Familiar Territory
Ledwidge Lumber relies on a pair of Hew Saw lines to recover quality studs from its private log supply – An older MSA races through the smallest of small logs, while a brand new R200 Plus makes the most of larger logs.
By: Scott Jamieson
Go with what you know. That may well describe recent upgrades at Ledwidge Lumber of Enfield, NS. The family-owned stud mill replaced its ageing twin-saw line with a new optimized Hew Saw R200 Plus small-log line, joining an existing Hew Saw line that has been running for a decade, and making the family-run mill an all Hew Saw affair.
Not that mill management is blind to other technology. You’d be hard pressed to attend a major sawmill show or conference without running into someone from Ledwidge. There, you’d typically find president and general manager Doug Ledwidge or sawmill manager Richard Cox poking into the latest machinery or discussing their challenges and upcoming needs. Still, unless a change is essential, going with what you know is not bad advice.
“We were familiar with Hew Saw, and have had good success with the approach,” explains Doug. “Still, this new line was new technology for us, and for Hew Saw. It was the first R200 Plus in North America, and the first Plus coupled to the double rotor log positioner. It was also the first one that Prologic had done the optimization and controls on, and it was more complex machinery then we had been used to. A lot has changed since we got that first Hew Saw.”
Small & smaller
Indeed much has changed since the Ledwidges installed their first Hew Saw small log line in 1997 in a move to gain more buying flexibility in the region’s almost 100% private log market. In 1996, the mill sawed 31 million bdft/yr, a record year at the time. In 2005 Ledwidge cut over 70 million bdft, despite market challenges and having started up its brand new line in January of that year. While the original Hew Saw sports the supplier’s classic banana-style infeed, the R200 Plus boasts a fully optimized infeed with log rotator and positioner, an addition Ledwidge expects to improve recovery from its larger, more valuable logs.
In the upgraded mill, incoming 8-ft logs are set on an infeed deck by Prentice ATL 425 or brand new Fuchs 460MH loaders. The mill currently relies on two older double ring debarkers run by a single operator. Handling the mix of fir (30%) and spruce, they currently top out at 285 ft/min or a maximum of 25 logs per minute each, making debarking a target for future upgrades.
“It’s a bottleneck for us with the new line, and we’re looking at options to speed it up,” Doug explains. “The key is doing so without damaging our fir component or affecting chip quality in the process.”
After each debarker are Prologic log sorters, which use a shadow scan and two laser line scanners to sort the logs by solution. The original Hew Saw R200 MSA handles the smallest logs now, with four sort bins feeding four ribbon-fed patterns – a single 2x3; a 2x3 and 1x3; two 2x3s;and two 2x4s.
“The new Hew Saw is positioned so that we can run as a single-line mill if need be,” says Doug, “but that’s not our intention. We process a lot of very small logs, so we like to have the old line dedicated to those. Larger logs, or those that the sorter decides would be better off going to the newer line because of defects like excessive sweep or double crook are sent there.”
This original line now races through these smaller logs at a pace of 33 or 34 a minute, fed from each bin by Linden step feeders. Doug notes that the older style banana infeed has issues with double crook or infrequently misses the horns up goal, but adds that it still puts out some respectable recovery numbers given the log supply.
“There’s some trim back to 7-ft, which hurts us, but we work on that, and we see room for even higher production yet from that old line. It’s still a main producer.”
The “large-log” line enjoys the relatively leisurely pace of 20 or more logs per minute. With just two sort bins ahead of the R200 Plus, the line is fed in scan-n-set mode and processes logs with larger patterns or that can benefit most from the more sophisticated log positioner. The infeed has full-profile scanning driving an optimized log rotation system, all controlled by Quebec-based Prologic. The log turner is a dual rotor design, with the first turner doing all the rotation up to 89 degrees, and any rotation over that being split 50/50 between both rotors. The Ledwidge crew had spent a lot of time investigating various log turning and positioning options, and had healthy skepticism regarding accuracy in real world conditions. In the end, Doug says, the Hew Saw positioner has done what the suppliers said it would. It has passed what the mill felt is the industry norm of +/- 15-degree accuracy, and is now performing much better than that. Still, Doug was not surprised that it took all parties some effort to get there.
“We have some pretty rough logs from time to time, with big knots and flared butts, and that’s what the line has to handle, without slowing down – we’re not about to kick out a lot of logs that we’ve paid for because they’re a little on the ugly side, although that would make things easier. Hew Saw and Prologic worked very well with us – they are great guys to work with – and in the end they did a fantastic job. They adjusted the pressures and beefed up the traction on the rollers, and now it’s where we want it.”
Accelerating
With accuracy under control, the next quest is speed. The line started up at 600 fpm, but with some initial trouble was dialed back to 500, and then brought back to 550 where it runs on the smaller logs today. The log gap was about 13 feet when CWP was on site, but Doug says they have plans to drop it to 12.
“That’s doable, and I know we can speed it up too, but right now with the limitations at debarking, there’s no point.”
Both large-log bins use Comact wave feeders, and since the optional gap control system is not yet installed, the mill has another avenue to pick up production down the road.
After rotation, logs go through the Hew Saw’s four-sided chipping canter, and then on to a doublecluster saw section.
“We went with the two different clusters so that if one gets dull or isn’t working well, we just push a button, wait a second, and then continue running with the other cluster.”
The new Hew Saw includes edging tools, so that all lumber passes from both lines right to the green chain, with little edging required.
Thinking, not spending
On the green chain, Ledwidge has two graders marking fir and rot trim backs, which in addition to super wet fir sorted out by a downstream CRIQ/Gemofor weigh scale, will be kiln dried in separate charges.
“We also find the appearance grade products dry a little differently, so we sort them out in the sawmill. It means a little more rough inventory, but it allows us to optimize our kilns, and has helped keep our sorts down in the planer. We don’t have a sorter in the planer mill, so our goal is to have one prime sort that goes right to the stacker, with the rest going to two or three guys stacking the odd piece. It has helped keep the planer mill simple, and investments under control.”
The green end is completed by a PLC lug loader, Lucidyne grade mark reader, Autolog trimmer optimizer (recently upgraded to higher resolution scan heads), Carbotech fence, multi-saw trimmer, 63-bin sorter and stacker-sticker placer. The latter is the main bottleneck in the mill back end now, and Doug says they are investigating options to speed it up.
The mill has also recently updated its drying operation to keep pace. To its two Wellons dual air pass track kilns it has added a Coe package kiln bought in a bankruptcy sale. It, along with a refurbished Wellons/FEI 250-hp, low-pressure steam boiler was commissioned earlier this year by inhouse kiln controller Mark McGrath.
“We will dedicate the package kiln to fir,” Doug explains, “and with the associated 70 to 75 hour schedule, will not be penalized as much by the slower loading and unloading times. The boiler will allow us to run the new kiln as well as heat the sawmill.”
With the investment, Ledwidge’s annual drying capacity climbs from a borderline 65 million bdft to over 85 million bdft, allowing for future growth.
In 2005, the mill produced 70.4 million bdft, an increase of almost five million bdft over 2004 despite the start up, “and we intend to ramp production up further still,” Doug says. The mill ran double shifts for 10 months during 2005, running singles the rest of the time to adjust log supply and inventories. Early in 2006 the mill was on single shift, but jumped to doubles in March.
As the new line ramped up, the mill continued to run the old twinsaw line to make sure production was not sacrificed. It then sat idle for months while Doug made sure it was not required. As of press time, the cautious manager felt confident enough to offer the old line up for sale. Ironically, when CWP first visited Ledwidge early in 1995, this twin PHL line was the mill’s newest high producer.
As for the staff, however, obsolescence is never an option. Doug notes that the capable crew has adjusted very well to the new line, and with the increased running hours and production, very little in the way of staff reductions were required.
“There was some hesitation at first, which is natural. This system is a lot more complex then the older line, with over 21 axes of control and movement in a very tight space. Yet as soon as we started training on the new system, everybody really embraced the technology, and the operator on the twin line is now our dayshift operator on the new Hew Saw. Just yesterday we put almost 24,000 logs in a single shift on the two lines. That’s a lot of logs, yes, but we need to do more yet.” In fact, in all the predicted areas, the new sawline project has paid off, Doug concludes.
“It has helped us quite a bit. We’ve seen a 10% mill-wide jump in recovery, an increase in 8-ft lumber production, which is key, and quite an increase in grade value recovery – more appearance, more on spec, more 2 & better – it’s all where you need to be today.”
