Another mill motor question - garage door opener?

[user 40839]

Greetings, fellow brew boffins.

My shiny new Monster Mill MM3 arrived on Friday, so the project for the next week or two is going to be building a stand for this beauty, and motorizing it.

While cleaning out the garage yesterday, I stumbled across the 30 year old Craftsman 1/3hp chain drive garage door opener that came with the house, which I replaced last year. No idea why I kept it, I think it was basically too big for the trash pickup, and it just sat there waiting for me to do a dump run. On a whim, I pulled it apart, bypassed the switch to see if the motor still ran, and was surprised to find it did.

Pulled out the motor completely, along with the capacitor, and fired it individually. Runs forward and backwards without issue. Hooray!

Now the question is if I can use it, and how?

Without the plastic reducing gears, it's certainly speedy - but anyone have an idea what the RPMs are on your average garage door opener motor? (There's absolutely zero markings on the motor itself, other than it saying that it's a 120v AC motor that was made in 1981). The only way I could guage it was to put a 6" piece of tape on the shaft to eyeball how fast it span, and trying to estimate. I'm THINKING it's slower than the 1725 RPM motors that a lot of folks use, but have no way of knowing...

And in terms of torque, is it safe to assume that a 1/3hp garage door opener would have sufficient muscle to drive the mill?

 

[passedpawn]

It's been done before (or at least proposed). I think it was here, but maybe not. Google.

I know this, because I have a spare opener motor that I was considering for the same thing. Meh, the drill works fine.

 

[weirdboy]

I would say that any motor that can lift a garage door should have no trouble with any grain you can throw at it.

You might go to an auto mechanic and see if they have an RPM meter you can borrow. Or, you can buy them pretty cheap, too...probably more than it's worth for just one little project, though.

 

[lamarguy]

And in terms of torque, is it safe to assume that a 1/3hp garage door opener would have sufficient muscle to drive the mill?

Without the OEM gearbox (or a reduction pulley), the motor won't have enough torque to operate the mill.

 

[SweetSounds]

You could also get a tachometer for an RC airplane (If you really want to know the RPM of the motor anyway)

I'm not sure it really matters though - You're going to have to buy 2 pulleys and a belt anyway right? If that motor sucks, you can just get another motor and hook that one up. Worst case you're out the cost of the small pulley on the motor if the next one has a different shaft diameter...

 

[Homercidal]

Without the OEM gearbox (or a reduction pulley), the motor won't have enough torque to operate the mill.

I'm pretty sure this is true. They are able to open the door mostly because of the gearing.

But it's an interesting project, and I'd like to look into it more myself. It may be possible to find some belts and pulleys pretty cheap to go with that, or sprocket.

I built a crusher out of a windshield wiper motor. It barely worked, but it did work, and my crusher requires more torque than one you buy built. The problem with the wiper motor was that it was not quite 1100% capable, and overheated after a few minutes.

I think the door opener would be stronger and if it doesn't heat up too much, might have enough duty cycle to get it done. If it heats up, the plastic parts inside may fail.

 

[user 40839]

Yeah, I wasn't planning on direct driving the mill with this, I was going to use a belt and sheaves. My main concern for finding out the RPM of the motor is so I can get the correct size sheaves for a final speed in the 175 - 250 range. Obviously, if it's running at 800 RPM, it's going to need a considerably different setup than the standard 1725 RPM motors. (I'd ideally like to stay away from large sheaves, since I want to keep the build as compact as possible, so I'd consider it a big bonus if I could plop an 8" one on the mill, as opposed to having to get a 12, 13, or 14" one!)

 

[weirdboy]

I would think he HAS to know the RPM of the motor...

My feeling is that you have to gear it down no matter what. And, even if it's a little slow it's still faster than cranking by hand.

 

[user 40839]

Well, yeah - there's no way I'm going to try and run my mill at the speed this thing goes.

I think the best bet would be to just order the 12" sheave from Grainger, along with a couple of smaller ones, say a 3" to try on this. If it works, yay, if not then just get the 2" one that will work on a 1725 RPM motor.

 

[maida7]

This may be a silly question but why don't you just use a drill as a motor?

 

[Homercidal]

This may be a silly question but why don't you just use a drill as a motor?

Not silly at all. I actually bought a high amperage, geared-down drill from Harbour Frieght. I wanted a new corded drill anyway. Well, it's not powerful enough to crush my grain. If I had bought a crusher, it would probably work. But my rollers are larger diameter and the extra torque needed to crush the grain makes the drill unusable. It started smoking right away.

So, not wanting to purchase ANOTHER drill, I started looking for alternatives. I ended up getting a nice gearmotor, unused, from work for free. Not all are that lucky. So I'd be interested in finding a method of using low-cost alternatives so that others can build their own motorized crushers.

Even if I didn't have the gearmotor, I'd still prefer to have a mounted crusher, as opposed to having to hang onto that drill the whole time. I crush about 6 lbs in just under 2 minutes. Fairly slow, but much better than using my hands.

Bottom line for me, saving money and "building stuff".

 

[user 40839]

Because I love the idea of just loading up the hopper, flipping the switch, and getting on with other things that need to be done, as opposed to standing there holding a drill. Although logistically, that's not a big deal... it's more that I saw this, and sorta went "mmm, must have..."

 

[Sawdustguy]

Because I love the idea of just loading up the hopper, flipping the switch, and getting on with other things that need to be done, as opposed to standing there holding a drill.

I certainly can't fault you for that because I would do the same thing.:rockin:

 

[Joker]

it's more that I saw this, and sorta went "mmm, must have..."

Looks like the hopper could use steeper sides but other than that its beautiful.

 

[Bubba_Mustafa]

Is a garage door opener motor a continuous duty motor? They really only run for 30 seconds.

Why not just get an AC motor and pulleys or chain/sprocket. You'll know the RPM.

 

[user 40839]

Why not just get an AC motor and pulleys or chain/sprocket. You'll know the RPM.

True - but I'd have to buy an AC motor, whereas I already have this one!

But the continuous duty aspect has me thinking. While I obviously wouldn't be running this for hours, more like 3-4 minutes a couple times a month, it's still longer than the intended use. I've been searching high and low for info on this, but it seems (surprisingly, to me) that few, if any, folks have tried using one of these motors to run a mill. I did come across a post on some guy's blog where he said a friend used a garage door opener for a MLT stirrer, and didn't mention anything about it cutting out. However I did find something on usenet where a guy contacted the manufacturer of a garage door opener, and got a response back saying that it will operate 5 complete cycles before overheating, and then taking 45 minutes to cool down.

 

[user 40839]

Well, I just answered my own question. I ran the motor, without any sort of resistance, to see how long it would go

About one minute in, it started vibrating a little.

About two minutes, the capacitor started hissing and venting some sort of steam, at which point I unplugged it. It's going in the trash, and I'm ordering up a different motor!

 

[Bubba_Mustafa]

Yeah, 3-4 minutes *Shouldn't* hurt it. As to why they haven't been used, I'd guess most people don't replace the door openers until they stop working. Dead one probably have burnt out motors.

For the RPM: Have a bicycle with a speedo on it? Put the wheel on the output shaft and do a little math.

edit: oops Figured it would last a little longer then that.

 

[BrewBeemer]

I've got an old Craftsman opener I bet 1/3 HP also plus single frequency
signal now with a keyed switch for safety. It turns 1,100 rpm's.
Should I cycle it more than four up and downs the thermal switch will kick
in until it cools down again. A intermittent duty motor only beside a POS
in low quality construction overall. I have a MM3-2 waiting be powered at
at a slow 224 rpm's off a single Baldor motor worm gearbox unit that's in storage.

 

[user 40839]

I suppose I'd take a thermal switch kicking in over the capacitor spewing noxious crap any day of the week, Carl! But erm... I'll happily test that motor for you instead of having it in storage!

Anyone use a pump motor to run a mill? Sniffing around for a replacement, and came across this one:

Looks like it'll fit the bill without issue, right? 115 volts, 3/4 HP, 1725 RPM, capacitor start, continuous duty...?

 

[BrewBeemer]

Well ya got enough HP there for sure at 3/4 HP and cont duty. All the pump motors i've seen and worked with dealing with well pumps were rated at 3,450 rpm's not 1,750 rpm's. Dayton Grainger I bet it's a bushing not a ball bearing motor, no worries it will work great for your use.
I would belt it down by 7:1 ratio for 250 rpm's at the mill. JMO on this mill speed as i'll run mine slower. With a 1 1/2" motor and 12" mill pulley this will give you 218.75 rpm's, i'll have plenty of time to mill while heating water.

 

[user 40839]

Yeah, it's not a ball bearing motor, but what worries me is that I can't find a THING about a Dayton 9K830 motor ANYWHERE online, apart from the ebay auction, so I'd be concerned that the info on that panel is wrong somewhere/misprinted. I was surprised at the RPM of it, seeing that pump motors are, like you said, usually twice as fast. Which means if it's ACTUALLY 3,450 RPM, then my mill will be running at over 500 RPM, and... that's not a good thing!

 

[BrewBeemer]

Plug it in you'll know instantly if it's 1,250 - 1,750 or 3,450 rpm's.
Usually a pump motor would have end frame bolt holes for mounting as well a stepped centering lip to mount onto a pump frame aligning it concentric. If a center base frame a general use 1,725 - 1,750 rpm OTTOMH.

 

[user 40839]

Haha, yeah - but in order to plug it in and test it, I gotta buy the thing!

 

[BrewBeemer]

Ya don't need no stinking plug just poke the leads into an extension cord but first check to see if it's wired from the factory at 230 or 120 volt.
Be careful if you don't feel safe poking wires, not a problem for me being a electrician.

If this is your motor I just located hell it's a Procon pump motor, this correct what you have? Listed at $38. The pump is clamped to the motor and driven
by a flat blade drive dog in the motor and pump slot.
BTW it's a 1,725 rpm motor with no shaft to mount a pulley. Dayton 9K830 below.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150450651215

Here's Procon pumps to see the band clamp connection used to mate to your motor http://www.proconpumps.com/Products.htm#Series3

 

[BrewBeemer]

I was thinking centrigual like well pumps not positive displacement like Procon's is why the 3,450 rpm's.

 

[pickles]

I have a Gast vacuum pump for a laminating press that has a Dayton motor that is 1725 so its not out of the question. I run mine for up to 36 hrs straight pulling 22 in. Hg while when using slow set resin on laminated wood pieces. I haven't had any issues in the past 5 years.

 

[BrewBeemer]

Dang it Pickles ya made me go hunt down my pump i've got in storage off a job site. It's a Gast vacuum pump powered by a Doerr 1,725 rpm motor, 230 volt @ 4.5 amp, 115 volt @ 9.0 amps. Part of the tag is missing but I come up with 1/2 HP? It's heavy with that cast iron pump, Gast model 0822-V103-G271X. I saved it off the UC Berkeley demo job before it was headed to the dumpster. Many 1/2 to 3 HP cap start ball bearing blower motors saved also. Pack rat in me.

 

[maida7]

Not silly at all. I actually bought a high amperage, geared-down drill from Harbour Frieght. I wanted a new corded drill anyway. Well, it's not powerful enough to crush my grain. If I had bought a crusher, it would probably work. But my rollers are larger diameter and the extra torque needed to crush the grain makes the drill unusable. It started smoking right away.

So, not wanting to purchase ANOTHER drill, I started looking for alternatives. I ended up getting a nice gearmotor, unused, from work for free. Not all are that lucky. So I'd be interested in finding a method of using low-cost alternatives so that others can build their own motorized crushers.

Even if I didn't have the gearmotor, I'd still prefer to have a mounted crusher, as opposed to having to hang onto that drill the whole time. I crush about 6 lbs in just under 2 minutes. Fairly slow, but much better than using my hands.

Bottom line for me, saving money and "building stuff".

Harbour Freight drills are garbage. My cheap Ryobi cordless drill can power through any grain. And that's a cordless. I also have a big dewalt hammer drill that could crush grain until the cows come home. Really with a half way decent drill you should have more then enough power to run a mill.

 

[user 40839]

If this is your motor I just located hell it's a Procon pump motor, this correct what you have? Listed at $38. The pump is clamped to the motor and driven by a flat blade drive dog in the motor and pump slot.http://www.proconpumps.com/Products.htm#Series3

That's the one - and good spot on the lack of a shaft, with all my fussing about RPM and HP ratings, I completely missed the obvious. Feck that, I'll pass on it, since after 15 minutes of searching, I can't find the "add a shaft" doodad for sale anywhere!