Through the years I have dulled a lot of bandsaw blades on my sawmill, and for the longest time, I have struggled with keeping them sharp. I have tried multiple tools and methods to get this done, but only within the last year do I feel like I have found a good solution.
The problem starts with the bandsaw blade itself. It is a finicky conglomeration of bent teeth, cut from a thin piece of flexible steel that is somehow supposed to cut a straight line, not only from front to back, but also side to side, and if it isn’t well machined and sharp, there isn’t a snowball’s chance that this is going to happen.
Early in my career, when a new saw blade dulled and started to cut waves, I would try things like adding tension to the blade, slowing down my feed rate or even adjusting my blade guides. No matter what I tried, a dull blade would still make a wavy cut. However, if I used the exact same setup but installed a new blade, the cut would be perfect again. As a matter of fact, almost every other adjustment could be less than perfect and a sharp blade would still make a good cut. From 15 years of experience, it is clear that I need to keep my saw blade sharp and touch nothing else.
My standard course of action is to put on a new or newly sharpened blade from Wood-Mizer when my cut starts getting wavy. This is a great way to live. Nothing cuts like a brand new blade, and it feels like a treat to put one on. Even the resharpened blades cut great since they get a complete factory treatment, including cleaning and full tooth grinding and setting. I have always had great results from Wood-Mizer, and I highly recommend their new blades and resharpening service. (Disclaimer: I am not being paid by Wood-Mizer and Wood-Mizer doesn’t know I’m writing this post – they probably don’t even know I exist.)
The problem for me was that time in between cutting like new and cutting like crap. I would have a blade that was cutting great, but I could feel it pulling hard and on the verge of cutting poorly. I didn’t want to pull it off of the saw because it was running so well, but at the same time I knew my time was limited. If I could just get an edge back, I could keep cutting with the same blade and not have to mess with sending the blade off to be sharpened, and I would save $7 (by the way, I think $7 is a great price for the quality of service, but I would rather not spend it if I don’t have to). So, off I went, looking for a way to sharpen blades on my own.
In the past, I tried using a manual sharpener that came with my first bandsaw mill. It functioned like it was designed to, but the results weren’t great. Besides having to take the blade off of the mill and set it up in the sharpener, it used a stone that wore down quickly and wouldn’t maintain a flat, consistent face on the tooth (looking back, I probably should have tried some other stone options, but I didn’t).
Later, I tried a few other approaches. The first was using my chainsaw grinder, like the one below, which had a similar problem to the first grinder. The small stones would wear down quickly and the thin bandsaw blade would basically cut the stones in half.
The next attempt used a sanding disc on a drill. I liked the idea of using sandpaper because it maintained a flat surface during grinding – it would wear down, but not change shape. This one showed potential, but it was incredibly hard to control because the spinning motion pulled the drill up and away from the blade.
I finally gave up, feeling like I had exhausted every option cheaper than buying a fully automatic grinder like the factory has, but I never gave up on the idea of sandpaper as a good abrasive that doesn’t change shape.
Up to that point, all of my attempts focused on sharpening the saw by grinding the front of the tooth. There was nothing else I could think of that would fit between the teeth and grind the front of them. But, then I thought about grinding the top of the teeth. This surface is easier to get to and taking material off of the top will still lead to a sharp point – it doesn’t really matter which face gets ground down.
I started off with my 3″ Porter-Cable belt sander just to try things out and it worked great. I could sand the top edge of the tooth with control and the speed was slow enough to not feel like I was burning the metal (which softens the teeth). The only problem was the weight of the belt sander, which might as well have been 1,000 lbs. because there was no way I could hold it to sharpen all of the teeth on the blade.
At the time I didn’t own a small belt sander, so I took a gamble and purchased a Porter-Cable 371 compact belt sander. I figured that even if it didn’t work for the blade sharpening I would at least have another tool in my woodworking arsenal and that there were going to be plenty of times when a small belt sander would come in handy. Finding other uses for the new sander hasn’t been much of an issue though, because it works great to sharpen blades, and it is always parked (plugged in) right next to my saw, ready for the next dull one to come along.
I simply leave the blade on the saw and grind just enough off of the top of each tooth to get the edge back. I use my free hand to steady the blade and to advance the saw to the next tooth. In a matter of just a few minutes I can be back to cutting, feeling like I have beat the system.
Now, there are limits to sharpening your saw like this. First off, no matter how good you get with the sander, the blade will not be as good as a new one or one that has had a full factory grind and set because this grinding is changing the geometry of the already finicky blade. And, it will do nothing to improve a blade that was just generally running badly or running badly for a specific reason like hitting a rock or metal (all of these problem blades get sent out for a full resharpening). It will, however, make a blade that was running well continue to run well and make flat, straight cuts for much longer.
Generally, it seems to work out that I touch up a blade with the sander a time or two and then send it out for full service or, for some of them, they keep working great and I keep sharpening them with the sander until they break. For all of the others, I hit something along the way (dirt, rocks, concrete, nails, hooks, cable, wire, screw-eyes, barbed wire, fence posts, screws, license plates, horseshoes, railroad spikes, chain, conduit, hangers) that either destroys the blade or dulls it enough that it needs a full regrind.
Even if I don’t use this method all of the time, it is nice to have another option to get back to cutting. If nothing else, I personally love the comfort of knowing that when I get down to my last new blade (and forgot for the second week in a row to order new ones) that I won’t be stuck cutting wavy lumber.
If you have driven down Highway 40 in St. Louis recently, you may have noticed a new structure being erected next to the St. Louis Science Center where the “temporary” Exploradome once stood. After 16 years in service, the inflated building was past its prime and too expensive to operate, so it was replaced with a new, permanent agriculture exhibit called Grow.
The centerpiece of the exhibit is the new building that features massive bent laminated beams which create a beautiful swoosh of a roof. Just outside the entrance of the new building is a vermiculture display that I built for the exhibit. While it pales in comparison to the woodwork that went into making the building, I like to think it makes a nice little earth-friendly welcome mat for visitors.
The vermiculture unit, designed by Mark Cooley, uses worms to make compost. Built out of locally salvaged Eastern Red Cedar, the two-compartment structure is set up to have green waste loaded in the top and compost extracted from the bottom after the worms have done their job eating the contents. The two compartments, which are side by side, are divided by a wire mesh that allows the worms to move between compartments. This particular unit has glass panels to allow for viewing of the interior from the front of the display, though the glass is not required for use.
This project was a bit out of the norm for me since it was more carpentry than fine woodworking, but it was a fun change to build something that wasn’t so fussy. I had the most fun when I was able to find some logs in my shop already standing against the wall for the project. They were left over from another project, and I was able to just carry them to the sawmill and cut the parts I needed. I chuckled to myself while I was doing it because I have never just hand carried logs to the sawmill that were standing in the shop like sticks of lumber. It was only possible because cedar is lightweight and the logs were small, but I still had more than enough to make this project.
Cedar mills like butter on the sawmill, even when dry, and since it was going outside I didn’t need to do any extra drying. I was able to mill it, plane it and assemble it right away, which made it feel more like I was building a fort or a treehouse, especially since I never get to knock something out like that. It reminded me a lot of the Mermaid Lagoon sign I made for Mira a few years ago, since both went together expeditiously. There were a few critical measurements to maintain, like the size of the footprint, but everything else was somewhat negotiable as long as it looked and worked like Mark Cooley’s design.
The vermiculture unit is nestled in the Grow exhibit along a mulch path surrounded by plantings that are arranged like a garden or small farm field. Nearby are live chickens, two new tractors, a greenhouse and a dairy demonstration area. Inside the building are electronic, hands-on displays that focus more on the places that generate food, from the species of plants to different farm settings. Outside, on the North side of the building, are a couple of displays that focus on water, with a chance for the kids to interact with displays that are both hands-on and hands-wet.
The St. Louis Science Center and the new Grow exhibit are free to all visitors. It opens Monday-Saturday at 9:30 a.m. and Sunday at 11:00 a.m. The Science Center closes at 5:30 p.m. during peak summer hours (May 28-Sep. 5, 2016) and at 4:30 p.m. during off-peak hours.
In the normal course of my business, I am sometimes asked to make flooring out of my customers’ logs. Because I mill the logs into random width boards, I would often get stuck with trying to determine the best width to make the flooring, knowing that no single width would have that great of a yield. No matter the width I chose, there would always be plenty of boards with lots of waste. If I chose 3″ wide flooring, I can guarantee you that an astonishing number of the rough cut boards would just happen to measure 8-3/4″ wide, which would yield two 3″ wide boards and one wide scrap piece, absolutely killing me.
In the past, I have tried to decide the width ahead of milling the logs and pick out which cut was going to be flooring and which was going to be another product, like siding. It seemed simple enough, if the board I was cutting was long and clear with no knot holes, I would cut siding, and if it was knotty and was going to produce only short pieces that were good, I would cut them for flooring. All I really had to do was sort the lumber into two piles while I was working. But, it wasn’t that easy.
Some logs would have a side that was good for producing siding, but the next side was only good for flooring. When I flipped the log over to a new side, my width was determined by how much I cut off of the last side, and it was always random. So, no matter what I did, even if I was cutting for a specific product, I would get stuck with lots of random width boards.
As I mentioned, wasting lumber kills me, and every time I ripped random-width boards down to some set width, leaving wide scraps on the floor, I thought about how to stop wasting so much wood – then it clicked. Many years ago, a friend of mine showed me a floor he made for his own house out of random width boards. As far as I know, he only did it because he thought it would look different and make his house have a special touch that would only come from someone who made their own flooring. His floor was white oak with tons of character, in three different widths. It was beautiful, and it seemed to me that I could use these random widths in some form to stop wasting wood.
I don’t remember a specific moment when I had the epiphany (though I am sure I must have had one), but I figured out that using just three widths, 3″, 4″, and 5″ would cover every width of board I could produce and always leave me with less than 1″ of waste per board.
Think about it. 3″, 4″, and 5″ wide, rough lumber is covered right off of the bat since they are already useable widths. After that is a 6″ wide board, which will just be ripped into two 3″ wide strips. A 7″ board gets ripped to a 3″ and a 4″ strip, while an 8″ board turns into two 4″ strips or a 5″ and a 3″, whichever is preferred. Any width of rough lumber over 6″ wide can be broken down in some way with just the three target widths of 3″, 4″ and 5″. By the way, these are the rough cut widths. The finished tongue and groove flooring will end up with a face about 1/2″ less in width.
Random width flooring looks different, but not too different. At first glance, the viewer only notices the beautiful wood, and then after closer inspection notices the three widths, which lets them know subconsciously that the flooring is special. It stands out because it isn’t all one width like typical hardwood flooring, and most people have never seen or even thought of using random-width flooring. But, I say, “Don’t be scared of it.” It is different and not typical, but in a good way, especially when it comes to waste.
One of the first things I needed to figure out when I started cutting rough lumber on a sawmill was what thickness to make it. I could generally determine if I wanted it to be thick or thin, but just how thick or thin? 4/4 lumber is 1″ thick, so it should be rough cut at 1″ thick, right? Not exactly. For hardwoods, the commercial target for 4/4 lumber is actually 1-1/8″, which allows enough margin to produce dried and planed lumber at a thickness of 13/16″ or 3/4″ (3/4″ is acceptable, but the extra 1/16″ of thickness in 13/16″ material allows room for additional planing or sanding after panels or doors are glued up).
The crazy thing is that back then I couldn’t find solid information on lumber thicknesses anywhere and when I referred to the NHLA (National Hardwood Lumber Association) guide, the thicknesses didn’t match up with what I was finding from hardwood producers. The NHLA guide doesn’t include the bonus 1/8″ of thickness – 4/4 lumber, for example, is specified at a minimum of 1″.
In my experience, 4/4 hardwood lumber cut at 1″ is too thin to consistently produce flattened and planed lumber at 13/16″ thick and will even have trouble producing 3/4″ thick unless the boards are very flat. The only way 1″ thick rough-cut hardwood lumber can plane out completely to 13/16″ or 3/4″ thick is to skip the flattening and just plane the lumber. This will produce thicker finished lumber, but it won’t be flat and straight since the planer will simply follow the curves of any crooked boards. From a woodworkers perspective this is a horrible practice and makes woodworking much more difficult. For this reason, I cut my 4/4 hardwood lumber like all other quality producers at 1-1/8″ thick and don’t accept anything from other sawmills or wholesalers at 1″ thick.
Starting with the lumber measurement and adding 1/8″ for the final thickness is how all of the hardwood measurements go, with a target for 4/4 lumber at 1-1/8″, 5/4 lumber at 1-3/8″, 6/4 at 1-5/8″ and 8/4 at 2-1/8″. These are the commercially accepted numbers, and except for 8/4 lumber the ones that I shoot for. The problem with 8/4 lumber is that since there is more wood it shrinks more than thinner lumber and 2-1/8″ thick just isn’t enough thickness to flatten and plane lumber to consistently finish at 1-3/4″, which is the target for 8/4 lumber. When I flatten and plane batches of 8/4 lumber milled at 2-1/8″ thick it isn’t uncommon for half of the lumber to finish at 1-5/8″ thick instead of 1-3/4″.
Because I think 2-1/8″ is a little thin, I commonly cut 8/4 lumber at 2-3/8″ thick. 2-3/8″ thick is twice that of 4/4 lumber, plus the 1/8″ saw kerf that would have been between the two imaginary cuts. The extra thickness not only impresses the ladies, but it assures a final dried and planed thickness of at least 1-3/4″ and officially uses no extra wood when compared to cutting 4/4 lumber (to keep things simple, a friend of mine simply calls it “double four quarter” lumber). As I mentioned though, 8/4 is commercially sawn at 2-1/8″ thick, so if you cut it at that measurement it isn’t wrong, 2-3/8″ is just better for the end user (none of my customers have ever been upset that the wood is a little thicker).
The previous examples were for hardwoods, but softwoods, like white pine, can be cut thinner since they shrink less and dry straighter overall, plus softwoods are commonly used for construction purposes instead of furniture, which don’t need the extra thickness for secondary planing or sanding, so 3/4″ final thickness is common for 4/4 softwood lumber. For 4/4 white pine for example, I cut 1″ thick, which will finish at 3/4″. And, for cedar, which shrinks very little and is very straight and stable, I will go even thinner, down to 7/8″. In general though, softwoods are cut on the standard quarter scale with 4/4 lumber measuring 1″.
The scale below shows the target hardwood lumber thicknesses for commercially produced, rough-cut lumber and their planed thickness counterparts. These are the sizes you should expect to find when shopping for hardwoods.
Hardwood Lumber Measurements
Quarter-scale measurement Rough cut thickness Planed thickness
4/4 1-1/8″ 13/16″
5/4 1-3/8″ 1-1/16″
6/4 1-5/8″ 1-1/4″
8/4 2-1/8″ (or 2-3/8″*) 1-3/4″
*2-3/8″ is a better thickness to consistently finish at 1-3/4″ thick, but 2-1/8″ is the norm.
I have been on a sycamore kick lately, and this sycamore slice keeps my streak going. There are three stacks of these rough sawn slices for sale in my shop, and though I have sold a few, this is the first one to officially get finished and installed.
The slice is 3″ thick and is a cross cut of a 48″ diameter hollow sycamore log that had the added benefit of having a long open wound that didn’t quite seal up. In the tree’s attempt to close the wound the new wood took on a curl shape on both ends that make the slice look more like an artistic expression than just a hollow log.
Since the tree was standing dead all of the sapwood is consistently spalted and marbled in appearance. There is some solid heartwood in the piece which isn’t spalted, but has a beautiful rust color.
I was planning on ditching this tree since it was hollow and didn’t seem to have any millable lumber in it, but when I saw the curl shape on the inside of the log I did a u-turn on my way to the dump. Solid logs with complete centers that are sliced like this tend to crack and fall apart because of the drying stresses in the log, but in this case all of the drying stresses were relieved since the center was gone. When the outside wood wanted to shrink it wasn’t restricted by wood on the inside and could freely reduce in diameter without any problems.
I installed the slice on the wall with two lag screws, just like a mantel. I drilled matching holes on the back of the wood and just slid it on the wall (with the help of my customer). This system works great since it allows the piece to get flush to the wall and enables it to be removed without tools should the need arise.
Overall, I am ecstatic to have one of these completed and out the door. Next up is to finish at least one extra to keep in the shop to show off. You wouldn’t believe how much faster they sell with a finished sample around to seal the deal.
This week I picked up a sycamore log at Grant’s Farm for a local woodworker. He has been commissioned to build a round table from the tree that has stood on the property since the time of Ulysses S. Grant.
Because the log was too heavy to load in one piece and was going to be cut into round slices anyway, I cut it in half to make it easier to handle. The log is a minimum of 60″ in diameter on the skinny end, and should make a few nice table tops.
I jokingly complained to my wife that I drove all the way to Grant’s Farm only to pick up two 3′ long logs – that, by the way, filled up the truck.
Recently, I set up three large hollow spalted sycamore logs to cut in the Lucas mill. They are all in the 48″ diameter range and most were cut 3″ thick. I see future tabletops (with glass) and wall decorations. Out of all the logs I had on the lot, these were drawing the most attention, so they got cut first.