NBE Scanner / Optimizers
Carriage Description
www.millsmart.com/carriage.html - 503.625.4101-
Updated 20-Dec-05
Robert Cecil was
convinced that the world needed both front and back scanning on Headrig
Carriages. His experience with
other vendor’s systems convinced him that there was just too much guessing and
not enough data. When Robert
started working with NBE in 2000 he tried to convince me (Rod Nelson). Well, I am the person that forecast the
demise of Carriage systems back in 1992, so he did not have much luck. But Robert was determined, so when
JoeScan started making scan heads and they were proving to be extremely
reliable, Robert went ahead with his plan. In 2003, he installed the first front and back scanner with scan
heads riding on the carriage. He
has done 4 more since then and has 2 scheduled for the first quarter of
2006.
OK, Robert was
right and I was wrong. So, why do
carriages still exist and why is front and back scanning important.
Carriages
Why do carriages
exist? Well no other primary
breakdown machine can handle a wide range of diameters, lengths and log shapes,
and produce products for any downstream machine center. It is the best machine for pulling high
grade boards of the sides of logs.
Carriages may not be the fastest but they are the most flexible.
Front and Back
Scanning
Why do you need
front and back scanning?
Historically,
headrig scanners would only scan the front side of the log and attempt a minimum
opening face. This would guarantee
a usable first board, reveal the grade to the operator and preserve the most
wood to be used on the backside. We
like to call it the Dark Side, since it does not get scanned, and too little is
know about it. On smaller logs or
logs with no potential for grade improvement, this scanning method pushes all
excess to the back, thus guaranteeing that wood is wasted on the backside.
The
concept of minimum opening face needs to be forgotten. When NBE did their early cant
optimizer, we spent a lot of time convincing people that sometimes a 6” or 8”
opening face is the best decision.
But we needed to scan both side of the cant to be able to make the best
decision. No one tries to sell a
cant scanner that only scans one side.
Why would anyone want a log scanner that only scans one side?
Also
over the years I have come to realize that most optimization code has been
written to overcome insufficient data or bad data, or insufficient computer
horsepower. These early optimizers
required extensive setup tables with diameter, length, taper and sweep rules
that would direct the optimizer to make a reasonable decision in spite of the deficiencies.
With
surround scan, you have the necessary data and today’s computers are fast. So you can define your lumber products
the same way as you would on a trimmer or edger and let the optimizer do the
rest.
To Be Continued