Dave,
I'm not sure that all of you guys on this list are aware of the fact
that the US has introduced metric units since a long time.
In 1866 Congress voted for the metric system, and in 1894 again
administration passed bills in that direction. Only in 1975, President
Gerald Ford signed the Met
On 06/16/2012 03:21 PM, andy pugh wrote:
> On 16 June 2012 21:25, Peter Blodow wrote:
>
>>> Except that hecto and centi are _not_ prefixes in the SI system.
>> Yes they are. Hekto-, deka-, deci- and centi- (100, 10, 1/10, 1/100
>> rsp.) are the only ones with the decimal exponents not being multip
On 06/16/2012 12:52 PM, Kent A. Reed wrote:
> On 6/16/2012 2:54 PM, andy pugh wrote:
>> On 16 June 2012 18:48, Dave wrote:
> I suspect real estate was also to be a holdout, hell, nobody around here
>>> has a clue what a hectar is, not even me.<<
>>>
>>> I think that Hectars are english also, a
On 06/16/2012 09:41 AM, gene heskett wrote:
> On Saturday, June 16, 2012 12:31:47 PM Peter Blodow did opine:
>
>> Dave,
>> funny thing is that European lathes in those days you were describing,
>> many still working today, were equipped with inch lead screws, so that
>> in order to cut mm threads
Todd Zuercher wrote:
> I think I have found the motors I would like to use.
> http://www.ebay.com/itm/ElectroCraft-XBR-2910-Nema34-Brushless-AC-Servo-
> Motors-w-Encoders-CNC-/221048834843?pt=LH_DefaultDomain_0&hash=item33778
> 98b1b
>
> Now I need to figure out what drives I would like to use and
On 18 June 2012 22:51, Todd Zuercher wrote:
> I think I have found the motors I would like to use.
> http://www.ebay.com/itm/ElectroCraft-XBR-2910-Nema34-Brushless-AC-Servo-
> Motors-w-Encoders-CNC-/221048834843?pt=LH_DefaultDomain_0&hash=item33778
> 98b1b
Do you have a spec? Torque / voltage / c
I think I have found the motors I would like to use.
http://www.ebay.com/itm/ElectroCraft-XBR-2910-Nema34-Brushless-AC-Servo-
Motors-w-Encoders-CNC-/221048834843?pt=LH_DefaultDomain_0&hash=item33778
98b1b
Now I need to figure out what drives I would like to use and the power
supply.
How much wou
Todd Zuercher wrote:
> Trying to get this thread back on topic since it was hijacked by the metric
> system.
>
> To run one of these Keling motors how big would the motor cabling need to be?
> Will it have to be rated for 30 amps? That’s pretty big wire. Or would it
> only need to be rated fo
]
Sent: Friday, June 15, 2012 1:41 PM
To: Enhanced Machine Controller (EMC)
Subject: Re: [Emc-users] Brushless Servo Selection?
On Fri, 2012-06-15 at 10:53 +0100, andy pugh wrote:
> On 15 June 2012 06:58, Viesturs Lācis wrote:
>
> > Unfortunately it requires relatively larger power
On Sunday, June 17, 2012 02:01:11 PM Dave did opine:
> On 6/16/2012 2:54 PM, andy pugh wrote:
> > On 16 June 2012 18:48, Dave wrote:
> I suspect real estate was also to be a holdout, hell, nobody around
> here
> >>
> >> has a clue what a hectar is, not even me.<<
> >>
> >> I think tha
On 6/16/2012 2:54 PM, andy pugh wrote:
> On 16 June 2012 18:48, Dave wrote:
>
I suspect real estate was also to be a holdout, hell, nobody around here
>> has a clue what a hectar is, not even me.<<
>>
>> I think that Hectars are english also, as well as fathoms, etc.
>>
On 17 June 2012 09:09, Steve Blackmore wrote:
> Pipe threads are Imperial Units - BSP (British Standard Pipe) and have a
> Whitworth thread form.
Whitworth thread has a 55 degree thread angle. This is better than a
60 degree angle, but harder to draw.
(Whitworth calculated that 55 degrees gave t
On Sat, 16 Jun 2012 23:03:44 +0300, you wrote:
>2012/6/16 andy pugh :
>>
>> You are quite right, I don't know how I got that wrong.
>> Except that hecto and centi are _not_ prefixes in the SI system.
>>
>
>Could be, I do not know for sure...
>
>BTW the metric vs imperial systems and UK being somew
On Saturday, June 16, 2012 06:46:59 PM andy pugh did opine:
> On 16 June 2012 18:48, Dave wrote:
> >>>I suspect real estate was also to be a holdout, hell, nobody around
> >>>here
> >
> > has a clue what a hectar is, not even me.<<
> >
> > I think that Hectars are english also, as well as fatho
On Saturday, June 16, 2012 06:44:09 PM Dave did opine:
> >>I suspect real estate was also to be a holdout, hell, nobody around
> >>here
>
> has a clue what a hectar is, not even me.<<
>
> I think that Hectars are english also, as well as fathoms, etc.
>
> You need to get your head wrapped aroun
On Saturday, June 16, 2012 06:40:41 PM Mike Bennett did opine:
> Gene
>
> They solved the litres issue in the UK but making it illegal to sell
> most things in anything but metric units. However we still measure
> distance in miles, so what units should we be working out our fuel
> economy? Mil
Viesturs,
don't confuse US and British units although they are both called
imperial units (since when do Americans care about emperors?) - they are
not necessarily the same as you come to details. Screws can be a lot
different, for example. I have an old English combined circular wood saw
and t
On 16 June 2012 21:25, Peter Blodow wrote:
>> Except that hecto and centi are _not_ prefixes in the SI system.
> Yes they are. Hekto-, deka-, deci- and centi- (100, 10, 1/10, 1/100
> rsp.) are the only ones with the decimal exponents not being multiples
> of three,
Wikipedia seems to agree. I w
andy pugh schrieb:
>
> You are quite right, I don't know how I got that wrong.
> Except that hecto and centi are _not_ prefixes in the SI system.
>
>
Yes they are. Hekto-, deka-, deci- and centi- (100, 10, 1/10, 1/100
rsp.) are the only ones with the decimal exponents not being multiples
of th
2012/6/16 andy pugh :
>
> You are quite right, I don't know how I got that wrong.
> Except that hecto and centi are _not_ prefixes in the SI system.
>
Could be, I do not know for sure...
BTW the metric vs imperial systems and UK being somewhere inbetween
(litres from metric system and miles from
On 6/16/2012 2:54 PM, andy pugh wrote:
> On 16 June 2012 18:48, Dave wrote:
I suspect real estate was also to be a holdout, hell, nobody around here
>> has a clue what a hectar is, not even me.<<
>>
>> I think that Hectars are english also, as well as fathoms, etc.
> No, the Hectare is metric
> I know this stuff, I have a physics degree.
>
Sorry, didn't mean to insult you.
> In fact many years ago the NPL invited me along to a colloquium
> discussing how best to re-define the kilogram.
> (Because it is currently based on a lump of platinum-iridium, not on
> any "portable" physical c
On 16 June 2012 20:02, Viesturs Lācis wrote:
> 1/100 is centi - centimeter is 1/100 of meter.
> Hectolitre is 100 litres, so I guess hectare is 100 ares, which means
> that 1 is area of 10x10 m.
You are quite right, I don't know how I got that wrong.
Except that hecto and centi are _not_ prefixe
2012/6/16 John Prentice :
>
>>
>> Fruit machines?? What is a fruit machine?
>>
>> Do you know what we call them in the US?
>>
>> Dave
>
>
> Slot Machine or One arm bandit I think.
The same that look like Mach3 :))
--
Viesturs
If you can't fix it, you don't own it.
http://www.ifixit.com/Manife
2012/6/16 andy pugh :
> On 16 June 2012 18:48, Dave wrote:
I suspect real estate was also to be a holdout, hell, nobody around here
>> has a clue what a hectar is, not even me.<<
>>
>> I think that Hectars are english also, as well as fathoms, etc.
>
> No, the Hectare is metric.
>
> An Are is
On 16 June 2012 18:48, Dave wrote:
>>>I suspect real estate was also to be a holdout, hell, nobody around here
> has a clue what a hectar is, not even me.<<
>
> I think that Hectars are english also, as well as fathoms, etc.
No, the Hectare is metric.
An Are is an area 1km x 1km. A Hectare is 1/
On 6/16/2012 1:45 PM, andy pugh wrote:
> On 16 June 2012 18:05, Jon Elson wrote:
>
>
>> Well, in the US, the metric revolution came and went. Certain
>> industries (aircraft
>> manufacturing and auto manufacturing) have gone totally metric
>>
> Not entirely.
> Part of our ECU code is be
I remember Italy was km/hr years ago. I thought the UK was in km/hr also.
So at this point, I guess it is a safe bet that the UK will not be going
to the Euro anytime soon? ;-)
Dave
On 6/16/2012 1:08 PM, Mike Bennett wrote:
> Gene
>
> They solved the litres issue in the UK but making it ille
>>I suspect real estate was also to be a holdout, hell, nobody around here
has a clue what a hectar is, not even me.<<
I think that Hectars are english also, as well as fathoms, etc.
You need to get your head wrapped around square meters. (Good luck with
that!) I don't have a meter stick, but
On 16 June 2012 18:05, Jon Elson wrote:
> Well, in the US, the metric revolution came and went. Certain
> industries (aircraft
> manufacturing and auto manufacturing) have gone totally metric
Not entirely.
Part of our ECU code is being written by Ford in the USA, to plug into
the code written i
Gene
They solved the litres issue in the UK but making it illegal to sell most
things in anything but metric units. However we still measure distance in
miles, so what units should we be working out our fuel economy? Miles per
litre?
At least we can still buy beer in pints ( 20oz ones of cou
Peter Blodow wrote:
> By the way, how come that in this mailing list everybody speaks in
> inches - you were writing about the metric revolution?
>
Well, in the US, the metric revolution came and went. Certain
industries (aircraft
manufacturing and auto manufacturing) have gone totally metric
On 6/16/2012 12:16 PM, gene heskett wrote:
> On Saturday, June 16, 2012 12:14:55 PM Eric Keller did opine:
>
>
>> On Sat, Jun 16, 2012 at 9:31 AM, Dave wrote:
>>
>>> The school was very unique in that they encouraged students to use the
>>> machines and the facilities after hours. They
On Saturday, June 16, 2012 12:31:47 PM Peter Blodow did opine:
> Dave,
> funny thing is that European lathes in those days you were describing,
> many still working today, were equipped with inch lead screws, so that
> in order to cut mm threads they have to use a 127 teeth gear in the gear
> cas
>>By the way, how come that in this mailing list everybody speaks in
inches - you were writing about the metric revolution?<<
That is the really goofy thing.. the end result was that we are now about half
and half, english and metric.
After the big metric push back in the late 70's, the car comp
On 16 June 2012 17:01, Peter Blodow wrote:
> Andy,
> 1 Pa = 1 N/sq. meter, a very impractical unit.
I know this stuff, I have a physics degree.
In fact many years ago the NPL invited me along to a colloquium
discussing how best to re-define the kilogram.
(Because it is currently based on a lump o
On Saturday, June 16, 2012 12:27:40 PM andy pugh did opine:
> On 15 June 2012 18:40, Kirk Wallace wrote:
> > 48 Volts or rather -48 Volts DC is common for telephone equipment, so
> > there may be cheap supplies available, if one knows where to look.
>
> Very cheap indeed are these "fruit machine
You can't save anybody from himself, but I understand that nobody will
be made responsible for the stupid killing themselves. This is the
consequence of today's "holy law" that nowadays nothing can happen
without someone being responsible (even if nobody really is). Makes a
lot of money for the
On Saturday, June 16, 2012 12:14:55 PM Eric Keller did opine:
> On Sat, Jun 16, 2012 at 9:31 AM, Dave wrote:
> > The school was very unique in that they encouraged students to use the
> > machines and the facilities after hours. They had a shop supervisor
> > who was paid to stay late most weekd
Dave,
funny thing is that European lathes in those days you were describing,
many still working today, were equipped with inch lead screws, so that
in order to cut mm threads they have to use a 127 teeth gear in the gear
case to drive the lead screw. This way, our industry wanted to become
com
Andy,
1 Pa = 1 N/sq. meter, a very impractical unit. Therefore, the "bar" as
the most commonly used pressure unit of today, not a SI unit, is only
accepted as an exception to be near the previously used "atmosphere" = 1
kp/sq.cm.
1 hPa (hectoPascal) = 100 Pa (greek: hekaton = hundred). The heck
>
> Fruit machines?? What is a fruit machine?
>
> Do you know what we call them in the US?
>
> Dave
Slot Machine or One arm bandit I think.
Fruit machine is from graphics commonly used on the rotating drums.
I note the supplies are multi-output switchers. The cross-regulation between
differ
On 6/16/2012 9:46 AM, Eric Keller wrote:
> On Sat, Jun 16, 2012 at 9:31 AM, Dave wrote:
>
>
>> The school was very unique in that they encouraged students to use the
>> machines and the facilities after hours. They had a shop supervisor who
>> was paid to stay late most weekday nights. Even
On 6/16/2012 11:02 AM, andy pugh wrote:
> On 15 June 2012 18:40, Kirk Wallace wrote:
>
>
>> 48 Volts or rather -48 Volts DC is common for telephone equipment, so
>> there may be cheap supplies available, if one knows where to look.
>>
> Very cheap indeed are these "fruit machine" power s
On 15 June 2012 18:40, Kirk Wallace wrote:
> 48 Volts or rather -48 Volts DC is common for telephone equipment, so
> there may be cheap supplies available, if one knows where to look.
Very cheap indeed are these "fruit machine" power supplies:
http://www.ebay.co.uk/itm/261031048815
With 10A at 5
On 16 June 2012 08:22, Peter Blodow wrote:
> To express angular momentum, we have to multiply force by the length of
> the lever, i.e. one meter. So we arrive at the unit DNm = 10 Nm ^= 1
> kpm, and the world is in almost perfect order again.
There is a similar situation with the engine controll
On 16 June 2012 14:46, Eric Keller wrote:
> a mechanical engineering school of any merit should have student
> shops.
We had a machine shop course as part of my Physics degree. The theory
was that we were likely to be having experimental rigs built, and
having some concept of machinability woul
On Sat, Jun 16, 2012 at 9:31 AM, Dave wrote:
>
> The school was very unique in that they encouraged students to use the
> machines and the facilities after hours. They had a shop supervisor who
> was paid to stay late most weekday nights. Even the garage was
> available, so we could put our car
I was in engineering college from 76 to 81 and remember some discussion
about this. Fortunately there was not too much to discuss
as they had already decided that SI was the way to go and we had
recently selected "new" books. At the same time the "metric"
revolution was in full swing and the
On 16 June 2012 08:22, Peter Blodow wrote:
> Now, your dad must have a pretty old car since this cgs system was
> abandoned in 1978. Are you sure that the above explanation is right, or
> is it rather the kiloDekaNewtonMeter?
Thinking back, it was actuality the rating of the variable-speed
gearb
Andy,
way back in my school time, curriculum makers detected that mass and
force are different things. Before, forces were expressed in mass units,
i.e., kilogramms (greek: chilioi = thousand, gramma = weight), and
sometimes called kilogrammforce, which gives roughly identical figures
for compu
On 15.06.12 10:40, Kirk Wallace wrote:
> On Fri, 2012-06-15 at 10:53 +0100, andy pugh wrote:
> > This is a problem with motors like the Keling ones, with a 48V rated
> > voltage.
> > It is far simpler to make a 300V PSU than a 48V one. Simply rectifying
> > mains voltage into a big capacitor makes
On 16 June 2012 00:37, N. Christopher Perry wrote:
> There are about 1.3 Nm to a ft-lb.
Which would reduce confusion no end, except motor manufacturers want
bigger numbers, so like to use oz-inch in the US.
There was a similar tendency in the metric world, but it seems to have
passed. You do occ
There are about 1.3 Nm to a ft-lb.
N. Christopher Perry
On Jun 15, 2012, at 18:40, cogoman wrote:
> On 06/14/2012 10:33 PM, Jon Elson wrote:
>> Thats inch-POUNDS! 16 times inch-Ounces.
>> 56 In-Lb is 896 Oz-In, so you have made a mistake. Also, steppers,
>> ESPECIALLY
> Thanks. I don't have
On 15 June 2012 23:40, cogoman wrote:
> Thanks. I don't have an intuitive feeling for N-m measures,
As a comparison, the triple stack NEMA 23 steppers are up to 3Nm.
--
atp
If you can't fix it, you don't own it.
http://www.ifixit.com/Manifesto
On 06/14/2012 10:33 PM, Jon Elson wrote:
> Thats inch-POUNDS! 16 times inch-Ounces.
> 56 In-Lb is 896 Oz-In, so you have made a mistake. Also, steppers,
> ESPECIALLY
Thanks. I don't have an intuitive feeling for N-m measures, so for
quite a while I have been making this mistake in my head. I h
On 15 June 2012 18:40, Kirk Wallace wrote:
> Another thing I haven't had time to look into is using a Delon doubler
> when one needs higher voltage than what is at hand.
> http://en.wikipedia.org/wiki/File:Bridge_voltage_doubler.svg
> http://en.wikipedia.org/wiki/Voltage_doubler
Yes, I built a d
2012/6/15 Fox Mulder :
>
> The datasheet shows that it has two 32V and one 18V and one 12V output
> (Makes in total 4).
> On each of the 32V lines you can have up to 23.4A and both other 2A.
Thank You! I somehow missed the presence of datasheet.
--
Viesturs
If you can't fix it, you don't own it
Am 15.06.2012 19:58, schrieb Viesturs Lācis:
> 2012/6/15 Kirk Wallace :
>>
>> Building an Antek supply shouldn't be too expensive, but I haven't
>> checked prices recently.
>> http://www.antekinc.com/index.php
>> http://www.antekinc.com/gview.php
>>
>
> Thanks for the links! 155$ is little more th
2012/6/15 Kirk Wallace :
>
> Building an Antek supply shouldn't be too expensive, but I haven't
> checked prices recently.
> http://www.antekinc.com/index.php
> http://www.antekinc.com/gview.php
>
Thanks for the links! 155$ is little more that I would like,
especially if it is a shipment from US -
2012/6/15 andy pugh :
> On 15 June 2012 06:58, Viesturs Lācis wrote:
>
>> Unfortunately it requires relatively larger power supply with higher
>> current output.
>
> This is a problem with motors like the Keling ones, with a 48V rated voltage.
> It is far simpler to make a 300V PSU than a 48V one.
On Fri, 2012-06-15 at 10:53 +0100, andy pugh wrote:
> On 15 June 2012 06:58, Viesturs Lācis wrote:
>
> > Unfortunately it requires relatively larger power supply with higher
> > current output.
>
> This is a problem with motors like the Keling ones, with a 48V rated voltage.
> It is far simpler
Elson [mailto:el...@pico-systems.com]
Sent: Thursday, June 14, 2012 10:33 PM
To: Enhanced Machine Controller (EMC)
Subject: Re: [Emc-users] Brushless Servo Selection?
cogoman wrote:
>450 Oz-in. steppers are pretty hefty devices.
>I followed the link to the Keling website, and the he
On 15 June 2012 06:58, Viesturs Lācis wrote:
> Unfortunately it requires relatively larger power supply with higher
> current output.
This is a problem with motors like the Keling ones, with a 48V rated voltage.
It is far simpler to make a 300V PSU than a 48V one. Simply rectifying
mains voltage
2012/6/13 Todd Zuercher :
>
> I was thinking of picking up some AMC servo drives off ebay (BE12A6
> drives seem to be cheep and plentiful there).
Mesa 8i20 is cheaper, do not know about Pico drives.
And paired with KL34BLS-98 ($134/pcs) servo motor it should be a good
match: motor has peak curren
cogoman wrote:
>450 Oz-in. steppers are pretty hefty devices.
>I followed the link to the Keling website, and the heftiest motor
> they listed was a maximum of 6.3N.m, which I assume (correct me if I'm
> wrong) means Newton-Meters. The conversion calculator I used gave me 56
> inch poun
I'm concerned that you are about to make a mistake, and waste a lot of
money.
450 Oz-in. steppers are pretty hefty devices. The mill we use at
work has servo motors rated for approximately 500 oz-in. maximum, and
they are expensive to replace. These have all the grunt we need for a
lot of
On 13 June 2012 16:48, Todd Zuercher wrote:
> I was thinking of picking up some AMC servo drives off ebay (BE12A6
> drives seem to be cheep and plentiful there). And run about a 400W
> motor of some sort. I think I would like to use a Mesa 5i25 for
> controlling it all (is that a good choice?).
I am thinking about trying to upgrade some old routers from steppers to
servos. I am seeking advice on a good and inexpensive BLDC motor to
use.
The steppers on them now are NEMA 34 with a 3/8" shaft, rated at 7amp
and 450 oz-in. and are half stepping from an old Anaheim Automation
unipolar bi
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