Then and now

[gareth]

Nowadays, to manufacture an HF RX, with all the concomitant
high density ICs that are around, the biggest design chore
is to cut out the opening for the LCD display on the front
panel.

But, looking in detail at this EA12, almost every facet of
it has involved intricate design and manufacture if only the
mechanical components are considered, and all this from the
days of pencils and drawing boards, long before the era
of computer aiding.

Firstly, there is the aliminium casting for the front panel, and
secondly is the rotary arm coupling to the tuning condenser
to linearise the frequency coverage, amongst many other mechanical
achievements.

Clearly the Stratton people knew their onions when it came
to designing and producing radios.

My gast has never been so flabbered; no wonder it had taken me
so long as a tyro machinist to not (yet) succeed in my own efforts!

[Lostgallifreyan]

Post by gareth
Firstly, there is the aliminium casting for the front panel, and
secondly is the rotary arm coupling to the tuning condenser
to linearise the frequency coverage, amongst many other mechanical
achievements.
Clearly the Stratton people knew their onions when it came
to designing and producing radios.

I limit my CAD for mechanics to an early version of SketchUp, the main
advantage beign an ability to make clean lines, erase faults as if they'd
never been, try new ideas and revert painlessly, and to turn the model in
three dimensions. In the past, the fact that makers likely had to do design
and also handle real parts they made, meant the brain fed back detail that
kept their vision clear. Even so it is admirable.

On the other hand (not radio related, exactly), I have built from expired
patent and base principle (I find other's code utterly impenetrable so have
not plundered any), an entire polyphonic, multitimbral FM (actually, phase
mod) synthesiser, with a few tricks that not even Yamaha managed.

In short, while it is amazing what people in the past acheived, it is also
true that in 1980, to do what I can do alone, it took a university professors
(John Chowning) and a large multinational company (Yamaha), and 10 years of
research and development to do! It's still taking me a few years, but it is
at least possible, and not so long ago it was beyond any practical dreaming.

There is real art in old radio parts though, especially the tuning
capacitors, and those old hybrid canned parts with chokes and caps and such,
especially in the context of a small forest of valves.... The intricacies of
my PhaseMod synth, while fun and no ends of cool, are hard to sell to a
public who woudl see even LESS of that wonder than they do when confronted
with an actual hardware dedicated IC. :) But such is the price we pay for the
power....

[Chronos]

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Cancel-Lock: sha1:XtSDy5g3yXa0V1xb5xhEQYpgL7Y=
Bytes: 2025
Xref: number.nntp.dca.giganews.com rec.radio.amateur.boatanchors:139481 rec.radio.amateur.homebrew:118768 uk.radio.amateur:790116

On Wed, 20 Aug 2014 11:38:57 +0100

Post by gareth
Nowadays, to manufacture an HF RX, with all the concomitant
high density ICs that are around, the biggest design chore
is to cut out the opening for the LCD display on the front
panel.

I have to say that anyone who can make a decent looking front panel has
my admiration. My attempts at chassis bashing have always looked like
something salvaged from a rather nasty car accident. The Dremel doesn't
help - it just makes making a mess faster ;-)

[gareth]

Post by Chronos
On Wed, 20 Aug 2014 11:38:57 +0100

Post by gareth
Nowadays, to manufacture an HF RX, with all the concomitant
high density ICs that are around, the biggest design chore
is to cut out the opening for the LCD display on the front
panel.

I have to say that anyone who can make a decent looking front panel has
my admiration. My attempts at chassis bashing have always looked like
something salvaged from a rather nasty car accident. The Dremel doesn't
help - it just makes making a mess faster ;-)

Always used to be a problem until I clamped down the workpiece in a drill
press and stopped trying to do everything freehand. Also, the old adage of
measure
twice and cut but once helps!

Being impatient myself, I did make a "PCB" by grinding out the lands using a
Dremel-equivalent
miniature grinding wheel, but where I transgressed with that was to grind
each land as I needed it,
after soldering in the previous component, with the result that the board
slowly curved.

[Michael Black]

Post by Chronos
On Wed, 20 Aug 2014 11:38:57 +0100

Post by gareth
Nowadays, to manufacture an HF RX, with all the concomitant
high density ICs that are around, the biggest design chore
is to cut out the opening for the LCD display on the front
panel.

I have to say that anyone who can make a decent looking front panel has
my admiration. My attempts at chassis bashing have always looked like
something salvaged from a rather nasty car accident. The Dremel doesn't
help - it just makes making a mess faster ;-)

That's why they created bezels, to cover up what lies behind.

Michael

[Lostgallifreyan]

Post by Chronos
The Dremel doesn't
help - it just makes making a mess faster ;-)

As I found too, once. Try Proxxon instead. Works for me...

[Scott Dorsey]

Post by Chronos
On Wed, 20 Aug 2014 11:38:57 +0100

Post by gareth
Nowadays, to manufacture an HF RX, with all the concomitant
high density ICs that are around, the biggest design chore
is to cut out the opening for the LCD display on the front
panel.

I have to say that anyone who can make a decent looking front panel has
my admiration. My attempts at chassis bashing have always looked like
something salvaged from a rather nasty car accident. The Dremel doesn't
help - it just makes making a mess faster ;-)

http://www.frontpanelexpress.com

Now, they don't do any fancy 3-D work, so if you are of a mind to have
heatsinks in the panel or fancy bezels around your slide rule display
along with the mounts for the pulleys built into the front panel, you
will be out of luck.

But if you don't mind machining the pulley mounts separately and having
a second metal plate with the scale bolted on standoffs to get your
frequency display for the tuning, it can work out nicely.
--scott

[Paul]

Post by Chronos
On Wed, 20 Aug 2014 11:38:57 +0100

Post by gareth
Nowadays, to manufacture an HF RX, with all the concomitant
high density ICs that are around, the biggest design chore
is to cut out the opening for the LCD display on the front
panel.

I have to say that anyone who can make a decent looking front panel has
my admiration. My attempts at chassis bashing have always looked like
something salvaged from a rather nasty car accident. The Dremel doesn't
help - it just makes making a mess faster ;-)

The tradition here, used to be nibbling tool + Hammond Box.

Loading Image...

http://www.ebay.com/itm/Deluxe-Nibbling-Tool-for-electronic-chassis-making-/160459856656

http://angela.com/hammondaluminum17x10x2chassis1444-30.aspx

Loading Image...

You drill a hole big enough to take the cutting head of the nibbler.
Then, like a jig saw, the nibbler cuts an arbitrary pattern in
the aluminum sheet. You can do square or round holes. The square
holes will be high quality (requires a steady hand, don't
rush it). The round holes need touch up with a round file
(depending on your level of patience, and availability of a bezel
to cover the mess).

The advert lists a few different materials it works in, but
let's be honest - it's only for aluminum, and only of a
limited thickness. If you have to fight with the tool,
you won't get nice looking results.

In this picture, you can see the nibbling tool has just cut an "L"
on its way to finishing a big square. While the person here drilled
four pilot holes for the nibbler (to do the square), only one is
really needed. You can do the entire square, racetrack style.
You could even drill a pilot in the middle of the square, and
"drive" to the edges to cut the square.

Loading Image...

http://www.diyaudio.com/forums/tubes-valves/181748-tony-builds-7n7-preamp.html

That project cheated by using other tools to do the round holes.
The round holes are too high quality for the nibbler. But lacking
such tools, I wouldn't mind faking the round holes with the nibbler.
I could never afford a whole kit of tool n' die hole cutters
(the kind you work by compression with a wrench). One of the tools
in this promotional picture (mid-left), is a proper hole cutter.

http://angela.com/images/products/detail/HammondAluminumChassis.15.jpg

Paul

[highlandham]

Post by Paul

Post by Chronos
On Wed, 20 Aug 2014 11:38:57 +0100

Post by gareth
Nowadays, to manufacture an HF RX, with all the concomitant
high density ICs that are around, the biggest design chore
is to cut out the opening for the LCD display on the front
panel.

I have to say that anyone who can make a decent looking front panel has
my admiration. My attempts at chassis bashing have always looked like
something salvaged from a rather nasty car accident. The Dremel doesn't
help - it just makes making a mess faster ;-)

The tradition here, used to be nibbling tool + Hammond Box.
http://www.mpja.com/images/31197-large.jpg
http://www.ebay.com/itm/Deluxe-Nibbling-Tool-for-electronic-chassis-making-/160459856656
http://angela.com/hammondaluminum17x10x2chassis1444-30.aspx
http://angela.com/images/products/detail/HammondAluminumChassis.15.jpg
You drill a hole big enough to take the cutting head of the nibbler.
Then, like a jig saw, the nibbler cuts an arbitrary pattern in
the aluminum sheet. You can do square or round holes. The square
holes will be high quality (requires a steady hand, don't
rush it). The round holes need touch up with a round file
(depending on your level of patience, and availability of a bezel
to cover the mess).
The advert lists a few different materials it works in, but
let's be honest - it's only for aluminum, and only of a
limited thickness. If you have to fight with the tool,
you won't get nice looking results.
In this picture, you can see the nibbling tool has just cut an "L"
on its way to finishing a big square. While the person here drilled
four pilot holes for the nibbler (to do the square), only one is
really needed. You can do the entire square, racetrack style.
You could even drill a pilot in the middle of the square, and
"drive" to the edges to cut the square.
http://i5.photobucket.com/albums/y155/leoman53/IMG_1326.jpg
http://www.diyaudio.com/forums/tubes-valves/181748-tony-builds-7n7-preamp.html
That project cheated by using other tools to do the round holes.
The round holes are too high quality for the nibbler. But lacking
such tools, I wouldn't mind faking the round holes with the nibbler.
I could never afford a whole kit of tool n' die hole cutters
(the kind you work by compression with a wrench). One of the tools
in this promotional picture (mid-left), is a proper hole cutter.
http://angela.com/images/products/detail/HammondAluminumChassis.15.jpg
Paul

Nibbling tools are still available from Radio Shack (in USA) for US$9.99

Frank GM0CSZ / KN6WH

[Scott Dorsey]

Post by highlandham
Nibbling tools are still available from Radio Shack (in USA) for US$9.99

Don't do it! Spend a little more and get a good one from MSC or somebody.
--scott

[Michael Black]

Post by Scott Dorsey

Post by highlandham
Nibbling tools are still available from Radio Shack (in USA) for US$9.99

Don't do it! Spend a little more and get a good one from MSC or somebody.
--scott

My nibbler is from Radio Shack, about 30 years old, maybe 35. I couldn't
tell any real difference from an Adel nibbler, which I had borrowed and
used before I got my own.

Michael

[Lordgnome]

Post by Chronos
On Wed, 20 Aug 2014 11:38:57 +0100

Post by gareth
Nowadays, to manufacture an HF RX, with all the concomitant
high density ICs that are around, the biggest design chore
is to cut out the opening for the LCD display on the front
panel.

I have to say that anyone who can make a decent looking front panel has
my admiration. My attempts at chassis bashing have always looked like
something salvaged from a rather nasty car accident. The Dremel doesn't
help - it just makes making a mess faster ;-)

Someone once said to me, that precision engineering was the easiest
thing in the world - far easier than having to 'adjust' holes to fit
things and used a lot less material!
I freely admit that my earlier work was not something to be proud of.

Les.

[gareth]

Post by Lordgnome
Someone once said to me, that precision engineering was the easiest
thing in the world - far easier than having to 'adjust' holes to fit
things and used a lot less material!
I freely admit that my earlier work was not something to be proud of.

Somewhere on the Net is a poster of silly screws to handle such problems.
along the lines of a screw with a bit shifted sideways!

Anyone got the URL?

[highlandham]

Post by gareth

Post by Lordgnome
Someone once said to me, that precision engineering was the easiest
thing in the world - far easier than having to 'adjust' holes to fit
things and used a lot less material!
I freely admit that my earlier work was not something to be proud of.

Somewhere on the Net is a poster of silly screws to handle such problems.
along the lines of a screw with a bit shifted sideways!
Anyone got the URL?

========================
These screw type punchers were/are available from Radio Spares (RS).
I have a few sizes up to 30 mm diameter.

Frank , GM0CSZ / KN6WH

[Lostgallifreyan]

Post by highlandham

Post by gareth
Somewhere on the Net is a poster of silly screws to handle such problems.
along the lines of a screw with a bit shifted sideways!
Anyone got the URL?

========================
These screw type punchers were/are available from Radio Spares (RS).
I have a few sizes up to 30 mm diameter.

I think he had something far sillier in mind. :) Pythonesque, even. But I
know the puches you mean, I have a couple for 20mm and 16mm, I considered one
for 25 pin D-sub but in the end I never wanted to repeat enough to justify
anything other than finely dotted drill-lines followed by knocking out the
middle bit and light filing to clean up. Those hole puches don't always work
well, especially on thicker panels, or panels that already have a tough
enamel type coating. They're also not cheap, I just kept some for hole sizes
I did need to use a lot.

[Brian Reay]

Post by Lostgallifreyan

Post by highlandham

Post by gareth
Somewhere on the Net is a poster of silly screws to handle such problems.
along the lines of a screw with a bit shifted sideways!
Anyone got the URL?

========================
These screw type punchers were/are available from Radio Spares (RS).
I have a few sizes up to 30 mm diameter.

I think he had something far sillier in mind. :) Pythonesque, even. But I
know the puches you mean, I have a couple for 20mm and 16mm, I considered one
for 25 pin D-sub but in the end I never wanted to repeat enough to justify
anything other than finely dotted drill-lines followed by knocking out the
middle bit and light filing to clean up. Those hole puches don't always work
well, especially on thicker panels, or panels that already have a tough
enamel type coating. They're also not cheap, I just kept some for hole sizes
I did need to use a lot.

They tend to be fine for thin steal (eg car panels if you are fitting an
antenna) or the softer aluminium alloys but can jam on the harder alloys, a
little paraffin usually helps (assuming proper cutting fluid for aluminium
isn't to hand). Given you are using hand tools, flash point shouldn't be an
issue. WD40 also works.

I've had good results with a 'cone drill', provided I used a drill press
and the work piece was firmly clamped to the bed. Of course, using a
suitable cutting fluid always helps.

[gareth]

Post by Brian Reay
They tend to be fine for thin steal (eg car panels if you are fitting an
antenna) or the softer aluminium alloys but can jam on the harder alloys, a
little paraffin usually helps (assuming proper cutting fluid for aluminium
isn't to hand).

Paraffin _IS_ the recommended cutting fluid for aluminium

[Lostgallifreyan]

Post by Brian Reay
They tend to be fine for thin steal (eg car panels if you are fitting an
antenna)

Good point. I don't drive or own any large boatanchors so I'm not used to
thinking of non-portable or unsupported surfaces. It may even be easier to
improvise with a slightly wrong hole punch (or aim small and file
outwards) and some large washers than to attempt the way I usually do things.

For small round holes of unspecified size I have never beaten an M3 pilot
hole followed by a tapered reamer, deburring the result with a Stanley blade.
That is VERY cheap, I started out that way and it was a couple of years
before I needed anything better.

[Brian Reay]

Post by Lostgallifreyan

Post by Brian Reay
They tend to be fine for thin steal (eg car panels if you are fitting an
antenna)

Good point. I don't drive or own any large boatanchors so I'm not used to
thinking of non-portable or unsupported surfaces. It may even be easier to
improvise with a slightly wrong hole punch (or aim small and file
outwards) and some large washers than to attempt the way I usually do things.
For small round holes of unspecified size I have never beaten an M3 pilot
hole followed by a tapered reamer, deburring the result with a Stanley blade.
That is VERY cheap, I started out that way and it was a couple of years
before I needed anything better.

Well, as you probably know, real precision holes (eg in watches) are pilot
drilled and reamed, rather
than drilled to size.

The Stanley blade is not, however, part of the procedure. ;-) A fine
broach would be used I would think.

I've repaired a number of pocket watches and clocks but always by hunting
down new parts if needed, or getting them
made. Sadly, my dexterity isn't up to it these days, although it has been
improving recently- much to my surprise- plus I've learned to use my left
hand more. I may rebuild my modest collection of pocket watches, stolen
some years back. They were all ones I had restored, rather than simply
bought working. It is surprise that, even for quite old movements, you can
still locate new, old stock, parts. I recall a trek to a dusting shop in
Notting Hill for a part for a 1920s gold hunter. The shop owner looked at
the details and the broken part, thought for about 2 mins, turn to an array
of 100s of little draws, and produced one. The price? £1. The watch was
worth many times that. I return to the shop many times, it was always the
same. He always had a queue of others with similar wants. He fail once, a
balance staff for an 1883 cylinder escapement. I had that made, £5, inc.
fitting to the balance. He did have a suitable main spring and crystal
glass.

I expect both watches ended up being sold for scrap gold and silver when
the toe rags fenced them. The culprits were caught but the items were not
recovered.

[Lostgallifreyan]

Post by Brian Reay
Well, as you probably know, real precision holes (eg in watches) are pilot
drilled and reamed, rather
than drilled to size.
The Stanley blade is not, however, part of the procedure. ;-)

Indeed. There are reamers, and there are reamers. Mine is NOT a precision
instrument, but you knwo what they say: Don't fear the Reamer. Awl or
nothing, says I. >:)

[Lostgallifreyan]

Post by Brian Reay
They were all ones I had restored, rather than simply
bought working. It is surprise that, even for quite old movements, you can
still locate new, old stock, parts.

There was a time, very brief, when I was fifteen or so, and had been given a
few old watches and clocks after I'd shown an ability to get small mechanisms
moving after years of reluctance, but I never took it far, I usually ended up
just taking them apart and admiring the extreme balance and precision of the
tiny cogs and escapements, and also the precision and brilliance of the ruby
bearings. If I'd know that parts could be had to replace and fix them I might
have got deeper in and my technical history might have been very different
from what it is.

[Michael Black]

Post by Brian Reay

Post by Lostgallifreyan

Post by Brian Reay
They tend to be fine for thin steal (eg car panels if you are fitting an
antenna)

Good point. I don't drive or own any large boatanchors so I'm not used to
thinking of non-portable or unsupported surfaces. It may even be easier to
improvise with a slightly wrong hole punch (or aim small and file
outwards) and some large washers than to attempt the way I usually do things.
For small round holes of unspecified size I have never beaten an M3 pilot
hole followed by a tapered reamer, deburring the result with a Stanley blade.
That is VERY cheap, I started out that way and it was a couple of years
before I needed anything better.

Well, as you probably know, real precision holes (eg in watches) are pilot
drilled and reamed, rather
than drilled to size.
The Stanley blade is not, however, part of the procedure. ;-) A fine
broach would be used I would think.
I've repaired a number of pocket watches and clocks but always by hunting
down new parts if needed, or getting them
made. Sadly, my dexterity isn't up to it these days, although it has been
improving recently- much to my surprise- plus I've learned to use my left
hand more. I may rebuild my modest collection of pocket watches, stolen
some years back. They were all ones I had restored, rather than simply
bought working. It is surprise that, even for quite old movements, you can
still locate new, old stock, parts. I recall a trek to a dusting shop in
Notting Hill for a part for a 1920s gold hunter. The shop owner looked at
the details and the broken part, thought for about 2 mins, turn to an array
of 100s of little draws, and produced one. The price? £1. The watch was
worth many times that. I return to the shop many times, it was always the
same. He always had a queue of others with similar wants. He fail once, a
balance staff for an 1883 cylinder escapement. I had that made, £5, inc.
fitting to the balance. He did have a suitable main spring and crystal
glass.
I expect both watches ended up being sold for scrap gold and silver when
the toe rags fenced them. The culprits were caught but the items were not
recovered.

Have you read this book "Longitude", I can't remember the author? (It's
rom about a decade ago.) It's a small book, more like an long essay, about
why a chronometer was needed for travel, and the prize and ultimate
entries to create a working chronometer that could be portable.

Things I'd never thought of. And surely the basis for common watches that
came later. All my life I've had watches, starting with mechanical, and
even those tended to keep pretty good time, likely fallout from that
chronometer work. And of course in recent years, I have a watch that
syncs up from the time signal, so it is very much close to "absolute"
time, for the purposes of everyday timekeeping.

Or a GPS, bought at a garage sale for five dollars, a tiny little thing
but amazing technology that couldn't be built in that small a package (let
alone imagined) forty years ago.

Michael

[Brian Reay]

Post by Michael Black
Have you read this book "Longitude", I can't remember the author? (It's
rom about a decade ago.) It's a small book, more like an long essay,
about why a chronometer was needed for travel, and the prize and
ultimate entries to create a working chronometer that could be portable.

Yes, I recall the book. The storey is a bit sad, the way Harrison was
denied his recognition for years even after clearly met the requirements
and more.

Post by Michael Black
Things I'd never thought of. And surely the basis for common watches
that came later. All my life I've had watches, starting with
mechanical, and even those tended to keep pretty good time, likely
fallout from that chronometer work.

I prefer mechanical watches and have a chronometer watch, it keeps
remarkable time. Setting it correct as the clocks change is adequate.

Post by Michael Black
And of course in recent years, I have a watch that syncs up from the time
signal, so it is very much close to "absolute" time, for the purposes of
everyday timekeeping.

I've been looking at those recently online but would like to see one for
real before buying.

Post by Michael Black
Or a GPS, bought at a garage sale for five dollars, a tiny little thing
but amazing technology that couldn't be built in that small a package
(let alone imagined) forty years ago.

Oh yes. The first computer I programmed, in about 1969 (my secondary
school was one of only a couple to have one) filled a class room. My iPod
would put it to shame.

[gareth]

Yes, your chum's comment is Bovine excrement.
Have you had a lover's tiff?

With your habitual daily output of nasty childish remarks, it is
hardly surprising that you have to go off at a complete tangent
on clocks and watches to get anybody to talk to you.

But how long will it be before you fall out big time with your
new found friends and send for them to be arrested for daring
to disagree with you on the Internet, as you have done so often
to others in these NG?

[Lostgallifreyan]

Post by Lordgnome
Someone once said to me, that precision engineering was the easiest
thing in the world - far easier than having to 'adjust' holes to fit
things and used a lot less material!

They were right. Measure thrice, cut once... I'm about to spend 300 quid on a
small pillar drill, something I avoided doing for years, but I am tired of
seeing the good results of hand work and most of my tools beignj ruined by
the use of one really bad one. I know what peopole say about bad workmen and
tools, but there are bad tools too. :) Pistol-grip drills are the worst...
Never rely on a pilot hole for centring with those, far too many ways chaotic
oscillations can get in to screw things up royally.. I mean, a 2mm hole in
acetal was fine for a subsequent widening to 3.7 for tapping with a fluteless
tap, but try the same methods, no matter how carefully the speed ajuster is
used, and a 5mm bit rips into it with a pattern that resembles a tornado!

Can't beat precision and secure methods. The expense increase is always lower
than the avoided loss.