Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: Wood Grading Stamp

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Scott,

Thank you for the enlightenment.

" An example is that one difference between grades like No2 and Select
Struct is the number and size of "permitted" knots in the middle 1/3 of the
span (i.e. where the bending stresses would be greatest for flexural
members).  Thus, if you bought a 20 ft 2x6 with a stamp for stay Select
Struct and then cut it into 2 10ft beams, then the grade stamp that you have
is potentially no longer valid (it might still be valid if the size and
number of knots along the whole length meet the requirements for the middle
1/3 of the span for Select Struct)."

This is why I always spec out #2 or better, and I try and utilize readily
available wood species.

"Another reason is that timber is generally not grade stamped is that is is
generally left exposed for aesethic (as in the "rustic" look that was
mentioned) and architectural reasons.  Now if you just paid a bunch of money
to have a timber framed home with a lot of exposed timbers for aesethic
reasons (i.e. want that "rustic" look), would you want a wonder, black ink
grade stamp staring back at you while sitting in your "rustic"
home in front of the fire?  Don't think so."

This makes tons of sense, however, I was unsure as to how this type of
material would show up on site and if a contractor would actually use
"Visually Graded Lumber" as opposed to "Machine Graded Lumber" for this type
of practice.  Again, I don't mean to sound combative (which the written text
often times can come across), but rather, I am looking for more information
on the subject as well as a little bit of enlightenment.  Also, would you
care to explain the process of "Machine Graded Lumber"?

"An example is that one difference between grades like No2 and Select Struct
is the number and size of "permitted" knots in the middle 1/3 of the span
(i.e. where the bending stresses would be greatest for flexural members).
Thus, if you bought a 20 ft 2x6 with a stamp for stay Select Struct and then
cut it into 2 10ft beams, then the grade stamp that you have is potentially
no longer valid (it might still be valid if the size and number of knots
along the whole length meet the requirements for the middle 1/3 of the span
for Select Struct)."

And this is why I hand pick all of my lumber at the yard, looking for both
splits, checks, knots, twists, bowing, and any other "yuckys" I find
undesirable.  But that's how I was taught, thus, how I roll.

Again, thanks for the enlightenment, and I appreciate your, both, candid and
intellegent responses to these issues.  It's nice to have a "professional
perception" on issues like this.  Obviously, this is not my forte.  Of the 8
years I've been doing this, I can count on one hand how many projects I have
used wood on and still have fingers left over.

Sincerely,
David Maynard, PE
Gillette, Wyoming
--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.344 / Virus Database: 267.10.19/92 - Release Date: 9/7/2005


******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ********