mklotz70 belt sander build

[mklotz70]

Yep :)

That's how I was planning on making the sewing machine motor work before I got this. I want to keep the belt speed up over 3000sfpm. The Burr King runs at 7200sfpm....not sure I can get that kind of speed....not sure I need it. Having variable will actually let me figure out what range of speeds work best....so I'll know if I use a fixed speed motor with stepped pulleys on another one :)

 

I'm tempted to use the flat belt that the tread mill used...I think it will drag a lot less than a V belt, just not sure if it will slip more.

[mklotz70]

Got some more progress made. Never as much as I want or expect, but still...it's progress :)

 

 

My buddy A100addict was over. While I was showing how the motor will spin up to full speed...in reverse.....the flywheel came off!!! Luckily, it nestled itself into the frame piece.....cause it was spinning at around 7000rpm!! It took nearly 10 sec to come to a stop! I was backing up into Dave and he didn't have anywhere to go.......it was rather comical.......after it came to a stop! :)

 

 

 

 

 

We played around with some with an idea to put the motor up on top...so it could be a bench model like the other versions. Looks like it can be done and then mounted to a HF grinder stand.

 

 

 

 

 

 

 

Got the flywheel cut off.

 

 

 

 

 

 

Got the bearings into one of the pulleys. One of the idlers like this will keep it's crown, the other one got flattened since it will be a platen roller......meaning I'll be grinding directly against it so I don't want any curve. The shaft I got was larger than 5/8".....what a royal pain!! Had to tweak the tailstock to get it to cut the same diameter from end to end. I cut half of the drive shaft...then when I turned it around...I had to tweak the tailstock again...no clue why, but what a pain!! I do believe I'll simply by 5/8" shaft next time!!!

 

 

 

 

 

 

 

 

 

I thought I was going to be able to use one of the pulleys as the hub for the secondary drive pulley....didn't work out. So...as I should have done to start with, I made one from scratch. I made it press fit and actually knurled the mounting surface to give it even more grip. It spins pretty darn true. More pics of how it was made are in the machine work thread :)

 

 

 

[BJW's FiveTen's]

As always, what nice work. I like all the info you include in your posts. I really like this belt sander. Keep up the good work. I only hope to be able to fabricate as well as you do, someday :D Thanks for inspiring some of us to keep building.

[datsunwizard]

Mike,

I have used lots of those treadmill motors over the years. Just a heads up, I see the you cut down that flywheel which is fine, but in doing so you removed the fan portion of the flywheel. You need to put some type of fan to cool the motor, if you are going to run it for any length of time.

 

Monte

[mklotz70]

BJW...Thanks :)

 

 

Wiz....I figured that since I need to put the electronics in a box, I'll capture the entire motor as well. I don't want all the grinding dust in the motor. I'm thinking the box will have it's air vents at the bottow with some sort of filter, then at the top on the sides, I'll have a compter fan or two pulling the air out of the box. I'm going to leave the thermal cutoff switch on the motor too...just in case. I may leave the sides open on the box....we'll see. I think it will depend on just how much grief it is to build it :)

 

How do you like the torque on the motors? What have you powered with them?

[mklotz70]

Made some decent progress....not quite as far as I wanted to get, but the lathe work always takes about 4x's longer than I imagine.

 

First up was the 8" caster wheel. It's cast iron/steel and it's heavy. It was machined for the bearings and the wheel surface, by the manufacture, so that it wouldn't be obnoxiously out of whack, but for the speeds I want to run it at....it needed to be a lot more true. The challenge with boring out the bearing holes was being able to grab the wheel with the lathe chuck accurately. I have several different sizes of centers (coned piece of bar about 3" long) that I can chuck up in the lathe. I picked an aluminum one....trued it up with a quick cut. The AL one was already the right size and the AL will "grab" the wheel better. I squeezed the wheel between that and the bull nose center. It seemed to spin fairly true. Normally you would use a lathe dog to drive the wheel, but I take light cuts and the AL center seems to grab well enough. I cut a 1/2" lip on the inside of the outside diameter. I could then grab that "true" surface and do the rest of the cutting. Since that first cut was concentric to the bearings...fairly true, but not great......I was able to bore the bearing holes and cut the urethane surface while I had it chucked.

 

I was able to extend the boring bar enough to cut the bearing mount on both sides. I left a lip at the same depth that the bearing is wide....so that when I pressed the bearing in, it would stop on it's own. I actually had to press both of them in!! :) I got lucky!!! The other reason for the lip is so that if they loosen up a bit, the lip will stop the wheel from simply running right off the bearing. Basically, the wheel is stuck between the bearings. Yes, one bearing snout is shorter than the other because I screwed up the bore size....I just cut it down a bit and made the bearing mount a bit closer to the center.....oh well. :)

 

 

 

 

 

 

 

 

 

 

I needed to get rid of a bit of the weight. Everything was going just fine, 'til I got to the point where I thought the hole saw should have gone through. Turns out the casting isn't lined up from one side to the other. Oh well again!! I want my tool to work....I'm not one of those guys that gets completely hung up on having to make it perfect. A couple more will be built, so I figure this is the prototype...I expect it to have mistakes :)

 

The vise was actually level enough to register the heavy side. I'll build a leveler later if this isn't close enough. As you can see from the drill holes and die grinder marks...the one side was way heavier. I can hold it by the axle in one hand and spin the wheel fast and not feel any out of balance. Close enough for now. I'll probably end up making one out of AL later.

 

 

 

 

 

 

 

 

Sooooo much easier to do the bearing mount areas when the outside of the pulley is flat!!!! Didn't take near as long to do the platen pulley. I'm also getting a lot more comfortable with setting up the dial indicator and truing up the part!! :)

 

 

 

 

 

The choice for the drive pulley came down to spending a lot of time cobbling a 2" AL one together....or making a 3" steel one.....I went with the steel. I'm gonna be sooooo sore for the next couple of days. Standing at the lathe for hours like that is brutal!!! I wire wheeled the rust off before it went in the lathe. The rust dust is disgusting to breathe....and rust is extremely hard.....dulls the tools up quick.

 

I first cut a 1/2" pocket in one side. Partly to eliminate some weight, mainly to be able to grab the pulley from the inside. Both sides have the same 1/2" pocket. I marked the center of the pulley and cut a 3 degree taper on each half. I probably could have done half that, but I read 3deg on Beaumont's site....so that's what I did. I was going to bore the hole....but ended up drilling it....came out nice...haven't spun it yet, but it should be fairly true. I'll put it in the mill and put a set screw or two in it :)

 

 

 

 

 

 

 

 

 

 

 

Time to throw one of the belts on and get a rough idea of how it looks. It's getting there. I'll move the drive pulley back as far as I can to get as much "wrap" as I can. Since I have 21 of these 1.5" belts, I'm torn with whether to leave the pulleys at 2" for when I start running those.....or just make two sets of pulleys.....which means I'll need to modify the two platen pulleys on here.

 

 

 

[datsunwizard]

 

How do you like the torque on the motors? What have you powered with them?

 

The torque falls way off at low speeds. The early thread mill motors made by GE had a feedback signal that went back to the motor control board, so when the motor was slowed down by increased load, the control would increase the voltage to the motor to keep the motor at the original set speed. The photo optic sensor at the back of your motor is used, I think, to display the amount of miles you have run or walked on the thread mill. Maybe you can use that signal for displaying the surface speed per minute of the belt on your MKIII model!

The last item the I made with a thread mill motor is a diamond lap grinder for sharpening a carbide scraper.

 

Monte

[mklotz70]

Actually..the photo optic is used to maintain speed control on this unit. In one of the vids I posted, I was showing how if I tried to slow it down, it would work harder to maintain speed....then when I let off, it over sped and even coasted until it came back down to speed. That's why I took the flywheel off. It will get a more instantaneous speed change with it out of the picture. If it doesn't work, it was only $25. I think there's a tach output on the board. That may be an upgrade for way down the road.....I just need to get this done and out of the way right now. :)

[mklotz70]

Even before I finished the drive pulley, I did some figuring on the belt speed with this pulley......a lot slower than I was hoping. Mainly because the multi-groove pulley setup from the treadmill is a 3-1 step down. I could either remake one of them.....or make a different drive pulley. I figured I'd finish up this pulley anyway...may use it on a later one :)

 

I opened up the top of the hole so that I didn't have to thread the entire depth. Basically, the bottom 1/2" of the hole has threads, the rest was clearanced so that the set screw would drop in to them.

 

 

 

 

 

 

 

 

 

gcmustang dropped off some nice chunks of aluminum(Thank you, thank you, thank you!!!!!).......so new drive pulley it is!! :) AL is soooo much nicer to work with!!

 

 

 

 

I ended up having to drill/tap a hole in the side to put a bolt in to act as a lathe dog. The centers weren't grabbing well enough this time. I started off by grabbing it by the outside diameter, but it was not very concetric. Since I'm only using a 5/8 shaft, the existing hole was off center that I would have to open it up farther to get it true. So, I trued up the OD first. Now the center hole is close enough that I can open it up to 5/8". I know the surface finish isn't the best...I don't care.....at this point, I'm about finishing this project quickly!!! :) Now that I have a 1/2" pocket made in one side, I can grab it from the inside to turn the rest...just like with the 8" wheel.

 

 

 

[hessianben]

man, even though I don't know half of what goes into making all of these parts...

I LOVE watching it take shape!!! tools are cool...:D

[mklotz70]

Thanks. Glad you like it....thanks for saying so :)

 

I've always loved the builds I've found on some of the machine shop sites....figured someone else might like the blow-by-blow type build as well :)

 

 

 

The new, nealy 6" pulley should put the belt speed back up to around 3750sfpm with the motor at 7000rpm. That's pretty much right where I wanted it. If I want to go faster...I'll make a new multi-groove pulley for the motor drive. An added advantage to this new drive pulley......I'll have a lot more surface contact with the sanding belt, so hopefully, it won't slip.

Edited December 11, 2009 by mklotz70

[datsunwizard]

I am glad that your motor has the feedback, it should help a lot. On my diamond lap grinder, at low speeds the motor does hunt at varying loads. It is probably a good thing that you are going to be running at the higher speeds. I think that the rating of 2+ hp is at the higher speed ~7000 rpm.

 

Monte

[mklotz70]

I'm guessing you're right about the hp at higher rpm's. I'm hoping to "know" how it works in a few days :)

[zenndog]

Hey, I love to see your machine work but don't you have like 20 Datsuns should be working on?

[mklotz70]

Thanks.....and it's only 5...the second NL320 isn't on my list of vehicles. :) In fact, I'll be making more chips in about 20 min :)

[mklotz70]

I flipped the 6" pulley around in the lathe and did the 95% of the work from that hold. I did turn it back to this side and clean it up some more. The texture on the outer face is from sanding. I wanted it to have a bit of traction. The fun challenge is going to be trying to do the set screw :) ....maybe a key way too.

 

 

 

 

[zenndog]

For the set screw, can't you just drill through the outside surface all the way to the raised area in the center. That shouldn't hurt the operation because I am guessing that is just a drive pully? Might be hard to tap and may look sloppy I guess.

 

For a key way use a drill press or a mill as a rigged broach. Use a cutting tool from your lathe to make the broach bit, mount it in the chuck of your mill, then drive the chuck down with the motor off and the spindle brake locked. Make a .005 cut each pull. Maybe it will work. Plenty of tapping or cutting fluid.

 

5, 20, 6....... is there really a difference?

[mklotz70]

That's about what I have planned....no spindle lock on either :(

 

 

I don't understand the last line :(

[Figbuck]

Mike, nice fab work. I like the belt tracking adjuster. Having built buildings out of the ground, I realize that it's all about good design and layout.

 

In the process of doing take offs of drawings for estimates/bids, I would see a line or two and think what does it do functionally? If I could loose one or two of those lines, it would be so much easier, faster = cheaper. When I ask the architect or designer what the lines were for, the answer was, it just looked good. Can I leave them out and save a hundred man hours and thousands of bucks? "Sure, I'm not married to the appearance." Sometimes designers are and someone simply has to pay for the result. The ability to envision in three dimensions is not easily learned. I have seen things drawn that can't be built, or things that once they are constructed can't be adjusted or serviced.

 

I have watched the evolution of race cars and motorcycles for years. From the years when a top Indy car team came with a car, spare engine, towed in an open fifth wheel trailer to a gravel paddock... to teams with tractor trailers that fold out into portable garage with two cars, six engines, full machine shops on board, set up in state of the art permanent garages. The evolution of technology from hand drawing. to CAD/CAM, from seat of the pants driver intuition, to onboard real time engine management and suspension data acquisition, has been amazing

 

One of the big advantages of CAD/CAM is the ability to package components tightly for aerodynamic advantage, loose mass=weight, move/adjust centers of gravity. It also allows you to visualize how parts can be manufactured, assembled, adjusted and serviced. Sophisticated race car design and construction is made possible by sophisticated tooling and machine work.

 

It is fun to build stuff and do a workman like job. I think about how satisfying it is to look at a Lamborghini Murcielago or a Ducati DesmosediciRR. Utilitarian objects that are crafted as works of art. Nice work if you can get it! On your Machine Work thread, Datrod related a story where an artist friend remarked that his work was truly art. In my mind, the art is in the conception, not so much the execution. Doing the work is merely craftsmanship. Being fast, efficient and flawless in production only transcends craft into art when the underlying utilitarian conception is successful and then attention to detail makes the parts and machine appear graceful. If it looks fast, it probably is fast.

 

Props to you for not being afraid to realize a concept, regardless of time cost. To spend cash efficiently and judge the trade offs; Is the resulting capability worth the money or is my time better spent getting the capability I really want or need.

 

I think about building tools all the time. Sometimes I can afford to stop and build a jig or tool to help out me in the long run. Sometimes I spend the cash for something off the shelf. I have needs for woodworking machines that I can't afford or don't exist. I dream about having the time and or the tooling to fab machines all day. Guys like Datrod, you and me would be dangerous with real money! Not because we are half-assed decent craftsman but because we can visualize.

 

When I look at your projects, I appreciate the time you have spent. Time to acquire the experience based knowledge to strike out on a project knowing that you have a desired specification, and that you will be able to flesh out the details, improvise with found objects/materials to solve problems you encounter. Time spent working to make money to buy equipment, study methods, materials and learn by trial and error. Only time spent doing this kind of stuff gives you the vision to build in your head and maybe realize the pitfalls and end results.

 

One of the reasons the is a dislike of of most architects and designers by tradesman is that they have never really built anything. The most successful ones have that passion to get their hands dirty and spend time to actually build things. You said one time that it is about the process. The medium happens to be Datsuns for now but it could be something else... to paraphrase.

 

I get an E-mail news letter from Miller. They have a crazy gallery. Great way to waste some time, but here are some other takes on you sander idea.

 

http://www.millerwelds.com/interests/projects/ideagallery/project/4035226289/

 

http://www.millerwelds.com/interests/projects/ideagallery/project/4035225455/

 

http://www.millerwelds.com/interests/projects/ideagallery/project/4035977086/

 

Like you need some other stuff to waste time looking at, here is a link to a site that I follow. I'm a wood freak so I'm more interested in the capability, but the problem solving and understanding of what the different problems are for desired results is informative. In the way that there was a collaborative effort in solving the problem of a bolt on disc brake for the trucks, these guys are our kind of people. It puts a little different spin on sporting wood. :P If I ever have a lousy dollar and a minute, this is where I'm headed:

 

http://www.diybandmill.com/

 

Oh yeah, I wish I would have seen this thread at the beginning. I have a nice 1.5 hp cap/start motor that I salvaged from a Shop Smith. It has a simple adjustable pulley system for variable speed. If your treadmill thing doesn't fly you can have it.

Edited December 14, 2009 by Figbuck
the usual... I'm a figbuck

[zenndog]

That's about what I have planned....no spindle lock on either :(

 

No spindle brake?

 

 

I don't understand the last line :(

 

5 Datsuns, 20 Datsuns, 6 Datsuns, whats the difference?

 

the last line was just a bad joke:o

[mklotz70]

Zenn.....I get it now :) See....there's a reason for my siggy!! :(

 

 

 

Fig..... It's always very flattering and humbling to get compliments from someone of your caliber. I do remember your first name, from when we met a couple of years ago at Canby. I thought you had met a couple more of us Ratsuners, but if I'm the only one, I'm quite honored!! :) I'm still hoping you'll take me up on lunch someday :)

 

Love the links!!!! I really like the tensioner(2nd link I think). I was a bit tempted to alter my path. I wasn't going to put in any time in the shop today, but after reading your post, I was so motivated and excited, I had to go do at least a little something :)

 

Love the bandsaw link! Let me know if you need any help with fabricating any of the parts for that!! That looks like a really fun project!!

 

 

 

 

I still need to finish the pulley, but I thought with the limited time I had, I'd make more progress on the tensioner.

 

 

 

 

 

 

 

 

 

 

 

I dug around looking for a knob I thought I had.....I just remembered that it went on the shop press awhile back. Oh well...bit more digging, thought I'd see how this turned out. I think it started out as a wheel off another treadmill I parted out a few years ago....back before I knew anything about keeping the motor! I tapped the center to fit the all-thread....once it was in there, I couldn't seem to get it out.....that's a good thing. :) When I put the hole in the arm, I drilled all the way through so that I'd have a locating hole on the other side. Next, I'll open that hole up just a bit, then weld the nut to the tubing. The all-thread/knob will thread through and push on the head of the bolt. That should track the belt rather nicely....I hope!!

 

 

 

 

 

[mklotz70]

I finished the drive pulley today. Doesn't look like much has changed just looking at these pics, but I'll put the other 30-40 up on the machine thread :)

 

 

[mklotz70]

Got a bit more done this morning. I milled the keyway into the axle shaft. It was a tight fit for the key! I put a bit of anti-seize on the shaft and mounted the pulley. I tightened it down and it was a slight bit off when I spun it in the bearing. So, I put the pulley back in the lathe, chucked by the axle. I skimmed the outer edges and surfaces so that it will spin perfectly true to the axle. Now that I've done this once, you can bet that I'll moung the axle a lot earlier!!! I also welded the nut on for the tracking adjuster.

 

 

 

 

 

 

[mklotz70]

I started cutting the axle yesterday...put the threads on it this morning. I put left hand threads on so that with the direction of rotation it won't spin the nut off.......partly too....just to be different :) I used the drill chuck to help center the die holder. I did put a drop or two of oil on first. I actually turned things the right way this time for the left handed thread!! :) Hopefully, tomorrow, I can finish the axle. I got the hole drilled for it....vid is taking awhile...so maybe I'll post it in the morning. :) I need to finish cutting the width down on the 8" wheel before I can finish the axle.

 

 

 

 

[mklotz70]

Took a vid of the final drilling of the axle hole. Using the end mill to drill is something I'd known about, but had forgotten until the other day looking at one of my magazines. I'd kinda been holding off on drilling the hole, trying to figure out how to get it as accurate as possible. There's a lot of things like this that I mentally chew on for awhile. After awhile...how to do it tends to just pop into my head...then I proceed :)

 

Oh....the 4 flute end mill is not center cutting so you can't simply start with one like a drill bit. That's one reason for stepping up the hole size. The other is that the bottom of the end mill has a long cutting edges....if I had tried to use the 3/4" end mill right after the 1/4" starter hole, there was a good chance it would have chattered(vibrated and bounced around) and not given an accurate hole. I'm pretty sure this is fairly hard on the end mill, but it's a common size and fairly cheap.

 

Edited December 20, 2009 by mklotz70