Simple audio amp design...

[Cursitor Doom]

On 22/12/2021 08:16, Jan Panteltje wrote:

But to have some transistors to be ably to send an SOS in case you ran out of solder, why not
Point is I have done all that transistors design for all sort of things, and tubes too before that,
And fixed thousands of circuits, some simple, some very complicated, in broadcasting
and in my repair shop.
I can tell you that (having to look) looking at so many different circuits from so many designers
is a great learning experience.

For you that may well be the case. You are obviously infinitely better
at electronics than I will ever be. I know what I\'m good at by this
stage of my life and electronics doesn\'t come close, I\'m afraid. It can
never be anything more than a fascinating hobby for me. What never
ceases to amaze me is how we each have different strengths and
weaknesses in different subjects. People like yourself and John Larkin
and Win Hill and our dearly departed (and much missed) Jim Thompson are
at the top of the tree whereas I\'m barely above root level. So it was
fortuitous that I never went into electronics as a career or I\'d have
been a no-mark and still struggling whereas by choosing something I was
far better suited to I was able to retire in my mid-40s. That at least
was one of my better decisions! :-D
Now I\'m going to have a crack at doing the audio amp for myself. It\'s
well within my ability after all, despite what I\'ve said about myself
above!

In my opinion coming out of some EE school and just connecting IC_type1 to I_type2 is a different art perhaps.
It is what it does and how it works that counts,
It would take many years and hands on experience to get to know that,

All electronics designs, be it a simple audio amp or switcher etc. are interesting, there is a lot you can learn
or should have learned ;-)

Too true!

At least it is on topic, unlike what the slow man just started,

Sadly it\'s been many years indeed since old Bill ever posted anything
relevant or useful to anyone here. Whatever he has to say is best
ignored IMV.

Thanks again for your very welcome assistance, Jan; it\'s always appreciated.

CD.

 

[Cursitor Doom]

On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
<spamjunk@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.

My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.

 

[Tom Gardner]

On 23/12/21 19:03, Cursitor Doom wrote:

On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spamjunk@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.

The vacuum would be the interesting part of that.

I have a couple of Boy Electrician books with similar things.
They also have sections on fun things you can do with your
X-ray machine. They do presume you buy the tube, though, and
warn you to stop if your skin starts becoming red.

I also have a book on how to make soap, and a Scientific
American Cyclopedia (sic) of Formulas (sic). Everything
from beverages to insecticides and a couple of dozen types
of solder.

I\'m well set pour \"après le déluge\".

My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.

Unfortunately life is too short to /do/ everything. We are
lucky we have options.

 

[John Walliker]

On Thursday, 23 December 2021 at 19:58:47 UTC, Tom Gardner wrote:

On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.
The vacuum would be the interesting part of that.

I have a couple of Boy Electrician books with similar things.
They also have sections on fun things you can do with your
X-ray machine. They do presume you buy the tube, though, and
warn you to stop if your skin starts becoming red.

I also have a book on how to make soap, and a Scientific
American Cyclopedia (sic) of Formulas (sic). Everything
from beverages to insecticides and a couple of dozen types
of solder.

I\'m well set pour \"après le déluge\".
My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.
Unfortunately life is too short to /do/ everything. We are
lucky we have options.

Electronics is an incredibly broad field. The skills needed for high
reliability design are very different to those needed to design
low-cost products that are going to be commercially successful
in high volume manufacture. Sometimes joining a collection of
ICs together is the right thing to do. Other times, discrete design
is more appropriate. There is a similar kind of tension between
what should be implemented in hardware and what should be in
software. Should the design be as good as it possibly can be or
should it be \"good enough\"? Generally, there is no one right answer,
but a continuum where different tradeoffs are balanced against
each other.
Just understanding those tradeoffs is in itself a valuable skill.
So there is lots of room for different opinions. While their
proponents often clash it doesn\'t mean that opposing views
are wrong, just different and worth listening to as there may
be insights to an open mind. I have learned a lot here.

John

 

[Three Jeeps]

On Thursday, December 23, 2021 at 2:03:19 PM UTC-5, Cursitor Doom wrote:

On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.
Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.
My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.
I\'m really into that kind of thing. In theory at any rate.

i\'ve built my own vacuum tube as an experiment long time ago. I even had (still have?) ideas about starting my own tube fab facility for audio amps. Alas, the tricks of the trade are probably too far buried in the past and the learning curve would be steep. I\'ve read a number of papers from sylvania and rca engineers about some of their discoveries regarding material properties and their effects on tube performance. All of this would have to be \'relearned\'.
In any event, here is a video that I like a lot. It is helpful to have some of the equipment that he does, to build a tube: tack welder, vacuum pump, glass tube lathe, glass furnace, etc. it appears that even his electronic test gear is handmade. A real craftsman....
https://www.youtube.com/watch?v=EzyXMEpq4qw
enjoy
j

 

[Jan Panteltje]

On a sunny day (Thu, 23 Dec 2021 19:03:13 +0000) it happened Cursitor Doom
<cd@notformail.com> wrote in <rph9sg52tnokc48s7ab241588s9ibaemen@4ax.com>:

On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spamjunk@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.

My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.

LOL as a kid I build a spark bridge transmitter from an ignition coil
I asked a guy at school who\'s father was a radioham if he could ask his
father if he could receive it (a few miles from where I lived).
Man was he angry! So it worked!

 

[Tabby]

On Sunday, 19 December 2021 at 12:40:23 UTC, Cursitor Doom wrote:

Greetings, gentlemen,

I have a vintage MW/LW/SW 12V battery-powered radio I picked up recently
at a yard sale. Being 50 years old, however, it has a few faults and
needs realignment and whatnot. Before I can proceed with that, I\'ve
discovered that the transistors it uses (mostly obsolete germanium
devices) suffer from tin whiskers so I will need to re-jig the board so
they can be replaced with silicon ones instead. The design is very

No no no no no. Use new russian germanium trs where needed. See some of shango066 tr radio repair vids, some concentrate on tr replacement.

Whiskers can also be burnt away with a battery, but they do regrow.

 

[Jan Panteltje]

On a sunny day (Fri, 24 Dec 2021 00:33:04 -0800 (PST)) it happened Tabby
<tabbypurr@gmail.com> wrote in
<db5a17ff-b81e-42fb-83ec-31a69c21e6a0n@googlegroups.com>:

On Thursday, 23 December 2021 at 19:58:47 UTC, Tom Gardner wrote:
On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.
The vacuum would be the interesting part of that.

It turns out you don\'t need a vacuum to get a thermionic valve to work.
https://odysee.com/@doctorvolt:a/can-we-build-a-tube-amplifier-with-light:1

Interesting, nice video.

 

[server]

On Thu, 23 Dec 2021 19:58:41 +0000, Tom Gardner
<spamjunk@blueyonder.co.uk> wrote:

On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spamjunk@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.

The vacuum would be the interesting part of that.

Most tubes used a mechanical vacuum pump and then a getter to clean
up. Big beautiful transmitting tubes and PMTs and other high-quality
tubes mostly weren\'t gettered, probably baked and pumped hard.

I have a couple of Boy Electrician books with similar things.
They also have sections on fun things you can do with your
X-ray machine. They do presume you buy the tube, though, and
warn you to stop if your skin starts becoming red.

I had The Boy Scientist when I was a kid. Tons of dangerous stuff. I
wonder if I can find a copy somewhere.

I also have a book on how to make soap, and a Scientific
American Cyclopedia (sic) of Formulas (sic). Everything
from beverages to insecticides and a couple of dozen types
of solder.

I\'m well set pour \"après le déluge\".


My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.

Unfortunately life is too short to /do/ everything. We are
lucky we have options.

Yeah. I would have made a terrible peasant farmer.




--

I yam what I yam - Popeye

 

[Cursitor Doom]

On Fri, 24 Dec 2021 00:35:36 -0800 (PST), Tabby <tabbypurr@gmail.com>
wrote:

On Sunday, 19 December 2021 at 12:40:23 UTC, Cursitor Doom wrote:
Greetings, gentlemen,

I have a vintage MW/LW/SW 12V battery-powered radio I picked up recently
at a yard sale. Being 50 years old, however, it has a few faults and
needs realignment and whatnot. Before I can proceed with that, I\'ve
discovered that the transistors it uses (mostly obsolete germanium
devices) suffer from tin whiskers so I will need to re-jig the board so
they can be replaced with silicon ones instead. The design is very

No no no no no. Use new russian germanium trs where needed. See some of shango066 tr radio repair vids, some concentrate on tr replacement.

Whiskers can also be burnt away with a battery, but they do regrow.

Cheers, Tabbs. I\'d forgotten about the Russian option!

 

[Phil Allison]

jla...@highlandsniptechnology.com wrote:
==============================

The vacuum would be the interesting part of that.

Most tubes used a mechanical vacuum pump and then a getter to clean
up.

** The \"getter\" acts throughout the life of the tube.

Big beautiful transmitting tubes and PMTs and other high-quality
tubes mostly weren\'t gettered, probably baked and pumped hard.

** They all have some form of \" getter \" -
just not the common \"flashed\" kind that deposits metallic Barium on the inside of the glass.

Turns white & powdery if air gets in, and vanishes if the tube seriously over heats.



....... Phil

 

[Phil Allison]

Tabby wrote:
==============

The vacuum would be the interesting part of that.

It turns out you don\'t need a vacuum to get a thermionic valve to work.

https://odysee.com/@doctorvolt:a/can-we-build-a-tube-amplifier-with-light:1

** The vid does not say the was no vacuum.

Common light bulbs contain low pressure nitrogen but some small types have
a vacuum inside.

IME regular electron tubes ( triodes / pentodes) fail to operate immediately
when air leaks in.


...... Phil

 

[Wim Ton]

On Friday, 24 December 2021 at 15:18:14 UTC+1, jla...@highlandsniptechnology.com wrote:

On Thu, 23 Dec 2021 19:58:41 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.

The vacuum would be the interesting part of that.
Most tubes used a mechanical vacuum pump and then a getter to clean
up. Big beautiful transmitting tubes and PMTs and other high-quality
tubes mostly weren\'t gettered, probably baked and pumped hard.

I have a couple of Boy Electrician books with similar things.
They also have sections on fun things you can do with your
X-ray machine. They do presume you buy the tube, though, and
warn you to stop if your skin starts becoming red.
I had The Boy Scientist when I was a kid. Tons of dangerous stuff. I
wonder if I can find a copy somewhere.

I also have a book on how to make soap, and a Scientific
American Cyclopedia (sic) of Formulas (sic). Everything
from beverages to insecticides and a couple of dozen types
of solder.

I\'m well set pour \"après le déluge\".


My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.

Unfortunately life is too short to /do/ everything. We are
lucky we have options.
Yeah. I would have made a terrible peasant farmer.




--

I yam what I yam - Popeye

To see what it takes to really make things from scratch see: \"The toaster project\".
Most \"make things from scratch\" ideas require for example blast furnaces with their supply chain to provide high quality steel, etc.
Even HD Thoreau uses a second-hand building for his Walden project.
Wim

 

[server]

On Sat, 25 Dec 2021 00:29:44 -0800 (PST), Wim Ton <wim.ton@gmail.com>
wrote:

On Friday, 24 December 2021 at 15:18:14 UTC+1, jla...@highlandsniptechnology.com wrote:
On Thu, 23 Dec 2021 19:58:41 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.

The vacuum would be the interesting part of that.
Most tubes used a mechanical vacuum pump and then a getter to clean
up. Big beautiful transmitting tubes and PMTs and other high-quality
tubes mostly weren\'t gettered, probably baked and pumped hard.

I have a couple of Boy Electrician books with similar things.
They also have sections on fun things you can do with your
X-ray machine. They do presume you buy the tube, though, and
warn you to stop if your skin starts becoming red.
I had The Boy Scientist when I was a kid. Tons of dangerous stuff. I
wonder if I can find a copy somewhere.

I also have a book on how to make soap, and a Scientific
American Cyclopedia (sic) of Formulas (sic). Everything
from beverages to insecticides and a couple of dozen types
of solder.

I\'m well set pour \"après le déluge\".


My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.

Unfortunately life is too short to /do/ everything. We are
lucky we have options.
Yeah. I would have made a terrible peasant farmer.




--

I yam what I yam - Popeye
To see what it takes to really make things from scratch see: \"The toaster project\".
Most \"make things from scratch\" ideas require for example blast furnaces with their supply chain to provide high quality steel, etc.
Even HD Thoreau uses a second-hand building for his Walden project.
Wim

The idea of a settlement surving on Mars is absurd. There are no
WalMarts, no Home Depots, no pizza joints, no trees for firewood.
Nothing to eat or breathe.

Our civilization grew very slowly at first. You need a lathe to make a
lathe.



--

I yam what I yam - Popeye

 

[Anthony William Sloman]

On Sunday, December 26, 2021 at 1:17:33 AM UTC+11, jla...@highlandsniptechnology.com wrote:

On Sat, 25 Dec 2021 00:29:44 -0800 (PST), Wim Ton <wim...@gmail.com
wrote:
On Friday, 24 December 2021 at 15:18:14 UTC+1, jla...@highlandsniptechnology.com wrote:
On Thu, 23 Dec 2021 19:58:41 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

Our civilization grew very slowly at first. You need a lathe to make a lathe.

You can use a lathe to make a lathe. Obviously. the first lathe wasn\'t made that way.

<https://www.gracesguide.co.uk/Vaucanson%27s_Lathe>

Vaucanson did a lot of work on making more nearly perfect lead-screws, essentially by working in a way that let the turn-to-turn imperfections in existing lead screws average out over a large number of number of turns. It does seem to have been tedious and time-consuming work.

If somebody had invented a laser interferometer early on, the job would have been much easier. Newton\'s rings predate Vaucanson\'s lathe, and the sodium D-line has a pretty narrow spectrum, but it would be hard to make an interferometer without a lathe.

--
Bill Sloman, Sydney

 

[Lasse Langwadt Christensen]

lørdag den 25. december 2021 kl. 15.17.33 UTC+1 skrev jla...@highlandsniptechnology.com:

On Sat, 25 Dec 2021 00:29:44 -0800 (PST), Wim Ton <wim...@gmail.com
wrote:
On Friday, 24 December 2021 at 15:18:14 UTC+1, jla...@highlandsniptechnology.com wrote:
On Thu, 23 Dec 2021 19:58:41 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.

The vacuum would be the interesting part of that.
Most tubes used a mechanical vacuum pump and then a getter to clean
up. Big beautiful transmitting tubes and PMTs and other high-quality
tubes mostly weren\'t gettered, probably baked and pumped hard.

I have a couple of Boy Electrician books with similar things.
They also have sections on fun things you can do with your
X-ray machine. They do presume you buy the tube, though, and
warn you to stop if your skin starts becoming red.
I had The Boy Scientist when I was a kid. Tons of dangerous stuff. I
wonder if I can find a copy somewhere.

I also have a book on how to make soap, and a Scientific
American Cyclopedia (sic) of Formulas (sic). Everything
from beverages to insecticides and a couple of dozen types
of solder.

I\'m well set pour \"après le déluge\".


My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.

Unfortunately life is too short to /do/ everything. We are
lucky we have options.
Yeah. I would have made a terrible peasant farmer.




--

I yam what I yam - Popeye
To see what it takes to really make things from scratch see: \"The toaster project\".
Most \"make things from scratch\" ideas require for example blast furnaces with their supply chain to provide high quality steel, etc.
Even HD Thoreau uses a second-hand building for his Walden project.
Wim
The idea of a settlement surving on Mars is absurd. There are no
WalMarts, no Home Depots, no pizza joints, no trees for firewood.
Nothing to eat or breathe.

Our civilization grew very slowly at first. You need a lathe to make a
lathe.

https://youtu.be/XCt3LooUVsQ

 

[Cursitor Doom]

On Sun, 26 Dec 2021 06:27:17 -0800 (PST), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

lørdag den 25. december 2021 kl. 15.17.33 UTC+1 skrev jla...@highlandsniptechnology.com:
On Sat, 25 Dec 2021 00:29:44 -0800 (PST), Wim Ton <wim...@gmail.com
wrote:
On Friday, 24 December 2021 at 15:18:14 UTC+1, jla...@highlandsniptechnology.com wrote:
On Thu, 23 Dec 2021 19:58:41 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.

The vacuum would be the interesting part of that.
Most tubes used a mechanical vacuum pump and then a getter to clean
up. Big beautiful transmitting tubes and PMTs and other high-quality
tubes mostly weren\'t gettered, probably baked and pumped hard.

I have a couple of Boy Electrician books with similar things.
They also have sections on fun things you can do with your
X-ray machine. They do presume you buy the tube, though, and
warn you to stop if your skin starts becoming red.
I had The Boy Scientist when I was a kid. Tons of dangerous stuff. I
wonder if I can find a copy somewhere.

I also have a book on how to make soap, and a Scientific
American Cyclopedia (sic) of Formulas (sic). Everything
from beverages to insecticides and a couple of dozen types
of solder.

I\'m well set pour \"après le déluge\".


My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.

Unfortunately life is too short to /do/ everything. We are
lucky we have options.
Yeah. I would have made a terrible peasant farmer.




--

I yam what I yam - Popeye
To see what it takes to really make things from scratch see: \"The toaster project\".
Most \"make things from scratch\" ideas require for example blast furnaces with their supply chain to provide high quality steel, etc.
Even HD Thoreau uses a second-hand building for his Walden project.
Wim
The idea of a settlement surving on Mars is absurd. There are no
WalMarts, no Home Depots, no pizza joints, no trees for firewood.
Nothing to eat or breathe.

Our civilization grew very slowly at first. You need a lathe to make a
lathe.

https://youtu.be/XCt3LooUVsQ

You need a lathe to make a lathe, but that\'s not *all* you need. The
guy in the video uses wood to get around this problem, but if you wish
to make a serious metal turning lathe, you will need some means of
producing castings for the turned components such as shafts and
bearings to be stably held. And for screw cutting, you then need some
way of making gears as well. You can\'t make a practical
metal-turning/screw-cutting lathe without castings, a mill and various
cutting bits additionally. And the cutters require a grinder to put an
edge on \'em. It\'s therefore not as simple as Bill Sloman
suggested^h^h^h^h^h^h^h^h^h^h.
;->

 

[Anthony William Sloman]

On Monday, December 27, 2021 at 11:22:07 AM UTC+11, Cursitor Doom wrote:

On Sun, 26 Dec 2021 06:27:17 -0800 (PST), Lasse Langwadt Christensen <lang...@fonz.dk> wrote:
lørdag den 25. december 2021 kl. 15.17.33 UTC+1 skrev jla...@highlandsniptechnology.com:
On Sat, 25 Dec 2021 00:29:44 -0800 (PST), Wim Ton <wim...@gmail.com> wrote:
On Friday, 24 December 2021 at 15:18:14 UTC+1, jla...@highlandsniptechnology.com wrote:
On Thu, 23 Dec 2021 19:58:41 +0000, Tom Gardner <spam...@blueyonder..co.uk> wrote:
On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner <spam...@blueyonder.co.uk> wrote:

Our civilization grew very slowly at first. You need a lathe to make a
lathe.

https://youtu.be/XCt3LooUVsQ

You need a lathe to make a lathe, but that\'s not *all* you need.

You clearly don\'t need a lathe to make a lathe. Like everything else that has evolved, we got closer to modern lathe by slow degrees.

The guy in the video uses wood to get around this problem, but if you wish
to make a serious metal turning lathe, you will need some means of
producing castings for the turned components such as shafts and
bearings to be stably held. And for screw cutting, you then need some
way of making gears as well. You can\'t make a practical
metal-turning/screw-cutting lathe without castings, a mill and various
cutting bits additionally. And the cutters require a grinder to put an
edge on \'em.
It\'s therefore not as simple as Bill Sloman suggested^h^h^h^h^h^h^h^h^h^h.

It\'s not as simple as Cursitor Doom thought I was suggesting - he is remarkably dim.

<https://www.gracesguide.co.uk/Vaucanson%27s_Lathe>

Vaucanson\'s lathe is one of many relatively small steps that got us the metal-working lathes we have now. Castings are a lot older that that, and there\'s a Greek astronomical calculating machine that got fished out of the Mediterranean after a couple of thousand years immersion that included meshng toothed wheels - which is to say - gears.

https://en.wikipedia.org/wiki/Antikythera_mechanism

--
Bill Sloman, Sydney

 

[whit3rd]

On Sunday, December 26, 2021 at 6:55:15 PM UTC-8, bill....@ieee.org wrote:

On Monday, December 27, 2021 at 11:22:07 AM UTC+11, Cursitor Doom wrote:

You need a lathe to make a lathe, but that\'s not *all* you need.

You clearly don\'t need a lathe to make a lathe. Like everything else that has evolved, we got closer to modern lathe by slow degrees.

The simplest lathe is the portable bodger\'s device; just a couple of pointy
steel bits that can be fixed to a timber. Poke one point into end A of the
workpiece, the other point into end B, and wrap a cord around the workpiece.
Reciprocating mechanism (pedals, springs, counterweights, or somesuch)
turns the work.

A traditional bodger would disappear into a wood with a few bits of steel, and
come back at the end of the day with a few bits of steel and a packload of
chair spindles, or table legs, or spokes...having cut trees and processed the wood.

A grain mill (water powered) could be built from wood and stone, of course. And until steam
and electricity got convenient, iron mills were all on watercourses too. They made
iron bars, and any smithy could turn those into pointy bits, thus making a lathe
with hammers and tongs.

 

[server]

On Mon, 27 Dec 2021 00:22:00 +0000, Cursitor Doom <cd@nospam.com>
wrote:

On Sun, 26 Dec 2021 06:27:17 -0800 (PST), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:

lørdag den 25. december 2021 kl. 15.17.33 UTC+1 skrev jla...@highlandsniptechnology.com:
On Sat, 25 Dec 2021 00:29:44 -0800 (PST), Wim Ton <wim...@gmail.com
wrote:
On Friday, 24 December 2021 at 15:18:14 UTC+1, jla...@highlandsniptechnology.com wrote:
On Thu, 23 Dec 2021 19:58:41 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

On 23/12/21 19:03, Cursitor Doom wrote:
On Wed, 22 Dec 2021 13:36:14 +0000, Tom Gardner
spam...@blueyonder.co.uk> wrote:

While I have some sympathy for the sentiment, I don\'t agree
with the reasoning and conclusion. OTOH if it is solely for
your sense of achievement, then that\'s a justifiable reason.

But why stop at discrete semiconductors? Why not go a little
further and make your own inductors, capacitors and valves.

Yes, why not? I recall there\'s an old book called something like
\'desert island radio\' which explains how to build a working comms
radio solely from stuff you\'d find washed up on a beach - including
valves. Fascinating.

The vacuum would be the interesting part of that.
Most tubes used a mechanical vacuum pump and then a getter to clean
up. Big beautiful transmitting tubes and PMTs and other high-quality
tubes mostly weren\'t gettered, probably baked and pumped hard.

I have a couple of Boy Electrician books with similar things.
They also have sections on fun things you can do with your
X-ray machine. They do presume you buy the tube, though, and
warn you to stop if your skin starts becoming red.
I had The Boy Scientist when I was a kid. Tons of dangerous stuff. I
wonder if I can find a copy somewhere.

I also have a book on how to make soap, and a Scientific
American Cyclopedia (sic) of Formulas (sic). Everything
from beverages to insecticides and a couple of dozen types
of solder.

I\'m well set pour \"après le déluge\".


My father has a book describing how to make your own
car - starting with how to make the tools necessary to make
the car.

I\'m really into that kind of thing. In theory at any rate.

Unfortunately life is too short to /do/ everything. We are
lucky we have options.
Yeah. I would have made a terrible peasant farmer.




--

I yam what I yam - Popeye
To see what it takes to really make things from scratch see: \"The toaster project\".
Most \"make things from scratch\" ideas require for example blast furnaces with their supply chain to provide high quality steel, etc.
Even HD Thoreau uses a second-hand building for his Walden project.
Wim
The idea of a settlement surving on Mars is absurd. There are no
WalMarts, no Home Depots, no pizza joints, no trees for firewood.
Nothing to eat or breathe.

Our civilization grew very slowly at first. You need a lathe to make a
lathe.

https://youtu.be/XCt3LooUVsQ

You need a lathe to make a lathe, but that\'s not *all* you need. The
guy in the video uses wood to get around this problem, but if you wish
to make a serious metal turning lathe, you will need some means of
producing castings for the turned components such as shafts and
bearings to be stably held. And for screw cutting, you then need some
way of making gears as well. You can\'t make a practical
metal-turning/screw-cutting lathe without castings, a mill and various
cutting bits additionally. And the cutters require a grinder to put an
edge on \'em. It\'s therefore not as simple as Bill Sloman
suggested^h^h^h^h^h^h^h^h^h^h.
;-

Not to mention the electric motor, the pulleys, the belts, and the
electric power plant out there somewhere, some of which required
lathes to build.



--

I yam what I yam - Popeye