Making A Homemade Band Saw Homemade Machines & Jigs
In March, 2010, I started this project. Prior to this, I had been following Matthias Wandel’s band saw build (the first one) with interest and thought I would try to build my own. That is the way many projects start: a source of inspiration to spark the creative process, and it’s this and the collected know-how that make sites like Woodgears.ca so valuable.
I started with the frame. Having the ability to work metal, I wanted to make it from steel. Steel can produce a strong frame that isn’t overly bulky, if correctly made. I studied some commercial band saw designs, mainly for overall dimensions and structural details, and came up with the basic frame design.
The main support member for the frame is a piece of 2″ x 3″ thick walled rectangular tubing. This would be the post that runs vertically on the left side of the frame, and the rest of the frame components would be welded to this. This main support post provides the bulk of the strength to the frame, so it was important that it be of adequate size to resist the bending and twisting forces the frame would experience.
For the majority of the rest of the frame, I used thick walled 1″ x 1″ square tubing, salvaged from an old (rather large) garden trellis. The stock was in rough shape, with the main obstacle to using it the thick layers of paint that I would have to grind off:
A lot of work to clean it up but the benefits are twofold: I save money on raw material and I get rid of something that is no longer useful or attractive.
Seen here, the first frame member is clamped in place, ready to be welded:
Having all of the frame parts accurately placed is critical to the build. I’ve made a 90 degree clamping jig from plywood to hold the part perpendicular to the main post and used another piece of tubing to clamp it in line with the face of the post.
When welding parts together, I have to be mindful of the fact that the heat from the weld and shrinkage of the cooling weld will distort the metal, throwing it out of alignment. To avoid this, I tack weld the part in place on opposite sides of the joint, thereby minimizing this distortion. With the part tacked on all four sides, I can complete the weld, alternating from one side to the other and checking the alignment as I go.
The bottom part of the frame takes shape:
And with the addition of three more members, the lower frame is done. As ‘rustic’ as it looks, it is very strong and very accurately made.
Adding a metal ‘skin’ to the lower frame. This I’ve screwed in place with self drilling sheet metal screws. I don’t want to take the chance of distorting the frame by welding this skin in place. Again, I’m using recycled steel, this time the material is from window cut-outs on a heavy steel door:
Getting the upper part of the frame constructed. The bottom member is angled to reduce the free span of the main post slightly, and because it looks a bit better than square across. This angle doesn’t reduce overall cutting capacity, since the upper blade guide will hang below the member on the right side.
The flat bar in the middle is the upper wheel axle mount.
The skin added and the upper wheel mount finished.
This saw differs from most others, in that the blade tension is controlled by raising or lowering the lower wheel / motor assembly. The upper wheel is only responsible for tracking, and that is done by bending the flat steel bar that the axle is attached to forward and back, via a hand wheel at the back of the unit:
A hand wheel will be mounted to this shaft, to facilitate tracking. The mechanism is very simple – by bending the flat bar back, the axle shaft goes up off horizontal, pulling the upper wheel back out of vertical alignment and the blade tracks toward the rear of the wheel. By bending the bar ahead, the opposite happens, the wheel rotates forward out of vertical and the blade tracks forward.
Motor Subframe Assembly
The motor I wanted to use for this was one of the two treadmill motors that I bought at a surplus store. The other I used in my Disk Sander project. These are rated at 1 hp, and turn at 1725 rpm – very good for a band saw of this size. Although untested at this point, I thought it would be worth the risk of using this motor, since it was very low cost.
To mount the motor, I constructed a frame with a pivot, to allow the motor to swing up and down to tension the v-belt:
This frame was then attached to the main motor assembly subframe, seen here partially completed.
The upper section of the subframe supports the lower wheel drive mandrel. Seen here the unit is mostly complete, pulleys of the correct size have been mounted and the right length v-belt is installed:
Buoyed with confidence from doing such a splendid job, I powered it up, to check the performance. It was then that I realized that this motor turns counter clock wise and could not be reversed (all of the start winding wiring was inside the welded frame of the motor, making it impossible to rewire without cutting open the frame).
So, my options were to either turn the motor around (pointed out to my by Matthias Wandel, although too late at that time)
or get another motor, one that was reversible. Since these treadmill motors were still of unknown quality, I decided to get a new motor:
A new (on sale) 1 hp motor that I wired to run clock wise. I had to add a couple of pieces to the motor mount, but that was not much trouble. I also had to go with a shorter belt, since the new motor mounted higher on the subframe than the treadmill motor.
I then made a mounting frame for the subframe and bolted it to the frame of the saw (too many frames?). Between the mounting frame and the motor subframe assembly, I used drawer slides, to allow the motor assembly to move up and down to tension the blade. In hindsight, I can say that doing it this way was not really a good idea. Making the upper wheel move up and down to tension the blade would have been quite a bit easier:
The saw is now ready for wheels.
Speaking of wheels, I removed the motor subframe from the saw to ‘turn’ the wheels true and put a crown on them (I did the upper wheel this way as well). The wheels are made from 5/8″ melamine, with the rim thickened with a second layer to make the wheels 1-1/4″ thick. Although on the heavy side, these are very flat and stable:
With the frame complete, I gave it a paint job. This is a base coat of flat Tremclad rust paint (white) overcoated with water based clear satin polyurethane. The result is a very tough, durable finish. It makes quite a difference to the appearance, cleaning it up nicely.
The motor subframe assembly I painted flat black. Tremclad rust paint again, though this time in a spray can:
I fashioned a belt and pulley cover from sheet metal and screwed it in place. This picture shows the oversized mounting flange I made and welded to the mandrel shaft to better support the lower wheel.
With the wheels mounted:
Unfortunately (or not, who knows) at this time in the build process I suffered ‘burn out’ – I just needed a break from the project, as I had been working on it (and thinking about it) constantly. I decided to put the project on hold for a time, to regain motivation to push to the finish.
Little did I know how long it would be before that motivation returned.
A Year And A Half Later…
Fast forward seventeen months. The saw has been standing in my shop, untouched and collecting dust all this time. By now, I have this website and I’ve finished many other projects, some of which are featured here, and I feel the urge to finally complete the saw.
First step is to reacquaint myself with it – the pertinent details are foggy: how long will the blade be? How fast is the saw? So I take the time to make a ‘blade’ from edge banding material with a total length of 120 inches. I try this on the saw and shot a short video of the action:
This confirms the blade length and I order one from R&D Bandsaws – 3/4″ wide, 3 tpi Swedish silicon. Having the blade in hand is the motivation I need to press on.
When it arrives, I can’t help but try it out:
Cutting into 6″ of very hard maple. I’m just a little apprehensive, not enthusiastic about my chances of escaping unscathed if the blade snaps or pops off, therefore, I take it easy. Even with no blade guides or tires at this time, it seems to cut well.
However, these two tests uncover some issues: the upper wheel seems to have a noisy bearing, the 8″ pulley on the drive mandrel has come loose and I’m not liking the bearings for the mandrel – these are (cheap) oiled sleeve bearings and I’d prefer sealed ball bearings.
The first problem I tackle is the drive mandrel. I remove it from the motor assembly subframe and inspect it, finding that the set screw on the 8″ pulley had worked itself loose. I cleaned everything up and used PL Premium as thread locker on all of the set screws and even between mandrel flange, the pulley and the stop collar. I don’t want this coming loose again!
address the mandrel bearings. I buy four new sealed bearings and make two pillow blocks to hold them. First step is to drill out holes, slightly undersized:
These holes are close and it doesn’t take much time at my sanding station to make them exactly the right fit:
Each pillow block holds 2 sealed bearings, and this should be enough support for the mandrel shaft:
Then reinstalled on the motor assembly subframe.
As it turns out, the tension on the blade will force the motor assembly outward, causing the lower wheel to go out of vertical alignment. This is caused by slop in the drawer slides that I used to make the motor assembly move up and down. To counteract this, I added shims to the rear pillow block and later changed it to make it adjustable. This is one of the better reasons to not do things this way. Live and learn.
With the shaft / bearing problem out of the way, I move onto the part of the project that I stalled out on months ago – the tensioner.
The tensioner has two purposes: the first is to put working tension on the blade. The second is to allow for blade changes. In my case, I had to make it so it would push down against the motor assembly subframe for blade tension and also be able to lift it up, to facilitate changing the blade. To do this I used a 3/8″ lead screw and the gearbox from a scrapped mini grinder. This has about a 2:1 gear ratio (the output is slower than the input) which was perfect for this.
There are no springs, just the downward force applied from the 3/8″ threaded rod between the grinder gearbox and the motor subframe. This works flawlessly and was simple and fairly easy to do, once I had the details worked out.
There is an adjustable limiter for tension and for raising the wheel for blade changes. This is the purpose of the 2 pairs of double nuts above and below the subframe crosspiece (blue arrows):
I determined the best blade tension then I set the lower double nut set to stop the tensioner at that point. Likewise, I cranked the wheel up to where I can remove the blade and fixed the upper nuts in that position. This is helpful, since there isn’t much space between the top of the lower wheel and the underside of the table.
I then added support on the frame and a hand wheel to turn it easily.
The action is very smooth and there is no need for any locking mechanism – the setting remains unchanged and will not vibrate loose.
In the end, my trepidation over this part of the build was unfounded.
Sometimes we can turn an easily solved challenge into insurmountable problem, usually by over thinking it. Best to dive in, clearly define what needs to be done and figure out the best way to do it.
I made the lower blade guide first, since it is fixed to the frame and therefore easier to construct. I wanted to use this to test an idea I had: to use UHMW plastic for the guide blocks. Ultra High Molecular Weight plastic is a low friction material, used (in woodworking) for jigs and other shop built fixtures that have surfaces that need to slide smoothly. For example: the guide bar on a mitre gauge or cross cut sled that rids in the slot in a table saw. I used pieces of this for the guide blocks:
These are 3/8″ x 3/4″ and about 3/4″ long. They show no signs of wear after my testing. Admittedly, my test period was brief, but also was more stressful to these blocks than the normal operation of the saw would be. I’m confident, given the early results, that these will work very well for this purpose.
With the lower guide done, I turned my attention to the upper. Initially, I was going to make this one fixed as well – this band saw is meant to be for re-saw uses only, therefore I thought that a moveable upper blade guide was unjustified. Giving it some more though, I went back on this decision and began to construct the parts for the guide.
Starting with a pair of solid maple mounts, these are 1-1/4″ thick and have precise 1-1/4″ holes cut in them to receive a 1-1/4″ diameter guide post of the upper blade guide assembly:
Complete and ready to bolt in place, 4-1/2″ x 1/4″ carriage bolts fix them to the saws frame. The lower mount has a knob to tighten, to lock the guide post in place.
Carefully laying out and drilling the holes through the frame, I use a step drill to enlarge the pilot holes:
The mounts installed and the guide post in for a test fit.
The first piece of the upper blade guide is welded in place, this is made from 1/8″ thick mild steel that is fully welded to the end of the guide post and notched around the blade. Like the lower one, the upper will use the UHMW blocks, clamped in the same manner:
After adding the other steel parts, holes are drilled and tapped for the guide block clamping screws. These are #10 x 24 machine screws and they will pinch the jaws of the holder closed around the plastic blocks.
The thrust bearing is adjustable in and out and locks in place using a jam nut:
I removed the lower guide to paint, along with the upper and the guide post mounting blocks. Paint really cleans up the appearance of the welded parts.
Here’s the whole assembly, finished and in place:
Dust Chute And Back Fairing
Having studied a few commercial models, I came up with a design for the dust chute. Much of the work from this point forward is a build-up, one piece cut to fit on the previously installed piece. The dust chute illustrates this well.
The first piece of wood is cut to fit inside the space between the frame members, and is screwed in place from behind:
The next is cut to fit on top of the first one, and screws into it. It is bevelled to create a slope toward the front, as well as toward the side.
The next part is notched for the blade and screwed in, and it’s easier to see the forward slope on this one. This part is removable for blade changes:
And finally, the last parts are screwed in place. This should channel most of the dust out. Of course, it isn’t complete – the front cover makes up part of it and there is also a rubber washer that needs to be installed around the blade slot, but more detail on that later.
Turning attention to the rear of the machine again, here’s some detail on the tensioner crankshaft:
The ‘bearing’ for the shaft is the piece of aluminum tubing, cut just slightly longer than the thickness of the block that it goes through. This lets it turn freely when the nuts are tightened:
A plastic crank from a broken table saw is added. It’s appropriately labelled “up – down” and turning it in the “up” direction increases blade tension.
The back fairing is built and put on. Made mostly from 1/4″ plywood, it is removable to access the motor assembly:
The purpose of this fairing it to keep dust off of the motor assembly and for appearance – it cleans up the look of the saw back there. Functionally, it also provides support for the table.
The table on this band saw is fixed, it doesn’t tilt. Seeing as how this saw will mostly be used for resawing stock, it made little sense to complicate the build by making the table tip. In the unlikely event that I’d want to cut something on an angle with this saw, I can make a ramp at the correct angle.
What I do consider very important for this saw is that the table be strong and not move or deflect when I put a heavy piece of wood on there for cutting. Getting the table properly reinforced is a lot easier when it is fixed in place.
Starting with a piece of 1/2″ Baltic birch plywood that is 30″ x 24″, I notched it to fit around the main support post and around the blade:
I used 1/2″ to maximize the resaw capacity (every little bit helps) and I happened to have this size piece already. After giving it some thought, I decided the best way to have access to the blade and lower blade guide was to make this whole corner of the table removable. I would make it so it would slide in and out, held in place with two bolts with knobs.
The main part of the table is bolted to the frame and has one screw at the back, into the motor assembly cover.
With the main table in place, I start to construct the side support. Made from solid maple, it is glued and screwed to the wood cleat that’s on the edge of the lower frame. It is meant to be as rigid as possible, to support this side of the table:
Before I went any further, I checked to make sure that the blade is 90 degrees to the table, in both directions:
It’s easy enough to make an adjustment now, before the glue has set. Fortunately, the blade is oriented correctly to the table and I don’t need to make any changes.
Adding more parts to the main table requires a few clamps. A solid wood edge for the front, plus a piece on the bottom to form the slot for the removable section of the table:
The removable section cut to size and put in place. I cut the blade slot with the band saw blade. This creates a zero clearance slot for the blade, which should hold up very well.
Solid wood edging is glued on, and taking the plastic pads off the spring clamps lets me position the clamping force with more accuracy:
To hold the corner in place, a carriage bolt is used at the back.
And another at the front helps to keep the top in line. Both are countersunk, below the surface of the table:
Sliding the section out for removal. In the picture, you can see the tongue that fits in the slot along the side. This gives complete support for this part of the top.
The front cover is simple yet complicated. It needs to be strong and lightweight and it must fit around obstacles. Therefore, I thought the best way to build it would be in place, one piece at a time.
Beginning with a piece of fir 2″ x 3″, I mounted three regular butt hinges mortised deep enough in the wood to surface mount the other leaf of the hinge onto the frame:
I used self drilling sheet metal screws to attach the other leaf to the steel post.
I then started adding parts, fitting them as I went. The advantage is that you can easily see if something is not in the right place or hits another part of the saw:
A small but important part, the blade cover that mounts on the main support post.
Some plywood to thicken the cover in the right place. Since the outer skin of the cover will be 1/4″ plywood, it’s a good idea to add stiffeners where needed:
Getting creative with the clamping. Here I’m gluing on the guide strips for the sliding blade guard. Using spring clamps is handy but their reach is limited. I get some help from strips of wood and a wrench.
The bottom half is complicated by the dust chute:
It needs to be made to fit around it and when closed, seal the cute from the lower compartment.
With the 1/4″ plywood skin attached. I used glue, nails and clamps to fix the skin in place. It was cut out slightly oversize in one piece, from a full sheet. This helps to add some strength to the cover by eliminating joints:
One final piece is put in. This lines up with the guard on the post to close the gap when the cover is shut.
Finally, I trim the edges flush with a laminate bit:
It’s ready for sanding and painting.
Efficient dust collection is important to me and I like it to be simple. For a band saw, there will be very little airborne dust – most will be pulled down with the blade. The dust chute was designed to catch as much dust as possible and in doing so, it would need a place to put it.
I came up with a solution that works well. It’s a long box, open on the top and made from 1/4″ plywood. One of its neat features is that it also holds the bottom half of the front cover closed by hooking over the leg and slipping into position over the front cover:
Here’s a top-down view, showing the way it’s made. The sides extend and these are what holds the front cover closed. The box is simply constructed using glue and nails. A shallow dado was cut for the inside panel to ensure good alignment.
Here’s how it hooks over the leg:
Once in place, a wooden clip holds it closed. The clip is screwed down further in to allow it to spring up to release the box for emptying. The whole thing is pretty tightly closed when in place and just sits there, filling with dust.
I made guards for the switch cover and glued them in place:
These are just pieces of 1/4″ plywood cut to size, sanded and glued on to prevent the saw from being accidentally turned on. A small thing to do but taking the time to do the things that increase the safety margin are well worth the time and effort.
Getting the wiring sorted. I’m using an old 3 conductor extension cord for the wiring, keeping it neat and safe. Wire nuts (marettes) don’t work the greatest on stranded wire, so I wrapped them in electric tape to make sure they don’t vibrate loose:
A metal cover to close. It takes some time to get it all done but rushing through this part is not worth the risk.
The cord exits the saw at the bottom. I tied a knot in the cord to prevent it from being pulled out. The power cord is about 12′ long which is good for plugging it in directly, and avoiding extension cords:
The on/off switch in place. I painted the box and the cover black to match the rest of the saw. I used an ordinary light switch and this switch may fail in time, (the inrush current for starting the motor exceeds its rating) but these are cheap and easy to replace.
Having used the saw a few times, I can say that this is probably the ideal location for the power switch. Easy to reach from the cutting position.
Some parts you can buy, some you have to fabricate. Others, like the catch that holds the front cover closed on the top, can be bought but may work better if you can make it yourself.
I decided to make this part myself, starting with a piece of heavy gauge sheet metal:
The first cuts define the handle and it is then bent using a bending jig. Pliers or a vise also work.
The rest of the shape is cut out and the pivot hole is drilled:
Refine the part by grinding off the sharp edges.
And the finished product is painted and installed. The look I want, the perfect size I need and the exact function:
Casters are added to the leg. These let me move the saw by tipping it back onto the wheels. I can then roll it where I need it. When the saw is upright again, the wheels are off the floor.
A rubber gasket is fashioned and put in the dust chute:
This reduces the amount of dust that gets through to the bottom. After plenty of use, it has proven itself and shows no sign of wear.
A look at the back of the finished saw:
The blade tension adjustment crank.
The blade tracking hand wheel:
And the finished saw.
A big project, it took many hours to complete. At one point, after seeing it sitting in my shop for more than a year untouched, I felt I would never get it done.
Glad I was wrong.