Fw: about the SNAME Thread

Bolgerites,

I have been boating a lot (Apalachicola Festival, Cedar Key Small Boat
Meet), so didn't realize the SNAME/WB thread lived on here. I'm pasting in
a couple of posts I made to the "boatdesign" list, from the viewpoint of a
"recovering Registered Professional Engineer". if you have seen them,
forgive me. BTW, "harbinger" is Tom Lathrop, whose 24-foot lightweight
powerboat appeared in two Boatbuilder articles (design, construction) - a
very elegant design that, say, Dave Gerr, NA would envy...

Don Hodges
www.ECoastLife.com
Your Emerald Coast Cyber-Vacation
Small-Boat Building, Fishing, Cruising

----- Original Message -----
From: Don and Dianne <don_dihodges@...>
To: <boatdesign@yahoogroups.com>
Sent: Friday, May 04, 2001 8:14 AM
Subject: Re: [boatdesign] Digest Number 652


> My experience is similar to "harbinger" (didn't see a sig on that post).
> Georgia Tech '61, more grad studies in '65, then went to Delta Air Lines
as
> an engineer on engines and airplanes. My recall is that NO corporate
> product requires a PE, the manufacturer undertakes all responsibility for
> design. In fact, engineers for users (say retrofitting a truck to
increase
> towing capability) are required to obtain mfr's consent for product
changes
> unless the product is fully re-engineered and documented, when a PE may be
> useful as a credential.
>
> I got over into airport development and equipping, which brought me in
> contact with a lot of PE's doing the airfield and building designs, where
> the credential was helpful to me, rather than just getting into an
> "engineering contest" when we differed. I took the Engineer-In-Training
and
> the PE exam in Mechanical Engineering "back-to-back" at age 40-something,
18
> years after my last college math course. I can't recommend that approach
to
> anyone, but it's a testimonial to the "Atlanta Trade School" that I passed
> both.
>
> The PE is best applied to public works and construction, where the product
> is a "one-off" with public safety issues and a largely uncontrolled work
> force of contractors who must "assemble" the design from drawings after
> getting the work by proving how many corners they can cut (low bidder). A
> product like a boat is more like a manufactured article (most are), and
the
> manufacturer is responsible. If I design a boat as an employee or
> contractor for a manufacturer, he is responsible if it folds up like a
cheap
> umbrella, although I may get fired or discredited. A design for amateur
> construction is a very narrow niche where the "buyer beware" is operative
(I
> bought Tennessee plans from Bolger, but when push came to shove, I
thought
> it a bit light for what I had in mind, and I think PB would agree). A
ship
> is more like construction, a "one-off" usually with public safety
concerns.
>
> My bottom line, as a retired, "recovering Professional Engineer": leave
> this little niche of opportunity "un-institutionalized", let NA's get
> licensed if they feel a need to (like I did), but don't force it by law.
> Ever hear of a guy named Burt Rutan? Probably the most brilliant airplane
> designer living today, and no credentials that I know of - except stunning
> singularities in design, proven by performance records and continuing BIG
> support from suits who would probably not even want him at their home for
> dinner...
>
> End of MY rant - everybody join us at Cedar Key tomorrow, it's always
great!
> (I'm still working on the Apalachicola Festival pix, been too busy in an
> "engineering Contest" with our local big, arrogant consultant (shot
through
> with PE's) who wants to move our capable little airport to the woods in a
> real estate gamble, but I digress...
>
> Don Hodges
> www.ECoastLife.com
> Your Emerald Coast Cyber-Vacation
> Small-Boat Building, Fishing, Cruising
> Updated Opinion on Local Issues

Reply to Roger Coy: (who thinks PE licensing should be "more involved")

Go take the EIT and PE exams back-to-back until you pass both, then tell us
how much more involved you would like to be (I'll let you pick your field of
specialty, mine was Mechanical Engineering...)

Incidentally, you won't have any better judgement about safety factors, etc.
after you pass than you did before. Most materials are pretty well
documented now, so unless you are doing research (not many PE's there), it
is sort of a cookbook discipline for most practicioners.

Most of our boat designers got to where they are by "iterative design" (try
it, if it works, change it a little and see if that works), which is much
more practical than just opening a book on "curved plate structures" and
"wire-stayed columns" and inventing a boat. (Such a boat would probably
float 50% below its proper lines and capsize due to excessive weight aloft,
until the designer got some iterative data to adjust the scantlings.) It is
also why most bridges and hospitals, etc. are far heavier and
materials-intensive than they need be...

OTOH, my boats tend to have a weak spot somewhere because I was optimistic
about scantlings. On the "Emerald Coaster" it is the struts which hold up
the sunroof - so, my next iteration will be aluminum tubing instead of PVC
pipe and closet poles... it's the lurching crew that maxes the stress, not
just holding up a 6x6 arched ply panel.

Don Hodges
www.ECoastLife.com
Your Emerald Coast Cyber-Vacation
Small-Boat Building, Fishing, Cruising
Updated Opinion on Local Issues