Virginia Tech Researchers Urge Single Grading Method for Cants
Cant Grading : Researchers at Virginia Tech recommend the establishment of a single or minimum grading method to differentiate quality of pallet cants..
By Staff Writer
Date Posted: 4/1/1999
The pallet industrys top researcher and three colleagues have recommended the establishment of a single or minimum grading method to differentiate quality of pallet cants.
The proposal was outlined by Dr. Marshall ("Mark") White, director of the pallet and container laboratory at Virginia Tech, at the recent annual meeting of the National Wooden Pallet and Container Association in La Jolla, Calif.
Mark made a presentation on research into pallet cant grading conducted by him and three Virginia Tech colleagues and said the proposal would be submitted to the NWPCAs standards committee for consideration. A single, minimum hardwood cant grade could substantially increase profits of pallet manufacturers by weeding out cants of poor quality that cost them money, he suggested.
However, Mark conceded the idea likely would be given a cool reception by the hardwood lumber industry. If the NWPCA decided to pursue the initiative, the route would be to ask the National Hardwood Lumber Association to endorse the proposal and include a minimum grade for pallet cants in the associations grading book. "Thats going to be a really hard sell," he admitted.
"Its going to be a hard sell to the lumber industry, I know that....But we have to start sometime and some where. And I think we have some data to begin to push the agenda a little bit."
The other Virginia Tech researchers who participated in the study were Hal. L. Mitchell, Philip Araman and Cynthia West. They conducted yield studies at 28 pallet mills in the Eastern U.S., sampling more than 47,000 board feet of hardwood cants. Bundles of cants were randomly selected and graded No. 1, 2, or 3 according to a proposed grading scheme. Cants were graded No. 1 for 0-15% unsound wood, No. 2 for 15-30%, and No. 3 for over 30% unsound defects. The pallet mills sawed the cants into parts using a wide range of sawing systems, both gang circular saws and thin kerf band saws. The study relating cant quality to pallet part yield was the first of its type, according to Mark.
Although the study was based on three proposed pallet cant grades, the findings led the researchers to recommend the establishment of only a single, minimum grade. "The beauty of this study is, we think three grades are dumb," Mark told a gathering at the NWPCA meeting. "This study shows that...in the world of grading cants, one minimum grade makes a lot of sense."
The cost of raw material is more than the price of cants, Mark noted. The cost of raw material includes the cost to the pallet manufacturer to saw the cants into pallet parts and also is impacted by the yield of parts. A grading system could help pallet manufacturers more accurately determine raw material cost and help sawmills determine cant value.
Mark noted that pallet manufacturers in the Western U.S. already are familiar with and used to dealing in graded softwood lumber. Utility and economy grades are the grades of choice on the West Coast. "The point Im trying to make is that we dont have a corresponding standard grade in the East for hardwood," he said.
Under the three proposed grades, the study showed that pallet part yield was 83% from No. 1, 77% from No. 2, and 47% for No. 3. Nearly 90% of the cants sampled were graded No. 1 or No. 2. "And by the way, youre making money on these," Mark said. By contrast, pallet mills that saw poor quality cants are losing a "tremendous amount of money," he said.
Average losses from defects were 2% for the No. 1, 8% for No. 2, and 39% for No. 3. Cant quality significantly affects cost, said Mark. "If youre paying the same price for those cants, theres a huge difference in cost to you for those cants."
"What it tends to shows us, that if its in any way practical to grade cants using one minimum grade, it looks like that separation between proposed 2 and 3...is about right," said Mark. "We feel that probably because there was very little difference between 1s and 2s in our study, because theres a huge difference in 2 and 3...a first definition for the minium quality of a hardwood cant in our market today should be based on a 70% minimum yield, or thereabouts...Or a 30% unsound."
"Clearly," he added, "the study shows that when we exceed this 30% level, were losing money on those cants."
A minimum grading system would provide several benefits to the market place, according to Mark. It would help stabilize cant and pallet lumber costs; when a minimum quality is defined and pallet manufacturers begin buying to that standard, a higher level of price stabilization would result, he said. A grade also would provide the basis for a more realistic pricing scheme, and sawmills would divert additional material for pallet cants and less to alternative markets. Lastly, a grading methodology would improve communication between buyers and sellers.
A sawmills cost should not necessarily increase by sorting pallets to a minimum grade, Mark said. "Were only talking about one grade, a pallet cant grade. Were telling them to separate the low quality, but in the end theyre still going to have to stack only for 4-by-6 pallet cants." The only exception would be an additional "pull" from the green chain for a short, he acknowledged. (Instead of chipping poor quality cants, Mark suggested that sawmills should cut them back to a short and sell them as a short to the flooring market or pallet market.)
"Lets develop a minimum grade. Lets try to get those out of the system. Adjust the pricing for the cant so its a win-win," Mark said.
The study determined that average kerf loss with band saws was about 6%, and for circular gang saws, about 13% for a difference of 7%. "Emphasis on kerf, I think, is worth-while," Mark told the audience.
When cutting multiple-length pallet parts from cants, yield tended to be slightly higher about 2% than cutting the same-length parts out of cants, the research showed. "When you had an order where you had to cut all one size, you were throwing away yield," Mark said. "That was it."
The study also looked at a simple grading technique that is used in many pallet mills. The simple grading method is based on counting the bad ends. The researchers did the same thing. "Theres no relationship between the part yield and bad ends," Mark concluded. "Couldnt find any relationship."
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