this video is a little bit longer, but alsovery detailed. i first talk a little bit about the saw itselfand explain why i wanted to make new wheels for it.if you only want to see how i make the wheels, just click the annotation in the video. this is my homemade bandsaw, that i built about one year ago with the plans from matthiaswandel (link in the description) and as you just could see it performs reallywell. but when i built it i changed several thingsin the design, so it would fit my needs. the first change i made was the size of thecart, that goes under the bandsaw. it is a
little bit wider in this direction, becausei originally used this very heavy motor and it had to be supported with a bigger cartso the saw won't tip over because of the weight of the motor.but a while ago i upgraded the saw with this motor, which i got for free. it's also a 2hpmotor and it runs at 1400rpm. so now with this motor i got the blade speed that i likeand that's about 21 m/s. the only challenge with this motor was mounting it, because itdidn't had a foot, but just this mounting flange.so i made a new belt cover and this piece is now really thick and the motor is boltedinto it. but because the motor has such a high starting torque, it always wants to rotatethis way when i fire it up. and to prevent
that i jammed a block in here, so the motorwill stay in place. and the belt always slips a little bit when i turn it on.with this motor i now have a blade speed of about 21 m/s, which is really fast. but nowthat i worked a little bit with it i really like that blade speed and the motor is powerfulenough for that blade speed to work properly. but the high blade speed also brought someproblems with it. so because the wheels now spin much faster, i got a lot more vibrationon the saw and i had to lighten the wheels so i cut big holes into it and also re-balancedthem better. and now they can handle this high rpm and the saw doesn't start to vibrate.the other problem was, that a higher rpm also meant more centrifugal force. and this the14" inner tube that i originally used on this
saw. but it couldn't hold up with the highrpm. the centrifugal force pushed it outwards and it slipped off the wheel, so i had toput on 12" inner tubes on this 16" wheel. but the major problem is the sawdust, thatflies around here and because of centrifugal force gets caught in the wheel and that'skind of a problem with this wheel design. you can see that here is a little layer ofdust at the side of the wheel, which is not actually a problem. but at some point i gotthe sawdust under the tracking part of the wheel and this made it uneven and really roughto the blade. actually when i cut up the walnut bowl blanks there was so much dust betweenthe wheel and the tire, that it started to come of while saw was running and there wasa blade on here and this was kind of scary.
so i thought a little bit about it and finallydecided to make new wheels with a slightly different design then the original ones. andthat's not to bad, because i wanted to change the bearings anyways someday and now thatseems for a good opportunity, because they sometimes start to make a really annoyingrattling noise. {rattling}so let's make them! so here are some of the bearings i used forthis saw. i used them because i got them for free and three of them were in good shapeand one of them was in reasonably good shape, but this one is what i think makes the rattlingnoise. so i ordered some new bearings to replace the old ones.i wanted to make the wheel-body out of mdf
this time, because it is really flat and consistentand should be easy to balance, which was my main concern on this build.i bought 16mm mdf and in order to get the right thickness i have to glue two piecestogether. so i took a little bit of glue and spreadit over the entire surface. the band-clamp is there to just keep the two pieces alignedwhen i clamp them, so nothing can slide around. then clamping with 4 spring-clamps ...and some more spring-clamps ...and a lot of other clamps. i also tried to get some clampingpressure in the middle of the sandwich with
two blocks and two rails that are clampedtogether. while i'm waiting for the glue to dry, i can start on making the new bearingflanges. they have to be really strong and need to be made out of birch-plywood. i hada scrap piece and luckily it had the same thickness as the bearings. i simply cut 4squares out of it. then i marked the middle of all of them. next i need to cut a holein the middle to press fit the bearing into the flange. the bearing has an outer diameterof 52mm and i have a forstner-bit that cut a 50mm hole. that's too small. i have a goodhole-saw that cut 51mm holes. it would work, but the fit is then so incredibly tight andit would be really hard to get the bearing
in. but i also have a cheap hole-saw, thatsays it cut 51mm holes, but it cut a little bit bigger and that's good for press fittingthis bearing. so sometimes the cheaper tools are the better ones. to prevent tear-out, i drilled from both sides. next i hammered the bearing in just a littlebit with the help of a piece that has a hole in it to prevent the bearing from damage ofthe hammering. the rest of the work is done at the vice. after that i trimmed all of themto their final size. and rounded and sanded the corners.
now the glue of the wheel blanksis dry and as i don't have a compass big enough i used a scrap piece with two holes in itinstead. then i marked the layout for the holes that i need to cut into them. i drilleda little hole in the center and used two of my small storage boxes, which guide the drill-bit.this hole is then used as the pivoting point to cut out the circle shape. it was at thiswhen i noticed that it would have been better to first cut out circles and then glue themtogether, but it didn't matter really much. i had to drill the hole in the middle by handbecause my drill-press can't reach there.
but it doesn't need to be super accurate,just big enough for the shaft to fit through. the big holes i then cut with a hole-saw onthe drill-press. i made more and bigger holes than the plans call for to lighten the wheels.this took a lot of time, because the mdf really gums the hole-saw and i had to clean the teethseveral times. but it worked ok, i didn't get too much burn marks. but the holes cutwith the forstner-bit went really easy and also produced a lot of chips. then i sanded over all the burn marks left by the hole-saw. now i'm ready to glue on the first flangeon both wheels. it should be as centered as
possible and in order to do that i made thislittle helper. i just turned it on the lathe. it fits in the center hole of the wheel andthe flange fits on top. and now it's centered. i spread the glue just on the outside, sowhen i clamp the flange, the glue won't squeeze into the bearing. while the glue drys, i canstart to take apart the saw to get access to the wheel shafts. i case you wonder aboutthe wood pulley on the motor. it is still in really good shape. here are the old wheelsand the shafts and as you can see the bearings
were quite rough on these shafts. so let'ssee if the new bearings still on this shaft. "yes" i still wanted to get rid of some burrand rust, so i chucked them in the lathe and 'ground' it away. and some sanding with 600grit paper. now with the glue dry on the first flange i can carefully slide it onto the shaft.and now i can put on the second flange. and it has to be glued on exactly straight, sothere isn't any kind of side wobble in the wheel. the flange is now just clamped on andi can check the wobble with this piece by looking at the gap. and right now there definitelyis some wobble. i tried to correct the wobble
by changing the position of the flange withsome small taps. i look for the part of the wheel that's closest to my reference pieceand tap at the opposite side on the flange. now the wobble looks something like this...muchbetter. then the same procedure with glue. but this time i only had about 30 secondsto get it right until the glue started to set. well now the glue set and i can't changeanything. i'm not super happy, but it's very close. yeah the second wheel came out better. i already could hear how much quieter the new bearings are. {silence} i put on the temporarypulley just with clamps so that way it was
easier to adjust it so it runs true and ialso don't have ugly screw holes in the wheel. so here i set up for turning the wheel. andnow comes the part where i want to change the design. so i don't want to turn just acrown onto the wheel, but a full channel with a crown in it. turning this mdf really makesa lot of awful dust, so i setup two dust collection hoses and also wore a dust-mask. i first turned it round and then created the channel. so now let's check the size of thewheel. the plans call for 40cm diameter wheels or a circumference of 125,6cm and as you cansee i made it a little bit smaller, but i did this on purpose, because the varnish iwill out on there and the tire then will also
have a little bit of thickness and with thesethe wheel will then have the right diameter. i also looked that the crown is exactly atthe glue line, because the glue line is really really hard and it should hold up the tensionof the blades better then just the mdf. and hopefully with this design the sawdust that'son the side of the wheel just can't get under the tire and flies away. then doing the samething again with the other wheel. now before i can go on with putting on the inner tubeand balancing the wheels i have to varnish them, because this mdf really needs to beprotected from moisture. the varnish is a high quality solvent- or oil-based pu. i got it from a painting store and it was a lot more expensive the stuff from the hardware store i used before. but when i look at the result...
i never want to use something elseagain. so here are the wheels now with two coats.... and i have to say they look amazing. next i have to put on these inner tubes as the wheel tires. but just look at that. that'sthe old lower wheel and this is the amount of sawdust that was in between the wheel andthe tire. and that's the sawdust from just two weeks, because i had to clean the wheelafter i resawed the slabs for my wooden bucket. i needed to cut them thinner. but this wasreally easy, because i could follow some ridges. now i simply have to get this 12" tire around the 16" wheel.
i thought you now can see me failing several times. but because i cut theinner tubes thinner, they stretched a lot better and was pretty simple to get them on. next i need to attach the drive pulley, centered on the wheel. so i first clamped it, looked how true it run, made adjustments and screwed it on. 4 drywall screws will drive this bandsaw.now with everything attached i next need to balance the wheels. the plans call for usingsome really easily running ball bearings and
putting them on a screw driver and then puttingthe wheel onto the bearings. but unfortunately my small bearings don't fit inside the bigbearings. now my solutions to this is. i made some housings for these small bearings andthis pin fits into the big bearing and then i can put a shaft through it and balance thewheels on it. i used threaded rod as a shaft. i just let the wheel spin and settle at theheavy point. and now i know that i have to remove some material from here. then repeating this process until it's perfectly balanced. one thing for sure: it's much easier to balancea mdf wheel than a plywood wheel. you see how much material i had to remove here toget it balanced and here just 4 holes.
spray lacquer seals the exposed mdf again. theni could install the wheels back on the saw and make a really important test to see ifthe tire stays on the wheel. looks good. i made wooden washers, which help to securethe wheels on the shaft. then assemble more, install a blade and fire it up. so check thisout. it runs really quiet. seeing that it works i could put on the rest. the saw is complete again, so now let's check the vibration
with the "balance a coin test". i would callthis " good enough" while i was working on the saw anyways i took that opportunity andinstalled a wheel brush for the lower wheel and it will just keep the tire clean fromsawdust. and without one there will develop a thin layer of fine dust over time and matthiaswandel himself mentioned this as a feature, but i don't think that's a 100% right. thisthin sawdust layer will protect the tire a little bit when you only cut up plywood ordry wood. but when you cut up green wood. some small logs or bowl blanks, then the sawdustwill really stick to the tire and gums up the inside of the blade and that's not reallygood for the blade. so i don't know how well
it will work. but it definitely can't hurt. and now making some test cuts. and as you can see the dust just can't get under the tire anymore. that's exactly what i wanted to reach. and i think the cut result speaksfor itself.
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