LOT-O motor VS concrete vibrator motor - VIDEO

[Drummond Island Rocks]

Finally had a chance to make a quick video comparison of the retro fitted lot-o using a 30W concrete vibration motor. It took some tweaking with the weights but this is as close as I could get the two versions. I did not need to do this but I had enough extra parts laying around so I did it just out of curiosity. You will want sound on for the video.

I should add that both are much quieter when the cap is on the barrel.

Rocks are in 120/220 and had about 2 hrs of run time time get a decent slurry before making the video

I will do a temperature check after a few hours



I also spaced the motor away from the frame to try to avoid heat transfer



Chuck

[Jugglerguy]

Looks and sounds the same, now you'll have to run a batch of rocks in it just to make sure.

How did you adjust the weights? I assume they're under the covers on either end. Do they move in and out from the center?

[Drummond Island Rocks]

Jan 18, 2023 18:01:46 GMT -5 Jugglerguy said:

Looks and sounds the same, now you'll have to run a batch of rocks in it just to make sure.

How did you adjust the weights? I assume they're under the covers on either end. Do they move in and out from the center?

I'll detail that part when I am confident I have it right. The barrel is full of previously polished bahia and carnelian agates. I will run the batch per my normal procedure using this setup. I think it looks really close.

The only hang up I could see would be that I have never used this frame and mount. Also did not play with dowel location so there are tweaks that could be made there.

EDIT: I also wonder a bit about the original motor have two bolts attached to the upper piece of steel cantilevered out and two mounted behind the barrel. Now all four mount points are behind the barrel. Not sure if that would in turn effect overall motion.

Chuck

[Drummond Island Rocks]

Jan 18, 2023 18:01:46 GMT -5 Jugglerguy said:

Looks and sounds the same, now you'll have to run a batch of rocks in it just to make sure.

How did you adjust the weights? I assume they're under the covers on either end. Do they move in and out from the center?

It comes with 5 weights per side. They are kind of indexed so they can be pivoted at different angles. I had to remove three weights per side to keep it from vibrating so violently that it would have tore out my bolts, lol.

Chuck

[jimgsmith]

Great job! Looking forward to following your progress as I think many others are as well!

[chris1956]

Thanks for the post.  Could you do a noise comparison with the cap on the barrel?   I think a lot of the noise comes from inside the barrel and it would be interesting to see if the noise difference is greater with the cap on.   Also, what did you use for the spacer between the motor and the frame?   My similar set up has been running for about 3 weeks now without any real issues.   

[hoolligan1938]

Chuck - Great posting! Since you are doing so much research on this conversion could you continue to let us know how things are progressing. Thank you for all your efforts. I'm sure there are many of us who have the Lot-o and want to keep it going.

Jim

[ataraktos]

Jan 18, 2023 18:01:46 GMT -5 Jugglerguy said:

Looks and sounds the same, now you'll have to run a batch of rocks in it just to make sure.

How did you adjust the weights? I assume they're under the covers on either end. Do they move in and out from the center?

it's nice to have something with no exposed moving parts ... when my daughter was about 2 1/2, she was out, peaking in the lot-o with me. she dropped some treasure she was holding (might have been a peach pit or something) and bent down to grab it before i could stop her. lot-o fan "grabbed" her hair ... it was a pretty terrible experience!

[Drummond Island Rocks]

Jan 19, 2023 12:53:10 GMT -5 ataraktos said:

it's nice to have something with no exposed moving parts ... when my daughter was about 2 1/2, she was out, peaking in the lot-o with me. she dropped some treasure she was holding (might have been a peach pit or something) and bent down to grab it before i could stop her. lot-o fan "grabbed" her hair ... it was a pretty terrible experience!

Yikes, That is horrible and stuff like that happens in an instant.

Lapidary tool's from the 70's were notorious for open pulleys and belts and 90% of the homebuilt tumblers I see have all the moving parts exposed. I am still in the automotive field and spent 20 yrs as machinery designer so safety has always been a big part of my job. When I designed my tumbler and my flat lap stand both were made to have all the moving parts covered up.

Having run the lot-o for 10 yrs I have brushed up against those fans while they were running at least a dozen times and every time caught me off guard.




Chuck

[ataraktos]

Jan 19, 2023 13:03:51 GMT -5 Drummond Island Rocks said:

Jan 19, 2023 12:53:10 GMT -5 ataraktos said:

it's nice to have something with no exposed moving parts ... when my daughter was about 2 1/2, she was out, peaking in the lot-o with me. she dropped some treasure she was holding (might have been a peach pit or something) and bent down to grab it before i could stop her. lot-o fan "grabbed" her hair ... it was a pretty terrible experience!

Yikes, That is horrible and stuff like that happens in an instant.

[...]
Having run the lot-o for 10 yrs I have brushed up against those fans while they were running at least a dozen times and every time caught me off guard.

Yes, she must've been closer to 3 1/2 ... we were just talking about it, and she was like "I REMEMBER!" luckily, she was close/short and bending down to be even closer because it pulled her in, bumped her forehead against the cement paver! and the worst was like, turning it off didn't solve the problem, because her hair was wound up, tight.

And yes, ever so often the fans "get" my fingernail or even the spray bottle, just a touch and it's always scary.

Daughter still loves rocks though. (She always holds her hair back, though, when we peak in the lot-o!)

Your workshop is beautiful, btw! =)

[Drummond Island Rocks]

A quick little insight into noise levels of stock lot-o motor vs concrete vibrator motor. Both motors are practically silent when the offset weights/fans are removed. All of the noise is generated from the shaking of the lot-o base and the rocks moving. If the new concrete motor is tuned to the same vibration level as the original lot-o motor the noise level will also be the same.

Chuck

[bbrooker88]

I am wanting to install one of these motors to my Lot-O, but I ordered a 40W version instead of 30W. Any idea how much of an impact that would make? I could either return the motor for a 30W, or I was thinking of spending the money I'd pay to ship the 40W back and get a speed control unit so that I can dial-in just the right amount of vibration--instead of fiddling with the weights. Just not sure how much more powerful a 40W motor would be vs a 30W.

Any thoughts?

[mgroothuis]

This makes me want to buy the 30W motor even though my current Lot-O is running fine. You never know what happens to future parts/availability in this day and age.

[Drummond Island Rocks]

Jan 22, 2023 15:36:31 GMT -5 bbrooker88 said:

I am wanting to install one of these motors to my Lot-O, but I ordered a 40W version instead of 30W. Any idea how much of an impact that would make? I could either return the motor for a 30W, or I was thinking of spending the money I'd pay to ship the 40W back and get a speed control unit so that I can dial-in just the right amount of vibration--instead of fiddling with the weights. Just not sure how much more powerful a 40W motor would be vs a 30W.

Any thoughts?

I honestly do not how the wattage of the motor equates into the amount of vibration but I am sure it does. The 30W comes with 5 weights on each side pre installed and I had to go all the way down to 1.5 per side to calm it down enough to use. So if 40W is stronger I am not sure what adjustments would minimize the vibration enough. There is a bare minimum of one weight per side.

Chuck

[chris1956]

I don't know how the wattage difference would affect the vibration amount either.  But the Drummond Island Rocks post about the weights has raised a couple questions.   The attached photo shows the weights on the concrete vibration motor I bought.  I eventually increased the setting to the third peg position to get the vibration I needed.  The way I interpreted the motor manual was to rotate the outer two weights to get the vibration amount you wanted.  Can you explain what you mean by the 1.5 weights per side?   

The motor manual indicates that the minimum vibration setting is with the outer two weights directly opposite the inner three weights (2.5% of maximum vibration) but I couldn't figure out how to get the weights "fixed" at that position.  

[Drummond Island Rocks]

Jan 22, 2023 16:49:57 GMT -5 chris1956 said:

I don't know how the wattage difference would affect the vibration amount either.  But the Drummond Island Rocks post about the weights has raised a couple questions.   The attached photo shows the weights on the concrete vibration motor I bought.  I eventually increased the setting to the third peg position to get the vibration I needed.  The way I interpreted the motor manual was to rotate the outer two weights to get the vibration amount you wanted.  Can you explain what you mean by the 1.5 weights per side?   

The motor manual indicates that the minimum vibration setting is with the outer two weights directly opposite the inner three weights (2.5% of maximum vibration) but I couldn't figure out how to get the weights "fixed" at that position.  

I have used the lot-o non-stop for over 10 yrs so I know what the optimal motion is. I dialed the weights to 100% match one of my original lot-o's which still runs fine. Give it two more days and I'll be posting a finished batch from the modified lot-o.

The shaft is "D" shaped so one weight has to be used on each side and is not adjustable in location due to the "D" shape. I ended up removing 3 weights per side. Removing 4 weights did not leave enough vibration. I rotated the 2nd weight around at every possible location and half way seemed best. Keep in mind the quality control at Callaway is questionable so I have three lot-o's and not even the frames let alone the dowel locations are common amongst them so every one will probably require some tweaks.

The loto I used to compare this to is one that has won two world rock tumbling championships and has 500 completed batches on it so I am comparing it to a known correct lot-o.



Chuck

[chris1956]

Thanks Chuck.  It is interesting that the weight arrangements are similar but different. 

Chris

[bbrooker88]

I returned the 40W motor and got the 30W (for some reason the 30W was $10 more). I installed the motor and adjusted the weights as pictured. When I plugged it in I was totally blown away at the result. It was quieter than I think it originally was, and the rocks appeared to have a better rolling action with what seems like less vibration of the frame. How long it will last this way, who knows, but for $50 (including the plug and nuts/bolts/washers) this is far and away the way to go when you have to replace a $150 Lot-O motor. The bearings on mine had worn out and sounded like a small airplane engine!

Thanks for this super helpful post!

[mgroothuis]

Feb 5, 2023 16:08:20 GMT -5 bbrooker88 said:

I returned the 40W motor and got the 30W (for some reason the 30W was $10 more). I installed the motor and adjusted the weights as pictured. When I plugged it in I was totally blown away at the result. It was quieter than I think it originally was, and the rocks appeared to have a better rolling action with what seems like less vibration of the frame. How long it will last this way, who knows, but for $50 (including the plug and nuts/bolts/washers) this is far and away the way to go when you have to replace a $150 Lot-O motor. The bearings on mine had worn out and sounded like a small airplane engine!

Thanks for this super helpful post!

Great! I also ended up buying one of these motors just to have on-hand if my current Lot-O dies.

[dillonf]

Thank you for this post! I just bought a lot-o and have only done 3 polish runs in it, but I am already planning for when the motor goes. I am looking forward to hearing the details of your build. My lot-o cycles way slower than the one in your video.