I have an oval picture for which I would like to make a frame. I can
draw the oval

As I see it there would be two parts in cutting the oval.
----- The oval cut that would eventually frame the picture.
----- The rabbet cut to hold the picture.

I have the following tools available to me:

1. Table saw (I have no idea how this could be used)
2. Standard size non plunge router with router table.
3. Dremmel with spiral cut bit and other router bits.
4. Jig saw.
5. Drill press with brad point and Forstner bits.

Can I get suggestions making the cutout for the picture.

Finishing the outside edges is obvious.

On 3/29/2010 12:08 PM, Keith Nuttle wrote:
I have an oval picture for which I would like to make a frame. I can
draw the oval

As I see it there would be two parts in cutting the oval.
----- The oval cut that would eventually frame the picture.
----- The rabbet cut to hold the picture.

I have the following tools available to me:

1. Table saw (I have no idea how this could be used)
2. Standard size non plunge router with router table.
3. Dremmel with spiral cut bit and other router bits.
4. Jig saw.
5. Drill press with brad point and Forstner bits.

Can I get suggestions making the cutout for the picture.

More Information:

Major axis length (longest "diameter")
Minor axis length (shortest "diameter")
Stock thickness.

One more tool:

Analytic Geometry

Let 2a = major axis
let 2b = minor axis

There will be two foci (on the major axis)

The distance from the center to either focus is sqrt(a^2 - b^2)

The equation, if you want to plot an ellipse is

x^2/a^2 + y^2/b^2 = 1

Or, if you want to construct an ellipse:

push a pin into each of the foci
tie a string to each pin so that if you pull the string taut with a
pencil point, the pencil point will just touch a point at a distance b
from the center on the perpendicular bisector of a line between the two
foci.

It sounds a lot more complicated than it really is

Once you've drawn it, you can freehand rout the opening - and can then
use a rabbet bit to cut for the glass and photo.

FWIW - this project begs for a spindle sander. ;-)

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

On Mar 29, 10:08*am, Keith Nuttle wrote:
I have an oval picture for which I would like to make a frame. I can


Can I get suggestions making the cutout for the picture.

Finishing the outside edges is obvious.

You would probably go with an elipse cutting jig\tramel something like
this (there are lots of them out there)
http://www.woodweb.com/knowledge_bas...Ellipses..html

The basic steps one would typically follow is...
- Cut a template from MDF or other easy to cut material using the jig
- Use the template to draw the shape on your blank stock
- Cut the blank stock close to finish size with band\jig\scroll\ect.
saw
- Use the template to finish rout the real part using a bearing
\pattern bit.

For an oval you might want to be creative on the glue up of some stock
using sticks to get a rough shape, maybe using half lap joints.

Finishing the outside edges is obvious.

P.S. Thanks for the meaty actual woodworking post. ;^)

"Keith Nuttle" wrote in message
...
I have an oval picture for which I would like to make a frame. I can draw
the oval

As I see it there would be two parts in cutting the oval.
----- The oval cut that would eventually frame the picture.
----- The rabbet cut to hold the picture.

I have the following tools available to me:

1. Table saw (I have no idea how this could be used)
2. Standard size non plunge router with router table.
3. Dremmel with spiral cut bit and other router bits.
4. Jig saw.
5. Drill press with brad point and Forstner bits.

Can I get suggestions making the cutout for the picture.

Finishing the outside edges is obvious.


If you only need one and can draw it, draw it up and cut it out with a
jigsaw. Leave a bit of excess. Put a sanding drum in your drill press and
sand to the line. Use a rabbet bit for the recess.

Keith Nuttle wrote in
:

I have an oval picture for which I would like to make a
frame. I can draw the oval

As I see it there would be two parts in cutting the oval.
----- The oval cut that would eventually frame the picture.
----- The rabbet cut to hold the picture.

I have the following tools available to me:

1. Table saw (I have no idea how this could be used)
2. Standard size non plunge router with router table.
3. Dremmel with spiral cut bit and other router bits.
4. Jig saw.
5. Drill press with brad point and Forstner bits.

Can I get suggestions making the cutout for the picture.

Finishing the outside edges is obvious.

I'd get a piece of MDF to use for a template. After
deciphering Morris' instructions on how to draw an oval, cut
it out close with your jigsaw. Smooth it up with a drum sander
in your drill press. Cut the real material with the jigsaw as
close as you can to the correct shape. Using double-stick
tape, adhere the template to the real material. Then use a
flush trim router bit to copy the shape of your template. If
you can get this far the rabbet is the easy part.

Larry

Two thumbtacks and a closed string. Calculate the foci's points
from the major and minor axis. Simple algebra.
Once you know - then any size can be done.

http://en.wikipedia.org/wiki/Ellipse

simply :

x^2/a^2 + y^2/b^2 = 1
where b^2 = a^2 - c^2.

where a is 1/2 long diameter and b = 1/2 short diameter
and c is 1/2 the length between pins.


Martin

SonomaProducts.com wrote:
On Mar 29, 10:08 am, Keith Nuttle wrote:
I have an oval picture for which I would like to make a frame. I can

Can I get suggestions making the cutout for the picture.

Finishing the outside edges is obvious.

You would probably go with an elipse cutting jig\tramel something like
this (there are lots of them out there)
http://www.woodweb.com/knowledge_bas..._Ellipses.html

The basic steps one would typically follow is...
- Cut a template from MDF or other easy to cut material using the jig
- Use the template to draw the shape on your blank stock
- Cut the blank stock close to finish size with band\jig\scroll\ect.
saw
- Use the template to finish rout the real part using a bearing
\pattern bit.

For an oval you might want to be creative on the glue up of some stock
using sticks to get a rough shape, maybe using half lap joints.

In my opinion if you are going to do it freehand, then skip the
template step and just free hand the blank. My whole reason for a
template is to use a trammel and\or other precise methods to form the
shape and it is easier and cleaner to hog it out from MDF. Then you
can free hand the blank down to very close to the actual finish shape
and use the template to guide a trim pass.

On Mar 29, 5:52*pm, Larry wrote:
Keith Nuttle wrote :





I have an oval picture for which I would like to make a
frame. I can draw the oval

As I see it there would be two parts in cutting the oval.
----- The oval cut that would eventually frame the picture.
----- The rabbet cut to hold the picture.

I have the following tools available to me:

1. Table saw (I have no idea how this could be used)
2. Standard size non plunge router with router table.
3. Dremmel with spiral cut bit and other router bits.
4. Jig saw.
5. Drill press with brad point and Forstner bits.

Can I get suggestions making the cutout for the picture.

Finishing the outside edges is obvious.

I'd get a piece of MDF to use for a template. After
deciphering Morris' instructions on how to draw an oval, cut
it out close with your jigsaw. Smooth it up with a drum sander
in your drill press. Cut the real material with the jigsaw as
close as you can to the correct shape. Using double-stick
tape, adhere the template to the real material. Then use a
flush trim router bit to copy the shape of your template. If
you can get this far the rabbet is the easy part.

Larry- Hide quoted text -

- Show quoted text -

On 3/29/2010 12:08 PM, Keith Nuttle wrote:
I have an oval picture for which I would like to make a frame. I can
draw the oval

I did a cursory search but can't find it, but David J. Marks had a
helluva good episode on making an oval mirror(IRRC) frame ... would
really be worthwhile tracking down the show.

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)

Swingman wrote:
On 3/29/2010 12:08 PM, Keith Nuttle wrote:

I have an oval picture for which I would like to make a frame. I can
draw the oval


I did a cursory search but can't find it, but David J. Marks had a
helluva good episode on making an oval mirror(IRRC) frame ... would
really be worthwhile tracking down the show.


If I recall many years ago either ShopNotes or Woodsmith magazine had
plans for a router jig to make elliptical frames. I believe it used
1/4" threaded rod to allow adjustment to various sizes. The router
mounted directly to the jig.

I tried a Google search and came up blank. Anyone have their index(s)
(I'm pretty sure it was ShopNotes).

--
Jack Novak
Buffalo, NY - USA

On 3/29/2010 1:20 PM, Morris Dovey wrote:
On 3/29/2010 12:08 PM, Keith Nuttle wrote:
I have an oval picture for which I would like to make a frame. I can
draw the oval

As I see it there would be two parts in cutting the oval.
----- The oval cut that would eventually frame the picture.
----- The rabbet cut to hold the picture.

I have the following tools available to me:

1. Table saw (I have no idea how this could be used)
2. Standard size non plunge router with router table.
3. Dremmel with spiral cut bit and other router bits.
4. Jig saw.
5. Drill press with brad point and Forstner bits.

Can I get suggestions making the cutout for the picture.

More Information:

Major axis length (longest "diameter")
Minor axis length (shortest "diameter")
Stock thickness.

One more tool:

Analytic Geometry

Let 2a = major axis
let 2b = minor axis

There will be two foci (on the major axis)

The distance from the center to either focus is sqrt(a^2 - b^2)

The equation, if you want to plot an ellipse is

x^2/a^2 + y^2/b^2 = 1

Or, if you want to construct an ellipse:

push a pin into each of the foci
tie a string to each pin so that if you pull the string taut with a
pencil point, the pencil point will just touch a point at a distance b
from the center on the perpendicular bisector of a line between the two
foci.

It sounds a lot more complicated than it really is

Once you've drawn it, you can freehand rout the opening - and can then
use a rabbet bit to cut for the glass and photo.

FWIW - this project begs for a spindle sander. ;-)


I'm such a dumb redneck. I probably would have just traced the
picture. Then told the wife I need a bandsaw and a spindle sander.

LdB

On 3/30/2010 12:55 PM, LdB wrote:

I'm such a dumb redneck. I probably would have just traced the picture.
Then told the wife I need a bandsaw and a spindle sander.

Be a _smart_ redneck - tell 'er you need a CNC router and /maybe/ a
bandsaw and a spindle sander after that. :-D

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

On 3/30/2010 3:40 PM, dadiOH wrote:
Morris Dovey wrote:

One more tool:

Analytic Geometry

I detested that class.

Prof was a Yugoslav, didn't have a great command of English. He had been a
partisan and his throat had been cut ear to ear; no idea if that affected
his speech but he was next to impossible to understand. It was the only
class I *ever* had to repeat.

Bummer. I can sympathize because my freshman physics class was a Korean
who had a similar handicap, and who made up for it by screaming his
lectures. I dropped the course after a week and restarted the following
quarter with a different prof, along with all the folks who'd stuck it
out and failed the course.

The guy who taught my Calculus and Analytic Geometry class, by contrast,
was clear, soft-spoken, and wrote everything on the blackboard as he
lectured. He wrote with his right hand and erased with his left as he
went, with pauses as he walked back to the left side of the board. It
would have been humorous if I hadn't been in a permanent panic to get
things into my notes before they disappeared.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

LdB wrote in
m:


I'm such a dumb redneck. I probably would have just traced the
picture. Then told the wife I need a bandsaw and a spindle sander.

LdB



You also need a welder and file set to make the cut with a bandsaw and not
cut through the frame. Oh, and something to cut the bandsaw blade again
after it's done.

Puckdropper
--
Never teach your apprentice everything you know.

On 3/30/2010 3:13 PM, Morris Dovey wrote:

The guy who taught my Calculus and Analytic Geometry class, by contrast,
was clear, soft-spoken, and wrote everything on the blackboard as he
lectured. He wrote with his right hand and erased with his left as he
went, with pauses as he walked back to the left side of the board. It
would have been humorous if I hadn't been in a permanent panic to get
things into my notes before they disappeared.

Just having the youngest out of college, I know that taking notes in
class today can be as simple as hitting a button and letting the
recording device/laptop tape the lecture.

I can't help but think that letting technology do it for you probably
skips a vital link in the synapses that the process of writing it down
completes. I was thinking about that the other day when responding to
the thread on width, length, etc.

Botany prof drew pictures of plant cell structures on a blackboard and
students were required to handcopy them to a notebook that was part of
the course grade ....and today, 45 years later, those pictures I copied
from that blackboard are still vivid in my mind.

Also had a Korean grad student that taught an advanced math course full
of words like 'vector-value', 'differential', etc. that he couldn't
pronounce in an understandable manner to anyone ... a brilliant guy, but
he cost most of us a grade point or two.

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)

On 3/30/2010 4:49 PM, Swingman wrote:
On 3/30/2010 3:13 PM, Morris Dovey wrote:

The guy who taught my Calculus and Analytic Geometry class, by contrast,
was clear, soft-spoken, and wrote everything on the blackboard as he
lectured. He wrote with his right hand and erased with his left as he
went, with pauses as he walked back to the left side of the board. It
would have been humorous if I hadn't been in a permanent panic to get
things into my notes before they disappeared.

Just having the youngest out of college, I know that taking notes in
class today can be as simple as hitting a button and letting the
recording device/laptop tape the lecture.

I can't help but think that letting technology do it for you probably
skips a vital link in the synapses that the process of writing it down
completes. I was thinking about that the other day when responding to
the thread on width, length, etc.

Botany prof drew pictures of plant cell structures on a blackboard and
students were required to handcopy them to a notebook that was part of
the course grade ....and today, 45 years later, those pictures I copied
from that blackboard are still vivid in my mind.

Also had a Korean grad student that taught an advanced math course full
of words like 'vector-value', 'differential', etc. that he couldn't
pronounce in an understandable manner to anyone ... a brilliant guy, but
he cost most of us a grade point or two.


One of the best teachers I ever had was my analytical geometry teacher
in high school. I had many more in college but he was the best.

As for technology in the class room while there are negatives, there are
all so some strong positives. If I have a computer in physical
chemistry I may have a better understanding of how the various equation
performed.

Of course you go to school to learn what you do not know, and to learn
to learn.

On 3/30/2010 4:07 PM, Keith Nuttle wrote:

As for technology in the class room while there are negatives, there are
all so some strong positives. If I have a computer in physical chemistry
I may have a better understanding of how the various equation performed.

I had a computer ... "me", with a slide rule.

Of course you go to school to learn what you do not know, and to learn
to learn.

Well said ...

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)

Keith Nuttle wrote:

Of course you go to school to learn what you do not know, and to learn
to learn.

Gosh, I need to go back--I think I forgot to do something! : )

On 3/30/2010 4:13 PM, Morris Dovey wrote:
On 3/30/2010 3:40 PM, dadiOH wrote:
Morris Dovey wrote:

One more tool:

Analytic Geometry

I detested that class.

Prof was a Yugoslav, didn't have a great command of English. He had
been a
partisan and his throat had been cut ear to ear; no idea if that affected
his speech but he was next to impossible to understand. It was the only
class I *ever* had to repeat.

Bummer. I can sympathize because my freshman physics class was a Korean
who had a similar handicap, and who made up for it by screaming his
lectures. I dropped the course after a week and restarted the following
quarter with a different prof, along with all the folks who'd stuck it
out and failed the course.

The guy who taught my Calculus and Analytic Geometry class, by contrast,
was clear, soft-spoken, and wrote everything on the blackboard as he
lectured. He wrote with his right hand and erased with his left as he
went, with pauses as he walked back to the left side of the board. It
would have been humorous if I hadn't been in a permanent panic to get
things into my notes before they disappeared.

I learned that I do best to just get a good text and work through it.

There used to be a schaum's outline on analytic geometry--been out of
print for 20 years though.

"Swingman" wrote in message
...
On 3/30/2010 4:07 PM, Keith Nuttle wrote:

As for technology in the class room while there are negatives,
there are
all so some strong positives. If I have a computer in physical
chemistry
I may have a better understanding of how the various equation
performed.

I had a computer ... "me", with a slide rule.

They're becoming forgotten. Slide rules put man on the moon.
Back in HS and college, the classes like Physics and Chem had a
half bushel basket by the door with school slide rules for the
kids without their own.
--
Nonny
Suppose you were an idiot.
And suppose you were a member
of Congress.... But then I repeat myself.'

-Mark Twain
..

On 3/30/2010 5:01 PM, Nonny wrote:

"Swingman" wrote in message
...
On 3/30/2010 4:07 PM, Keith Nuttle wrote:

As for technology in the class room while there are negatives, there are
all so some strong positives. If I have a computer in physical chemistry
I may have a better understanding of how the various equation performed.

I had a computer ... "me", with a slide rule.

They're becoming forgotten. Slide rules put man on the moon. Back in HS
and college, the classes like Physics and Chem had a half bushel basket
by the door with school slide rules for the kids without their own.

Same mathematical functions as a computer, but these days the computer
is _much_ faster.

That wasn't always the case, even with electronic digital computers.

When I was in the Army we routinely beat "Freddie" FADAC (Field
Artillery Digital Automatic Computer) with our slide rules in the Fire
Direction Centers ... in combat we seldom used "Freddie" to actually
fire missions, just to check our slide rule results, if we didn't have
to wait on it.

It wasn't a matter of arithmetic trust, FADAC was just too damn slow.

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)

On 3/30/2010 6:01 PM, Nonny wrote:

"Swingman" wrote in message
...
On 3/30/2010 4:07 PM, Keith Nuttle wrote:

As for technology in the class room while there are negatives, there are
all so some strong positives. If I have a computer in physical chemistry
I may have a better understanding of how the various equation performed.

I had a computer ... "me", with a slide rule.

They're becoming forgotten. Slide rules put man on the moon. Back in HS
and college, the classes like Physics and Chem had a half bushel basket
by the door with school slide rules for the kids without their own.

When I was in High School in the late 50's I paid 25 dollars for a cheap
slide rule. There was no way I could have afforded the expensive ones.

Today when you go to flea markets or antique stores you can pick up the
most expensive for 5 or 10 dollars/ with case.

My favorite slide rule was the circular slide rule. For some spectra
conversion in IR or UV you could make the calculation on the circular
slide rule faster that any calculator today.

On 3/30/2010 6:53 PM, Keith Nuttle wrote:

My favorite slide rule was the circular slide rule. For some spectra
conversion in IR or UV you could make the calculation on the circular
slide rule faster that any calculator today.

Do you remember your first electronic calculator? I got a TI-30 (IIRC)
when I went back to school briefly after the service. We weren't even
allowed to bring them to class, much less take a test with it.

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)

On 3/30/2010 8:37 PM, Swingman wrote:
On 3/30/2010 6:53 PM, Keith Nuttle wrote:

My favorite slide rule was the circular slide rule. For some spectra
conversion in IR or UV you could make the calculation on the circular
slide rule faster that any calculator today.

Do you remember your first electronic calculator? I got a TI-30 (IIRC)
when I went back to school briefly after the service. We weren't even
allowed to bring them to class, much less take a test with it.

TI-30? That is only about 20 years old. The electronic calculator I am
talking about was bought in 1970. It had a big nixy(sp?) display and
was the size of a typewriter. It was significantly better that the old
mechanical one. It did X / + - and had 12 rows of 10 keys in each row.
Took several seconds to do simply + and - calculations and longer to
do X and /.

"Swingman" wrote in message
...
On 3/30/2010 6:53 PM, Keith Nuttle wrote:

My favorite slide rule was the circular slide rule. For some
spectra
conversion in IR or UV you could make the calculation on the
circular
slide rule faster that any calculator today.

Do you remember your first electronic calculator? I got a TI-30
(IIRC) when I went back to school briefly after the service. We
weren't even allowed to bring them to class, much less take a
test with it.

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)

HP gave me a 35 for my work on the 80. That was a long time
ago.

--
Nonny
Suppose you were an idiot.
And suppose you were a member
of Congress.... But then I repeat myself.'

-Mark Twain
..

"Keith Nuttle" wrote in message
...
On 3/30/2010 8:37 PM, Swingman wrote:
On 3/30/2010 6:53 PM, Keith Nuttle wrote:

My favorite slide rule was the circular slide rule. For some
spectra
conversion in IR or UV you could make the calculation on the
circular
slide rule faster that any calculator today.

Do you remember your first electronic calculator? I got a TI-30
(IIRC)
when I went back to school briefly after the service. We
weren't even
allowed to bring them to class, much less take a test with it.

TI-30? That is only about 20 years old. The electronic
calculator I am talking about was bought in 1970. It had a big
nixy(sp?) display and was the size of a typewriter. It was
significantly better that the old mechanical one. It did X /
+ - and had 12 rows of 10 keys in each row. Took several seconds
to do simply + and - calculations and longer to do X and /.

Monroe 990 with 16 digit display. The Frieden was better, with
its initial 3-level version of RPN, but who woulda' thunk it?

--
Nonny
Suppose you were an idiot.
And suppose you were a member
of Congress.... But then I repeat myself.'

-Mark Twain
..

On 3/30/2010 9:22 PM, Keith Nuttle wrote:

TI-30? That is only about 20 years old.

Early to mid 70's .. but I may be wrong about the model #. I do recall
that is was designated as a "student calculator".

Don't hold me to the exact particulars.

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)

On 3/30/2010 10:33 PM, Nonny wrote:

"Swingman" wrote in message
...
On 3/30/2010 6:53 PM, Keith Nuttle wrote:

My favorite slide rule was the circular slide rule. For some spectra
conversion in IR or UV you could make the calculation on the circular
slide rule faster that any calculator today.

Do you remember your first electronic calculator? I got a TI-30 (IIRC)
when I went back to school briefly after the service. We weren't even
allowed to bring them to class, much less take a test with it.

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)

HP gave me a 35 for my work on the 80. That was a long time ago.

My first was an HP45--marvelous when it worked. Four hundred bucks and
it wasn't reliable. Seems downright primitive today.

In 1970 I bought with a loan app - a $600 calculator from a business supply
company. It was a 12 digit Nixie tube four-banger with memory. It saved
the beloved and I when doing grades. A few more years later I had a machine
language computer.

I did logs on that 4 banger - trig sin and cos and tan. There were some
very creative guys learning tricks and approximations and small formulas
that one could get good numbers.

The company was Cannon. I scrapped out the machine in about 1995 or so.
It had a bad supply - HV likely leaky and the controller wasn't up to speed.

Several years after the first TI and HP came on the scene - and we both
died. $150 for a full blown ? - I think we still owned about that much
on the Nixie box. TI's SR-50 ... Been a TI and HP guy since.
Went to HP in 85 and back to TI in 2008.

I had a small circular slide rule, Dad had a tubular slide rule.
We both still have slide rules in our desks and use them.
Faster than getting out the banger and entering the number.

Long calc's or complex ones bring out the box - one or the other.

Martin

Keith Nuttle wrote:
On 3/30/2010 8:37 PM, Swingman wrote:
On 3/30/2010 6:53 PM, Keith Nuttle wrote:

My favorite slide rule was the circular slide rule. For some spectra
conversion in IR or UV you could make the calculation on the circular
slide rule faster that any calculator today.

Do you remember your first electronic calculator? I got a TI-30 (IIRC)
when I went back to school briefly after the service. We weren't even
allowed to bring them to class, much less take a test with it.

TI-30? That is only about 20 years old. The electronic calculator I am
talking about was bought in 1970. It had a big nixy(sp?) display and
was the size of a typewriter. It was significantly better that the old
mechanical one. It did X / + - and had 12 rows of 10 keys in each row.
Took several seconds to do simply + and - calculations and longer to do
X and /.

On 3/30/2010 9:22 PM, Keith Nuttle wrote:

TI-30? That is only about 20 years old.

Nope ... mid 70's.

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)

On 3/30/2010 7:37 PM, Swingman wrote:

Do you remember your first electronic calculator? I got a TI-30 (IIRC)
when I went back to school briefly after the service. We weren't even
allowed to bring them to class, much less take a test with it.

I held off buying a pocket calculator until I could get one that was
both programmable and affordable.

I ended up buying an HP-25. I still have it stored away somewhere, and
the last time I powered it up, it still ran.

I used that until 1980 when I got a Radio Shack TRS-80 Pocket Computer
that could run (sorta) BASIC programs, read/write to a cassette drive,
and print on a cash register size tape. It's here on my desk needing new
batteries (and a new ribbon for the printer).

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

On 3/31/2010 9:48 PM, Martin H. Eastburn wrote:
In 1970 I bought with a loan app - a $600 calculator from a business supply
company. It was a 12 digit Nixie tube four-banger with memory. It saved
the beloved and I when doing grades. A few more years later I had a machine
language computer.

I did logs on that 4 banger - trig sin and cos and tan. There were some
very creative guys learning tricks and approximations and small formulas
that one could get good numbers.

The company was Cannon. I scrapped out the machine in about 1995 or so.
It had a bad supply - HV likely leaky and the controller wasn't up to
speed.

Several years after the first TI and HP came on the scene - and we both
died. $150 for a full blown ? - I think we still owned about that much
on the Nixie box. TI's SR-50 ... Been a TI and HP guy since.
Went to HP in 85 and back to TI in 2008.

I had a small circular slide rule, Dad had a tubular slide rule.
We both still have slide rules in our desks and use them.
Faster than getting out the banger and entering the number.

Long calc's or complex ones bring out the box - one or the other.

Just a comment but I picked up a piece of software a while back called
"The Mathematical Explorer" for about a hundred bucks. Turned out to be
the Mathematica 6 core with a couple of features turned off and without
some of the add-on packages. They've discontinued that now and have a
full-featured version sold for non-commercial use for 400 bucks or so.
If you happen to find the older one though for the low price it's well
worth getting if you ever have to do any kind of serious computation.


Martin

Keith Nuttle wrote:
On 3/30/2010 8:37 PM, Swingman wrote:
On 3/30/2010 6:53 PM, Keith Nuttle wrote:

My favorite slide rule was the circular slide rule. For some spectra
conversion in IR or UV you could make the calculation on the circular
slide rule faster that any calculator today.

Do you remember your first electronic calculator? I got a TI-30 (IIRC)
when I went back to school briefly after the service. We weren't even
allowed to bring them to class, much less take a test with it.

TI-30? That is only about 20 years old. The electronic calculator I am
talking about was bought in 1970. It had a big nixy(sp?) display and
was the size of a typewriter. It was significantly better that the old
mechanical one. It did X / + - and had 12 rows of 10 keys in each row.
Took several seconds to do simply + and - calculations and longer to
do X and /.