information on internal working of electronic sensors...

[Don Y]

On 10/27/2022 1:56 PM, Fred Bloggs wrote:

On Thursday, October 27, 2022 at 2:52:58 PM UTC-4, Don Y wrote:
On 10/27/2022 11:17 AM, Fred Bloggs wrote:
On Thursday, October 27, 2022 at 4:32:22 AM UTC-4, Don Y wrote:
On 10/26/2022 11:30 PM, kristoff wrote:
On the 27th of November, there is \"de dag van de wetenschap\" (the
day of science) here in Belgium, and I am helping out a local fablab
on this event.

This event is aimed at kids between 14 and 18. I help out in the
\"electronics corner\"

We are working on a setup where we want to show all kind of
electronic sensors. To link electronics with science, The idea is to
provide the visitor with a description of the internal working of a
sensor, and let them find the correct sensor in the batch.
That may be hard -- unless you deliberately \"load the deck\" in favor
of such discoveries because the \"internals\" of many aren\'t readily
apparent.

For example, a Hall Effect sensor can physically look like a
temperature sensor (depending on the technology being used) with the
only difference being the actual part numbers on the devices.
So I am looking for information on the internal working of
different kind of sensors. For certain sensors, it is well known
(hall-sensor, light-sensor, ... ) and in certain cases it is
described in the datasheets (laser-based CO2-sensor or fine-particle
dust-sensor).

But I am looking for information on the following sensors / devices:
- temperature sensors - air humidity - gas (CO, VOC) that are not
based on lasers - hardware based gyroscopes
If you only want the participants to *visually* examine the devices
to ascertain their intent, perhaps you might want to pick a different
set of sensors and technologies?

E.g., an LVDT can typically be recognized as sensing
displacement/position owing to it\'s shape and the motion of the
sensing core. An RVDT or syncro resolver for rotational position hints
at its role by the presence of the rotatable shaft. A dew point sensor
(related to humidity) can be recognized by the presence of the mirror.
A pressure sensor by a \"port\" into the device (to which you could
attach a length of hose to draw attention to that).

You could affix the sensor to an assembly to further hint at the role
that it plays. And, for a more interesting display, configure the
sensor to an *indicator* so that students can manipulate the mechanism
to see the sensor take effect and get a feel for how sensitive it may
be.

He can do a demonstration for the students with this marvel:

SawStop Safety System stops on contact with skin

https://www.sawstop.com/product/compact-table-saw/

The product price must reflect the liability insurance. They\'ve been in
business for a quite a while. Protecting the hands is a very tricky
challenge because things happen so fast and the hands are surprisingly
vulnerable to nerve damage making them unusable despite being fully
intact.
If its the system I\'ve seen, it\'s a one-time event; you have to replace
the \"module\" whenever it has been \"exercised\".

Yeah? How often do you expect it to be exercised? You\'re not going to
non-destructively stop a 4,000 RPM rotating saw blade in under 5 ms without
damage.

Local Maker House is often complaining about it \"activating\" too often
(as the replacement \"cartridges\" aren\'t cheap for a group that is
perpetually worrying about how to pay rent -- apparently a common problem
in member funded maker houses)

Regardless, the mechanism by which it works wouldn\'t be obvious. SEEING
something work and UNDERSTANDING why it works are very different.

Not why it works, how it works. Demonstration testing uses a hot dog to
simulate human flesh. It stops the saw instantaneously with an sacrificial
interference brake. Looks like you need to replace the saw blade in addition
to the brake cartridge. Reckless people can\'t afford to own this machine.

But the OP wants the attendees to understand HOW the sensors \"do their
thing\"

Hence the other examples (elsewhere) I\'ve given; you can grok how they
work, on casual inspection.

grok? ookay...

Perhaps you\'re too young to have been exposed to the literature?

<https://en.wikipedia.org/wiki/Grok>

Different term than \"understand\".

 

[Lasse Langwadt Christensen]

fredag den 28. oktober 2022 kl. 00.14.41 UTC+2 skrev Don Y:

On 10/27/2022 1:56 PM, Fred Bloggs wrote:
On Thursday, October 27, 2022 at 2:52:58 PM UTC-4, Don Y wrote:
On 10/27/2022 11:17 AM, Fred Bloggs wrote:
On Thursday, October 27, 2022 at 4:32:22 AM UTC-4, Don Y wrote:
On 10/26/2022 11:30 PM, kristoff wrote:
On the 27th of November, there is \"de dag van de wetenschap\" (the
day of science) here in Belgium, and I am helping out a local fablab
on this event.

This event is aimed at kids between 14 and 18. I help out in the
\"electronics corner\"

We are working on a setup where we want to show all kind of
electronic sensors. To link electronics with science, The idea is to
provide the visitor with a description of the internal working of a
sensor, and let them find the correct sensor in the batch.
That may be hard -- unless you deliberately \"load the deck\" in favor
of such discoveries because the \"internals\" of many aren\'t readily
apparent.

For example, a Hall Effect sensor can physically look like a
temperature sensor (depending on the technology being used) with the
only difference being the actual part numbers on the devices.
So I am looking for information on the internal working of
different kind of sensors. For certain sensors, it is well known
(hall-sensor, light-sensor, ... ) and in certain cases it is
described in the datasheets (laser-based CO2-sensor or fine-particle
dust-sensor).

But I am looking for information on the following sensors / devices:
- temperature sensors - air humidity - gas (CO, VOC) that are not
based on lasers - hardware based gyroscopes
If you only want the participants to *visually* examine the devices
to ascertain their intent, perhaps you might want to pick a different
set of sensors and technologies?

E.g., an LVDT can typically be recognized as sensing
displacement/position owing to it\'s shape and the motion of the
sensing core. An RVDT or syncro resolver for rotational position hints
at its role by the presence of the rotatable shaft. A dew point sensor
(related to humidity) can be recognized by the presence of the mirror.
A pressure sensor by a \"port\" into the device (to which you could
attach a length of hose to draw attention to that).

You could affix the sensor to an assembly to further hint at the role
that it plays. And, for a more interesting display, configure the
sensor to an *indicator* so that students can manipulate the mechanism
to see the sensor take effect and get a feel for how sensitive it may
be.

He can do a demonstration for the students with this marvel:

SawStop Safety System stops on contact with skin

https://www.sawstop.com/product/compact-table-saw/

The product price must reflect the liability insurance. They\'ve been in
business for a quite a while. Protecting the hands is a very tricky
challenge because things happen so fast and the hands are surprisingly
vulnerable to nerve damage making them unusable despite being fully
intact.
If its the system I\'ve seen, it\'s a one-time event; you have to replace
the \"module\" whenever it has been \"exercised\".

Yeah? How often do you expect it to be exercised? You\'re not going to
non-destructively stop a 4,000 RPM rotating saw blade in under 5 ms without
damage.
Local Maker House is often complaining about it \"activating\" too often
(as the replacement \"cartridges\" aren\'t cheap for a group that is
perpetually worrying about how to pay rent -- apparently a common problem
in member funded maker houses)

they don\'t make people pay for triggering it? they either avoided injury or did
something dumb (it has a test mode to test if something will trigger it)

or have people pay a small fee to a cartridge fund if they want to use the tablesaw

 

[Don Y]

On 10/27/2022 3:31 PM, Lasse Langwadt Christensen wrote:

fredag den 28. oktober 2022 kl. 00.14.41 UTC+2 skrev Don Y:

Local Maker House is often complaining about it \"activating\" too often
(as the replacement \"cartridges\" aren\'t cheap for a group that is
perpetually worrying about how to pay rent -- apparently a common problem
in member funded maker houses)

they don\'t make people pay for triggering it? they either avoided injury or did
something dumb (it has a test mode to test if something will trigger it)

No. Everyone is supposed to have been trained before using each piece
of equipment. And, a \"shop manager\" (one for each different shop) is supposed
to be on hand when anything in that shop is in use.

> or have people pay a small fee to a cartridge fund if they want to use the tablesaw

I don\'t set policy (I\'m not even a member as they have nothing that I need).
I think they likely fear that associating additional POTENTIAL costs with
items will discourage use and, thus, membership.

I don\'t really understand how they can keep the doors open at $50/member/month,
given that most folks \"have a life\" and can\'t make extensive use of their
facilities. Would you want to drive across town (30+ minutes for me) to
use a tool(s) for an hour or so, then drive back home (with your \"project\")
again... only to repeat the effort the next time you need another tool?

Why not take the monies and buy your own tools??

(Of course, {metal,wood}-lathe or mill might be out of reach but you
don\'t *need* a table saw to cut wood, etc.)

 

[Lasse Langwadt Christensen]

fredag den 28. oktober 2022 kl. 00.47.17 UTC+2 skrev Don Y:

On 10/27/2022 3:31 PM, Lasse Langwadt Christensen wrote:
fredag den 28. oktober 2022 kl. 00.14.41 UTC+2 skrev Don Y:

Local Maker House is often complaining about it \"activating\" too often
(as the replacement \"cartridges\" aren\'t cheap for a group that is
perpetually worrying about how to pay rent -- apparently a common problem
in member funded maker houses)

they don\'t make people pay for triggering it? they either avoided injury or did
something dumb (it has a test mode to test if something will trigger it)
No. Everyone is supposed to have been trained before using each piece
of equipment. And, a \"shop manager\" (one for each different shop) is supposed
to be on hand when anything in that shop is in use.
or have people pay a small fee to a cartridge fund if they want to use the tablesaw
I don\'t set policy (I\'m not even a member as they have nothing that I need).
I think they likely fear that associating additional POTENTIAL costs with
items will discourage use and, thus, membership.

I don\'t really understand how they can keep the doors open at $50/member/month,

There\'s a makerspace here it is ~$20/month half price for students
Though they don\'t pay rent the location is provided by the municipality and I think they
also get some subsidies by the government, like other non-profit organizations with an educational purpose

given that most folks \"have a life\" and can\'t make extensive use of their
facilities. Would you want to drive across town (30+ minutes for me) to
use a tool(s) for an hour or so, then drive back home (with your \"project\")
again... only to repeat the effort the next time you need another tool?

yeh, you have to plan ahead

Why not take the monies and buy your own tools??

(Of course, {metal,wood}-lathe or mill might be out of reach but you
don\'t *need* a table saw to cut wood, etc.)

you don\'t _need_ most tools, but they make it a lot easier
and $50 is going to takes years to buy a decent metal lathe or table say

 

[Don Y]

On 10/27/2022 4:18 PM, Lasse Langwadt Christensen wrote:

I don\'t set policy (I\'m not even a member as they have nothing that I
need). I think they likely fear that associating additional POTENTIAL
costs with items will discourage use and, thus, membership.

I don\'t really understand how they can keep the doors open at
$50/member/month,

There\'s a makerspace here it is ~$20/month half price for students Though
they don\'t pay rent the location is provided by the municipality and I think
they also get some subsidies by the government, like other non-profit
organizations with an educational purpose

Not the case, here. You pay rent. You pay your own utilities.
You pay for your own liability insurance. etc.

You can *apply* for grants (both from the gummit and other
\"benevolent organizations\") but there are no guarantees as
you are competing with other people for a fixed size pot of money.

I\'m sure the $50 was determined based on \"average membership\"
(which can vary month-to-month) and \"operating costs\" -- I
don\'t think there are any \"paid staff\" though there may be
some services -- accounting, legal, etc. -- that have to
be compensated with currency (instead of in-kind).

given that most folks \"have a life\" and can\'t make extensive use of their
facilities. Would you want to drive across town (30+ minutes for me) to
use a tool(s) for an hour or so, then drive back home (with your
\"project\") again... only to repeat the effort the next time you need
another tool?

yeh, you have to plan ahead

So, folks bu a monthly (or quarterly) membership when they are
ready to START work on their \"project\". And, hope to complete it
before their purchase needs renewal. The organization can\'t
count on them as an ongoing source of funds (unless they are
constantly coming up with new \"projects\")

I looked into them for their laser cutter. Then, realized an easier
way of achieving the same result without that tool.

Likewise, their 3D printers -- why spend an evening watching one of
theirs print a part when I can just send off the design to a service
bureau and go about my daily business while the parts are made?

Why not take the monies and buy your own tools??

(Of course, {metal,wood}-lathe or mill might be out of reach but you don\'t
*need* a table saw to cut wood, etc.)

you don\'t _need_ most tools, but they make it a lot easier and $50 is going
to takes years to buy a decent metal lathe or table say

But are YOU going to want a lathe? Do YOU *need* that table saw?
Or, can you do the same thing with a saw guide, circular saw and
a brand new blade? Without having to transport your work pieces
to and fro?

I see lots of members are college students, likely not having to
worry about \"families\" expecting them home for dinner, etc.
And, if not \"party goers\", it may be the only real social outlet
that they have available.

I suspect some volunteer their time in exchange for \"membership time\"
(especially if they are using the place as a social outlet).

Can\'t imagine a husband-father spending any more time there than
absolutely essential. And, having to justify to family his $50/month
\"habit\". (I guess it\'s cheaper than drinking or smoking but how
many nights do you think the wife would want to be \"stuck\" with the kids?)

 

[Don Y]

On 10/27/2022 4:54 PM, Don Y wrote:

Can\'t imagine a husband-father spending any more time there than
absolutely essential.  And, having to justify to family his $50/month
\"habit\".  (I guess it\'s cheaper than drinking or smoking but how
many nights do you think the wife would want to be \"stuck\" with the kids?)

For example, I spent an hour there, initially, getting a tour and
sitting through a staff meeting (to get an idea of the issues that
they were facing). So, I\'ve got an hour of travel time (30+30)
and an hour \"there\" invested -- before I even THINK I may want to
participate.

Then, a course on use of the laser cutter. Another hour of travel,
an hour of class -- plus a \"small donation\".

Before I can be \"authorized\" to use the laser cutter, I must
make a \"name plate\" that will be hung alongside the laser printer
to indicate I am a \"trained user\". So, another hour of travel
plus, likely, a (supervised) hour making something that I am going
to leave behind (i.e., I am no \"better off\" having made it!).

So, I\'m 6 hours invested and now just ALLOWED to *compete* for
time on the laser cutter.

Instead, spend those last two hours researching service bureaus that
can do what I want -- or, find an alternative way of getting it done!
And, consider the preceding 4 hours a \"learning experience\".

 

[Lasse Langwadt Christensen]

fredag den 28. oktober 2022 kl. 02.05.05 UTC+2 skrev Don Y:

On 10/27/2022 4:54 PM, Don Y wrote:
Can\'t imagine a husband-father spending any more time there than
absolutely essential. And, having to justify to family his $50/month
\"habit\". (I guess it\'s cheaper than drinking or smoking but how
many nights do you think the wife would want to be \"stuck\" with the kids?)
For example, I spent an hour there, initially, getting a tour and
sitting through a staff meeting (to get an idea of the issues that
they were facing). So, I\'ve got an hour of travel time (30+30)
and an hour \"there\" invested -- before I even THINK I may want to
participate.

Then, a course on use of the laser cutter. Another hour of travel,
an hour of class -- plus a \"small donation\".

Before I can be \"authorized\" to use the laser cutter, I must
make a \"name plate\" that will be hung alongside the laser printer
to indicate I am a \"trained user\". So, another hour of travel
plus, likely, a (supervised) hour making something that I am going
to leave behind (i.e., I am no \"better off\" having made it!).

So, I\'m 6 hours invested and now just ALLOWED to *compete* for
time on the laser cutter.

Instead, spend those last two hours researching service bureaus that
can do what I want -- or, find an alternative way of getting it done!
And, consider the preceding 4 hours a \"learning experience\".

consider it a more social alternative to spending hours alone in front
of a computer writing pages of text on newsgroups

 

[Don Y]

On 10/27/2022 5:13 PM, Lasse Langwadt Christensen wrote:

fredag den 28. oktober 2022 kl. 02.05.05 UTC+2 skrev Don Y:
On 10/27/2022 4:54 PM, Don Y wrote:
Can\'t imagine a husband-father spending any more time there than
absolutely essential. And, having to justify to family his $50/month
\"habit\". (I guess it\'s cheaper than drinking or smoking but how
many nights do you think the wife would want to be \"stuck\" with the kids?)
For example, I spent an hour there, initially, getting a tour and
sitting through a staff meeting (to get an idea of the issues that
they were facing). So, I\'ve got an hour of travel time (30+30)
and an hour \"there\" invested -- before I even THINK I may want to
participate.

Then, a course on use of the laser cutter. Another hour of travel,
an hour of class -- plus a \"small donation\".

Before I can be \"authorized\" to use the laser cutter, I must
make a \"name plate\" that will be hung alongside the laser printer
to indicate I am a \"trained user\". So, another hour of travel
plus, likely, a (supervised) hour making something that I am going
to leave behind (i.e., I am no \"better off\" having made it!).

So, I\'m 6 hours invested and now just ALLOWED to *compete* for
time on the laser cutter.

Instead, spend those last two hours researching service bureaus that
can do what I want -- or, find an alternative way of getting it done!
And, consider the preceding 4 hours a \"learning experience\".

consider it a more social alternative to spending hours alone in front
of a computer writing pages of text on newsgroups

Or, spending hours each week visiting neighbors in the neighborhood?

 

[Lasse Langwadt Christensen]

fredag den 28. oktober 2022 kl. 02.35.16 UTC+2 skrev Don Y:

On 10/27/2022 5:13 PM, Lasse Langwadt Christensen wrote:
fredag den 28. oktober 2022 kl. 02.05.05 UTC+2 skrev Don Y:
On 10/27/2022 4:54 PM, Don Y wrote:
Can\'t imagine a husband-father spending any more time there than
absolutely essential. And, having to justify to family his $50/month
\"habit\". (I guess it\'s cheaper than drinking or smoking but how
many nights do you think the wife would want to be \"stuck\" with the kids?)
For example, I spent an hour there, initially, getting a tour and
sitting through a staff meeting (to get an idea of the issues that
they were facing). So, I\'ve got an hour of travel time (30+30)
and an hour \"there\" invested -- before I even THINK I may want to
participate.

Then, a course on use of the laser cutter. Another hour of travel,
an hour of class -- plus a \"small donation\".

Before I can be \"authorized\" to use the laser cutter, I must
make a \"name plate\" that will be hung alongside the laser printer
to indicate I am a \"trained user\". So, another hour of travel
plus, likely, a (supervised) hour making something that I am going
to leave behind (i.e., I am no \"better off\" having made it!).

So, I\'m 6 hours invested and now just ALLOWED to *compete* for
time on the laser cutter.

Instead, spend those last two hours researching service bureaus that
can do what I want -- or, find an alternative way of getting it done!
And, consider the preceding 4 hours a \"learning experience\".

consider it a more social alternative to spending hours alone in front
of a computer writing pages of text on newsgroups
Or, spending hours each week visiting neighbors in the neighborhood?

same thing

 

[Don Y]

On 10/27/2022 5:46 PM, Lasse Langwadt Christensen wrote:

fredag den 28. oktober 2022 kl. 02.35.16 UTC+2 skrev Don Y:
On 10/27/2022 5:13 PM, Lasse Langwadt Christensen wrote:
fredag den 28. oktober 2022 kl. 02.05.05 UTC+2 skrev Don Y:
On 10/27/2022 4:54 PM, Don Y wrote:
Can\'t imagine a husband-father spending any more time there than
absolutely essential. And, having to justify to family his $50/month
\"habit\". (I guess it\'s cheaper than drinking or smoking but how
many nights do you think the wife would want to be \"stuck\" with the kids?)
For example, I spent an hour there, initially, getting a tour and
sitting through a staff meeting (to get an idea of the issues that
they were facing). So, I\'ve got an hour of travel time (30+30)
and an hour \"there\" invested -- before I even THINK I may want to
participate.

Then, a course on use of the laser cutter. Another hour of travel,
an hour of class -- plus a \"small donation\".

Before I can be \"authorized\" to use the laser cutter, I must
make a \"name plate\" that will be hung alongside the laser printer
to indicate I am a \"trained user\". So, another hour of travel
plus, likely, a (supervised) hour making something that I am going
to leave behind (i.e., I am no \"better off\" having made it!).

So, I\'m 6 hours invested and now just ALLOWED to *compete* for
time on the laser cutter.

Instead, spend those last two hours researching service bureaus that
can do what I want -- or, find an alternative way of getting it done!
And, consider the preceding 4 hours a \"learning experience\".

consider it a more social alternative to spending hours alone in front
of a computer writing pages of text on newsgroups
Or, spending hours each week visiting neighbors in the neighborhood?

same thing

No. Checking USENET (and email) while monitoring downloads can be
considered \"productive use of time\". Especially if, unchecked, the
downloads can exhaust the available disk space on the machine!

Visiting neighbors is just a social activity; nothing gets \"checked
off your (ToDo) list\".

 

[Jan Panteltje]

On a sunny day (Thu, 27 Oct 2022 19:02:51 +0200) it happened Jeroen Belleman
<jeroen@nospam.please> wrote in <tjedjs$9kg$1@gioia.aioe.org>:

I made this cork gun with a piece of steel pipe and a spark plug.
Two drops of gas would pop the cork many meters into the air, but
one or three drops would do nothing.

My highschool physics teacher did electrolysis by sending a current through water,
then blew soap bubbles with the mixture H2 and O gas, and had us detonate the bubbles that floated
in the auditorium with a lighted match.
You quickly find out that the content and explosive force goes up exponentially with the bubble size.
He also filled a steal pipe with spark plug with the gas and then once shot a hole in the glass cabinet at the back of the auditorium
I would usually find a place a bit back from his experiments,
The voltage for the sparkplug came from his Ruhmkorff coil demo on the same table.

The other physics teacher had part of a finger missing from one of his experiments....
He had us calculate nukes, critical mass etc

 

[Martin Brown]

On 27/10/2022 23:47, Don Y wrote:

On 10/27/2022 3:31 PM, Lasse Langwadt Christensen wrote:
fredag den 28. oktober 2022 kl. 00.14.41 UTC+2 skrev Don Y:

Local Maker House is often complaining about it \"activating\" too often
(as the replacement \"cartridges\" aren\'t cheap for a group that is
perpetually worrying about how to pay rent -- apparently a common
problem
in member funded maker houses)

they don\'t make people pay for triggering it? they either avoided
injury or did
something dumb (it has a test mode to test if something will trigger it)

No.  Everyone is supposed to have been trained before using each piece
of equipment.  And, a \"shop manager\" (one for each different shop) is
supposed
to be on hand when anything in that shop is in use.

or have people pay a small fee to a cartridge fund if they want to use
the tablesaw

I don\'t set policy (I\'m not even a member as they have nothing that I
need).
I think they likely fear that associating additional POTENTIAL costs with
items will discourage use and, thus, membership.

I don\'t really understand how they can keep the doors open at
$50/member/month,
given that most folks \"have a life\" and can\'t make extensive use of their
facilities.  Would you want to drive across town (30+ minutes for me) to
use a tool(s) for an hour or so, then drive back home (with your \"project\")
again... only to repeat the effort the next time you need another tool?

It depends what you are trying to do and what kit the makerspace
actually has. One of the ones about an hour from me has had laser
cutters and a professional 3D printer long before they were common. They
also had some CNC stuff and the blue wax for learning to use them and/or
making lost wax casting moulds from.

Some of their kit was a bit wasted as most members were university
students on a discount wanting to make their own electric guitars. Power
band saws and sanders were in high demand as were spray paint booths.

Location was a bit dismal - think Bladerunner crossed with \"Get Smart\".
That much kit in a rather run down cheap rent area takes some defending.
Most of the other parts of the former cotton mill building were let out
as band practice rooms. Electronics capabilities were a bit basic.

Why not take the monies and buy your own tools??

(Of course, {metal,wood}-lathe or mill might be out of reach but you
don\'t *need* a table saw to cut wood, etc.)

I have a 10\" metal lathe at home and a table saw (with no safety
features at all). The latter tends to trip the house RCD though - I
think its motor is on it\'s last legs (or whatever motors stand on).

But for access to exotic would otherwise be unaffordable kit and
spending a day using it then yes a trip to a makerspace can be
worthwhile. It isn\'t unless you plan what you will do when there.

I don\'t belong to one at the moment though.

--
Regards,
Martin Brown

 

[Don Y]

On 10/28/2022 2:05 AM, Martin Brown wrote:

I don\'t really understand how they can keep the doors open at $50/member/month,
given that most folks \"have a life\" and can\'t make extensive use of their
facilities.  Would you want to drive across town (30+ minutes for me) to
use a tool(s) for an hour or so, then drive back home (with your \"project\")
again... only to repeat the effort the next time you need another tool?

It depends what you are trying to do and what kit the makerspace actually has.
One of the ones about an hour from me has had laser cutters and a professional
3D printer long before they were common. They also had some CNC stuff and the
blue wax for learning to use them and/or making lost wax casting moulds from.

Aside from a Bridgeport, bandsaw and metal/wood lathes, there\'s nothing
really exotic (laser cutting can be outsourced commercially as can 3D
printing). Lots of (power) hand tools but, again, nothing I wouldn\'t
already have (working for a tool company let me accumulate a LOT of tools!)

They\'ve got a Mantis, \'scope, ARB, a few irons, and an assortment of \"parts\"
but I\'m already covered on that score.

A fair bit of kit for making jewelry -- but, not anything in which I\'d have
an interest.

They have various bits of software (I assume with valid licenses?) but I\'ve
likely got similar (though likely older releases).

I\'d have been more interested if they had a brake and other sheet metal
forming kit but that\'s not likely to materialize anytime soon. Spot welder
would have been a sure sell!

Some of their kit was a bit wasted as most members were university students on
a discount wanting to make their own electric guitars. Power band saws and
sanders were in high demand as were spray paint booths.

Yup. Guitars and bicycles seem to be the most common projects. A few older
folks working on bits of furniture -- wine racks, decorative benches, etc.
And, a pen-turning class.

Location was a bit dismal - think Bladerunner crossed with \"Get Smart\". That
much kit in a rather run down cheap rent area takes some defending. Most of the
other parts of the former cotton mill building were let out as band practice
rooms. Electronics capabilities were a bit basic.

Yes, this is located *on* a railroad track, no real parking, \"seedy\" part of
town, etc. So, bringing your vehicle there could represent a risk. With
limited funds, they tend to be bottom feeders when it comes to \"settling\"
for a location.

Why not take the monies and buy your own tools??

(Of course, {metal,wood}-lathe or mill might be out of reach but you
don\'t *need* a table saw to cut wood, etc.)

I have a 10\" metal lathe at home and a table saw (with no safety features at
all). The latter tends to trip the house RCD though - I think its motor is on
it\'s last legs (or whatever motors stand on).

Guy on the street behind me has a metal lathe. Another guy on *my* street
has a wood one. A friend has converted his 3rd garage into an upscale woodshop
(he\'s the sort who will take weeks to make a foot stool as he has to hand
rub the finish, etc.)

But for access to exotic would otherwise be unaffordable kit and spending a day
using it then yes a trip to a makerspace can be worthwhile. It isn\'t unless you
plan what you will do when there.

But even unaffordable kit can be accessed, for a price, via service bureaus.
Or, \"friends\" with the kit you need. In each of these cases, the added
benefit is they already KNOW how to best utilize the kit whereas you\'re
just floundering! Time saved + experience available has some financial
value -- especially if you care about the quality of the result!

That\'s how I\'ve had all of my sheetmetal projects and injection molds
handled... I\'m not going to \"save\" anything by even attempting them
myself (and the skillsets learned will have no further value to me)

> I don\'t belong to one at the moment though.

 

[kristoff]

Hi Martin, all,


First, it looks like my small question on sensors seems to have turned
into quit an interesting discussion.

I will try to answer some of the \"sensor\" remarks later on.



Some remarks concerning fablab / makerspace.

Op 28.10.22 om 11:05 schreef Martin Brown:

I don\'t really understand how they can keep the doors open at
$50/member/month,
given that most folks \"have a life\" and can\'t make extensive use of their
facilities.  Would you want to drive across town (30+ minutes for me) to
use a tool(s) for an hour or so, then drive back home (with your
\"project\")
again... only to repeat the effort the next time you need another tool?

It depends what you are trying to do and what kit the makerspace
actually has. One of the ones about an hour from me has had laser
cutters and a professional 3D printer long before they were common. They
also had some CNC stuff and the blue wax for learning to use them and/or
making lost wax casting moulds from.

One of the things I do when I visit a city, is to visit the local
makerspaces / fablab / hackerspaces and have a chat with the people
overthere.

It\'s always a good way to learn about a city, because you get to meet
people who really live there.



First, one note:

there is quite a difference between the different types of
organizations: hackerspace / fablab / makerspace.
Some are mainly about \"making equipment available\", others are more a
\"social space\" for like-minded people.

In some, everybody just does their own thing, in other, \"sharing
knowledge\" is more important.




I\'ll use the term \"space\" here in a general sense.

In general, I see two reasons why people join a space:

1/ Using the equipment of the space.

And, for that, there can be two reasons:
- price, in combination with the amount of time you actually use it.
Some of this equipment is simply way too expensive especially if you
just use it not that much.

- Place.
Especially in a big city, people live in a small apartment, and simply
do not have the place to install all the equipment they need.

If you hobby requires you to have place and be able to make a lot of
noise / dust / <whatever> , the 40 euro / month membership of space is
still quite cheap compared to renting a garage to store your stuff.



2/ The social element.

Especially in spaces who have more a culture of sharing knowledge,
having other people around you who can help you, is always a good thing.




In certain spaces, giving workshops is just seen as \"a way to make
money, so to keep the space running\".

In other space, giving a workshop is more about \"some people getting
together to try out something together\".



So it all differs from space to space.

A couple of years ago, I was talking to somebody why they had a 3D
printer in their hackerspace. (that was when a 3D printer was still 800
euro or so).


He said \"in a hackerspace, we have a 3D printer for two reasons: to
allow people to learn about 3D printing and 3D design, and to print out
a few small object if needed..

But if you do a project where you need -say- 40 pieces of the same
thing, don\'t do it here. Go to a fablab\".



I find this a good example of the different types of spaces, the
different reasons why they exist and, hence, the different reasons why
people join them.


Kr.

 

[Don Y]

On 10/28/2022 9:26 AM, kristoff wrote:

One of the things I do when I visit a city, is to visit the local makerspaces /
fablab / hackerspaces and have a chat with the people overthere.

It\'s always a good way to learn about a city, because you get to meet people
who really live there.

You get to chat with a SUBpopulation of people who live there -- even if their
residencies are only temporary (e.g., students who \"move on\" in < 4 years).
You aren\'t *likely* (though it is still possible) to meet any doctors,
lawyers, many women (though ours has a program targeting women), etc. I.e.,
you\'re most likely to encounter people who want -- or need -- to access such
a space.

[Go to a blood donation location and you\'re most likely to meet blood donors!]

First, one note:

there is quite a difference between the different types of organizations:
hackerspace / fablab / makerspace.
Some are mainly about \"making equipment available\", others are more a \"social
space\" for like-minded people.

In some, everybody just does their own thing, in other, \"sharing knowledge\" is
more important.

A lot of that depends on the types of people that it attracts. E.g., If you
have lots of students (likely from the same school!), then they are more
likely to have OTHER common interests -- the local sports teams, the same
professors, dormitories, etc. -- even FRIENDS!

In a metro area of ~1M, it\'s very likely that non-students don\'t even
share the same ZIP (postal) code, let alone any of these other things.
(Hence my 30+ minute commute to the local space)

I\'ll use the term \"space\" here in a general sense.

In general, I see two reasons why people join a space:

1/ Using the equipment of the space.

And, for that, there can be two reasons:
- price, in combination with the amount of time you actually use it.
Some of this equipment is simply way too expensive especially if you just use
it not that much.

The downside of that, for the \"space\", is that it is unlikely the patron will
have an ongoing need for the equipment -- unless he is constantly involved with
new projects. And, in that case, would likely have an eye towards acquiring
the equipment that he needs as he is confident of a FUTURE need.

We don\'t have basements, here, so it is fairly common for people to convert
one of their garage bays into a shop. Or, a spare bedroom, depending on the
nature of the activities (many \"empty nesters\" with 1 to 3 extra bedrooms)

- Place.
Especially in a big city, people live in a small apartment, and simply do not
have the place to install all the equipment they need.

If they are living in an apartment, they likely don\'t have a lot of disposable
income, as well. (Here, most dwelling units are single family, detached homes.
*Students* live in dorms/appartments -- some 50K at the local university)

Most of my \"artist\" (fine arts) friends rent \"studio space\" for their work.
This amusing as most of them couldn\'t survive on their commissions, let alone
pay for a space to do the work! So, it\'s treated as a hobby and the space
rental is just part of the cost of that hobby. (most are very affluent
so the \"hobby\" is just something to whittle away their waking hours)
Any \"sales\" are mainly to stroke their egos.

If you hobby requires you to have place and be able to make a lot of noise /
dust / <whatever> , the 40 euro / month membership of space is still quite
cheap compared to renting a garage to store your stuff.

2/ The social element.

Especially in spaces who have more a culture of sharing knowledge, having other
people around you who can help you, is always a good thing.

This assumes those people truly are knowledgeable and not just THINKING they
are (or, the most knowledgeable body in the shop).

E.g., when I took the laser cutter course, I asked how to reference the
laser\'s position to the \"origin\" of your CAD document. \"Oh, just manually
slew the laser and press ZERO when you\'re at the right spot on your workpiece!\"
\"And, how do I ensure that my piece is \'square\' with the laser\'s axis?\"
\"Just make sure your ZERO is inside the edges of the piece and it is
approximately square with the edges of the platform!\"

[Really? Is there a MANUAL around here, someplace....? Something
AUTHORITATIVE??]

In certain spaces, giving workshops is just seen as \"a way to make money, so to
keep the space running\".

Yes. Options for income streams -- other than dues -- are limited. The local
shop is constantly applying for grants to offer classes at the local library
branches (i.e., trying to peddle \"know-how\", not access to kit). Or,
partnering with other local \"clubs\" that can effectively sublet parts
of their space, periodically.

But, none of these are long term income streams with any sort of guaranteed
availability. Your rent, OTOH, will be expected EVERY month! Any surplus
you may accumulate can vanish if the HVAC, dust extraction, any tool, etc.
suffers a breakdown that requires purchasing spare parts (if it\'s just
\"labor\", you can hope that some member will step up and take on the task;
this leads to really long repair times as folks usually can\'t drop what they
are doing \"in real life\" just to donate some time to tackle a problem).

I think one of the problems with the local space\'s income stream is they
aren\'t aggressively putting themselves in front of the public. They have
(had?) a TV commercial that would air in teh wee hours of the morning
(likely because the time was donated *or* cheaper to buy). The spot
was shot and chaotic -- lots of 1 second shots of various pieces of equipment
and people while the narrator seemed to be attempting the World\'s Fastest
Speaker award. You were left wondering \"What the hell was THAT all about??\"

Again, you have people that THINK they know how to market the organization
instead of (hiring) professionals who would do so more effectively.

But, professionals cost money!

In other space, giving a workshop is more about \"some people getting together
to try out something together\".

Here, that only seems to be the case for activities that are related to
the space itself. E.g., getting a group together to replace the sacrificial
flooring or move some piece of equipment. Most of the projects that I\'ve
seen are solo efforts -- save for those things done by OTHER groups that
sublet space (like the local robotics team)

So it all differs from space to space.

A couple of years ago, I was talking to somebody why they had a 3D printer in
their hackerspace. (that was when a 3D printer was still 800 euro or so).

He said \"in a hackerspace, we have a 3D printer for two reasons: to allow
people to learn about 3D printing and 3D design, and to print out a few small
object if needed..

But if you do a project where you need -say- 40 pieces of the same thing, don\'t
do it here. Go to a fablab\".

I find this a good example of the different types of spaces, the different
reasons why they exist and, hence, the different reasons why people join them.