Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Sept 29, 2015 8:50:56 GMT -5
You know, I knew that about the amps ratings....brain phart on my part. Well, I'm running up against a wall finding a 1/8hp motor with a 1/2" shaft. Most of the smaller motors that I'm finding are 3/8" or 5/16" shaft.
It seems that for pulleys, pillow bearings, and such, that the cut-off point (from what I can tell) is 1/2"...anything smaller seems to fall in the "specialty size" category and are hidden in the secret chamber of King Tut's tomb. Surplus Center seems to stop at 1/2". I've searched eBay mostly for motors so I might find what I'm looking for elsewhere, but the few other places that I've looked I haven't found anything yet. 1/4hp and 1/2hp can be readily found with 1/2" and larger shafts...just not the smaller hp motors.
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Sept 29, 2015 9:13:28 GMT -5
Hmm, I just found some 3/8" bore pulleys on Granger...
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Sept 29, 2015 11:29:54 GMT -5
Ok, I left the humble Model A running last night at the shop sitting on the floor. I figured I'd give it a dry run and maybe "polish" the bearings up a bit after I had oiled it. I had the empty barrel rolling on it, barrel weighs 3.05#. I came in this morning to see the barrel not rolling but I heard a hum coming from the motor. I figured it had burned out or in the process of burning out...it was dimly lit where I had the tumbler and when I looked a little closer I saw that the motor shaft was turning. The belt had broke. Maybe from just being old? I don't think there was a malfunction as the barrel and rollers all looked good. it was simply a break in the rubber o-ring belt...kind of a bird's beak on one side of where it broke and a point on the other side of the break that mated up nicely. <sigh>
Well, I ordered a couple of belts from The Rockshed for a Model B which is the thicker belt...I'm hoping these work being as I measured my belt at 12-1/4" and The Rockshed says there's are 12-1/2". We'll see.
At least a broke belt is better than a locked up motor...
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Sept 30, 2015 9:11:26 GMT -5
Ok, I got some belts that I'm going to try on the Model A today. Hopefully the overnight run helped polish the bearings up and maybe even freshen up the brushes in the motor and improve motor performance a bit. I'm not sure how long it ran before the belt broke or if running it helped anything. Back to the motor search for a diy tumbler... What is a range of reasonable rpm's to consider? What specs should be considered most important? Jim, your 1/8hp motor is turning a 40+ pound barrel. Do you think a 1/15 or 1/20 hp motor will do ok on a 20 pound tumbler? I'm thinking that for now I'll build out of 3/4" rods and hardware being as it doesn't look like much (if any) cost savings by dropping back to 1/2". But, for now, I'm going to go with a lighter hp motor to keep electricity costs reasonable and because I don't anticipate tumbling loads as large as yours...yet. With the framework built for heavier work I can add a bigger motor if later own I decide to go BIG.
|
|
|
Post by johnjsgems on Sept 30, 2015 11:50:54 GMT -5
As far as the motor amps, if it is double it is dual voltage. The amps you listed would indicate two speeds.
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Sept 30, 2015 11:56:40 GMT -5
Well, I went to put the new belt on the Model A this morning and was surprised when I lifted the "empty" barrel off of the tumbler...it actually was filled to the max with rocks...duh, I was wrong when I said it was empty earlier...oops!!! Ah well, I removed the barrel and slipped the belt on and put the loaded barrel back on the rollers. I really wasn't expecting it, but the tumbler started spinning the loaded barrel without hesitation. I guess that dry run must of reformed a cap or at least knocked some rust off of something. I'm letting it run now with the load...if it keeps going I'm going to call it "good" and prepare a load of rocks up for coarse grinding!!!
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Sept 30, 2015 14:52:01 GMT -5
The base unit with 3/4 shafts sets you up for future expansion. I can attach most any motor to it, and belt within reason. thank the big wood box under it. Even if building a 1/50 HP tumbler I would still go with the wood. Sometimes 1/2 bearings more than 3/4 inch. Small stuff can be more costly. The heating and air companies my have the used 1/8 or 1/6 HP. If it comes out of a commercial roof top A/C it is a high grade motor. Not all created equal. Some of them have 4-6 fan motors. Scrap yards love them. They want the copper and aluminum out of them. Try a scrap yard...
A lot of small motors(1/100-1/15) have bushings instead of bearings. They are usually cheaper motors.
I have run the 1/2 HP by itself and it costs. I have run the 1/8 by itself and hardly see the bill go up. As said, they are on separate meters.
I replaced the 1/2 with a 1/3 just to save $$$ on the 4 barrel tumbler.
I do tilt both so the barrel hits the side roller. Only one side roller on both of them, the down hill side. Pillar block bearings OK with slant, not sure about bushings. Pillar blocks w/grease fittings made for heavy loads, nice to pump grease thru just to push any grit out.
It's all up to you on capacity though.
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Oct 1, 2015 9:06:37 GMT -5
Here's a screen capture of a little spreadsheet I did on different amperage motors and their energy use. Probably got some errors in there, but seems to work out pretty close. If anybody is interested in it I might can figure out a way to post it somewhere for download. ImageHPElectSpreadsheet by Intheswamp, on Flickr
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Oct 1, 2015 9:19:43 GMT -5
The base unit with 3/4 shafts sets you up for future expansion. I can attach most any motor to it, and belt within reason. thank the big wood box under it. Even if building a 1/50 HP tumbler I would still go with the wood. Sometimes 1/2 bearings more than 3/4 inch. Small stuff can be more costly. The heating and air companies my have the used 1/8 or 1/6 HP. If it comes out of a commercial roof top A/C it is a high grade motor. Not all created equal. Some of them have 4-6 fan motors. Scrap yards love them. They want the copper and aluminum out of them. Try a scrap yard... A lot of small motors(1/100-1/15) have bushings instead of bearings. They are usually cheaper motors. I have run the 1/2 HP by itself and it costs. I have run the 1/8 by itself and hardly see the bill go up. As said, they are on separate meters. I replaced the 1/2 with a 1/3 just to save $$$ on the 4 barrel tumbler. I do tilt both so the barrel hits the side roller. Only one side roller on both of them, the down hill side. Pillar block bearings OK with slant, not sure about bushings. Pillar blocks w/grease fittings made for heavy loads, nice to pump grease thru just to push any grit out. It's all up to you on capacity though. Yes, if I build I will definitely be going with 3/4" hardware on the box. No difference really in cost. ...and years from now when I'm dead and gone someone can look at it and wonder what the heck it was!!!! Motors, though, from roof-top commercial AC units...they're not 220v stuff? There's an appliance repairman in town that keeps junk washers, dryers, and does a little AC work, too. I'll check and see if he thinks he might have something. I have a few motors stuck here and there but they're all too big or high-amped. I pulled one from a squirrel cage and it was rating up at 7 amps and wasn't that big of a motor!!! The others are 1/4hp or larger. I'll just have to keep looking. Some of the smaller motors also have smaller shafts. Any way to turn a 3/8" shaft into a 1/2"? Tilting the tumbler... I noticed when I started up the old Model A that it must have been unlevel as the barrel moved away from the pulley. For what I was doing I simply folded up a piece of cardboard and slipped between the end of the barrel and the frame of the tumbler...not a permanent fix, but it worked for my test driving. I may just epoxy a piece of formed wood to each end of the tumbler frame...after the barrel burnishes it for a while I don't think there would really be much of a wear or drag issue there...or I'll figure some rollers out. For rollers I was thinking of drilling a hole in a block of wood, attach to side of frame, drill hole vertically down into wood and slip the shaft of a roller from a roll-door into it...
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Oct 1, 2015 9:48:40 GMT -5
Don't trip about the motor. The big wood frame will allow easy change to another motor. That's why you should build it (on blind faith). Get you a cheap 1/4 HP washing machine motor till you can find better. Change it out later.
About 70-80% are 220 VAC, but 110 VAC are often run off the 110 VAC transformer control circuit.
Those 1/8 HP are big for their size-big bearings/well built/full of good copper. Efficient, powerful and run cool. Most 3/8 shaft motors are budget/cheaper. Poor seals.
A fan is cruel to motors, tough constant duty. Exposure to weather, difficult to access in roof tops. Reliability paramount.
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Oct 1, 2015 10:20:52 GMT -5
Don't trip about the motor. The big wood frame will allow easy change to another motor. That's why you should build it (on blind faith). Get you a cheap 1/4 HP washing machine motor till you can find better. Change it out later. About 70-80% are 220 VAC, but 110 VAC are often run off the 110 VAC transformer control circuit. Those 1/8 HP are big for their size-big bearings/well built/full of good copper. Efficient, powerful and run cool. Most 3/8 shaft motors are budget/cheaper. Poor seals. A fan is cruel to motors, tough constant duty. Exposure to weather, difficult to access in roof tops. Reliability paramount. That's what I'm thinking right...get something working and then tweak it. I've been looking at motors with 1/2" shafts mostly. I found a 1/8hp that looks about new, guy wants $60 for it...fair price? Only thing is that it's like 650rpm... ?
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Oct 1, 2015 10:30:02 GMT -5
How important is the posi-traction dual-pulley setup? In looking at yours it looks like the belt is missing. What I'm thinking is having the rods extended for those pulleys takes away ~3 inches of roller length/capacity. I'd like to go ahead and put an order in with SC but I'd like to get everything shipped together and I'll still need pulleys....but, I haven't got a motor to mate them to, yet. We'll get there, though!!!!!
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Oct 1, 2015 11:39:38 GMT -5
Ed, the slower the motor the smaller and cheaper the big pulley. However, you are stuck with a slow motor replacement or else you have to get a bigger pulley for 1725 RPM Motor.
On my machine:
1125 RPM motor = 23 RPM 1725 RPM motor = 30 rpm
Either of those speeds are acceptable for barrel speeds. A 650 RPM motor would be like 13 RPM w/my pulley-too slow. And barrel diameter a factor.
That's why i mention ordering the big pulley last, it's size dictates the barrel speed. Ratio discussions best had after you have a barrel and motor. 650 RPM throws a loop, ha. Was not expecting that one.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Oct 1, 2015 11:46:00 GMT -5
Posi traction a must. You will cook your barrel if the morning dew gets on it and causes it to slip. Or water gets on it from leaking seal/gas. Or if you have a barrel 1/2 to 5/8 full slippage is more likely. Never had a bare shaft set slip with posi. Always without. Yes, shafts long enough for end posi pulleys, barrels, and one shaft for the drive pulley. At least 3 feet to 42 inches, cut them off after if anal
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Oct 2, 2015 10:39:30 GMT -5
I see what you mean about probably upgrading later to a higher speed motor and being stuck with a small pulley on the drive roller or having to buy a larger pulley. I've found where I can order sleeves to move a 3/8" shaft up to a 1/2" size so that standard pulleys, etc., will fit. That opens up the motor pickings a bit for me...I'd rather have a 1/2" shaft from the git-go but if I have to make do for a while I have an option for a smaller shafted motor. I'll figure on going with positraction as that sounds like a good idea. My tumblers will be out of the weather, but at times might be in an open shed, so yes, fog/dew could be an issue. The rods that I'm looking at are 3' long...that should still easily leave 2-1/2' of rod capacity. I'm thinking of building the frame deep enough to handle another set of rollers...who knows where I might end up at with this.
|
|
indiana
spending too much on rocks
Member since October 2015
Posts: 285
|
Post by indiana on Oct 2, 2015 11:12:45 GMT -5
You know, I knew that about the amps ratings....brain phart on my part. Well, I'm running up against a wall finding a 1/8hp motor with a 1/2" shaft. Most of the smaller motors that I'm finding are 3/8" or 5/16" shaft. It seems that for pulleys, pillow bearings, and such, that the cut-off point (from what I can tell) is 1/2"...anything smaller seems to fall in the "specialty size" category and are hidden in the secret chamber of King Tut's tomb. Surplus Center seems to stop at 1/2". I've searched eBay mostly for motors so I might find what I'm looking for elsewhere, but the few other places that I've looked I haven't found anything yet. 1/4hp and 1/2hp can be readily found with 1/2" and larger shafts...just not the smaller hp motors. Metal down to 1/4": www.mcmaster.com/#pulleys/=z6yvasNylon in 1/4", 5/16", 3/8", 1/2": www.mcmaster.com/#pulleys/=z6ywegShipped out of Chicago, I got my order in southern Indiana in 1 day for $6 shipping.
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Oct 2, 2015 12:53:22 GMT -5
Ok, I went and weighed the loaded barrel, here is some pertinent data: 7.2 pounds total loaded weight 3.05 empty pvc barrel 3.25 rocks 0.50 smalls 0.40 water and grit The Model A is percolating along quiet nicely. I checked the motor with the temperature gun and it read just under 160F as it did when I first checked it a few days ago during it's "break-in" cycles. Something I noticed this time was that the barrel seemed warmer than ambient so I hit it with the temp gun. The end of the barrel closest to the pulley and motor was sitting at 92F...about 8-1/2 inches to the other end away from the motor the temperature was 82F. Looks like the motor is warming the barrel and contents up...at least it won't freeze.
|
|
Intheswamp
Cave Dweller
Member since September 2015
Posts: 1,910
|
Post by Intheswamp on Oct 3, 2015 23:51:32 GMT -5
When using Chuck's Pulley/RPM calculator, is the "Datum size" on Surplus Center's website what you should go by when selecting the calculated pulleys?
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Oct 4, 2015 5:22:09 GMT -5
When using Chuck's Pulley/RPM calculator, is the "Datum size" on Surplus Center's website what you should go by when selecting the calculated pulleys? if you are using 'A' belts it is best to use datum. For 'B' belts you will be close enough using OD. Mine is 2.65(motor)/13.75(big pulley) X 1.0(shaft)/7.5 barrel) X 1125 RPM = 28.9 RPM for 6 inch PVC. Used OD's on this calculation for 'B' belt Looking back, motor pulley effects speed reduction a lot. 2.45 OD motor pulley has a 1.8 datum for A belt, 2.2 datum for B belt. 1.8/2.2 = 19% speed reduction, A belt vs B belt. So you should use A belt to reduce speed most. For 6 inch PVC barrel 25-40 RPM seems to work fine. And a smaller 3/4 inch shaft slows it down a lot too. .75/1.0=25% speed reduction.(no rubber on shafts) Big tumbler is: 1.9/18.00 X 1.5 shaft/7.5 X1725 RPM = 36.3 RPM for 6 inch PVC. Used 'A' belt datum for 'A' belt This tumbler has two sets of shafts. One set at 36.3 RPM and the other shaft set is like 55 RPM or 36.3 RPM depending on pulley(changeable) 55 RPM for faster tumble in coarse for agates only. i used the giant 18.75 inch SC pulley because of the fat 1.5 inch shaft and 1725 RPM motor on this tumbler. 3/4 shaft vs 1.5 shaft-.75/1.5= 50% reduction, so smaller shaft(as mentioned) helps slow tumbler a lot.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Oct 4, 2015 5:27:48 GMT -5
Tumbler is a double reduction machine. Motor pulley/big pulley times shaft diameter/barrel diameter times motor RPM = barrel RPM
And 6 or 8 or 10 or 12 inch barrel is ok to run because 12 spins slower than 10, 10 slower than 8, and 8 slower than 6.
Bigger the barrel, the slower it rotates. No matter. They all have the same surface speed. Big barrels should rotate slower than small barrels to avoid damaging rocks.
|
|