Subject: Re: Egg drop mechanism
From: "Alan K. Gideon"
Date: Fri, 08 Nov 1996 17:28:09 -0500
mchalefla@worldnet.att.net wrote:
>
>
> Let's clarify something, Alan Gideon, Tom Austin and Thomas Wynsen...
>
> Who do you punks think that you are, criticizing me in such a way?
> Perhaps it's because I am new to USENET that I have taken offense to the
> replies to my simple query. Or perhaps it's because I take any
> criticims of my own intelligence very seriously. However, if you wish
> to preach to me the importance of doing this project on my own, then you
> obviously do not wish to offer advice, which is all that I asked of you.
> Did I ask for a sermon on the benefits of doing my homework myself? I
> think not. Next time, don't waste your typing time or my reading time
> for your useless and pointless comments.
>
> Kevin
Kevin seems to have missed the point of addressing a professional usenet
group. It has been my observation that the members are more than
willing to address problems that individual members have tried to solve
and found roadblocks of one sort or another.
Kevin,
Once you have put together the basic thoughts about how you plan to
solve _your_ problem, come talk to us again. I think you will find a
number of people willing to help you get over the sticking points. 8^)
--
Alan K. Gideon, P.E. | Naval Architect & Marine Engineer
| akgideon@mindspring.com
Subject: Re: X-33 info....help!!
From: Satchi Venkataraman
Date: Fri, 08 Nov 1996 14:39:03 -0500
manuel magrane wrote:
>
> Hello,
> I am an engineering student at CSUN, and I am writing a
> paper on the DC-X/DC-XA/X-33 reusable rocket prototype, more specifically
> on the materials (Al-Li alloy). Does anybody know of any references
> whether it be on the internet, books, or magazines I can be pin-pointed
> to? I have tried several periodical resources, but they are too skimpy
> when it
> comes down to specifics. Any information is appreciated! Personal email is
> preferred.
>
> Thanks a lot,
> --------------------------------------------------------------
> \ / Manny Magrane
> |\ /| CSUN - SECS Dept. of Mech. Engineering
> | \ / | hbmen026@csun1.csun.edu
> \ / \/ \ /
> \_/ \_/
> "Success is more attitude than aptitude."
> - Unknown
> "If opportunity doesn't knock, build a door."
> - Milton Berle
> -----------------------------------------------
>
>
Check the followiong web site which has a lot of relevant data for the
resuauble launch vehicle design.
http://calvin.ksc.nasa.gov:1080/nexgen/rlvhp.htm
--
----------------------------------------------------------------------
Satchi Venkataraman |Email:satchi@tresca.aero.ufl.edu
Structural and Multi-disciplinary |
Optimization Research Group |Fax: (352)-392-7303
Department of Aerospace Engineering,|Phone: (352)-392-6780
Mechanics and Engineering Science |
University of Florida |URL:
P.O. Box 116250 | http://www.aero.ufl.edu/~satchi
Gainesville, FL 32611-6250 |
----------------------------------------------------------------------
Lead, follow or get out of the way.
Subject: Re: Fighting Complexity
From: edmoore@vcd.hp.com (Ed Moore)
Date: 9 Nov 1996 01:14:28 GMT
Jonathan Priluck (jamcorp@world.std.com) wrote:
: In a nutshell, there seems to be a
: tendency on the part of almost everyone I'm managing and working with to
: move quickly past simple solutions in a hurry to try implementing more
: complex options.
One of my machine design professors would have marked them down for that.
: The more complex solutions are always explained to me as "better" in
: some way or antoher. In the case of this particular mold the complex
: solution will acheive "perfect" geometry. The imperfect geometry would have
: left our structure segments with a very slight oval cross section as opposed
: to a perfectly round one.
That sounds like going from from invention to final design without passing
through the prototype stage.
: I can't see anything seriously wrong with using a slightly oviod
: cross section if it makes the tooling simple to build (which it does). More
: importantly I want the simpler mold to be built and tested *before* we move
: forward with the much more complex geometry "needed" for a round section.
Yes, build a prototype.
: Needed is in quotes becuase the "problem" of mold release and ovoid cross
: section has yet to actually manifest itself in a pysical tool and becuase
: there is no indication that the oviod cross section is actually undesireable.
: The people doing the design are convinced that this problem exists
: and, with gusto, have attacked and solved it by complexification of the job.
Reminds me of when I was young. I loved stress analysis. I could
calculate what the stresses would be in a part. I had an older lead
engineer who often would show in minutes that the stresses were low
enough that we didn't care what they really were. It took a lot of
fun out of the job, but it saved an enormous amount of time.
: I'm not saying they design is wrong, only that it might be. I am
: definately not convinced the round section requires the complex solution,
: building the oval section mold would help us understand the problem better
: and it would be a useful tool.
Sounds like what a prototype should do.
: I can see the part in my "solid model" (in my mind) and there
: appears to be more than enough degrees of freedom for the mold to separate
: without damaging the parts. But that is not the real issue, and that's what
: I wanted to talk about in the first place. The real issue is that nobody
: seems to want to *try* the simple solution first. What I want to know is why
: that is?
In the nuclear power plant industry (1967-78) and aircraft industry (1978-82)
I did not find simplicity highly valued. In the inkjet printer business it
is absolutely prized. I think the difference is is that printers are a high
volume, low cost product. Adding several dollars to an aircraft component
meant nothing. In fact, it was a Good Thing to add money to remove weight.
Adding pennies to a component in high volume consumer products encounters
great resistance. Complexity costs money. Maybe you need to hire a
manufacturing engineer who has bled to save a penny. :-)
--
Ed Moore
Hewlett-Packard The keyboard is my employer's, but
Vancouver, WA, USA the keystrokes belong only to me.
Subject: Re: Cracks in chrome and steel cylinders
From: tsiporak@actcom.co.il (Israel Kehaty)
Date: Sat, 9 Nov 1996 01:23:13 GMT
In article <328047FB.5650@worldnet.att.net>,
woody.white@worldnet.att.net says...
>
>Don,
MIL-STD-866 is dealing with grinding and NDT testing for cracks as a
result of it.
>Perhaps fluorescent dye penetrant testing would work for you.
>_woody_
>
>DF Roell wrote:
>>
>> I am looking for a technique to quickly and easily identify hairline
>> fractures and cracks in large steel and chrome cylinders. ...snip...
>> ==========================================================
>> Don Roell 3M Company | Opinions expressed are mine and
>> 612 778 4445 (office)| are not to be construed as my
>> 612 778 6051 (fax)| employer's, so please treat them
>> dfroell@mmm.com (email)| accordingly
>> ==========================================================
>> 3M Center Bldg 99-2
>> St Paul, MN 55144-1000
>> ==========================================================
>
>--
>de Woody (WB4QXE) - woody.white@worldnet.att.net
>Electron Microscopist/Microanalysist,
>Ham radio "homebrewer", shade tree mechanic,
>'90 Nissan 240SX, wish still had my Mcycle too!
>http://www.geocities.com/capecanaveral/3722
>.
Subject: Re: Fighting Complexity
From: jamcorp@world.std.com (Jonathan Priluck)
Date: Sat, 9 Nov 1996 05:22:19 GMT
In article <560ltk$npi@news.vcd.hp.com>, Ed Moore wrote:
>Jonathan Priluck (jamcorp@world.std.com) wrote:
>
>: In a nutshell, there seems to be a
>: tendency on the part of almost everyone I'm managing and working with to
>: move quickly past simple solutions in a hurry to try implementing more
>: complex options.
>
>One of my machine design professors would have marked them down for that.
Hi Ed!
Hope life is treating you well :^). This professor, too bad there
are not thousands more like him :^(
>: solution will acheive "perfect" geometry. The imperfect geometry would have
>: left our structure segments with a very slight oval cross section as opposed
>: to a perfectly round one.
>
>That sounds like going from from invention to final design without passing
>through the prototype stage.
Exactly, this job it *is* a prototype. I keep telling everone over and over,
"it's a prototype, I don't mind if it does not work perfectly, even if it
does not work at all. I just want us to try it and see so we can learn more
about the technology we are dealing with". Everyone knows it's a prototype,
but still. In the end I quit fighting, I simply instructed them to build
the simpler mold and told them that I would not pay to have the more complex
mold built until someone has built the simpler first. They were not happy
about it but they know when it's time to stop talking and start cutting metal.
>: I can't see anything seriously wrong with using a slightly oviod
>: cross section if it makes the tooling simple to build (which it does). More
>: importantly I want the simpler mold to be built and tested *before* we move
>: forward with the much more complex geometry "needed" for a round section.
>
>Yes, build a prototype.
Hey, I've an idea! Maybe you can come and explain to them why we build
prototypes. O.K. maybe that's excessive but how about helping me to
articulate the same message. How woud you explain to a person who is
convinced that they don't need to build the prototype becuase they already
know the answer that maybe their analysis is not as foolproof a they think.
Here comes the hard part of the assignment. You have to explain it without
telling or even implying that they might be wrong. The reason for this is
that it's not worth the managerial problems it would create over the long
term. My solution (and I am not satisfied with my solution) was to instruct
them to do as I asked becuase it was I who needed to better understand why
they were right. That I needed to see for myself why the "inferior" mold
wouldn't work even if it was obvious to them, and that they were just going
to have to bear with me on this one. So far so good, I've been promised a
mold but it's now going to take a month instead of a week. Weird huh!
>Reminds me of when I was young. I loved stress analysis. I could
>calculate what the stresses would be in a part. I had an older lead
>engineer who often would show in minutes that the stresses were low
>enough that we didn't care what they really were. It took a lot of
>fun out of the job, but it saved an enormous amount of time.
In other words, is it relevant? That's such a difficult question to ask,
people always assume their questions are relevant. Of course most questions
are not relevant, some questions don't even really make sense they only
appear to becuase they have the proper gramatical form and can be asked.
>Sounds like what a prototype should do.
That's just it Ed, most engineers I work with these days just don't beleive in
prototypes.
>In the nuclear power plant industry (1967-78) and aircraft industry (1978-82)
>I did not find simplicity highly valued. In the inkjet printer business it
>is absolutely prized. I think the difference is is that printers are a high
>volume, low cost product.
Interesting. LBM is itself a high volume low cost item. Right now that's
not the case but that is the goal and it's not a matter of figuring out if
it can be done or not, it's simply a matter of making it so. At the same
time, the most important applications for LBM are in aviation and other
areas with similar ground rules. Will aviation people use a material that
is stronger and lighter if it also costs less? I half way suspect they will
not.
>Adding several dollars to an aircraft component
>meant nothing. In fact, it was a Good Thing to add money to remove weight.
>Adding pennies to a component in high volume consumer products encounters
>great resistance. Complexity costs money. Maybe you need to hire a
>manufacturing engineer who has bled to save a penny. :-)
I don't actually hire any engineers, I only work with the ones my
sucontractors have on their staffs. As a result I don't get to pick and
choose. Often I am working with a particular sub because of some other
importnat reason and the engineer is justsomething you have to deal with,
they come with the territory. Some are great, others mediocre, occasionally
they are such a problem that I am forced to find a new vendor to handle the
job. I'ts a balancing act.
Best Regards, Jon Priluck
>--
>Ed Moore
>Hewlett-Packard The keyboard is my employer's, but
>Vancouver, WA, USA the keystrokes belong only to me.
>
--
* Jonathan Aerospace Materials Corp., 37 Antwerp St. Brighton MA, 02135 *
* Tel (617) 783-4588, Internet: president@jamcorp.com *
* Developers and manufacturers of Lattice Block Materials ... *
* the world's strongest and lightest materials. *
Subject: Paper Scientist position
From: romuald@netcom.ca(romuald stanisla krzywanski)
Date: 9 Nov 1996 06:05:59 GMT
November 7, 1996
Employment Opportunity
POSITION TITLE: RESEARCH SCIENTIST - PAPER PHYSICS AND REFINING
Company: Canadian Forest Products Ltd.
Research & Development Centre
Vancouver, BC, Canada
Reports to: Vice President, Research & Development
PURPOSE:
The Research Scientist - Paper Physics and Refining is responsible for
conducting research work on fibrous raw materials, pulp and paper
properties, and the end uses of fibrous materials. Work on the
development of paper properties to meet requirements for specific paper
applications is also an essential function of this position.
MAJOR DUTIES:
Under the guidance of the Vice-President, Research & Development,
provide research and development in the field of pulp and paper
physics.
Specifically:
Prepare and prioritize research and development proposals consistent
with the division's goals and ensure the approved projects are carried
out in a timely and effective manner by establishing sound experimental
designs and effective working plans.
Prepare scientific and technical reports for internal or external
submission and ensure early alert to the patent potential of research
findings. Participate in the commercialization of new products and/or
implementation of new processes resulting from research and development
work.
Maintain an up-to-date knowledge of advances in the areas of pulp and
paper physics science and related technology.
QUALIFICATIONS:
Ph.D. degree in either Mechanical or Chemical Engineering. At least
three years experience in research and development in the areas of
paper
physics and refining.
Knowledge of wet - end chemistry would be an asset.
Must have excellent interpersonal, analytical and problem solving
skills
and be comfortable working in a team environment.
Experience with statistical analysis software packages.
Some experience working with microscopes, microtome and image analysis.
Permanent resident of Canada or Canadian citizen.
Interested applicants are invited to forward their letters of
application and resumes by Friday, December 6, 1996 to the attention of
Dr. S. Chow, Vice-President, Research & Development, c/o Ms. A. Sam,
Administrative Assistant at the following address or fax to (604)
264-6234 or e-mail to "asam@mail.canfor.ca"
Mailing address: Canfor Research & Development Centre, Suite 101 -
1750
West 75th Avenue, Vancouver, BC, V6P 6G2
Subject: Re: Fighting Complexity
From: rizzo@hogpb.ho.att.com (-A.RIZZO)
Date: 7 Nov 1996 15:47:05 GMT
In article ,
Jonathan Priluck wrote:
>
>Hello (good morning?),
>
> It's 4:00 am and I can't sleep because this new injection mold
>we're designing is driving me nuts. ...
>
[snip]
>
> ... The real issue is that nobody
>seems to want to *try* the simple solution first. What I want to know
>is why that is?
>
>Best Regards, Jon Priluck
Jonathan,
You seem to have a management problem on your hands. It would
appear that your designers are in extreme local optimization mode.
It might be useful to remind them that the objective is not to
have the best possible mold but to bring a good-quality product
to market as soon as possible?
You might also consider communicating with them by using Goldratt's
"cloud," also known as a conflict resolution diagram. I'll take a
stab at creating one for you. But you'll have to improve it, to
make it valid for them and for yourself.
(B your need) (D your want)
bring the product to accept a mold that makes
market quickly. slightly oval shapes.
(A objective)
have a financially
successful product.
(C their need) (D' their want)
have a good-quality have a mold that makes
product. circular shapes.
When you communicate with them, try to follow the script, below.
It's a good idea to role-play it with a neutral party first, even
if that neutral party is your own image in a mirror.
"First, do we agree that our common objective is to have a
financially successful product?"
They are very likely to agree with this statement. After all,
it's nothing more than mom and apple pie stuff. Reading the objective
to them lets the communication begin on a note of agreement, and
it avoids having them put up their defenses.
"We seem to have a slight conflict as to how to proceed. This
diagram is just a way of describing the conflict."
At this point you should read the conflict to them. Read their
side of the conflict first. This lets them see that you understand
their side of the issue. Again, it serves to keep their defenses down
and the communication link open.
"In order to have a financially successful product, we must have
a good-quality product. This is my understanding of the need that
you see. Is it correct?"
Give them a chance to respond and to modify their perceived
need at this point (C).
"In order to have a good-quality product, we must have a mold
that makes circular shapes."
Again, give them a chance to respond and to correct their side
of the cloud. Once they see that you understand their side of the
conflict, they'll be more willing to listen to your side. This is
when you read your side of the conflict.
"In order to have a financially successful product, we must
bring the product to market quickly. In order to bring the product
to market quickly, we must accept a mold that makes slightly
oval shapes."
Here's the tough part. Once they've agreed that the diagram
adequately describes the conflict, it's time for everyone
to surface their assumptions.
Be sure that you surface assumptions only between _your_ need
and _your_ want, i.e., between (B) and (D). You must let them
surface the assumptions between _their_ need and _their_ want, i.e.,
between (C) and (D'), or you will appear to be manipulating them.
You should surface your assumptions regarding the (B) to (D)
connection first. Do this by reading that segment of the cloud
again, and adding the word "because..."
"In order to have a financially successful product, we must
bring the product to market quickly. In order to bring the product
to market quickly, we must accept a mold that makes slightly
oval shapes, because...."
The because-statement is the assumption. Surface as many as you
can. Then ask them to do the same with their side of the cloud, so that
you can better understand their reasoning. But kill your desire to put
words in their mouths.
After they surface their assumptions, test them by reading their
side of the cloud followed by their because-statements. Read the
entire sequence for each of their assumptions (in order to have C we
must have D' because...).
If they're making a false assumption, this lets them identify
their mistake. But you absolutely must prevent yourself from trying
to convince them that one or more of their assumptions are wrong.
If they don't surface any assumptions that they see as false,
then tell them that you accept their desire to achieve circular shapes,
but that doing so causes a negative for you. State that negative,
and be sure to link it logically to their desire to achieve
circular shapes.
If they suggest an acceptable solution at this time, then jump
on it. If they don't suggest any solution, then maintain a strategic
silence. Do not suggest a solution that breaks the conflict on their
side. If you suggest such a solution now, they'll resist it. Instead,
just leave them with the knowledge that you accept their decision,
even if it causes a significant negative for you.
Good luck!
Tony Rizzo
Subject: Re: Egg drop mechanism
From: wdsoule@pacbell.net
Date: Sat, 09 Nov 1996 00:36:11 -0800
Chris Pollard wrote:
>
> mchalefla@worldnet.att.net (mchalefla@worldnet.att.net) wrote:
> : Who do you punks think that you are, criticizing me in such a way?
> : Perhaps it's because I am new to USENET that I have taken offense to the
> : replies to my simple query. Or perhaps it's because I take any
> : criticims of my own intelligence very seriously. However, if you wish
> : to preach to me the importance of doing this project on my own, then you
> : obviously do not wish to offer advice, which is all that I asked of you.
> : Did I ask for a sermon on the benefits of doing my homework myself? I
> : think not. Next time, don't waste your typing time or my reading time
> : for your useless and pointless comments.
> You have also forgotten that they MIGHT have been potential employers too.
> Be careful who you upset on this newsgroup. some people ar elooking for
> potential employees and may keep records of unemployables. As they say
> you never know who your next manager might be.
He also dosen't seem to get the fact that 'hot heads' that can't take people criticizing them
will probably not be very good engineers. Criticizm is an effective means to improve
your design, process, or life.
The first thing that came to my mind when I read his original post was to write back and
say "Do it yourself". If you didn't try to figure out a solution on your own and you asked for
an online solution, then shame on you. If you honestly sat down and couldn't think of any
solution and then came to the newsgroup to ask for help, you should have worded your question a
little different I think.
Just some input from an entry level design engineer.....
Later
Wayne
Subject: hot water trickle answer
From: "DANNY L. OAKES"
Date: Sat, 9 Nov 1996 01:41:41 -0500
You fellow engineers are really missing this one. I live in a 24 year
old mobile home. I have this problem about once or twice a year.
Turn the water off and the hot water heater off (just to prevent the
element burning up, just in case the system is siphoned empty by having
the faucet open). Then take apart the faucet from the top. When
you remove the stem part of the valve, you will find the screw that
normally holds the washer in place has come off and has fallen inside
the faucet. You can usually remove it with a pair of tweezers or stamp
tongs.
I have been meaning to put Locktite on mine for years; but, every place
that I have worked has only used the stronger versions of the thread
locking compound. I don't want this screw to stay there forever. I
want to be able to change the washer when it needs replacing.
Anyhow, I'm unemployed in Florida and I really need to find a job. I have
included the first page of my resume. If you can help, please do. I really
need to stay somewhat close to Florida because of my 77 year old Mom. Even
though I have been a job shopper since 1967, I really would like to have a
permanent job now. I really would prefer a job involving Mil-Stds, Mil-
Specs, and ANSI std because of my extensive job history in those areas.
My second choice would be in a professional engineering area where I could
begin as a junior engineer, if need be. I have read many standards related
to the design & construction industry, especially related to residential
construction.
RESUME
DANNY OAKES November 1996
======================================================================
9416 S.W. 101 Avenue PHONE: (352) 495-3371
Gainesville, FL 32608-5918 E-mail: afn50752@afn.org
POSITIONS: SENIOR MECHANICAL ENGINEER +----------------+
E/M PACKAGING DESIGNER / ENGINEER | Algor FEA |
ELECTRONICS PACKAGING ENGINEER | & |
STRESS / VIBRATION / THERMAL ANALYST | AutoCAD WHIZ |
MACHINE DESIGNER / ENGINEER +----------------+
SENIOR MECHANICAL & E/M DESIGNER
AVAILABILITY: IMMEDIATE RATE: Negotiable
EDUCATION: LICENSE:
B.S. in Mechanical Engineering Florida Registered
University of Florida Professional Engineer
Gainesville, Florida License No.: 37993
June 1980 Since 1987
EXPERIENCE SUMMARY:
Twenty-eight years experience in various phases of mechanical and E/M
design.
ANALYSES: Made stress (linear & non-linear), thermal, vibration, and
shock analyses using both hand calculations and personal computers of
structural assemblies, composites, E/M packages, and pressure vessels.
ELECTRONIC PACKAGING: Designed packaging of electronic, electro-
mechanical, and microwave assemblies, including: EMI, RFI, and Tempest
enclosures; racks and panels; heat sinks; wiring, cables,and harnesses;
power supplies. Laid out printed wiring boards (digital, analog, and
SMT) and flexible wiring.
MECHANICAL: Designed plastic, rubber, composite, sheet metal and
machined parts; weldments, structures, castings, cams and linkages; jigs
and fixtures, precision mechanisms Designed hydraulic and pneumatic
control systems. Specialize in tolerances and fits; and complex 3-D
geometry.
SOFTWARE: ALGOR FEA linear and non-linear; static and dynamic; beams,
random vibration; frequency response; buckling w/load stiffening; gaps
& cables; composites; steady state and transient heat transfer), TK
SOLVER, MATHCAD; AutoCAD Rel 9, 10, 11, & 12, WINDOWS 3.1, MS-DOS 5.0,
QUICKBASIC, AutoLISP, C and C++ PROGRAMMING, several word-processors,
spreadsheets, and data-bases. I own licensed copies of all software
mentioned above, except AutoCAD.
STANDARDS: Excellent working knowledge of DOD-D-1000, DOD-STD-100, ANSI
Y14.5M, ANSI Y32.2, ANSI Y14.15, and MIL-STD-454; as well as other
related Air Force, Army, and Navy Technical Manuals and Design Guides
& Handbooks.
PERSONAL:
Single, excellent health, 5' 9", 190 pounds. Hobbies include PC/MS-DOS
PC computer clubs and AutoCAD user groups. Military: U.S. Army, HD 69.
Thanks for any help !!!!
DanO
Subject: Re: Creativity Challenge
From: tap17@deltanet.com (Steve Gray)
Date: Sat, 09 Nov 1996 00:54:46 -0700
In article <32795BB9.7703@rust.net>, ericm@rust.net wrote:
> Being an engineer does have some hazards. Friends are always asking for
> problem solving help. I guess its kinda flattering. I'm stumped on
> this one though, and now my brain won't let go.
>
> I've got a couple of friends involved in medeival recreationist groups.
> They are trying to make chain mail armor by turning 12 ga. wire on a 1/4
> dia. rod. and then cutting the windings into individual links.
> Apparently, cutting the links with wire cutters leaves the ends of the
> links pinched, and they don't but up well. My first suggestion was a
> cut-off wheel on a Dremel Moto-Tool. The links they've showed me look
> good, but now they're complaining about going through wheels too fast.
>
> Anyone out there think they can come up with some creative solutions?
> In a flurry of brainstorming I did come up with one other possibility,
> but it seems far fetched. How about wire EDM? I know industrial
> systems are extremely precise, and thus extremely expensive. I know
> absolutely nothing about the process of EDM. Is it possible that if
> accuracy is not a concern, a poor man's system could be set up, or are
> the controls for voltage, current, and wire feed prohibitive. Like I
> said, a little far fetched, but what do you think? Any other ideas?
>
> Eric
It may or not be relevant but there is a series called "Electrical
Discharge Machining - Removing Metal by Spark Erosion" in Home Shop
Machining. This is a 5-part series describing how to build an EDM machine
which might do the job. As a former EE used to complex circuits, I think
this project looks very lengthy and formidable, especially since you don't
know in advance how well it would work. Anyway the articles are in these
issues: May/June 1995, July/August, Sept/Oct, Nov/Dec, and Jan/Feb 1996.
The author is Robert P. Langlois, 295 Hetty St., Port Stanley ON Canada
N5L 1C1. You can reach HSM at Village Press INc., 2779 Aero Park Drive,
Traverse City MI 49685, 616-946-3712.
I doubt that the EDM will be a practical solution. My first attempt
would be to take the wound mandrel and slice through it lengthwise on a
milling machine using either a small diameter end mill (prone to breakage,
and slow) or a slitting or slotting saw. This would require a careful
setup for holding the mandrel, probably in a vise which clamped down on
each turn. This is relatively simple.
Another possiblity would use a bandsaw with a bimetal blade, with a
special holder to hold the mandrel vertically and guide it into the blade,
while at the same time having a well-fitting slot to constrain the bandsaw
blade so it doesn't wander. This could result in a rapid cut maybe .03
wide and, I think, is almost guaranteed to work if the setup is done
carefully enough. The mandrel could be at least 6" long, giving about
70-80 links at a time. The hard part would be building the jig; machining
skills and tools would be necessary unless it were made out of hardwood,
which also has a good chance of working. But someone with good shop skills
is needed. The links will probably need deburring before further use,
either by maching or by hand if desperate enough.
If you or they use any of these suggestions I would greatly appreciate
finding out what happens (by e-mail please). Good luck.
--
Steve Gray
Gray Associates
Santa Monica CA
Algorithms, computer graphics
Mechanical inventions
Subject: Re: Egg drop mechanism
From: tap17@deltanet.com (Steve Gray)
Date: Sat, 09 Nov 1996 01:09:22 -0700
In article <3282B987.6846@worldnet.att.net>, mchalefla@worldnet.att.net wrote:
> Does anyone have any idea how I can build a device, whose volume is less
> than 400 cubic cm, which can carry an egg through a 10 meter fall, and
> land on concrete without breaking the egg? Additionally, the lower the
> mass of the device, the better.
>
> Thanks,
> Kevin McHale
Sounds like one of those MIT student challenges. Fine. I would build a
steel box as big as possible under the space limitation (about 2x3x4
inches). Line the inside of the box with maybe 3/8 inch closed-cell foam.
Put the egg in and fill up the rest with a fluid having the same density
as the egg (water?) and put the lid on and attach strongly.
The foam gives the inside volume some room to decrease when the box
gets slightly deformed. The fluid is supposed to prevent force from acting
on the eggshell (that is, the egg has no reason to rise or fall or move).
Please post results of any idea you use so the rest of us can learn too.
--
Steve Gray
Gray Associates
Santa Monica CA
Algorithms, computer graphics
Mechanical inventions
Subject: Re: Soda fizz
From: tap17@deltanet.com (Steve Gray)
Date: Sat, 09 Nov 1996 01:12:12 -0700
In article <19961108115100.GAA22509@ladder01.news.aol.com>,
klwasson@aol.com wrote:
> > Subject: Soda fizz
> >From: handreas@msmail4.hac.com (Andreas, Harry A)
> >Date: 1 Nov 1996 22:58:42 GMT
> >Message-ID:
> >
> >Everyone knows that if you pour soda [that's pop for you mid-westerners]
> into a glass it fizzes up for a while [beer, too].
> >But after the foam goes away, if you pour some more in, it rarely fizzes
> up again, or at least not much.
> >This bugged me for some time because I don't like really fizzy drinks and
> I try to get rid of most of the fizz.
> >I believe that I know the answer as to why it will not fizz up much the
> second time around, but was surprised to find that most, nay, all, of my
> engineering colleagues could not come up with the answer.
> >So send me an e-mail if you know, or think you know, or don't give a rats
> ass and just want the answer.
> >
> >Harry
>
> Here is a related phenomenon. Take a half-full bottle of beer and slam it
> real hard on its top by the bottom of a second bottle of beer, so hard
> that you almost think you might crack the glass. The beer will foam up so
> much it will overflow the top, much more so than if you had shook the
> bottle of beer for ten minutes. Why?
I, for one, give about 0.5 of a rat's ass, so please post the answer or at
least some of the less preposterous hypotheses.
--
Steve Gray
Gray Associates
Santa Monica CA
Algorithms, computer graphics
Mechanical inventions
Subject: Re: Pipe Section Modulus
From: jouko@megaweb.co.za (Jouko Tolonen)
Date: Sat, 09 Nov 1996 03:49:20 GMT
Al & Sue O'Neill wrote:
>Shane Mason wrote:
>>
>> Does anyone out there know the formula to derive the section modulus
>> for pipe? At work, all our benders are rated at section modulus, say
>> 3.5, for schedule 80 steel pipe. Our problem is we deal with a lot of
>> stainless steel, some schedule 160, some T11, T91, etc. and don't know
>> what the section modulus for those are.
>>
>> Any help would be greatly appreciated.
>>
>> Shane
>I= (pi/64)* (Do^4 - Di^4) = inches^4
>S= I/c = inches ^3
>c= Do/2 or distance to extreme fibre
I found I shareware program on the net which may be helpfull for the
original author of the question:
"
NPS (Nominal Pipe Size) version 2.0 for DOS (look for PIPE2.ZIP
or PIPE2.EXE on your favorite BBS) -
NPS is an easy to use database of dimensional, weight and
flow
information for more than 2500 sizes of standard and
specialty
pipes and tubes (from 1/8" to 72" nominal size) in over 25
different materials, including metals, plastics and
composites.
The data can be displayed in US, Imperial or metric units.
Program defaults are fully user configurable.
"
Jouko
jouko@megaweb.co.za
South Africa
Subject: Re: Just try this, it will work
From: ramsol@NetVision.net.il
Date: Sat, 09 Nov 96 13:06:45 PDT
In Article<55hap5$f7@ringer.cs.utsa.edu>, write:
> Path: news.NetVision.net.il!news-dc.gsl.net!news.gsl.net!news-lond.gsl.net!news.gsl.net!news-peer.gsl.net!news.gsl.net!swrinde!ringer.cs.utsa.edu!runner!rknight
> From: rknight@runner.utsa.edu (Richard Yael Knight)
> Newsgroups: alt.telescopes.meade.lx200,comp.software.measurement,alt.music.meat-loaf,fj.engr.mech,sci.engr.mech,rec.games.mecha,alt.games.mechwarrior2,alt.politics.media,fj.soc.media,alt.internet.media-coverage,ba.internet.media-coverage,fj.net.media.ethernet,finet.freenet.mediateekki.yle.radio.
mafia,alt.image.medical,fj.sci.medical,fj.soc.medical,misc.education.medical,relcom.commerce.medicine,talk.politics.medicine,de.soc.medien,soc.genealogy.medieval,soc.history.medieval,maus.sci.medizin,de.alt.megatest
> Subject: Re: Just try this, it will work
> Date: 3 Nov 1996 05:32:21 GMT
> Organization: The University of Texas at San Antonio
> Lines: 11
> Message-ID: <55hap5$f7@ringer.cs.utsa.edu>
> NNTP-Posting-Host: runner.jpl.utsa.edu
> Xref: news.NetVision.net.il alt.telescopes.meade.lx200:1351 comp.software.measurement:468 alt.music.meat-loaf:219 fj.engr.mech:57 sci.engr.mech:6081 rec.games.mecha:21060 alt.games.mechwarrior2:11069 alt.politics.media:8695 fj.soc.media:308 alt.internet.media-coverage:4142 fj.net.media.ethernet:
37 alt.image.medical:901 fj.sci.medical:876 misc.education.medical:6756 relcom.commerce.medicine:8650 talk.politics.medicine:12711 de.soc.medien:647 soc.genealogy.medieval:3679 soc.history.medieval:7934 de.alt.megatest:122
>
> Followup-To: alt.telescopes.meade.lx200,comp.software.measurement,alt.music.meat-loaf,fj.engr.mech,sci.engr.mech,rec.games.mecha,alt.games.mechwarrior2,alt.politics.media,fj.soc.media,alt.internet.media-coverage,ba.internet.media-coverage,fj.net.media.ethernet,finet.freenet.mediateekki.yle.radio
mafia,alt.image.medical,fj.sci.medical,fj.soc.medical,misc.education.medical,relcom.commerce.medicine,talk.politics.medicine,de.soc.medien,soc.genealogy.medieval,soc.history.medieval,maus.sci.medizin,de.alt.megates
> t
> References: <267.654193326831@news.nemonet.com>
> Organization: The University of Texas at San Antonio
> Distribution: world
> X-Newsreader: TIN [version 1.2 PL2]
>
>
> Well, another person "killed!" Those people using low-tech readers
> might want to switch to tin or another one with a kill file that's easy to
use.
> -Richard
Just interested: are you Richard or Yael?