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.A razor sharp blade thenvertically slices the log into veneer.(2) Drying.Veneer is fed into large dryer ovens designed to reduce the moisture content of eachpiece to facilitate a strong, permanent adhesive bond.(3) Lay-up and Gluing.When the veneers have been dried to their specified moisture content, theyare conveyed to a lay-up operation, where a urea-formaldehyde adhesive is applied.The pieces arethen glued to a plywood core.(4) Pressing.The laid-up assembly of veneers is then sent to a press designed to press the glue intoa thin layer.After being unloaded from the press and after cooling, panels are trimmed to precisesizes.(5) Sanding.To smooth raised grains and/or remove glue from the surface, the panel product isoften sanded using manual or automated sanders.(6) Grading.After sanding, the plywood is graded and prepared for storage or shipping." A conventional veneer manufacturing process typically relies on large pieces of equipment (e.g., hotwater soaking tanks, veneer slicers, drying ovens) that typically cost several million dollars.Forexample, conventional wood dryers typically cost $1.5 million for a 20 foot by 100 foot oven thatblows 180 degree forced air on the wood. Lean Manufacturing and the Environment October 2003 | Page 55" The primary environmental impacts from conventional veneer manufacturing include air emissions,energy use, and run-off.The primary source of air emissions are organic compounds from the dryingprocess.The type and quantity of emissions depends on the wood species and type of dryer, but aretypically ducted through separate stacks (for heating zones and cooling sections).Hot pressingoperations also release some volatile organic compounds (VOCs), but these emissions typicallyremain uncontrolled.Particulate emissions (PM) typically result from log debarking, cutting andsanding, and drying and pressing.Organic compound emissions (formaldehyde and other hazardousair pollutants) can also result from gluing and hot pressing.Sawdust and other small wood particlesare generated by cutting and sanding operations, which are typically controlled and collected to useas fuel.Wood storage piles can also be a source of PM and VOC emissions.Uncontrolled runoffcan also result from large inventory piles, because unused logs need to be sprayed with water toprevent cracking." Another environmental dimension of cherry veneer manufacturing is the deteriorating supply ofblack cherry trees in Pennsylvania.Although the Allegheny Plateau contains some of the highestquality black cherry trees in the world (particularly well suited for high quality veneer), their supplyis limited.In part, this is because conventional veneer manufacturing practices require high quality,defect-free logs that can produce 12-foot veneer slices.This length requirement, in turn, frequentlyrequires companies to harvest large diameter mature black cherry trees." Veneer products can provide environmental benefits by significantly reducing the consumption ofslow growing, high quality hardwoods.With veneer which is typically 1/42 thick, one hardwoodtree can cover approximately 20 times as much furniture when compared with using solidhardwoods.Often, veneer is laminated onto cores of particle board or mdf which often contain acombination of wood waste products and chipped up low grade logs.Putting lower cost fastergrowing species in the core of a veneer-covered furniture component is good for the forest.Applying Lean Principles to Veneer Manufacturing" Apollo Hardwood's founders see an opportunity to significantly reduce the amount and cost ofcapital required for veneer manufacturing.This opportunity stems from lean principles thatemphasize making capital investments only where necessary and when necessary, allowing for thehighest possible return-on-investment.This strategy is particularly relevant to start-up companies,where one of the quickest routes to profitability is minimizing capital costs while producing a qualityproduct.Conventional manufacturing wisdom might lead a company to buy larger equipment, sothat the plant can accommodate production increases.Lean thinking, however, suggests that thecompany may be better served by investing in capital needed for current production, and addingadditional capital incrementally to meet growth needs.This lean strategy relies heavily on theavailability of right-sized (and sometimes mobile) equipment that can be easily replicated (andimproved) at significantly lower cost when compared with large, conventional equipment (e.g., monuments )." Conventional debarking, cutting, slicing and drying equipment have many attributes of monuments,and these processes were targeted by Apollo Hardwoods.The goal was to find a less capitalintensive process for slicing and drying veneer that would also address other business needs suchas product quality, flow time, and cost.Since such a process and associated equipment were notavailable, Apollo Hardwoods sought to develop them in-house using the lean method typicallyreferred to as 3P (pre-production planning).The 3P method was initially developed as part of the Lean Manufacturing and the Environment October 2003 | Page 56Toyota Production System, and it focuses on optimization and waste elimination at the productand/or process design stage." Apollo Hardwoods recruited a team to assist in a series of 3P events to design a lean veneer slicingand drying process and associated equipment.Team members were carefully selected to ensure thatthe team did not have too much familiarity with conventional veneer manufacturing methods, whichcould limit creativity during the 3P events.Success parameters were set for the 3P events thatarticulated the desired takt time (i.e., the rate at which product must be turned out to satisfy marketdemand) and a dollar limit for building the process equipment
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