motor type won't much help.
Au contrare, Joe.
You describe the classical and ubiquitous 'external rotor' motor.
(52,000 Google hits on the phrase '"external rotor" motor' just now)
mcmaster.com shows many examples as 'equipment cooling fans' on page 626:
http://www.mcmaster.com/#electronic-equipment-cooling-fans/=4w1exy
The stator lives inside the rotor as you say. It remains fixed whilst
the external rotor spins around it.
We can violently agree on that. :)
I'm not talking about 'Rotating Stator' motors, because they don't exist
unless your reference frame is spinning in the opposite direction.
Stators spin only when you've lost your tail rotor.
That is operating them far outside their specifications
and is not recommended. :)
Joseph Gwinn
Winston <Win...@bigbrother.net> wrote:
> Joseph Gwinn wrote:
>
> (...)
>
> > Such motors were never a catalog item, instead being an integral part of
> > something else, so a google search for the motor type won't much help.
>
> Au contrare, Joe.
>
> You describe the classical and ubiquitous 'external rotor' motor.
> (52,000 Google hits on the phrase '"external rotor" motor' just now)
Did you check which of the 52,000 hits were technical descriptions
versus catalog offerings of motors not built into something else?
(There! That'll keep him busy for 100 years.)
> mcmaster.com shows many examples as 'equipment cooling fans' on page 626:
> http://www.mcmaster.com/#electronic-equipment-cooling-fans/=4w1exy
Cooling fans - yes I forgot to list them, and they are by far the
largest volume example.
> The stator lives inside the rotor as you say. It remains fixed whilst
> the external rotor spins around it.
>
> We can violently agree on that. :)
>
> I'm not talking about 'Rotating Stator' motors, because they don't exist
> unless your reference frame is spinning in the opposite direction.
We may have gotten into a semantic tarpit, but I do recall seeing such
motors in old books on electric motor design, recounting the days when
every variation was tried, the winners being the stat=ndard designs of
today.
> Stators spin only when you've lost your tail rotor.
>
> That is operating them far outside their specifications
> and is not recommended. :)
Autogyro operation is in the specs, is it not?
Joe Gwinn
Winston
(...)
> Did you check which of the 52,000 hits were technical descriptions
> versus catalog offerings of motors not built into something else?
> (There! That'll keep him busy for 100 years.)
Heh! (Too) many of them were ads from Chinese manufacturing plants.
That fact saddened me so I didn't pursue it further.
(...)
> We may have gotten into a semantic tarpit, but I do recall seeing such
> motors in old books on electric motor design, recounting the days when
> every variation was tried, the winners being the stat=ndard designs of
> today.
Each has it's strong points. The hub motor on my bicycle is of
the 'external rotor' type. Makes a compact, powerful package, it does.
>> Stators spin only when you've lost your tail rotor.
>>
>> That is operating them far outside their specifications
>> and is not recommended. :)
>
> Autogyro operation is in the specs, is it not?
Always!
Joseph Gwinn
Winston <Win...@bigbrother.net> wrote:
> Joseph Gwinn wrote:
>
> (...)
>
> > Did you check which of the 52,000 hits were technical descriptions
> > versus catalog offerings of motors not built into something else?
> > (There! That'll keep him busy for 100 years.)
>
> Heh! (Too) many of them were ads from Chinese manufacturing plants.
> That fact saddened me so I didn't pursue it further.
But there is just one immense electric noodle plant that makes them all.
> (...)
>
> > We may have gotten into a semantic tarpit, but I do recall seeing such
> > motors in old books on electric motor design, recounting the days when
> > every variation was tried, the winners being the stat=ndard designs of
> > today.
>
> Each has it's strong points. The hub motor on my bicycle is of
> the 'external rotor' type. Makes a compact, powerful package, it does.
Also far easier to seal against dirt.
> >> Stators spin only when you've lost your tail rotor.
> >>
> >> That is operating them far outside their specifications
> >> and is not recommended. :)
> >
> > Autogyro operation is in the specs, is it not?
>
> Always!
Good to know - the ground is soo far away.
Joe Gwinn
Winston
(...)
> But there is just one immense electric noodle plant that makes them all.
That's the way it looks from here, anyway.
I suspect the country is large enough to support more than one plant.
(Don't quote me on that.)
(...)
>>> Autogyro operation is in the specs, is it not?
>> Always!
>
> Good to know - the ground is soo far away.
I understand that a helicopter 'engine out' recovery is one of those
life - changing occurrences one hopes never to experience.
I can well do without it, ThankYouVeryMuch!
--Winston
Lloyd E. Sponenburgh
> I understand that a helicopter 'engine out' recovery is one of those
> life - changing occurrences one hopes never to experience.
> I can well do without it, ThankYouVeryMuch!
>
You must be a civilian "rider". Military rotary-wing pilots practice
auto-rotation landings almost constantly.
While I was an outpatient at Cam Rahn Bay airbase after a minor wound, I
watched (actually) hundreds of "dead-stick" landings of UH-1s on PSP
runways a week.
As a pilot myself, I get a little tickled by the civilian perception that
when you crash, you die. A military is pilot is taught, "when you crash,
this is what you do next...".
LLoyd
Winston
> Winston <Win...@bigbrother.net> fired this volley in
> news:hg189...@news6.newsguy.com:
>
>> I understand that a helicopter 'engine out' recovery is one of those
>> life - changing occurrences one hopes never to experience.
>> I can well do without it, ThankYouVeryMuch!
>>
>
> You must be a civilian "rider".
Yup. Totally. The classical 'zero timer'.
> Military rotary-wing pilots practice
> auto-rotation landings almost constantly.
That is a reasonable thing to do.
Still, takes 'Balls of Titanium'.
Watching the ground come up that quickly has to be upsetting. :)
> While I was an outpatient at Cam Rahn Bay airbase after a minor wound, I
> watched (actually) hundreds of "dead-stick" landings of UH-1s on PSP
> runways a week.
>
> As a pilot myself, I get a little tickled by the civilian perception that
> when you crash, you die. A military is pilot is taught, "when you crash,
> this is what you do next...".
Good things to know, no doubt.
I'm still trying to comprehend the '11 different kinds of altitude'.
--Winston
--
DoN. Nichols
> In article <hftni...@news5.newsguy.com>,
> Winston <Win...@bigbrother.net> wrote:
>
>> Lloyd E. Sponenburgh wrote:
>> > Winston <Win...@bigbrother.net> fired this volley in
>> > news:hfsjj...@news2.newsguy.com:
>> >
>> >> Nuh uh. The outer coil is the stator.
>> >> The rotor is the armature.
>> >
>> > I'm not looking at _that_ motor, so I'm not arguing about that one, but you
>> > realize that there are "rotating stator" designs, also; right?
>>
>> I'm not aware of any.
>>
>> I do see 5 hits on the phrase "rotating stator motor" in Google, but three
>> of those are duplicates that do not translate from Italian, one is a patent
>> for a novel design and one hit is not actually in the cited text.
[ ... ]
>> "Rotating Stator" appears to be one of those potentially useful concepts
>> that never actually existed. See also: ...
>
> This is an induction motor where the rotor bars are in a iron cage that
> surrounds the stationary cylindrical stator.
I know these as "inverted rotor" motors.
> The inside-out induction
> motor design is very common in disk drives, and was used in some
> high-end vinyl-record turntables.
And -- interestingly enough -- they were used in the old Hunter
ceiling fans. I'm not sure about the current ones, with the manufacture
outsourced to China.
I've also seen one in a mil surplus 10.5" tape deck. It had
windings for three speeds, not the usual two. Then it burnt out, and I
had the fun of trying to learn enough to rewind it so it would work
again. I did manage -- sort of. I think that I had less torque than it
originally had. But the bearings were rather old by then, and I d id
not (at that time) have the equipment needed to either make a new set of
sintered bronze bearings nor to re-design it to run on ball bearings.
FWIW -- it was a cap-run motor, not a cap start one.
> The advantages are that the flywheel
> and motor are combined, saving space, parts count, and (if production
> volume was sufficient) money.
Indeed so.
> Such motors were never a catalog item, instead being an integral part of
> something else, so a google search for the motor type won't much help.
Amen!
Enjoy,
DoN.
--
Email: <dnic...@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---
Winston
> On 2009-12-11, Joseph Gwinn <joeg...@comcast.net> wrote:
(...)
>> Such motors were never a catalog item, instead being an integral part of
>> something else, so a google search for the motor type won't much help.
>
> Amen!
>
> Enjoy,
> DoN.
Hey Joe and DoN, Can you call these folks Monday and tell them to
remove all 147 of these external rotor motor types from their catalog?
http://www.ziehl-abegg.com/us/download-589.html
Also these guys need to know that their six products cannot be found:
http://www.nesail.com/detail.php?productID=2613
There are only two types available from these guys, but still
they need to know that they are invisible...
http://www.zyec.com/en/product3.asp?cc=59#
There are duplicates but the companies that provided these 38
listings need to know that they cannot be seen:
http://www.alibaba.com/showroom/External_Rotor_Motor/--1404------------------------.html?noddp=Y
Thanks! :P
Larry Jaques
<Win...@bigbrother.net> scrawled the following:
Thanks, Winnie. And for those of you who wish to find those invisible
listings, too, use my new, FREE Invisible Search Engine located here:
Enjoy!
--
Don't forget the 7 P's:
Proper Prior Planning Prevents Piss-Poor Performance
Joseph Gwinn
Winston <Win...@bigbrother.net> wrote:
> DoN. Nichols wrote:
> > On 2009-12-11, Joseph Gwinn <joeg...@comcast.net> wrote:
>
> (...)
>
> >> Such motors were never a catalog item, instead being an integral part of
> >> something else, so a google search for the motor type won't much help.
> >
> > Amen!
> >
> > Enjoy,
> > DoN.
>
>
> Hey Joe and DoN, Can you call these folks Monday and tell them to
> remove all 147 of these external rotor motor types from their catalog?
> http://www.ziehl-abegg.com/us/download-589.html
>
> Also these guys need to know that their six products cannot be found:
> http://www.nesail.com/detail.php?productID=2613
>
> There are only two types available from these guys, but still
> they need to know that they are invisible...
> http://www.zyec.com/en/product3.asp?cc=59#
>
> There are duplicates but the companies that provided these 38
> listings need to know that they cannot be seen:
> http://www.alibaba.com/showroom/External_Rotor_Motor/--1404-------------------
> -----.html?noddp=Y
Uncle. Even if not all came from the electric noodle factory.
Joe Gwinn
Winston
(...)
> Uncle. Even if not all came from the electric noodle factory.
Well, the last 38 listings look pretty noodly to me.
:)
--Winston <-- Our token Pastafarian
The Dougster
> Motors in vacs are generally universal motors, and the armature rotates
> within the field coils (field assemly).
> In universal motors, the field assembly isn't usually referred to as a
> stator (in the USA, for as long as I can remember).
> Stator is a term frequently used with induction motors.
>
> A weird little motor I saw years ago in an old dictation machine (voice
> recorder), where the DC motor housing was used as the drive platen for the
> band of recording media.
> In that motor, the wound armature was stationary, and the case rotated
> around it.
I'm building two just like that for a tube mitering machine!
Burden's Surplus Center has two dual shaft motors with suitable 5/16
shafts, one AC and one DC, and a cheap fan blade to fit. I plan to
build a case "back around" each motor in two halves which rotate
together, with a fan blade in each, and a stout bracket 'round the
center to hold it it. Then, a sanding belt will go over that, and the
other end will be various sized drums (1, 1-1/8, 1-1/4, ... 2) of
aluminum or steel tubing held by those neat little 2 inch 3-jaw chuck
sold at Harbor Freight. A couple of v-blocks later, I'll be happily
mitering tubes from 1-2 inches for just about anything.
I originally wrote "tuber mitering machine" but who would miter...a
potato? :)
Doug
The Dougster
> Joseph Gwinn wrote:
>
> (...)
>
> > Did you check which of the 52,000 hits were technical descriptions
> > versus catalog offerings of motors not built into something else?
> > (There! That'll keep him busy for 100 years.)
>
> Heh! (Too) many of them were ads from Chinese manufacturing plants.
Winston and Joseph have pointed to "search engine flooding", a
practice used by "eyeball vendors" to make damn sure somebody clicks
on one of your (many...too many) pages, each a duplicate of the other
with some minor variation. Pre-searched pages for all the popular
search terms.
I hate 'em. Yuck.
Marshall McLuhan, was it?
"You are the product. The media company sells you to the advertiser.
The advertiser buys you and does whatever they want to with you." or
something *not entirely unlike* that.
Doug
The Dougster
> >news:hg189...@news6.newsguy.com:
>
> >> I understand that a helicopter 'engine out' recovery is one of those
> >> life - changing occurrences one hopes never to experience.
> >> I can well do without it, ThankYouVeryMuch!
>
> > You must be a civilian "rider".
>
> Yup. Totally. The classical 'zero timer'.
>
> > Military rotary-wing pilots practice
> > auto-rotation landings almost constantly.
>
> That is a reasonable thing to do.
> Still, takes 'Balls of Titanium'.
> Watching the ground come up that quickly has to be upsetting. :)
The old arcade video game "Lunar Lander" did this. Best strategy was
hold off firing the rocket until you'd fallen and it looked like it
was a crash. There was a fuel gage, if I remember right. It was a
great game, that one and Space Invaders, where you had to fire along
the flanks to reduce the "step-forward" time by making the column
thinner while the margins stayed the same.
Rotating stator. What would Einsein have said? Not an inertial
reference frame, probably. Hawkings, though...he'd have something to
say about it.
I read up before the OP and found the procedure for trimming
quadrature to the applied field, but also to that field distorted by
the rotor's presence *and* switched field. And I see none of that
trimmability in my motor; it's running 50% or less of how it should.
I'll keep at it.
Doug
Doug
DoN. Nichols
> DoN. Nichols wrote:
>> On 2009-12-11, Joseph Gwinn <joeg...@comcast.net> wrote:
>
> (...)
>
>>> Such motors were never a catalog item, instead being an integral part of
>>> something else, so a google search for the motor type won't much help.
>>
>> Amen!
>>
>> Enjoy,
>> DoN.
>
>
> Hey Joe and DoN, Can you call these folks Monday and tell them to
> remove all 147 of these external rotor motor types from their catalog?
> http://www.ziehl-abegg.com/us/download-589.html
My complaint was about the "rotating stator" term, which is a
built-in contradiction.
"External rotor" is a reasonable enough variation on "inverted
rotor" so I would be willing to use these terms interchangably.
I won't bother downloading the others, on the assumption that
they also deal with "External rotor", not "rotating stator". :-)
BTW I've also seen a similar design used for the 400 Hz 3-phase
motors used in old interial navigation instruments for aircraft.
I had no manuals for the ones which I had, so I don't know what
the *official* term was used for them.
Winston
> On Dec 12, 7:46 pm, Winston <Wins...@bigbrother.net> wrote:
(...)
>> Watching the ground come up that quickly has to be upsetting. :)
>
> The old arcade video game "Lunar Lander" did this.
Not for me, even in geologically active California.
I didn't suffer so much as a scratch when crashing the Lander.
> Rotating stator. What would Einsein have said? Not an inertial
> reference frame, probably.
Shore! It's a classical example. If you witness a 400 ton boulder
spinning at 1000 RPM clockwise, first make sure that your inertial
reference frame *isn't* spinning at 1000 RPM counterclockwise.
> Hawkings, though...he'd have something to
> say about it.
It's all relative. (Rimshot)
(...)
> I'll keep at it.
Excellent.
Winston
> On 2009-12-13, Winston <Win...@bigbrother.net> wrote:
>> DoN. Nichols wrote:
>>> On 2009-12-11, Joseph Gwinn <joeg...@comcast.net> wrote:
>> (...)
>>
>>>> Such motors were never a catalog item, instead being an integral part of
>>>> something else, so a google search for the motor type won't much help.
>>> Amen!
>>>
>>> Enjoy,
>>> DoN.
>>
>> Hey Joe and DoN, Can you call these folks Monday and tell them to
>> remove all 147 of these external rotor motor types from their catalog?
>> http://www.ziehl-abegg.com/us/download-589.html
>
> My complaint was about the "rotating stator" term, which is a
> built-in contradiction.
That was my first concern.
The Dougster
wrote:
> On Dec 7, 8:54 pm, I, The Dougster <dgoncz.703.475.7...@gmail.com>
> wrote:
> (snip calculations)
>
> > First, though the Shop Vac needs a roller skate bearing.
(snip)
> Damn. The new bearing didn't change a thing. I though the loose,
> rusted bearing (from sucking in too much water *once*) let the
> commutator wobble, causing the sparking I see with loss of power. Hm.
> I slotted, filed, and finished the commutator. I did a spetacular job
> filing, finishing with a Revlon nail file. Very smooth.
(snip)
> What did they use in the old days? Phenolic? I have some Glyptal
> spray, the high-solids motor varnish, a hazmat from MSC. Masked and
> sprayed into the gaps, baked properly, then turned away leaving the
> filled gaps, that might be best of all that I have available.
I tried the Glyptal-like spray, first a wet coat onto a masked
commutator (from a jigsaw motor) rotating in the lathe to resist runs,
and a hair dryer to set it, and baked at about 150 deg F, then a
lighter coat for pinholes, baked. It seems to work and files down
nicely. I am probably smearing copper in between bars, so a bit of
undercutting will be needed. I think this is the way to go with the
Shop Vac motor.
Uh-oh. I forget to vent the nozzle after spraying. To Do List... just
remembered it now.
Use it up, wear it out, make it do, or do without. That kind of
thinking.
Doug