Newsgroup sci.engr.mech 28371

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Hi,
Does anybody know a computer-aided method to estimate fabrication costs
of welded steel structures?
Erkki Niemi
Lappeenranta University of Technology
Finland

I am searching for a programm for COST ESTIMATING (CAPP) in a
mechanical workshop (milling, grinding etc.)
Does anyone know such a programm????
Also reply by email:   H.J.M.Laurijsen@nl.cis.philips.com
Thank you!

>It's just because they are simple that they are bypassed. Almost everyone 
>likes to try-out the more complex model first. If it doesn't work they may 
>get back to the simple model later. I agree this all wastes time and money.
>
>How do you break that?.
My solution is just to refuse to pay for a complex prototype if there is a
simpler model that has not yet been tried.  If it has been tried and does
not work then fine, but it has to be tried first.  Our team has a lot of
diverse talents and so they are very creative, the difficult part is to 
harnessing the creativity, but only *when it is needed*.  The other tough
part, and I keep sliding it in as an issue, is to bear in mind that the team
is more important than any particular project we might be working on at the
time.  So a lot of this is a management issue, how to embrace simplicity and
still keep everyone happy and productive. 
>One way you could try it is to set up three teams of designers. 
This is actually a great idea, I'm going to archive this posting so that I
can try this out when the company is larger than it is today.  Right now we
do not have three teams :^)  We have one team, and it's taken a lot of work
to make them into one team, and they are very effective.  But I beleive in
competition and I like the way your story works out in the end, the
competition forges all three teams into a single team.  A process that on
first glance might  appear divisive ends up bringing the three teams
together.  I'm going to think about this for a while, I sense there is a lot
I can learn from this anecdote of yours, thanks.
>They each 
>come up with a design and a method for implementing it and rough budget 
>costings. Each team presents their design and the other two have to find 
>fault with it. The design that wins out is the one with the least problems 
>and least cost. The one who goes first is the one with the lowest bid 
>costings. Costings have to be revised up for each problem that is found. If 
>you find that another team, presenting before you do, has had the same idea 
>as yours you still have to pick the holes in it. Then choose another idea.
>One last item. Set a very tight time limit (hours not days) so that they 
>don't get too long to think.
Aha!  A very important point, not only does it keep designs from spinning
out of control but it also keeps the game light and freindly.  By only
allowing a few hours people cannot get overly invested in their designs and
hence a lot of the more difficult aspects of human nature never get a chance
to develop.  I think keeping the time frame short is a very important
detail.  If you gave the teams even a week to work on their designs the
competition would become devisive as teams became ego invested in their
designs.  
>It's a good game and may just get them to think differently about their 
>design chooice methods.
I'm going to try this out if I can.  I'll let you know how it goes.  I
probably won't get a a chance to try it out on this project but the next one
should be coming along soon.
>I have been in only one place where this practice went on for one project. We 
>ended with a really elegant and simple design that really was very cost 
>effective. Which of the three designs did we eventually select?. .. None of 
>them. In the process of shredding the other teams ideas we all began to 
>realise that all the original design ideas had problems and in resolving 
>answers to each of those we found a totally new solution that none of the 
>teams had come up with.
This is the part that really makes the practice interesting from a good
management standpoint.  As you've noted, the final design was better than
any of the origionals.  But equally important the exercise ends up expanding
lines of communication, builds up respect, and helps make the players on all
three teams more a more potent and cohesive unit. 
Best Regards, Jon Priluck
-- 
*   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.              *

>It's just because they are simple that they are bypassed. Almost everyone 
>likes to try-out the more complex model first. If it doesn't work they may 
>get back to the simple model later. I agree this all wastes time and money.
>
>How do you break that?.
My solution is just to refuse to pay for a complex prototype if there is a
simpler model that has not yet been tried.  If it has been tried and does
not work then fine, but it has to be tried first.  Our team has a lot of
diverse talents and so they are very creative, the difficult part is to 
harnessing the creativity, but only *when it is needed*.  The other tough
part, and I keep sliding it in as an issue, is to bear in mind that the team
is more important than any particular project we might be working on at the
time.  So a lot of this is a management issue, how to embrace simplicity and
still keep everyone happy and productive. 
>One way you could try it is to set up three teams of designers. 
This is actually a great idea, I'm going to archive this posting so that I
can try this out when the company is larger than it is today.  Right now we
do not have three teams :^)  We have one team, and it's taken a lot of work
to make them into one team, and they are very effective.  But I beleive in
competition and I like the way your story works out in the end, the
competition forges all three teams into a single team.  A process that on
first glance might  appear divisive ends up bringing the three teams
together.  I'm going to think about this for a while, I sense there is a lot
I can learn from this anecdote of yours, thanks.
>They each 
>come up with a design and a method for implementing it and rough budget 
>costings. Each team presents their design and the other two have to find 
>fault with it. The design that wins out is the one with the least problems 
>and least cost. The one who goes first is the one with the lowest bid 
>costings. Costings have to be revised up for each problem that is found. If 
>you find that another team, presenting before you do, has had the same idea 
>as yours you still have to pick the holes in it. Then choose another idea.
>One last item. Set a very tight time limit (hours not days) so that they 
>don't get too long to think.
Aha!  A very important point, not only does it keep designs from spinning
out of control but it also keeps the game light and freindly.  By only
allowing a few hours people cannot get overly invested in their designs and
hence a lot of the more difficult aspects of human nature never get a chance
to develop.  I think keeping the time frame short is a very important
detail.  If you gave the teams even a week to work on their designs the
competition would become devisive as teams became ego invested in their
designs.  
>It's a good game and may just get them to think differently about their 
>design chooice methods.
I'm going to try this out if I can.  I'll let you know how it goes.  I
probably won't get a a chance to try it out on this project but the next one
should be coming along soon.
>I have been in only one place where this practice went on for one project. We 
>ended with a really elegant and simple design that really was very cost 
>effective. Which of the three designs did we eventually select?. .. None of 
>them. In the process of shredding the other teams ideas we all began to 
>realise that all the original design ideas had problems and in resolving 
>answers to each of those we found a totally new solution that none of the 
>teams had come up with.
This is the part that really makes the practice interesting from a good
management standpoint.  As you've noted, the final design was better than
any of the origionals.  But equally important the exercise ends up expanding
lines of communication, builds up respect, and helps make the players on all
three teams more a more potent and cohesive unit. 
Best Regards, Jon Priluck
-- 
*   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.              *

On Mon, 04 Nov 1996 13:22:02 +1100, wmcbride@mail.newcastle.edu.au
(Bill McBride) wrote:
>Although this is not really the place it's worth a try.
>
>The mazda rotary engines (8,10,12,13's)  Does anybody know there weights,
>powers and physical dims.  Close ballparks are fine.  Also what about the
>1.8l subaro (sp?) boxer engine.
>
>Im after a high power to weight ration engine with between 70-100 hp for a
>hovercraft.  The engine is to operate at constant speed so that the torque
>curve doesnt matter (re rotary).  
>
>Thanks
>
>Bill
In that case how about a motorbike 2-stroke?
--
Dave Howell
davidh@trutest.co.nz    "Basic research is what I am doing when I
R&D; Engineer             do not know what I am doing" - Von Braun
Tru-Test Ltd, Auckland, N.Z.

The  EPA requires that techs servicing A/C, heat pumps, refrigerators,
and car AC be certified and without the certification you can buy the
R-22, reclaimed R-12, new blends, or any other CFC or HCFC
refrigerant.  Free Traing on line or down-loand the training manual.
Exam available on line at epatest.com  rpa@mainstream-engr.com

JG>I am looking for static and kinetic coefficients of friction for
JG>automotive/truck tires on dry, wet, and dirty roadways.
Jason,
Here are some typical values:
    Coefficients of Friction
    ---------------------------
    Ice with water on top                           0.15 to 0.2
    Worn asphalt, concrete or epoxy floor           0.55 and up
    worn concrete                                   0.65
    new asphalt or concrete                         0.75
    asphalt or concrete inc. clamshells             0.85
    scarified concrete                              0.95
------------------------------------------------------------------
Bill Weitze, PE:
Co-Sysop, The Engineers' Club BBS, (408) 265-3353, San Jose, CA
Executive Committee Member, ASME Santa Clara Valley
Senior Engineer, GE Nuclear Energy
bill.weitze@engineers.com                       opinions are mine
------------------------------------------------------------------
 * OLX 2.2 * Member, American Society of Mechanical Engineers.

Pedro D. Peralta wrote:
> 
>                Hi there!
> 
>                My group here at Los Alamos National Lab is trying to get into
>    a small EDM, preferably something that can fit in top of a bench and that
>    can do straight cuts with decent precision. I have talked to the people
>    of Brother and Charmilles, and they do not seem to have anything like
>    that (they have good machines, but they are kind of too big for what
>    we have in mind). Does anyboby out there know if such "bench" EDM's
>    exist? Any pointers would be greatly appreciated.
> 
>                   Thanks,
> 
>                                                 Pedro D. Peralta
> -----------------------------------------------------------------------------
>  pperalta@lanl.gov                              Los Alamos National Lab
>  Phone: (505) 665-3289                          Center for Materials Science
>  Fax: (505) 665-2992                            MS K765
>                                                 Los Alamos, NM 87545
Do you want to use this for TEM, STEM or SEM sample prep?

In article <3282B987.6846@worldnet.att.net>,
"mchalefla@worldnet.att.net"  writes
>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
I've seen no insult to your intelligence from this group; nor would I
expect any.  For my own part requests for help have been very wisely and
helpfully dealt with.
You address your question as if you yourself have no ideas; since you do
not suggest problems or potential solutions.  I personally saw your
first posting and assumed "he cannt be bothered to think".  That may not
have been your intention but it clearly came across that way to many
others. Yet again there is much to be learnt in the "art" of
communication.
-- 
John Lloyd

rizzo@hogpb.ho.att.com (-A.RIZZO) wrote:
>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?
Snip #2
>     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..."
snip again
>Tony Rizzo
Just a thought. Please make sure that you examine your own assumptions
as well (and Importantly, let them challenge your assumption). Don't
leave yourself (as the Manager) out of the refining process. Find out
why they think that a slightly ovaloid (sp?) part is no good. It is
still posible that it is no good, and a circular one is required. They
seem to think it is. Someone is wrong, and if you are not prepared to
have it be you, you are not prepared t start asking them to change
their assumptions.
In other words, it is important not to dictate from on high. Let them
into the process of making the product commercially viable, not just
on the level of achieving a specific problem.
  ########## Paul van den Bergen
####       # c/- Materials Eng., Monash University
#  ####    # Clayton VIC 3168 Australia
####  #    # pavan1@student.monash.edu.au
  #   ###### ph.  +613 9905 3597
  #   #      fax. +613 9905 4940
  #####      meow *cough* feathers
I feel it is my duty to warn everyone that there is an
international consortium of powerful people who get   
together and facilitate the distribution of conspiracy
theories in order to keep the minds of the masses off 
the real issues that are affecting the world (whatever
they may be...)

I'm writing this request on behalf of a, yet, small company, 
manufacturers of
light machinery. I'm not very much into machinery myself, so please have 
me
excused if technical terms are inaccurate.
They are looking for the best bearing solution for a newly developed 
device. Plan on a
large scale production, and want advices on optimising price/performance 
relationship.
BEARING DESCRIPTION:
On the proto-type there have been used stainless steel 6003 2RS 
bearings, which have
been found to serve the *purpose* good, but a little costy.
        They will run in tap water, low level of particles.
        Radial force max 10-15 kgs.(20-30 pounds)
        Axial force max 3-4 kgs.(6-8 pounds)
        Forces may vary from 0 to max every second (not very "impact".).
        Running time averages only 5-10 mins/ day.
        50-150 RPM
        Drive force is low, so not very much static friction allowed.
1. They would like know if anyone can recommend any *alternative*, 
cost-effective
bearing types???
        (New materials/solutions welcome.)
2. A recommendation and/or qoute, price/bearing "can" be posted to me.
        Or I may put you in contact with the right persons, for more 
details.
        Amount: Need for first series will be approx. 20 000 pc 
bearings.
Please mail me at:         smedhaug@sn.no
Regards,
- Svein Medhaug
-- 
- Svein Medhaug

>From: DC, 75277.3335@CompuServe.COM
>>What completes the grounding circuit in an electrical system?
>Let's say a refrigerator shorts and the current goes to ground (thus
>protecting anyone touching the refrigerator).
>The current goes through a wire down to metal pipe down to the earth
>itself, but how does it come back from the soil in the back or front
>yard to complete the circuit to the refrigerator in the house?
>Thanks for help and info.
In theory, the current diverted to the ground of the refrigerator will be
sufficient to blow the fuse or trip the circuit breaker in the hot leg of
the circuit, thus 'protecting' the user from electrical shock.  In this
example, the ground current would re-enter the house neutral at the main
circuit-breaker panel.  This is where (at least in U.S. systems), the
neutral bussbar of a 3-wire system is electrically bonded to the grounded
conductors of the individual circuits.  These grounds take the form of a
third conductor in the case of non-metallic cable or the conductive
surface of the electrical conduit itself (depending on your code
requirments).  The main-circuit breaker panel is often where the system
ground is electrically connected to an external grounding rod, or a
cold-water pipe.
The problem, as you might imagine, is when for some reason, say defective
wiring, you have a high resistance ground connection.   In this case, the
protective overcurrent device will not trip, leaving the circuit hot and
the frame of the device at an energized, possibly dangerous potential. 
If you suspect that you have a high resistance ground, your installation
should be immediately checked by a qualified electrician.

Winfried wrote:
> 
> Does anyone have experiences with Cat gas engines (preferably the 3516's).
> I'd like to know some known problems since we're planning a new cogeneration
> plant and Caterpillar is one of the potential contractors..
> 
> Thanks..
> 
>         Winfried.
Talk to someone at Royal Dutch / Shell Group.  I think that Cat has supplied 
some of these to Shell Oil USA for use on offshore platforms.  The use the 
gas from the oil wells to fuel them.  
-matt

hobdbcgv@aol.com wrote:
> 
>    I have several books that use the symbol Z for elastic section modulus
> and several that use the symbol S for elastic section modulus. I would be
> careful about assuming there is a standard nomenclature.  The concept of
> plastic section modulus is specious at best, anyway.  Some authors hold it
> exists, but all things in books are not necessarily true.
>    I also have seen the symbol Z used as "plastic section modulus" in some
> of those, although the machinations used to derive it make the term more
> of a bastardization of the geometric concept.
>    Having personally determined plastic failure points for equation
> determination, I would caution that in plastic ranges the geometry changes
> with material (re: the "necking" of specimens, and see the very definition
> of plastic) and thus a section modulus changes with time for a given
> ductile specimen, making section moduli a material-dependent concept
> rather than a purely geometric concept. This presents a problem in most
> equations for capacity which relate independent mathematically derived
> geometric parameters (such as section moduli) to independent test derived
> material parameters (such as yield strength) to approximated
> mathematically derived load parameters in order to determine probablility
> of failure (such as safety factor).
> 
I would refer you to the latest edition of the American Institue of Steel 
Construction (AISC)  "Manual of Steel Construction" which contains both the 
"Load and Resistance Factor Design Specification for Structural Steel 
Buildings" and the "Code of Standard Practice for Steel Buildings and 
Bridges" as an appropriate standard for the use of terminology on plastic and 
elastic section moduli.  I would estimate that more tons of steel structure 
are designed and built to this standard than to most others combined.  In 
this specification, one of the most commonly used limit states is the plastic 
bending strength based on the plastic section modulus.
Just as the elastic section modulus assumes a linearly elastic material when 
applied to actual materials, the plastic section modulus assumes ideal 
plasticity to infinite strains when applied to the bending problem.  However, 
both are purely theoretical geometric properties of a given section because 
they can be found by purely geometrical considerations.
Recall that all allowable or ultimate strength estimations are just that...
estimates or reference states.  Use of allowable stress formulae cannot take 
into consideration stress concentrations and residual stresses nor can all 
sections exibit ideal placticity to infinite levels of strain.  Just as many 
sections cannot reach strain levels high enough to produce their full plastic 
strength, many sections cannot even reach their initial yield strength before 
local or overall buckling limit states are reached.
Another thing to note is that the use of the term safety factor is rapidly 
becoming out of date.  The lastest probabilistic studies and the LRFD 
Specification mentioned above use overload factors applied to the design 
loads and reduction factors applied to member design strengths.  The benefit 
is that by calculating ultimate strengths, a better understanding of which 
failure mode(or limit state) will govern is obtained.  With allowable stress 
designs one is not always certain what will happen once the allowables are 
exceeded. However, the probability is much greater that these unfactored 
design loads will be exceeded than will be the factored ones which are used 
in limit states design. Furthermore, if the factored loads are exceeded the 
designer will have a better estimate of the response of the structure in 
terms of its ultimate strength and deflection, thus leading to safer and more 
uniform designs. 
-matt

Mr. Ek Charanyananda wrote:
> 
> Marvin Tulberg (marvin_tulberg@rl.gov) wrote:
> : I am looking for some technical help for a situation we are facing
> : regarding work on tank ventilation systems which may contain flammable
> : atmospheres.  We are monitoring the space for LFL (keeping below 25% of
> : lower flammability limits), but restrictions placed on us require that
> : any work in the air space can not cause a temperature exceeding 320
> : degrees F and can't cause any sparking (either by friction or by static
> : electricity).  We need to cut a 20" header which is made of stainless
> : steel (about 1/8" thickness).  We will also cut some carbon steel pipes
> : of schedule 40 from 1" up to 8" in these same conditions.  Note that
> : these cuts will be performed in a trench with limited access.
> 
> : We are running out of ideas.  It seems that any standard cutting method
> : (i.e. using saws, machining cutters, TORCHES, grinding wheels) could
> : either exceed 320 degrees at the cut or cause a spark.  I would
> : appreciate information from anyone who has access to new technologies
> : (or old) that could work in these conditions.
> 
> : Thanks!!!!
> 
> I can think of a method, but it is up to you to get the equipment
> involved.  You can use high-pressure water jet (with or without abrasive
> slurry) for the cutting.  Any frictional effect will be cooled by the
> cutting liquid.
> 
>                                                 -Ek-
There are cold cutters for pipe of all sizes made by the RIGID company.
RIGID makes pipe wrenches etc.  You have probably seen their catalog with 
pics of girls holding pipe wrenches inside your plumber's tool box.
The cutters look like big C-clamps with small pizza-cutter-like wheels that 
contact the pipe.  The operation is simple: You clamp the pipe then twist the 
cutter around, cutting the pipe a bit.  Then you turn the clamp a little, 
pushing the pizza wheels down into the cut a little deeper, and twist it 
around the pipe again, etc.,etc.  I have seen them used on at least 12" 
diamter pipe before, and I am sure that they go op to 20".

Try to contact SKF in Norway. They can probably help you. You might be
locking for some type of plain bearing and not a rolling bearing.
Stefan Norberg

thad kimo wrote:
> 
> i am writing a term paper for my material science engineering class and
> need information (books, articles, & websites)on precipitation-hardened
> stainless steels which protect flight deck recorders from various
> elements.  i need to know its durability, how it is tempered, & what
> other possible alternatives are for these recorders.  submission of
> references would be greatly appreciated.
> 
> thanx
> k
Try the American Society for Testing and Materials (ASTM). I know of one spec 
for precipitation-hardened stanless steel is ASTM A747 (just like the plane) 
but I think this spec is for castings.  You are probably interested in sheet 
or plate.  Look in the ASTM index.  Another place to look is the Ameican 
Society of Metals (ASM) "Metals Handbook". 
-mc

I am looking for simple HVAC graphics of ductwork, package units,
chillers, boilers, valves, dampers, etc. for simple sketching of HVAC
systems.  Can anyone suggest a download site for these types of
graphics?  Thanks.

DC <75277.3335@CompuServe.COM> writes:
}Why doesn't a person electrocute himself when he turns on the 
}ignition in a car, since he is holding a metal key contacting metal 
}leads (to the battery) in the steering column, and moreover his body
}is touching the car's ground (its frame)?
Because your assertion is false - the leads aren't connected to the
battery; they're connected to the starter solenoid (relay).  And
even if they were connected to the battery, +12VDC isn't going to
kill anyone directly.  The resistance of the epidermis is so high
that even if you spread your hand across both leads of the battery,
you wouldn't even feel anything, as the current flow (which is what
*really* matters in terms of fatality) is miniscule.  This is the
same reason why you can feel free to drape your finger across both
leads of a +9VDC battery (the small, rectangular ones) and not feel
anything, but if you touch it to your tongue, you'll feel a minor
twinge, as the liquid in your mouth is much less resistive than your
skin, and therefore allows a higher current flow.  Current is
proportional to voltage over resistance.
Jeff
-- 
Jeffrey S. Curtis                      | Internetwork Manager
Argonne National Laboratory            | Email: curtis@anl.gov
9700 South Cass Avenue, ECT-221        | Voice: 630/252-1789
Argonne, IL 60439                      | Fax:   630/252-9689

ASME used to have a discussion group on pressure vessels and piping in
the ASMENET. Since ASME stopped their own network and are now on
internet, I cannot find this discussion group. Would anybody know
where I can find it ?
Magued

In article ,
Jonathan Priluck  wrote:
>
>	I really appreciate your help... but...
Jonathan,
Forgive my naivete.  I could sense that the situation
was more complex than your initial request for help
suggested.  I took a chance anyway.  Clearly, your
proximity to the problem and the long history that you
have with your team provide you with much more information
than any outsider can have.  I'm sure that you'll lead the 
team to a favorable outcome.
Tony

Paschenbrenn@simplot.com (Paul Aschenbrenner) wrote:
>Sorry! I hit the wrong key and cut myself off.
>speed 30 mph coef dry= .62 wet .36
>speed 40                          .60       .33
>speed  50                         .58        .31
>             60                         .56       .30
>             70                          .55      .29
These are really minimal numbers for today's tires.  300 ft diameter
skidpad numbers (==>~40 mph) range from about .6g to about 1.0g for modern
cars in the dry.  Braking numbers for well designed cars yield similar
numbers.
Mark Folsom, P.E.
Consulting Mechanical Engineer

DC wrote:
> 
> Why doesn't a person electrocute himself when he turns on the
> ignition in a car, since he is holding a metal key contacting metal
> leads (to the battery) in the steering column, and moreover his body
> is touching the car's ground (its frame)?
> Thanks for clarifying this.
> 
> --
> From 75277.3335 at CompuServe
Well DC, it's a long story but suffice it to say that:
1)  Even if the ignition key were in contact with the 12 volt system in 
the car (and it isn't) there is not enough voltage there to "electrocute" 
a person.
2)  The normal resistance of the skin on your hands is sufficient to 
protect your body against shock up to somewhere around fifty volts, 
assuming that your hands are dry.  Not that you couldn't feel the current 
at fifty volts, but under "normal" conditions that is not enough voltage 
to "push" the current through your system.  You might want to take a look 
at an article I wrote on electrical stuff on my website.  Look for 
"Electrical" which has the link you should read.
Bob
-- 
http://www.MisterFixit.com
..

Dave wrote:
> 
> Treat your Al parts with an Alodine solution.
> Ask someone in aircraft the tech details.
> It's used whenever anodizing is not time/cost effective during the
>         manufacture of small detail parts.
> 
> Dave
Right. Alodine is a brand name for Mil-C-5541 chromate conversion 
coating. The mil spec gives a lot of the tech details.
-- Ted Mooney
------------
Visit 'the home page of the finishing industry'
http://www.finishing.com
------------

	I did a project similar to that in high school.  We had to build a 
device under 15 lbs to get an egg over a 5 ft wall on without breaking.  We got 
points for clearing the wall, points if it didn't break, and points for each ft 
beyond the wall it went.  
	Everyone in the class did sometype of catapult except me and my friend. 
 Instead we used a model rocket.  Sure the egg broke, but we still got like 5 
times as many points as any other group just because of the distance.
	We had 2 weeks to complete it, and got 2 class periods a week to work 
on it.  We finished ours and tested it the same night it was assigned, so 
during the class work times, we would just sit around and bs while the rest of 
the class was hard at work.  We never let on that we were finished, or told 
what it was, so everyone was convinced we would loose.
	Maybe you will be able to find some sort of loophole in the rules.  
Thats pretty much what engineers do.
Good luck,
	Jman

In article <3283C2EA.3C38@cc.umanitoba.ca>, Doug Krokosz  says:
>
>We're currently working on a small design project to warm diesal fuel
>via a heat exchanger utilzing some other-wise wasted heat.
>
>My problem is I am not a chemist or an expert in combustion and have
>conflicting data as to the optimum temp. the deisal should be before it
>goes to the engine.
>
>What is this ideal temp in the opinion of the experts of the world?
>
>Thank you so much.
>-- 
>****************************************************
>*       Doug Krokosz
>*       Mechanical Engineering
>*       University of Manitoba
>*       umkroko0@cc.umanitoba.ca
	The fuel needs to be comfortably above the wax formation 
temperature but otherwise as cool as possible so that the injectors see 
the density for which they were designed.

To whom ever wrote that the term draftsMEN was not correct.  GET A LIFE!  
When the word men/man is used in a word it is generic and means mankind.  
And a female boss has a problem with it she has too much time on her 
hands.  Also that same feMALE boss probably would not liked being 
referred to as feMALE/woMEN.  As I said before GET A LIFE! 
On Sat, 9 Nov 
1996, Jim Weir wrote:
> Peter  shared these priceless pearls of wisdom:
> 
> ->ATTENTION ALL ENGINEERS AND DRAFTSMEN:
> 
> I'd suggest before you get out into the real world with a female boss that
> you find another word for "draftsMEN".
> > 

In article <5665u7$3pu@Nntp1.mcs.net>, Tommy E.   wrote:
>
>>From: DC, 75277.3335@CompuServe.COM
>
>>>What completes the grounding circuit in an electrical system?
>>Let's say a refrigerator shorts and the current goes to ground (thus
>>protecting anyone touching the refrigerator).
>>The current goes through a wire down to metal pipe down to the earth
>>itself, but how does it come back from the soil in the back or front
>>yard to complete the circuit to the refrigerator in the house?
>>Thanks for help and info.
To clear up a bit of a misnomer, ground has several meanings.  In
general it's used to indicate something that is at zero volts with
respect to a source.  The earth ground is used mainly for protection
from lightening or similarly induced voltages, and is used to ensure
that all wires into a  house are at the same ground voltage with
respect to each other.  This includes phone lines and cable.

>
>The problem, as you might imagine, is when for some reason, say defective
>wiring, you have a high resistance ground connection.   In this case, the
>protective overcurrent device will not trip, leaving the circuit hot and
>the frame of the device at an energized, possibly dangerous potential. 
>If you suspect that you have a high resistance ground, your installation
>should be immediately checked by a qualified electrician.
This is also one of the reasons for ground-fault interrupted circuits.
These can either be at the outlet or an entire circuit, and are
designed to sense when there is a voltage with respect to ground that
may not be high enough to trip a regular breaker.  Anytime a circuit
is to be used in a bathroom, basement, kitchen near a sink, garage
or similar outbuilding, or outdoor circuits, a GFI should be used.
-- 
Anmar Mirza   # Chief of Tranquility  #How many of our  #I'm a cheap
EMT-D         # Base, Lawrence Co.,IN #Bretheren die for#date, but an
N9ISY (tech)  # Somewhere out on the  #every glass of V8#expensive
EOL DoD#1147  # Mirza Ranch.C'mon over#Juice?. TBTW #10 #pet.

Please visit our web site :
BROCHEXPRESS
http://www.brochexpress.com
we are specialized in maintenance of Spindles
our Email 
mailto:brochexpress@meteor.aurecvideo.fr

In article <32864217.3830436@news.nl.cis.philips.com>, 
H.J.M.Laurijsen@nl.cis.philips.com says...
>
>I am searching for a programm for COST ESTIMATING (CAPP) in a
>mechanical workshop (milling, grinding etc.)
>
>Does anyone know such a programm????
>
>
Try Timberline, a demo copy is availabel on the web, use Lycos and
search for Timbeline or estimating.
-- 
M.C. (Mike) Albrecht
koalmnr@sprynet.com
KoalMnr@aol.com
http://www.hooked.net/users/koalmnr
EARTH FIRST!
We will mine the rest of the planets later!

In article , jamcorp@world.std.com says...
>
>
>Hello (good morning?),
>
>        It's 4:00 am and I can't sleep becuase this new injection mold
>we're desiging is driving me nuts.  It's not the mold per se so much as the
>management of the project and a sudden recognition that I keep running into 
>a very similar problem in many different areas of our development effort (on
>automation of LBM manufacturing).  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....
Jon,
I know what you are talking about, except even managers 
can get in on the act.  Just try writing software sometime.
Possible influences at work.
1. Fear of failure.  These guys may have gotten second guessed
and raked over the coals in the past.  "You should have known
this...."  "Why didn't you...."  blah blah.  So everyone gets 
in the habit of playing defense.
2. See a problem - fix a problem.  Engineers have difficulty
letting things go after they recognize a potential fault.
3. The big picture.  Knowledge focussed to a point results
in local decisions that hurt the product as a whole.
In describing 'The Perfect Prince', Machiavelli felt a
leader should carefully collect opinions, then make the 
final decision himself.  An October 16 1996 article in the
WSJ describes the "No" Person, 'A perfectionist motivated
to get every assignment right by avoiding mistakes'.  This
article is titled Hints on Managing Those Nightmare 
Employees.  Again, the article advises using these people
as a resource or an early warning system, but move ahead (and 
accept the risk) on your own.
It's a delicate balance to keep these guys working for you,
coming up with ideas and possible problems, while you
prune these ideas in public view.  I wasn't very good at it
myself and was an asshole more than once.  But I learned 
the hard way that the bleeding wouldn't stop unless I made 
it stop.
If getting a consensus is important, then consider a formal 
decision process where you can numerically state the importance 
of a low cost solution.
If you are lower down on the totem pole, then heaven help you.
Regards,
Pete Hughes 

:Electrons like water current must have some pressure difference between
:their present location and where they are going in order to make them
:flow.  This electrical pressure is measured in volts.
geez. simple question why all the complicated answers?
Obviously the key is insulated from the hot part of
the electical circuit in the switch.
-- 
george 	
george@mech.seas.upenn.edu

I cannot imagine not doing this myself. 
Why would anyone ask for ideas???
Such projects are, after all, what engineering is all about.
But, here is a clue that is always a good idea in engineering:
	"Where ever possible.....model nature!"	  
			     (I'm not sure of quote source)
Any other good clues like this, are welcome?

In <566b9u$qjs@milo.mcs.anl.gov>, curtis@anl.gov (Jeffrey S. Curtis) writes:
>DC <75277.3335@CompuServe.COM> writes:
>}Why doesn't a person electrocute himself when he turns on the 
>}ignition in a car, since he is holding a metal key contacting metal 
>}leads (to the battery) in the steering column, and moreover his body
>}is touching the car's ground (its frame)?
>
>Because your assertion is false
Yep. The ignition key is a switch -- and like a light switch, the contacts are
insulated. (Exception would be VATS keys, where the system passes a current
thru the key's ID pellet to validate it.)
Yep again: Usually the driver's body is in contact with the seat, steering wheel,
and other insulated surfaces, so even if the lock was live there's be no current.
And yep again, 12V is harmless. Put one hand on each terminal of your car
battery sometime; you won't even notice it. Most of us who work on our own
cars have done this, or the equivalent, more times than we can count. The
spark plug voltage might do a bit of damage, though.
My grandfather was a practical electrician for many years, and did a fair amount
of work on early elevators. He reports that a friend of his had a patented technique
for determining the voltage across a pair of wires: Being careful that no other part
of his body was grounded, he'd brush two fingers of the same hand quickly across
the bare wires. If it tingled, it was 110. If it startled him, it was 220. If it _hurt_, 
it was 440. There's a word for this technique: "Stupid". But it points out that 
current across one hand isn't likely to kill you; the real danger is a hand-to-hand
or hand-to-foot current which could pass thru the heart and stop it.
There are other factors as well. Certain currents and frequencies will cause
muscles to lock up, with the result that if you grab the wire you may not be
able to let go of it again. Some waveforms are more likely to stop the heart
than others. VERY high voltages and frequencies tend to flow along the 
surfaces of objects rather than thru them, which is why people have 
survived being struck by lightning. (Ask the rangers at Rocky Mountain for
their stories about how many times they've been hit!) And so on.
Key point: If it's low voltage, it may cause a fire if there's enough current
behind it but it won't shock you. If it's higher voltage, keep yer mitts off it
unless you know what you're doing.
 ----------------------------------------------------------------------- 
Joseph J. Kesselman             http://pages.prodigy.com/keshlam/
"This note is a production of Novalabs Consulting, which is solely       
responsible for its content. Opinions not necessarily those of IBM."

Gary,
Thanks, for pointing that out. Out of the three of us working on this
survey one of them is female. She is actually the one whom came up with
the start of the survey. I questioned her about the wording and she said
it didn't matter. I for one am open to both male and female co-workers.
I  am not sexists at all.
Gary Lynn Kerr wrote:
> 
> To whom ever wrote that the term draftsMEN was not correct.  GET A LIFE!
> When the word men/man is used in a word it is generic and means mankind.
> And a female boss has a problem with it she has too much time on her
> hands.  Also that same feMALE boss probably would not liked being
> referred to as feMALE/woMEN.  As I said before GET A LIFE!
> 
> On Sat, 9 Nov
> 1996, Jim Weir wrote:
> 
> > Peter  shared these priceless pearls of wisdom:
> >
> > ->ATTENTION ALL ENGINEERS AND DRAFTSMEN:
> >
> > I'd suggest before you get out into the real world with a female boss that
> > you find another word for "draftsMEN".
> > >

T Lipton  wrote in article
<01bbcfee$47822c20$26f71fcc@brianh>...
> 
> 
>    Can anybody give me a quick explanation on how Coriolis effect
> mass flow sensors operate? 
> 
>   Thanks in advance  TML
> 
Here is an explanation.  Check out the E+H web page for additional
information.  The web site is located at URL http://www.endress.com.
Coriolis Mass Flow Measurement
The measuring principle is based on the controlled generation of Coriolis
forces.  These forces are always present when both translational (straight
line) and rotational (revolving) movement occur simultaneously.
Fc = 2 · Dm (w x v)
Where:
Fc = Coriolis force
Dm = mass of moving body
w = angular velocity
v = radial velocity in a rotating or oscillating system
The amplitude of the Coriolis force depends on the moving mass Dm, its
velocity v in the system and therefore its mass flow rate.
The Endress+Hauser Promass uses an oscillation instead of a constant
angular velocity and two parallel measuring tubes with fluid flowing
through both tubes.  These parallel tubes oscillate at a resonant frequency
(approx. 1000 hz) much like a tuning fork.
The Coriolis forces produce a phase shift in the oscillating tubes.  When
there is zero flow, both phases are equal.  When there is mass flow, the
tube oscillation is decelerated at the inlet and accelerated on the outlet.
 As the mass flow rate increases, the phase differences also increases. 
The measurement principle applies independent of changes in temperature,
pressure, viscosity, conductivity, or flow profile.
Density Measurement
The measuring tubes are continuously excited at their resonant frequency. 
As the mass and therefore the density of the oscillating system changes
(measuring tubes and fluid), the vibrating frequency changes.  The resonant
frequency is thus a function of the density of the fluid.  The density
measurement is output from the Endress+Hauser Promass 63 mass flow meter.

DC wrote:
> 
> Why doesn't a person electrocute himself when he turns on the
> ignition in a car, since he is holding a metal key contacting metal
> leads (to the battery) in the steering column, and moreover his body
> is touching the car's ground (its frame)?
> Thanks for clarifying this.
> 
> --
> From 75277.3335 at CompuServe
Are you kidding w/ this question.  Why don't you blow yourself up when
you blowdry your hair while standing on a wet floor in the bathroom??? 
SAME CONCEPT!!!

> In article 
>            jamcorp@world.std.com "Jonathan Priluck" writes:
> 
> >
> > Hello (good morning?),
> >
> >         It's 4:00 am and I can't sleep becuase this new injection mold
> > we're desiging is driving me nuts.  It's not the mold per se so much as the
> > management of the project and a sudden recognition that I keep running into
> > a very similar problem in many different areas of our development effort (on
> > automation of LBM manufacturing).  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.
> 
> [%X]
> 
> > ......................... 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?
You know, this is funny, because I am attempting to start a competition
here at Carleton University in which competitors (engineering students)
are required to perform relatively simple tasks, like getting a ping
pong ball out of a cylinder, using only the tools provided (duct tape,
tubing, etc.).  There are some extremely simple solutions that most
students would overlook, and that's the point of the competition.  It is
my experience as a student and as a teaching assistant that students
believe all problems are difficult.  Professors never ask questions with
simple common sense answers (in the students view).  The reason for
this, of course, is to challenge the students, weed out the bad ones,
and reward the good ones for finding the solution.  But something is
missed.  On the job, the best engineer is the one who can come up with
the simplest, cheapest solution.  In school, the best engineer is the
one who can solve the most difficult problem.  I'm hoping this
competition will make some things click in the students mind.  I
definitely agree that this is a problem, even at the academic level.
--
    ("`-''-/").___..--''"`-._         
     `6_ 6  )   `-.  (     ).`-.__.`)  Chad English
     (_Y_.)'  ._   )  `._ `. ``-..-'  cenglish@mae.carleton.ca
   _..`--'_..-_/  /--'_.' ,'       http://www.mae.carleton.ca/~cenglish
  (il).-''  (li).'  ((!.-'

mchalefla@worldnet.att.net wrote:
> 
> 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
> 
> 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?
punk?  moi?  and who are you, that you are above criticism?  could you
show me your current  "shit doesn't stink" card, please?
> 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.
yes, you do take yourself quite seriously.  perhaps a bitt too
seriously, I might add.  It makes you look rather, um, insecure.  I
wasn't questioning you intelligence, actually, I was questioning your
laziness, or rather it's opposite.
  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.
that, and a solution to your problem. Additionally, the less time and
effort on your part, the better.
> 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.
sorry.  Just trying to help.
Sorry to everyone else for beating on this rather large, obvious dead
horse.
.

>
>What completes the grounding circuit in an electrical system?
>Let's say a refrigerator shorts and the current goes to ground (thus
>protecting anyone touching the refrigerator).
>The current goes through a wire down to metal pipe down to the earth
>itself, but how does it come back from the soil in the back or front
>yard to complete the circuit to the refrigerator in the house?
>Thanks for help and info.
>
Simplistically, think of the power coming down the "hot" wire from the 
power transformer and normally returning to the transformer down the 
"neutral" wire.  When you have a fault in your appliance, the current 
returns to the transformer via the ground wire (and the earth itself)
which is connected to the neutral at the transformer, so the circuit 
is completed. It doesn't need to get back to the refrigerator to complete
the circuit. It has already been there - done that - bought the T-shirt.