Lot-O Polish Stage Issue

[Admin]

Aug 16, 2019 23:10:36 GMT -7 @adave said:

I picked up a Lot-O in the beginning of the year, and I've probably finished eight or so batches since obtaining it.  For the most part, I'm using the "standard" recipe as found here on RTH with just slightly less Borax when called for in stages.  Based upon what I've seen on the 'net, I think mine circulates material a bit more slowly than what I've seen in vids, but I haven't gone far enough to move the dowel to speed things up.  Nevertheless, I've still gotten good results.

My issue lately is with the polish stage.  I've seen others complain about the 120/220 stage being tough to manage, but I'm able to work my way through that.  For me, however, the polish stage has been the toughest to keep stuff moving and I couldn't get more than 24 hours in that stage in my last batch.

For the polish stage, I'll load up my barrel and water is drained off appropriately.  When I start up the Lot-O, the rocks will barely circulate initially.  But, as soon as I add my 1/2 tsp of polish, the contents of the barrel circulate as I would expect.  2 tsp of Borax are then added.  No issue here thus far other than stuff not beginning to move until grit is added.

As the 24 hour mark is approached and grit has worn, things REALLY begin to slow down to a creep.  Material is still wet and the slurry is not too thick.  But, there is almost no circulation of material.  With this last batch, I pulled stuff after 24 hours in polish as everything was pretty much standing still and no movement was taking place.  Yeah, it was shiny, but with the "short" run in polish, I feel like I'm not getting as much as I can in a finished product.

Has anyone else experienced this?  If so, how did you work through it?  I think I'm dealing with a (lack of) friction problem, as stuff doesn't really start moving in this stage until I add polish.  In a mixed batch of rocks, I'm probably near 30% of mixed ceramics in relation to the rocks.  Right now, I'm kind of at a loss in how to extend my polish time, but I've been fighting a losing battle thus far.

[Admin]

Aug 17, 2019 10:39:27 GMT -7 @adave said:

Aug 17, 2019 5:14:16 GMT -7 @saxplayer said:

I use only 1 TbL borax with any polish or stages except final burnish I use 2. Try that?

Perhaps that's something to try - bumping up the Borax dose to 1 TBSP at the start of the polish stage.  I cut back to 2/3 TBSP when I started using the Lot-O as it seemed to make things too thick, or so I thought.   Maybe that extra goo that is formed with the Borax helps to "grab" the rocks and helps to keep them moving.  Don't know, but it can't hurt to try.  Thanks.

[Admin]

Aug 17, 2019 21:29:07 GMT -7 @adave said:

Aug 17, 2019 19:56:51 GMT -7 @tomg said:

Have you tried spritzing with water? That's the fix in my UV-10 and my MT4 for slow action.

Thanks Tom, but it's not dry.  Remember, the first sign of any issue is upon startup of the polish stage when I turn on the Lot-O to add grit.  Nothing really moves until the polish is added, then things are fine (normal) for a while.  Water makes it worse when well into the stage.  I've tried. 

[Admin]

Aug 17, 2019 21:31:24 GMT -7 @adave said:

Aug 17, 2019 20:25:13 GMT -7 @rocnroll said:

I came across this by accident... I always seemed to over-water by spraying when I first started due to slowing of action. I would unplug, drain with hand over opening, put back in frame, and action would return. Now I turn the barrel. When action slows down, try turning the barrel 90 degrees...without losing contact with the frame. I pick up and pull forward while staying in contact with the front of frame and twist about 90 degrees. I will bet you see better action without adding water. Hope this helps.
Jeff A

Edit, this is for the Lot-O tumbler...

Thanks Jeff.  What you do with re-draining the barrel mid-stage is what I do to ensure I haven't over-watered.  So far, too-much water does not seem to be an issue, and material is wet.  I'll try your 90 degree rotation as well.  Thanks.

[Admin]

Aug 18, 2019 12:54:06 GMT -7 @therock said:

I will add this and I don't mean it to Nock the Lot"O" but the UV-10 and UV-18 is not near as Finicky to operate as The Lot "O's" which I have 3 of.  I can Load up  Both at the same time and I don't have to open the UV's only to move to the next stage The LOT"O"s are very finnicky with water amount and slurry In my opinion they work better with 3/4 TBL spoon of Borax and 1/2 to 1 teaspoon of grit. When I start off I use 10 sprays or sprits to make up for the powders added. I find each Day I need to add 10 Sprays or sprits of water and use a Stick to churn up Mixture. Like evary one else has mentioned the Slurry gets thick quickly and can damn near come to a stop. Normally I use 3 days for each stage 220, then 500, Then .3 micron. For Obstian I may go up to a week on that last stage.   

[Admin]

Aug 18, 2019 19:29:33 GMT -7 @adave said:

Aug 18, 2019 17:10:48 GMT -7 @jugglerguy said:

I don't see anything that you're doing wrong. If you suspect that your machine is running slower than normal, I would suspect that is the problem. My polish stage runs just like the other stages. I use 1 TBSP of borax, but I don't remember noticing it running slower than normal before adding borax.

Thanks Rob.  What about before you add your polish?  Is it running any slower before the abrasive is added?  That's where I first noticed any sign of an issue.  With just water-wetted rocks, they don't move well after the machine is turned on.  Add polish, and then all is well until about 20 hours pass (at least that's the way it was with the last batch).

The more I go through this (mental) exercise, a phone call to the company is probably in order.

[Admin]

Aug 18, 2019 20:03:53 GMT -7 @adave said:

Aug 18, 2019 19:36:18 GMT -7 @saxplayer said:

Mine definitely doesn’t run well until I add borax or grit or polish. It helps grip the rocks somehow.

Thanks Grant.  Nice to see I'm not the only one. 

[Admin]

Oct 23, 2022 8:03:59 GMT -7 @jamesp said:

RTH taught me to use AO. Never looked back. Others have used tin and cerium oxide and had great results. If the polish is hard enough to polish a hard rock to a 1 micron surface level then all should work out fine.

Notes on the flexibility of AO:

It's been mentioned over the years(and my experience) that(Rock Shed's) AO 500 will reduce in size in a Lot-O and other brands of vibes to polish sized particles in 3 to 7 days depending on conditions. Note that AO 500 doesn't reduce as well in a rotary, but one more rotary step of polish will bring a fine polish. That is what sold me on AO.

The only proof that the AO 500 is breaking down unless someone looked at it under a microscope is the 1 micron+ level polish AO 500 lays down in those vibes.

For that level polish to happen the AO 500 sized particles have to reduce in size in harmony from their 35 microns size to .5 to 1 micron size which is amazing. For reference 35 microns = 500 grit, 1 micron = 14,000 grit, and .5 microns = 50,000 grit.

Playing devil's advocate comparing diamond, diamond 500 would never meet that size reduction performance because it is so much harder than aluminum oxide and all other abrasives. Diamond is noted for its ability to not wear down and it would probably maintain its 500 size for months in a vibe and no polish would happen for a very long time.
By the same token 1 micron diamond polish would likely not reduce from a 1 micron/14,000 polish to a .5 micron/50,000 grit polish. IMO many members tumble polishes easily move into the 50,000 to 100,000 grit level polishes due to reduced size abrasives. Jewelers commonly use .5 micron/50,000 diamond paste on their work. 50,000 and 100,000 grit polishes are those that are just blow you away shiny. There is no other way to have a dead wet shine unless the worked surface is .25 to .5 microns. Unakite and other Mohs 6 or less rocks are more of a challenge to get a high polish on.

Back to the tin oxide, a great test would be to run tin oxide 500 in a Lot-O and see if it will reduce in size to the point it will polish a batch like AO 500 does. Nice to be able to skip fine steps when able. If an any type of tumbling abrasive will go to(or close to) polish level from a much larger size it is a fine abrasive.

This would be an example of a .25 to .5 micron polish and it was accomplished by running giant AO 22(!) in a vibe for 10 days. A testimony as to how flexible aluminum oxide can be:



PS Chad it is real tricky taking photos to compare polishes. I finally figured out how. Best is to have lots of light and excellent reflection as in the above photo. The one pound rock was run in a vibe in 100% quartz pea gravel with no other larger rocks to possibly damage the delicate polish surface. It is not required to run a rock in 100% media to get a super polish but it does reduce chances of a damaged polish especially when running a 1 pound rock. Some of the highest polishes are gotten when the batch is all small hard agate type rocks.

[Admin]

Oct 23, 2022 8:45:28 GMT -7 @jamesp said:

@starguy Garnet, especially high grade almandine breaks all kinds of records for being one of the 'toughest' abrasives on earth. Rocks can be hard but they also have another property called 'tough'. The Mohs test is ok for testing hardness and toughness. The Knoop test is much better for testing toughness. This issue comes into play when sandblasting and impact tumbling(like in a rotary) is involved.

Almandine garnets can be shot at tough steels for many cycles before breaking down to smaller pieces. Silicon carbide is much harder and cuts faster but shatters like glass into tiny particles after being shot once rendering it useless for such an application after that.
That is why water jet drilling machines use good ole almandine garnet abrasives for jetting say a long 4 foot long tiny hole in a chunk of tool steel. They toss the almandine garnet when it rounds and smooths to the point it won't cut well. Granted some of the garnet particles do crack into smaller pieces.

I remember those large garnets you tumbled. That must be a slow process. If tin oxide polishes those garnets that says a lot about tin oxide.