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| ChrisQ... |
 Posted: Sun Nov 01, 2009 11:48 am |
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Guest
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John Fields wrote:
[quote]On Sun, 01 Nov 2009 14:01:28 +0000, ChrisQ <meru at (no spam) devnull.com> wrote:
miso at (no spam) sushi.com wrote:
I needed to mount a dozen Canon jacks and used the Harbor Freight step
drills in your 3rd link. I used the 3 piece set. Harbor Freight is
well known for selling junk, but these stepped drills work great.
The only problem with step drills is the amount of filing you need to do
afterwards to clean all the burrs.
---
IME, deburring the entry side only requires feeding the drill into the
workpiece until the angular edge of the next step does the debur. Then,
to debur the exit side, all that's needed is to turn the workpiece over
and let that same angular edge do that debur.
[/quote]
That's true if you have access to both sides, but not so good drilling
into the side of a box, where you don't have drill access to the inside.
Problem with materials like ali or plastic is that step drills and hole
saws deform the material and generate quite a bit of heat. That can work
harden the burr, making it a devil to clear. Rotary file bits in the
drill can help, but it's still more hassle and leaves a more untidy job
than a punch in the end.
Regards,
Chris |
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| krw... |
| Posted: Sun Nov 01, 2009 12:33 pm |
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On Sat, 31 Oct 2009 21:50:24 -0700, Archimedes' Lever
<OneBigLever at (no spam) InfiniteSeries.Org> wrote:
[quote]On Sat, 31 Oct 2009 22:12:27 -0500, krw <krw at (no spam) att.bizzzzzzzzzzz> wrote:
On Sat, 31 Oct 2009 19:40:06 -0700, Archimedes' Lever
OneBigLever at (no spam) InfiniteSeries.Org> wrote:
On Sat, 31 Oct 2009 20:13:24 -0500, krw <krw at (no spam) att.bizzzzzzzzzzz> wrote:
On Sat, 31 Oct 2009 17:26:28 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon at (no spam) My-Web-Site.com> wrote:
On Sat, 31 Oct 2009 18:31:09 -0500, krw <krw at (no spam) att.bizzzzzzzzzzz> wrote:
On Sat, 31 Oct 2009 14:19:44 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon at (no spam) My-Web-Site.com> wrote:
On Sat, 31 Oct 2009 17:05:17 -0400, "Michael A. Terrell"
mike.terrell at (no spam) earthlink.net> wrote:
Jim Thompson wrote:
"Slug-Splitter", eh? That sure would have been nice in my days of
punching holes for toob sockets ;-)
In your day, a chassis was chiseled out of stone! ;-)
Naaah! They really were _breadboards_ ;-)
Come on, that was before bread had been invented.
Come on now! Check out the lava-preserved fossils they've dug up at
Pompeii...
Exactly! Dirt was new when you started out. ;-)
isn't that where you're buried ?:-)
Buried? I'm not even buried at work.
That is easy when you have been working above your competency level for
decades.
One must keep challenged. You with your mop, me (lately) with FPGAs.
Microprocessor development was too boring.
You're *so* easy, AlwaysWrong!
Our FPGAs manage 10Gb / second streams. I think you lose again.
[/quote]
"Our"? You certainly don't design with them; too stupid. I lose
nothing, AlwaysWrong. |
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| krw... |
| Posted: Sun Nov 01, 2009 12:43 pm |
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On Sat, 31 Oct 2009 20:30:52 -0400, "Michael A. Terrell"
<mike.terrell at (no spam) earthlink.net> wrote:
[quote]
They are working to improve quality. I've talked to a manager they
move around from store to store to improve their retail stores, and was
told they have had to drop a number of vendors because of quality
problems. Some were replaced because another vendor offered better
quality, and at a lower price. Some of the discussions we had resulted
in changes in their website, as well. Most people don't use that grade
of tool for profession work, but I've run into several guys who swear by
their Pittsburgh Professional wrenches. One was putting two sets in his
work truck and told me he had never had one break, but a lot had been
stolen so he bought two sets at a time. Others told me they used them
working on cars for a living, and had never had a problem. For their
prices, they are hard to beat but you need to look at any tools you plan
on using daily no matter who sells them. I know people who still swear
by Craftsman hand tools because of the lifetime warranty. Then they brag
about how many times Sears has replaced their broken tools.
[/quote]
Hmm. I was at the Montgomery store yesterday but didn't buy much
(just a magnetic parts dish). I was looking at some of their wrenches
but I've bough cheap wrenches before that weren't the marked size.
Kinda makes it tough when the wrench is smaller than the bolt. Maybe
I'll give them a try.
[quote]I have been buying from Harbor Freight for almost 40 years and have
only had one defective tool in that time. It was one of their 6 in 1
screwdrivers, and one piece wasn't properly punched. OTOH, I bought six
that day for half price so I didn't bother to take back a $1.49 tool
that I can fix on my drill press. When I started dealing with them,
they only did mail order and I was buying factory second drill bits by
the pound. Mostly 1/8", since I broke a lot of them drilling out
rivets. A pound would last about 5 years for about $10.
[/quote]
I have bought their drill bits and use the smaller ones a fair bit.
The bigger ones last a long time so I can afford to buy good ones. 
I've had a problem with the temper on screwdrivers and alignment of
the jaws on pliers. HF isn't alone here but they are pretty bad.
I also have their 10" compound sliding miter saw. It's fine for
framing but it's not so great for woodworking. I'll likely replace
it, perhaps with a Bosch or Dewalt, in a year or so. |
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| ehsjr... |
| Posted: Sun Nov 01, 2009 1:00 pm |
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| pimpom... |
| Posted: Sun Nov 01, 2009 1:29 pm |
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Guest
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Jim Thompson wrote:
[quote]On Sun, 1 Nov 2009 17:19:35 +0530, "pimpom"
pimpom at (no spam) invalid.com
wrote:
He was a New Zealander who'd received his Ph.D in the US and
was
more at home with solid-state devices than with tubes. I was
19,
entirely self-taught from the likes of Radiotron Designers's
Handbook
Mine is 4th Edition, 1953 ;-)
Same here. I got my own copy in the late 70s through a friend in[/quote]
the US. It says that it's the 4th edition, 1952 - reproduced
under direction of RCA in April 1953. I had it rebound later and
it's still in very good shape. Still comes in useful for some
things. |
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| Jim Thompson... |
| Posted: Sun Nov 01, 2009 1:46 pm |
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Guest
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On Sun, 1 Nov 2009 23:47:15 +0530, "pimpom" <pimpom at (no spam) invalid.com>
wrote:
[quote]Jim Thompson wrote:
On Sun, 1 Nov 2009 17:19:35 +0530, "pimpom"
pimpom at (no spam) invalid.com
wrote:
He was a New Zealander who'd received his Ph.D in the US and
was
more at home with solid-state devices than with tubes. I was
19,
entirely self-taught from the likes of Radiotron Designers's
Handbook
Mine is 4th Edition, 1953 ;-)
Same here. I got my own copy in the late 70s through a friend in
the US. It says that it's the 4th edition, 1952 - reproduced
under direction of RCA in April 1953. I had it rebound later and
it's still in very good shape. Still comes in useful for some
things.
[/quote]
I bought mine in 1954 I've learned a lot from it, particularly FM
detection... thus my low-frequency FSK patent 4,472,816, actually a
"S-curve" discriminator
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Obama says, "I am NOT a cry baby, Fox is REALLY out to get me!" |
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| Archimedes' Lever... |
| Posted: Sun Nov 01, 2009 2:25 pm |
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Guest
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On Sun, 01 Nov 2009 10:16:33 -0500, Jamie
<jamie_ka1lpa_not_valid_after_ka1lpa_ at (no spam) charter.net> wrote:
[quote]Henceforward...
[/quote]
Grow the fuck up. |
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| Archimedes' Lever... |
| Posted: Sun Nov 01, 2009 2:27 pm |
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Guest
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On Sun, 01 Nov 2009 11:33:02 -0600, krw <krw at (no spam) att.bizzzzzzzzzzz> wrote:
[quote]"Our"? You certainly don't design with them;
[/quote]
You have no clue, as usual.
[quote]too stupid.
[/quote]
You certainly are.
[quote]I lose
nothing,
[/quote]
Nothing from nothing leaves nothing. Basic math, nothing boy. |
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| Michael A. Terrell... |
| Posted: Sun Nov 01, 2009 2:39 pm |
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Guest
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pimpom wrote:
[quote]
Jim Thompson wrote:
On Sun, 1 Nov 2009 17:19:35 +0530, "pimpom"
pimpom at (no spam) invalid.com
wrote:
He was a New Zealander who'd received his Ph.D in the US and
was
more at home with solid-state devices than with tubes. I was
19,
entirely self-taught from the likes of Radiotron Designers's
Handbook
Mine is 4th Edition, 1953 ;-)
Same here. I got my own copy in the late 70s through a friend in
the US. It says that it's the 4th edition, 1952 - reproduced
under direction of RCA in April 1953. I had it rebound later and
it's still in very good shape. Still comes in useful for some
things.
[/quote]
It's available online in PDF format for free.
--
The movie 'Deliverance' isn't a documentary! |
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| Michael A. Terrell... |
| Posted: Sun Nov 01, 2009 2:42 pm |
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Guest
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pimpom wrote:
[quote]
Michael A. Terrell wrote:
Jim Thompson wrote:
"Slug-Splitter", eh? That sure would have been nice in my
days of
punching holes for toob sockets ;-)
In your day, a chassis was chiseled out of stone! ;-)
The last time I used knockout punches was almost 40 years ago
during the only time I ever worked under someone else. Tubes were
still a more viable option than solid-state devices for many
applications, especially in places like India. I remember having
a mild argument with my boss when he asked me to design and
construct a constant-current, high-voltage supply for
electrophoretic work in a medical research lab.
He was a New Zealander who'd received his Ph.D in the US and was
more at home with solid-state devices than with tubes. I was 19,
entirely self-taught from the likes of Radiotron Designers's
Handbook and whaterver scraps of literature I could find. I
wanted to use an EL84 at its "design maximum" ratings and he
claimed that active devices should never be operated anywhere
near their maximum ratings. I had my way, and the lab used the
instrument for many years.
[/quote]
I had a nice collection of Greenlee punches, but someone stole the
whole set. It would be well over $1000 to replace them, these days. The
most expensive is the rectangular punch for 4PDT P&B relay sockets.
--
The movie 'Deliverance' isn't a documentary! |
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| pimpom... |
| Posted: Sun Nov 01, 2009 2:55 pm |
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Guest
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Jim Thompson wrote:
[quote]On Sun, 1 Nov 2009 23:47:15 +0530, "pimpom"
pimpom at (no spam) invalid.com
wrote:
Jim Thompson wrote:
On Sun, 1 Nov 2009 17:19:35 +0530, "pimpom"
pimpom at (no spam) invalid.com
wrote:
He was a New Zealander who'd received his Ph.D in the US and
was
more at home with solid-state devices than with tubes. I was
19,
entirely self-taught from the likes of Radiotron Designers's
Handbook
Mine is 4th Edition, 1953 ;-)
Same here. I got my own copy in the late 70s through a friend
in
the US. It says that it's the 4th edition, 1952 - reproduced
under direction of RCA in April 1953. I had it rebound later
and
it's still in very good shape. Still comes in useful for some
things.
I bought mine in 1954 I've learned a lot from it,
particularly FM
detection... thus my low-frequency FSK patent 4,472,816,
actually a
"S-curve" discriminator ;-)
[/quote]
I was still pre-school then  Taking into account the state of
the art at the time any technical publication is published, and
within the limits of my own experience, I think RDH was the best
book ever on electronics in that it had just the right blend of
theory and practical considerations. It's still highly prized by
tube enthusiasts. |
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| pimpom... |
| Posted: Sun Nov 01, 2009 2:57 pm |
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Guest
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ChrisQ wrote:
[quote]pimpom wrote:
He was a New Zealander who'd received his Ph.D in the US and
was
more at home with solid-state devices than with tubes. I was
19,
entirely self-taught from the likes of Radiotron Designers's
Handbook and whaterver scraps of literature I could find. I
wanted to use an EL84 at its "design maximum" ratings and he
claimed that active devices should never be operated anywhere
near their maximum ratings. I had my way, and the lab used the
instrument for many years.
School teaches you the theory, but real world experience
teaches you
what is possible ...
[/quote]
That incident must have left an impression with my boss. When the
internet arrived in my region almost thirty years later, I
managed to find the postal address of one of his former work
places. I sent him a letter and in his reply by email, he
mentioned the incident and graciously said "You taught me a good
lesson that day".
We corresponded for awhile and then tapered off, and I lost his
contact info. Sure wish I could find him again - if he's still
alive. He must be well over 70 by now. |
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| Michael A. Terrell... |
| Posted: Sun Nov 01, 2009 3:03 pm |
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Guest
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krw wrote:
[quote]
On Sat, 31 Oct 2009 20:30:52 -0400, "Michael A. Terrell"
mike.terrell at (no spam) earthlink.net> wrote:
They are working to improve quality. I've talked to a manager they
move around from store to store to improve their retail stores, and was
told they have had to drop a number of vendors because of quality
problems. Some were replaced because another vendor offered better
quality, and at a lower price. Some of the discussions we had resulted
in changes in their website, as well. Most people don't use that grade
of tool for profession work, but I've run into several guys who swear by
their Pittsburgh Professional wrenches. One was putting two sets in his
work truck and told me he had never had one break, but a lot had been
stolen so he bought two sets at a time. Others told me they used them
working on cars for a living, and had never had a problem. For their
prices, they are hard to beat but you need to look at any tools you plan
on using daily no matter who sells them. I know people who still swear
by Craftsman hand tools because of the lifetime warranty. Then they brag
about how many times Sears has replaced their broken tools.
Hmm. I was at the Montgomery store yesterday but didn't buy much
(just a magnetic parts dish). I was looking at some of their wrenches
but I've bough cheap wrenches before that weren't the marked size.
Kinda makes it tough when the wrench is smaller than the bolt. Maybe
I'll give them a try.
I have been buying from Harbor Freight for almost 40 years and have
only had one defective tool in that time. It was one of their 6 in 1
screwdrivers, and one piece wasn't properly punched. OTOH, I bought six
that day for half price so I didn't bother to take back a $1.49 tool
that I can fix on my drill press. When I started dealing with them,
they only did mail order and I was buying factory second drill bits by
the pound. Mostly 1/8", since I broke a lot of them drilling out
rivets. A pound would last about 5 years for about $10.
I have bought their drill bits and use the smaller ones a fair bit.
The bigger ones last a long time so I can afford to buy good ones.
I've had a problem with the temper on screwdrivers and alignment of
the jaws on pliers. HF isn't alone here but they are pretty bad.
I also have their 10" compound sliding miter saw. It's fine for
framing but it's not so great for woodworking. I'll likely replace
it, perhaps with a Bosch or Dewalt, in a year or so.
[/quote]
I just bought an old Crftsman 10" belt drive table saw to replace the
one that has an internal motor that quit. Both were built by Emerson
over 15 years ago. The internal motor was a custom design, and used an
externally mounted Klixon thermal motor starter that is no longer
availible. the motor is no longer availible, as well. The belt drive
saw is older, but uses a stock 1/2 HP motor and there is very little
that can't be repaired or make with a few metalworking tools. I'm going
to replace all the bearings as P.M., and the rubber covered levelers
will be replaced with some 4" stem casters. It is so heavy that it takes
two people to lift it out of my truck, or to move it.
I have several other Crftsman saws that my dad left when he moved
north last year. A couple radial arm saws, a miter saw and a couple
circular saws. I also have the little 10" table saw from Harbor freight
that I use to cut luan plywood. I bought it for $69 a few months ago.
Its nothing special, but it works for what I want. I am replacing some
paper tray bins with plywood, and i am going to build some 2'*2'*2'
boxes that stack
--
The movie 'Deliverance' isn't a documentary! |
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| Michael A. Terrell... |
| Posted: Sun Nov 01, 2009 3:06 pm |
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| pimpom... |
| Posted: Sun Nov 01, 2009 3:13 pm |
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Guest
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Michael A. Terrell wrote:
[quote]pimpom wrote:
Jim Thompson wrote:
On Sun, 1 Nov 2009 17:19:35 +0530, "pimpom"
pimpom at (no spam) invalid.com
wrote:
He was a New Zealander who'd received his Ph.D in the US and
was
more at home with solid-state devices than with tubes. I was
19,
entirely self-taught from the likes of Radiotron Designers's
Handbook
Mine is 4th Edition, 1953 ;-)
Same here. I got my own copy in the late 70s through a friend
in
the US. It says that it's the 4th edition, 1952 - reproduced
under direction of RCA in April 1953. I had it rebound later
and
it's still in very good shape. Still comes in useful for some
things.
It's available online in PDF format for free.
[/quote]
Thanks for the info. Downloading it now, just in case. I even saw
a pdf copy of my first book on electronics: Audels Radioman's
Guide. |
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