File Week

Canadian Forest Industries is highlighting innovations in the filing room, from new processes and techniques to new technologies, during File Week 2018 from April 30 to May 4!

For the second year in a row, our File Week coverage is serving as a hub for saw filers and sawmillers to learn best practices and find the latest information on advancements in saw filing technology.

We’re posting cutting edge content both from our archives as well as brand-new stories and product news from the BC Saw Filers Association convention that took place April 26-28 in Kamloops, B.C.



We are highlighting:

  • stories from the filing room
  • technical articles on saw filing automation
  • equipment spotlights on the latest saw filing gear
  • columns from long-time contributor and filer Trevor Shpeley, head filer Josh Penner, and Modern Engineering’s Udo Jahn
  • strategies for employing the next generation of filers, and more!

Stay tuned to this landing page and our social media (#FileWeek) for the latest stories and videos during File Week 2018!

Facebook: www.facebook.com/CanadianForestIndustries

Twitter: https://twitter.com/CFIMag



June 18, 2014 - If you’re exposed to any media (newspaper, television, online, etc.) you can’t help hearing the prediction that there’ll be a lack of skilled employees in the future. After writing about this issue in the past, I received quite a few emails: many were very positive and others directed me to similar articles on the same subject.

Usually the stories we hear are meant to be dire predictions of our future. Yet when you look around and see a large number of unemployed people, you can’t help but wonder why there’d be a lack of people for future jobs. But what’s key here is the word “skilled.”

One of the articles talked about what the writer refers to as a “skills gap.” There are approximately 1.3 million unemployed Canadians and 200,000 unfilled jobs. This indicates that none of the 1.3 million people are qualified for these jobs. I find this very distressing.

One article went on to say, “business owners often admit that they are in the business of making money, not training workers.” What seems to be addressed as a possible solution is to increase immigration of those who are presently trained and skilled. I, myself, am an immigrant but this solution is over the top. What are we thinking? We are ignoring the real problem, which is the lack of proper training within our own country.

I predict employers will continue looking for their future employees by advertising in the media and online. And I compare this strategy to fishermen fishing in the same spot, which results in terrible fishing because the area becomes overfished: resulting in not enough fish to supply the demand.

The probability of finding a good, skilled employee through the usual methods will be very unlikely. So how are we going to find our future “skilled” employees? Many people want the government to do more. Others don’t even recognize that this will be an issue. It’s interesting to note that everyone seems to find this a complex problem with very few solutions.

I have spent time speaking with my peers about “skilled” labour shortages and we believe the problem has a very easy solution. It’s time for businesses to invest in the younger generation. We need to create paid training positions to train our future employees.

I can already see your eyes rolling. Your first concern is “as soon as I finish training them they will be snapped up by other employers.” This concern quickly puts up a defensive wall, and it is likely the reason we have a lack of skilled labour in the first place. The problem is that we look at this as a one-time occurrence instead of an ongoing commitment as part of business.

Employees are, in fact, loyal to the people who train them. This is not to say that if you train them they’ll be there for their entire life, but if you’re constantly training new people then you’ll create a stable workforce.

Your next concern, “but this training is going to cost a fortune.” Instead of looking at this as a cost, employers need to look at training as an investment in capital (just as you invest capital in equipment, you need capital investment in your people). This outlay should be part of your budget each year, and I predict that if you don’t start setting aside dollars for this investment in human capital, you’ll be left behind when it comes to a skilled workforce in the future.

Some people ask about why the government is not leading this. I believe that the government is investing in trades education and now it’s up to employers like us to do our part. Education gives you knowledge, but not the hands-on experience that only industry can provide.

Long-term planning requires businesses to invest in employee training, so they have the ability to meet job demands of the future. If businesses invested more in training, Canada would not have a skills shortage and unemployment rates would be lower.

Sounds like a simple plan, doesn’t it? Well, I think Ronald Reagan said it best, “They say the world has become too complex for simple answers. They are wrong.”


Udo Jahn is the General Manager of Modern Engineering located in Delta, B.C. The company is best known for taking the most complex precision machining problems, and delivering machined parts that are both exact and on-time. Find out more about Modern Engineering by visiting their website at www.moderneng.com.
April 18, 2016 - Gap control is the one of the most critical items to control in a sawmill. It determines how accurate your cuts are, and the quality of your lumber. Having gap control means maintaining that perfect 0.0015” gap between the saw blade and the babbitt pad of the sawguide. I have always looked at sawguide accuracy as one of the top five ways of maintaining a perfect gap.


Too tight of a gap and the sawguide begins to act as a disc brake, which causes your saws to heat up quickly. Having heat buildup means there’s a high probability that your saw blade will lose tension and fold over. If the gap is larger than the ideal amount, you will get a lot of within board deviation (saw wandering) while the saw is cutting, which will result in poor quality lumber.

I thought I had written about almost all the causes that affect the gap size between saw blade and sawguide until recently, when I ran into someone who reminded me of yet another cause, which brings me to this blog today.

“What about the tolerance of the saw plate?” this person said to me. I was silent for a good 15 seconds, with a confused look on my face the whole time. “What about it?” I replied. “It can vary too,” he replied. This caused me to stop and think, because I had never taken saw plate thickness into consideration before. I had always assumed that all saw plates were very accurate and I never considered it as part of the equation. Everyone knows what happens when we assume!

Not wanting to look worse than I felt after realizing I totally missed saw plate tolerance as an issue, I decided to ask this person a question. “What kind of tolerances are people getting?” I asked. “Well, I have seen +/- 0.002 inches,” was the answer back. I was stunned by the answer as it was far more than I was expecting. I became gravely concerned about the ramifications of this piece of information.

Sawmills are trying to maintain a 0.0015” gap between their saw plate and their babbitt pad, but some mills have a saw plate that varies +/- 0.002”. This could cause some pretty big problems. As I mentioned in the first paragraph, a sawmill will have issues if the gap begins to vary too much in either direction.

It’s now time to add one more dimension to this gap control issue. It is critical that you measure your saw plate, and not just your kerf, when a new batch of saws come in. It is equally important that you compare these new blades to the thickness of your existing saws and saw plate. You need to make sure that there is no significant variation between your existing batch and your new batch. If there is a variation, you will have trouble maintaining your gap, and therefore your sawmill will have both lumber quality and uptime issues.

I don’t know why there is so much variation in some of these saw plates, but it may, and I am only speculating here, be due to the need to reduce cost on saw blades. As I have mentioned in my blogs, “You get what you pay for!” When you opt for the cheapest option, the vendor who needs to make money, may compromise on the quality. A precision-made saw plate is more expensive than a less precise plate. This is logical. There is more work involved in making a precision plate. The money you save upfront on the less precise plate will cost your sawmill more money in downtime and poor quality lumber. The overall cost is exponentially higher than the initial savings of the cheap saw plate.

It’s amazing how much I am always learning about the sawmill industry, and how surprises like this seem to come my way every day. I hope that those of you who are receiving saws make sure that you are specifying, and getting, the best quality saw plate possible. A variation of +/- 0.002” is going to cause the mill a lot of problems. These days where lumber prices are not the best, productivity and quality are paramount to your mill’s success. It can easily be the difference between a mill that is running and a mill that is shut down.


Udo Jahn is a general manager at Modern Engineering.
Oct. 13, 2016 - If you have worked in a sawmill for any length of time, then you have seen it happen many times. The saws are running great, the mill is producing and everybody is happy. Then all of a sudden, the saws start wandering, or there is a wreck, and then another wreck. Nobody is too worried at first, these things happen right?
It is a sawmill after all and wrecks are going to happen if you are pushing the envelope. But it doesn’t stop. One wreck turns into 12 and before you know it, stocks are dwindling, downtime is adding up and tempers are running short. Nobody has been able to figure out what is going on so inevitably, the finger pointing begins.  

Laying the blame on someone else is human nature. Since the problem is wrecking saws, the logical first step is to look to the filers for answers. Now I’m the first guy to admit that saw filers have a reputation for being a little prickly when it comes to being criticized. We work very hard within precise parameters to make our saws as perfect as they can be and having somebody say they aren’t working properly is like having your child berated by a stranger. That’s why it’s important for non-filers to remember that saws have no moving parts.

The statement “saws have no moving parts” seems a bit too obvious to actually be meaningful dialogue on a complicated concept but in fact, it says something important. It says, “If the saws are running well when they go on, they will continue to run well until acted upon by an outside force or they get dull.” It is impossible to bench a saw in such a way that it will run great for two hours and then suddenly fail of it’s own volition. Something had to change, either the saw got dull early (that’s possible) or the wood wasn’t delivered through the saw correctly due to a machine or operator issue. If you take that simple statement as fact, then you have narrowed down your troubleshooting dramatically. 

There are two things you have to remember about saw filers.  

No. 1: We are creatures of habit, we do the same things in the same order looking for the same result, every single time. Occasionally we will try an experiment, which may or may not work but we abandon such endeavours at the first sign of failure. We would never purposely cause extensive downtime and cost to try and make an improvement. 

No. 2: Saw filers are basically lazy. The better our saws run, the less work we have to do. We work extra hard to make sure the saws will work for the full run so we don’t have to go for early changes or worse, to clear a wreck.

That isn’t to say that it is never the saw filers fault. For example, it is possible that the saw wasn’t as sharp as it should have been. Saw fitters are professionals and take pride in their saws being sharp as razors but sometimes an undiagnosed problem with the sharpening machine or an inattentive eye allows saws onto the floor duller than they should be. When there is a problem in the mill, this is one of the first things a head filer will check. If there is an issue, it will be found immediately under closer scrutiny. 

The point I’m trying to make here is not that saw filers are perfect, or that they do it right every time. We aren’t and we don’t. What I am trying to say is that when things are going well and then suddenly go south, it isn’t because the benchman suddenly started benching differently after 25 years of predictable work. Finger pointing is a waste of time and a failure to funnel energies into fixing the actual problem. It is also a source of workplace disharmony, often resulting in rifts between departments that are difficult to heal.

If the saws run great at the beginning of the shift and then fail before the end of their scheduled run then by all means look for the problem but do it from the first wreck, not the tenth. Look to your filers as a wealth of information as to how the saw centres work as a balanced whole because chances are, they have seen this problem before. Remember, saw filers are very protective with their saws, if there is a problem in the mill they watch very carefully and may have theories you haven’t thought of. But don’t just blame the filers and hope that the problem goes away, nothing positive can come from that approach. We are here to work with you, not against you, and remember: “saws have no moving parts.”


Trevor Shpeley is the head filer for Tolko’s Kelowna division and is currently the financial secretary for the BC Saw Filers Association.
March 31, 2017 - Wrecks, we all have them. We hate them and we wish they would never happen but sadly, they always have and always will. We can’t stop them completely but we can work to minimize our catastrophic failures and maximize the safety of the workers who have to get in and clear out the tangled, unpredictable razor-tipped steel that is all that remains of what were once productive saws.


The first thing you have to consider in any upset condition is safety. Saws by their nature, especially bandsaws, store energy when they are pulled and stretched and torn apart. Even though everything seems stable when you approach the machine, very often the saw is held back like a coiled spring waiting to explode upon the people who are trying to clear it. I was involved in one such incident dealing with a broken saw in a quad bandmill. My partner was on one side reaching in through the guards to stabilize the saw while I was on the other working on freeing the saw from the wheel. I had no sooner brought the torn end of the bandsaw from behind the guard when the saw flew from my hand and rocketed across the bandmill to the other side where it coiled into a tight ball. If the saw had come towards me I would have been badly injured. If my partner had been more inside the mill, he would have been badly injured. It was so fast and so powerful that neither of us could do anything to stop it and we were both well experienced in clearing seriously wrecked saws. You can never really know what a saw is going to do so you have to minimize your exposure to risk and whenever possible use artificial means to cause the saw to release it’s energy in as harmless a fashion as you can manage.

Clearing wrecks should never be attempted by anybody who doesn’t know exactly what they are doing. One person should take control of the scene and perform an inspection before anybody goes anywhere near the saw. Under no circumstances should anybody start opening guards or grabbing saws before the designated leader develops a strategy and relays his plan to the rest of the team. From that point, everybody follows the order of the person in charge unless they can see that doing so would put themselves or somebody else in danger. If that happens, the team leader will reassess and change the plan accordingly. Never go off on your own and do something the others don’t expect. Safety depends on no surprises. Apprentices should stand off to the side to watch and learn before they are ever allowed to go in and help.

Preventing wrecks in the first place is the safest course of all and sawfilers can do their part by observing the machines in regular operation and training their eyes to quickly recognize abnormal behaviour. Even if they don’t know exactly what the problem is they can relay their observations to maintenance personal. Sometimes mere observation isn’t going to cut it and the sawfiler will have to determine what the problem is by examining the damage to the saws and watching video of wrecks and near-wrecks to track down the issue. Any problem you can spot when it is small before it becomes a wreck is a win for safety, production and saw-cost.

We all know that environmental conditions play a part in saw-loss. Winter for many mills means a ramp-up in saw-usage and although we all know that slowing things down would be beneficial for preventing wrecks, we also know that mills have to make money or we are all out of a job. The tug-o-war between people who watch the bottom line and people who want the mill to run smoothly has been going on for as long as sawmills have been in existence. The answer lies somewhere in the middle ground and usually by February, the working parameters for that season have been figured out and the problem goes away until the cold comes again in the fall.

We are always going to destroy saws. The demands we place upon them pretty much guarantee that. All we can do is keep our mills as perfectly aligned as possible, bench our saws to the highest standards and perform as much preventative maintenance as time and money will allow. Safety first so be careful out there, the saws bite.


Trevor Shpeley is on the executive of the BC Sawfilers Association and works as a filer at Kalesnikoff Lumber in British Columbia.
Feb. 13, 2017 - For as long as mill workers have been running wood through saws we have understood the importance of having every part of the machine positioned at exactly the right pre-determined location and angle to facilitate the smooth passage of the log and the straightest cut possible. A very small change in the inclination of a roll can mean the difference between a good day and a disaster. A slightly off angled saw will heat up and destroy itself in short order.


There are many different types of saw-centres out there, but lucky for us, you don’t need to know how to do every one as long as you understand the basic principle of alignment, which is to pick a level or vertical surface that is immobile as a base point (datum) and make everything else plumb, level and square to that. Most mills have fixed points in their sawlines for attaching tautly strung piano wire to serve that purpose; others use guide bars or optical lines for the same thing. It doesn’t really matter as long as it doesn’t move. 

It is important to remember that not everything is to be level or square. Some parts are toed in or out, some rolls are canted forward or back but these exceptions are well known and mostly hold true from machine to machine.

The tools needed for a proper alignment can be costly or very cheap. The expensive tools give you the capability for improved accuracy, but you can absolutely do a very good alignment with a minimum investment in equipment. The most common methods of alignment used in mills today are the “wire method”, lasers and optical jig-transits.

The wire method involves stretching a length of piano wire from one end of the machine to the other, parallel to the wood flow, typically right down the centre of the profile, spline or sharp chain. The wire is made as tight as possible to minimize the possibility of movement. Other lines are strung at 90 degrees to the first wire where needed. This technique is tried and true. The downside is that the act of measuring against the wire sometimes changes the measurement and when 0.002 of an inch is a large number, it doesn’t take much of a push to get that much of an error.

Laser alignments are another popular method. A laser is directed through the machine and through mirrors and prisms to achieve the desired angles. Then a detector is used to measure the relationship between the equipment and the beam of light. Lasers are very accurate and many swear by them. 

The other procedure gaining strength in recent years is to use an optical jig-transit, a device originally used for the very precise alignments required in the aerospace industry. The advantage of optical alignment is extreme accuracy. It allows you to take very precise measurements of every component in your line horizontally as well as vertically and it works over long distances. Difficult to measure objects such as the angle of spike rolls are easily determined and you can quickly check a press roll through its entire arc of travel. The disadvantages? It’s a pricey piece of gear and somewhat delicate. It requires a practiced skill level to setup and a non-running mill due to vibration interference. Is it worth the money given that? For me the answer is yes, but then, I don’t write the cheques.

Unfortunately for the sawmill industry, alignments have dropped out of favour somewhat. Everybody knows they are a good idea and yet they don’t get done nearly as often as they should. In some mills “rarely” is optimistic. There are many reasons for that. One is inter-trade rivalry in which one group claims mechanical control over a piece of equipment and won’t let the sawfilers “on their turf” to do the job. Another problem is that some management does not fully understand the importance of a properly aligned machine and work on the principle of “If it ain’t broke, don’t fix it”. The bottom line is, make everything straight and you will make better lumber and spend less time fixing broken equipment.


Trevor Shpeley is on the executive of the BC Sawfilers Association and works as a filer at Kalesnikoff Lumber in British Columbia.
June 21, 2016 - When it comes to saw filing, definitive rules are hard to come by. What works for one saw filer might be a disaster for another. If you have two mills from the same company manufacturing the same products with similar equipment, the natural assumption from mill managers and purchasing agents is that standardization should be possible and profitable – and sometimes it is. But more often than not, the success of the first mill can be difficult to duplicate in another.

The problem with attempting uniformity between sawmills is that every combination of machinery, employees, wood diet and environmental conditions produces a different animal. The same can be said for saw filers. How a person sees light and shadow, how tall they are, their physical strength, their experience, and even how they hold their hammer, will all affect how that person works a saw and what the end result will be.

Sure, there are basic standards within the trade that you can reasonably expect to be consistent – tire-lines will be more or less where you expect them to be; saws will be as level as possible and tension will be the correct amount to run properly for the application. But here’s the rub, it’s how the combination comes together that is more important than what each individual component looks like, and that is controlled by the experience and preferences of the filer.

For example, a question that gets asked often is, “Why do they all have their own saws? Aren’t they doing them all the same? Shouldn’t they be able to have ‘common’ saws?” The simple answer is, “No, not usually.” Whenever circumstances force filers to work each other’s saws the result is seldom ideal. Cracks appear in saws that have never cracked and benchmen are heard grumbling about how their saws have been changed by the other benchman. Theoretically, they haven’t been changed at all since they all have the same target, but in reality, small changes in a balanced pattern can have large consequences.

One of the variants is in how a filer gauges tension. In a bandsaw for instance, the two most popular methods are “light gap” and “black to the gauge.” In the first, the saw gauge is ground so that when held to the saw, a thin sliver of light shows from edge to edge and the filer uses that gap to tell if the tension is uniform and that the amount is appropriate. A small amount of pressure is then applied to the gauge and if all is well then everything would go black. Most benchmen use this method but it is subjective to the way a benchman holds his gauge, the pressure that is applied, etc. The filer gets used to seeing what he expects to see in a properly benched saw. Someone else may view the same saw differently.

Other filers prefer to use a tension gauge that is ground to the curvature of the desired tension. When the saw has been levelled, the filer looks for no light between the tires when the gauge is held against the saw. The disadvantage to this method is bumps and tension problems can masquerade as “perfect” if a benchman isn’t very careful with what they’re doing. The black-out method is more often used by very experienced filers.  Again, the angle of the gauge, the pressure applied, all change the sight picture for different filers. Is there a right way and a wrong way? To a certain extent, yes - you can’t just do whatever you like and expect a positive result - but a filer that is confident in his chosen method will produce a better product every time.

When it comes to levelling, I myself prefer to use levelling rolls whenever practical. I believe that it does less damage to the saws, produces less filer-created bumps and is faster. My colleague, who is an excellent benchman, prefers the hammer. He isn’t wrong and neither am I, both methods work and the saws look a little different afterwards but everything runs and it runs properly. Metcalf vs diamond dresser, this brand of saw vs that, a V-gauge vs an RPM gauge, the list goes on and on…

The bottom line is that there is no bottom line. A saw has been done properly when a filer has put all of his/her knowledge and skill into the task and the saw subsequently performs properly for the full length of its run. Almost every filer will produce a different looking saw from one done by an equally skilled co-worker but they will usually run uniformly. That’s the beauty of saw filing.


Trevor Shpeley is the head filer for Tolko’s Kelowna division and is currently the financial secretary for the BC Saw Filers Association.
Aug. 16, 2016 - On the surface, levelling a saw sounds pretty simple. You just put a straight edge against the saw with a light behind it and look for a dark spot. Then you hit it with a hammer until it is gone. In reality, levelling a saw is very difficult to learn and perform properly.



One of the reasons levelling is so important is that everything else is dependent upon the saw being perfectly flat. That means no twist, no cupping or bowing, no ridges and especially, no bumps. Any bump bigger than .001 of an inch needs to be removed before any tensioning, sharpening or tipping can take place.

So why is levelling so hard to learn? Let’s go back to the basic mechanics of the task. You take a piece of steel that you have ground perfectly straight on a specialized grinder and you place it on the saw between yourself and a light. Bumps will show up as a black spot along the bottom of your straightedge, so will tension. In fact, tension can look exactly like a bump. If the tension is too heavy or unevenly distributed, the saw will want to cup or bow making levelling the saw almost impossible.

 To complicate matters, a saw has two faces and bumps will appear on both. The saw filer will use levers and other homemade devices to push a dent out from the bottom of the saw or they will climb down into “the pit” to level the inside of a saw directly. The round saw filer will just flip the saw from side to side until everything is smooth. It would be nice if you could just flatten all the bumps you could find in one area and then go on to the next but when that is attempted you will bow or dish the saw by over-levelling. The trick is to hit the worst bumps all around the saw and keep going over and over until the saw is flat.

If you fail to get the saw perfectly level before performing the rest of the benching procedure, you will never get the saws to run right. A small bump can hold up the tension so that it looks like you need to add more. After you do that and put the saw in the run, typically the bump will “pop” and suddenly your saw will be all over the place due to the massive amount of tension you put in when you thought there wasn’t enough. It is also common to put bumps into the underside of the saw by hitting them too hard while trying to remove the ones on your side. A trained hand and a delicate touch is required to level a saw without creating new problems.

The most common levelling method is to use a hammer to pound out the bumps. Hammers come in different weights and styles of head shape for different sizes of saws and types of defects. The levelling is done on a soft anvil so that the squishing of the saw between the anvil and the hammer is minimized in order to avoid adding more tension to the saw during the levelling process. Hammers work well and a skilled saw filer can do wonders with a good one but many benchmen eventually graduate to doing most of their band saw levelling with stretcher rolls.

Rolls have the advantage over hammers in that you can do a lot of heavy levelling without adding any tension or causing any bumps on the reverse side of the saw. It is also much easier to remove twist and ridges with the use of rolls and you don’t get that “peened” look you get from heavy hammer work. There are still areas where hammers are definitely the best tool for the job but most band saw levelling can be done more effectively with the use of rolls. In round saws, rolls are the best for removing ridges or fixing a dished saw but hammers still play a very large part in the circular world.

Several manufacturers now produce very fine auto-levelling machines. Some are more complicated than others but most have one thing in common: they do the job of levelling a saw very well – these are not your grandfather’s auto-levellers! The newer generation machines do the job with no drama and minimal tinkering between saws. Choosing which leveller to buy can be tricky as they have different scanners and methods for removing defects and the price can vary widely. But if you do your homework, you can be sure of getting a decent tool that can take the grunt-work out of levelling saws.

In the end, it doesn’t matter what you use to level your saws as long as they are level.  No matter how good you are at every other aspect of the job, if you can’t get your saws perfectly flat then you are just spinning your wheels. When you get it right though, everything else gets a whole lot easier!


Trevor Shpeley is the head filer for Tolko’s Kelowna division and is currently the financial secretary for the BC Saw Filers Association.
Feb. 9, 2015 - Simonds International Market Manager Russell Barratt provides his insight on the concerns in the Canadian forest market during anexclusive interview on the floor of the Timber Processing and Energy Expo.
Jan. 30, 2014 - On behalf of The BC Saw Filer's association executive I am pleased to invite you to our upcoming conference in Kamloops, BC April 25-26, 2014 at the Coast Kamloops Hotel and Conference Centre. There will be a trade show on Friday April 25th from noon until 7pm. On Saturday the 26th we will be conducting our annual AGM, have a key note speaker, have educational presentations and an open forum discussion to discuss relevant current issues.

We will be having a banquet and awards dinner on Saturday night which will be open to all who attended the trade show and their spouses/companions. We will have more information on the cost for attending the banquet in following newsletters. Registration will be available on site on both Friday and Saturday.

Membership dues will remain the same this year at 20.00 for our filer's and our associate members (suppliers). If you cannot make it to our conference please send your information/check with someone to our conference or mail to me at 6521 Orchard Hill Rd, Vernon, BC, V1H 1B6. Please make check payable to our association. We will be sending out a detailed agenda once we have all the details worked out.

This conference is open to mill managers, maintenance supervisors, and all saw filers.

We have rooms blocked off at the Coast Kamloops. Reservations can be made by calling1-800-663-1144 using group code "CKH-GFC1368" or the meeting name "BC Saw Filer's". Cutoff date for rooms blocked off is March 24, 2014.
As your executive we are building off of the success we have experienced the past couple of years. Thanks to all our members, the sponsoring companies and our suppliers for the commitment shown to make our last conference as success. We are excited about the upcoming conference and would appreciate your continued support.

Our trade school is up and running with a couple of classes going to be completed prior to Christmas. The class in February for second year filer apprentices has been cancelled for the time being due to lack of registration. If you have any questions about exact dates and space availability please contact TRU. Please get the message out so we can fill this class up and solidify our position of training our apprentices.

If you have any questions please feel free to contact me.

Thanks,

Bruce Doroshuk
President, B.C. Saw Filer's Association
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Work: 250-546-2234
Stay Safe, Stay Sharp
Aug. 20, 2007 - Getting the most from your bandsaw leveler requires doing a few basic things correctly, and ensuring that the machine is properly aligned.  Some key things don’t seem logical at first glance, but do indeed make sense when we look a little deeper. Let’s look at both daily operational tactics, and some common set-up problems to look at when things don’t seem to be working.


Daily Operation
Three things are important in the everyday operation of a bandsaw leveler: Where you get your reference “zero”; how you get your reference “zero”; and how you move across the saw.  It’s not surprising that establishing “zero” accounts for two of the three points. Without a proper “zero”, all bets are off.  Let’s look at these one at a time:


• Get “zero” over the saw support rails (figure 1):  Your leveler is intended to put the saw flat, meaning on a plane. The only plane available is the one established by the top surface of the carbide rails, so the only place you can get zero is directly over those rails.  It’s okay to work on the saw out past the rails, but if you establish your zero reference someplace besides the rails you will likely be telling the machine to move the saw to a plane that the rails make it impossible to reach, unless the saw is perfectly flat to begin with! This will cause ridges over and adjacent to the rails.  




• Get “zero” on the fly:  Equally important in establishing zero is having the saw moving.  This will prevent accidentally setting zero on a bump, which will again have the machine trying to move the saw up to the plane of that bump, a place the saw cannot possibly reach.  When getting your zero this way you should look for your indicator (or sensor) to work from zero UP only, because a bump DOWN cannot move past the rail.  On the machines that use indicators (the pretty red machines!) this means the indicator will work from “0” to the right only, and will not move left of “0” unless you run over a thin spot like a weld.


• Take big steps: One of the important counter-intuitive things we have learned is that it’s vital to take big steps across the saw. If you take small steps, the machine will routinely start seeing bends before it reaches the worst part of the bend. It will then start trying to fix the bend too soon, and overwork the saw.  This will cause a saw in rough condition to end up with hard ridges the machine has actually pushed into the saw – these are hard to get out again, and will waste time.  


The worse shape a saw is in, the bigger the steps you need to take moving across it. For instance, if a saw is dished, set your machine to make a couple of passes at 1" or 1-1/4" spacing to get the dish out, then dial it back to 1/2" and let it have another couple of passes to find the little stuff. You’ll save lots of time and get superior results.  Don’t get caught in the “I really want a flat saw, so I’ll set it for 1/8" advance” trap!  Never set your machine for less than 3/8" or 1/2" advance, and if it’s in tough shape open that up to 1" or more and you will get better saws in less time!


Common Set-Up Problems
If after the above you are not getting the results you need, take a look at some of the basic set-up points on your machine.  A good place to start is checking that you are set to fire at the same tolerance on both sides of zero. We set our machines up to fire the first stage reaction at ± .03mm each side of zero. This is three marks on the face of the dial indicators that we use, and is equal to .0012" (one point two thousandths of an inch!).  This is quite a small tolerance – a piece of notebook paper is about 2-1/2 times this dimension. Setting the tolerance closer will not improve leveling, and may cause the machine to simply shove the saw back and forth.  


The second stage on our indicators is usually set at ± .12mm, which is about .005" and is the point where the machine will add pressure for a bump that is worse than this. It is not terribly critical that this 12 mark second stage is exactly the same both sides of zero. Within a couple marks is fine, but the 3 mark (.03mm) first stage needs to be the same both sides (within 1/2 mark).


Now check that you are leveling as close to the gullets and edge of the saw as possible. Set your limit switches so that you move the large diameter flat on the outside of the female roll over the bottom of the gullet, or the sliver tooth or back edge of the saw. This will get you out close to the edges without damaging the indicator.




Another key is getting the height of the bottom leveling rolls correct in relation to the bed line of the machine (established by the plane of the saw support rails and the drive).  The bottom leveling rolls must be at or just barely below this line (no more than .010" lower).  If the rolls are too high, they’ll lift the saw as they move across during processing, changing the measurements. If the bottom rolls are too low when the top rolls fire, they will drive the saw down, breaking the saw over the leading edge of the saw support rails and causing the tension to pop up (figure 2). If you have to adjust these bottom rolls be sure that you turn them the correct direction to keep their eccentrics mated with their top rolls.  On the left hand roll turn it clockwise to raise it (counter-clockwise to lower it), but on the right hand roll do the opposite – turn counter-clockwise to raise it, and clockwise to lower it.


Worn drive rolls can also cause tight ridges that coincide with the edges of the rolls.  This will start to show up after the machine has many hours of service, but these ridges can be very difficult to get out.  It’s a result of the change in diameter of the drive parts from normal wear, which causes them to become miss-aligned.  When they wear enough for their centre-lines to shift apart a bit, they will start to work like a panning roll, but always bending exactly the same place in the saw, creating small hard ridges.  If these parts wear – replace them. If your machine has a steel top drive, replace it with the newer polyurethane replacement, which will last virtually forever.  


If you have checked all of the maintenance and operating items thus far and still are not satisfied with the results, it’s time to look at how the saw support rails are aligned with each other, and how the head moves in relation to these rails.


The two carbide-faced saw support rails must be flat and they must be set up with their top surfaces parallel to each other. Check for flatness by pivoting the hold down rolls out of the way and laying a good straightedge on the full length of the rail.  If wear is evident, get the rails surfaced or replaced. Now use a depth micrometer to measure from the top of each rail down to the plate that supports them on both the leading edge and the trailing edge (as close to the head as possible and as far from it as possible) and adjust the rails until they are parallel.  These four measurements should all be within .001" – .002" of each other.


Once you are certain that these rails are parallel, you need to establish that the workhead is moving parallel to the plane of these rails.  An easy and very accurate way to do this is by mounting a magnetic base dial indicator on the workhead of the machine, resting the point of the indicator on a straightedge laid across the rails, then running the head in and out to verify that the indicator reads the same on both rails and between them (figure 3).  If you find that the indicator is off more than .005" over the working width of the saw, shim the entire support mechanism that holds the rails in place until you get that movement down to within that five thou.




One important note – don’t let bent teeth confuse you when it comes to what the leveler is doing.  The levelers are indispensable tools, but they cannot level the teeth themselves.  If you see problems in the front quarter of your saws after they come off the leveler, make sure it’s not a result of bent teeth.  Move your saw so that the whole tooth is off the anvil. Does that make the problem vanish?  If so, the teeth are bent down! Move your straightedge back so that it is not resting on the tooth at all. Does that make the problem vanish? If so, your teeth are bent up! You can verify this using your leveler. With the mach­ine stopped, move the indicator right out onto several teeth in the suspect area, one at a time. The indicator will tell you very quickly if the teeth are bent in either direction. You can’t level out that far, but with the saw stationary you can use the leveler to measure.


There are lots of other ways that the operation of a leveler can be impacted by worn parts or bad set up, but the ones outlined above are a solid beginning based on our experience with these machines.  If you go through these steps and still need help, contact the firm that supplied your machine, and they will be eager to help get you running right.


Russell Barratt is a sawfiling specialist with Simonds International, based out of wherever saws are being doctored. He has been involved in filing and sawmill gear for 27 years. This is the third in a series he has written exclusively for Canadian Wood Products Magazine.
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