HuntingHuron
starting to shine!
Member since October 2020
Posts: 39
|
Post by HuntingHuron on Mar 31, 2021 18:01:30 GMT -5
I've been running a 33B for half a year now - no issues. Was excited to buy a brand new QT-66. I'm now able to tumble more large rocks and "increased production".
I've run into an issue though. About 80% of my rocks end up being chipped or have tiny gouges. I'm wondering if my including a fair bit of small pea-size material is the issue. Maybe I should consider sticking with larger stones (still a mixture of sizes of course) for the QT-66 to avoid the crushing of smaller stones and leaving the smaller ones for the 33B. What is the right volume to fill the QT-66 - 2/3 like the manual says? How much water is appropriate? Hard to say whether or not to trust the manual.
Question 2 - I'm assuming others have used the QT-66 from stage 1 to polish (?) My "chipping" experience has made me a bit nervous about potentially ruining a batch later on. Mind you the plastic pellets should likely cushion the blow at the latter stages I'm guessing.
Just wondering about the experiences of other QT-66 owners
|
|
lordsorril
freely admits to licking rocks
Member since April 2020
Posts: 766
|
Post by lordsorril on Mar 31, 2021 20:58:40 GMT -5
What stones are you tumbling together and what are your pea-sized stones made out of? There is a world of difference between materials.
|
|
standles
spending too much on rocks
Well all I got was a rock ... Cool!
Member since February 2021
Posts: 325
|
Post by standles on Mar 31, 2021 21:56:19 GMT -5
Random thought... with larger bbls there is more room for rocks to crash into each other. This would mean slurry consistency and fill lvl with sizes matters more.
|
|
|
Post by greig on Mar 31, 2021 22:14:58 GMT -5
Some material chips more easy than others (eg. feldspars). You can usually hear when rocks are crashing. I use plastic beads (because I have a huge box of them), but am not a big fan and prefer ceramic media. I have a feeling that they tend to float, so might not be at the bottom of the barrel where we need them (ie. where the rocks do the most rolling).
I try to fill my barrels with water just below the top level of the rocks. Too much water makes the rocks swim. Too little and they will crash.
I don't think the size or quantity of your rocks matters. It might matter if the small rocks are significantly harder than the large rocks.
Greig
|
|
|
Post by Starguy on Mar 31, 2021 23:09:01 GMT -5
greig is right. Listen to your tumble. I don’t think you can have too many small rocks in your batch.
|
|
quartzilla
Cave Dweller
Member since April 2020
Posts: 1,215
|
Post by quartzilla on Apr 1, 2021 7:21:43 GMT -5
Where did you purchase the 66 from? I’ve been waiting forever for them to show up on RockShed.
|
|
HuntingHuron
starting to shine!
Member since October 2020
Posts: 39
|
Post by HuntingHuron on Apr 2, 2021 13:18:39 GMT -5
Thanks all, for your input. Some good points. I think I'll need to pay more attention to the hardness of the rocks for the QT-66. I used a mixture of rocks for pea size. I'm assuming if I stuck to pea size quartz it might be a better idea (?) Seems like the 33B is a bit more forgiving (at least from my experience) because I used the same mixture. Maybe I'll even toss in some plastic as insurance in the QT-66 next time. quartzilla - I picked up the QT-66 about a month ago. I live near Toronto, and bought mine at a store in the small town of St. George, Ontario - likely the 2nd last one available in Canada. There was one left, and the store was surprised when they received a request to ship one the previous week out to British Columbia - the Canadian west coast. I'm aware of the Lortone Tumbler shortages. My understanding is that there is a supply chain issue. If I have my story straight, I believe they are looking for a different motor supplier. Maybe someone can confirm whether or not I am wrong.
|
|
HuntingHuron
starting to shine!
Member since October 2020
Posts: 39
|
Post by HuntingHuron on May 5, 2021 17:25:18 GMT -5
Just wondering if anyone uses plastic media for stage 1 (rough stage). How much of a negative impact would it have on the grinding process at this stage? greig were you referring to this stage in your comment above?
|
|
Wooferhound
Cave Dweller
Lortone QT66 and 3A
Member since December 2016
Posts: 1,423
|
Post by Wooferhound on May 5, 2021 20:06:45 GMT -5
Filler for the first stage should be More Rocks. Plastic will slow everything down and waste your time and plastic. Ceramic is not necessary unless you don't have enough smalls to get into the cracks.
|
|
|
Post by Garage Rocker on May 5, 2021 20:17:59 GMT -5
I only run first stage in my QT66, so I have never used plastic pellets. There is no need to cushion in that stage and the pellets just take up space. I normally throw in my tile saw scraps and I usually have some heavily fractured rocks I've busted up for smalls.
The machine, though, is a workhorse. It's my favorite.
|
|
HuntingHuron
starting to shine!
Member since October 2020
Posts: 39
|
Post by HuntingHuron on Sept 2, 2021 18:54:20 GMT -5
Another issue I've run into is the some of the stones with flat surfaces, or ones that I've slabbed on my tile saw tend to stick to the bottom of the 6lb barrel- in the "muck". So one surface of each of those stuck rocks does not benefit from the tumbling process during that stage. With all that rotating and movement inside it's hard to believe that those stones don't seem to some how get knocked free. Anyone else run into that issue before with the QT66?
The one way I've dealt with it is to fill the barrel with these "flattish" stones. I figure that there is only so much surface area at the bottom of the barrel for a limited number of stones to get stuck to.
|
|
rrod
having dreams about rocks
Member since December 2020
Posts: 72
|
Post by rrod on Sept 2, 2021 21:08:50 GMT -5
Heavy stones will absolutely destroy brittle material. Bigguns get flung around just as fast as small ones (the tumbler maintains a constant rotational rate), so more heavy stones means bigger collisions. You can test this out: pick two roughly equivalent 1” pieces of something chippy like feldspar, then run one with nothing but, say, 2” garnets, and the other with only 1/4” pea gravel (no grit needed for this test). Leave em for 2 weeks and see which stone comes out alive. While using lots of smalls and higher fill levels will help prevent chips, it has downsides. Grit breakdown takes longer (or your have to use finer grit), and more grit gets wasted wearing away the surface area of the smalls, rather than your nice rocks. This means that insuring non-chip results on chippy rocks can mean much longer tumble times. I have a large (4x2x1”) labradorite that is coming along beautifully but will probably take 3 months of stage 1, and it will only take one lapse in perfection to screw it all up Also important to note that many people use SiC for everything before polish, but AO is *much* better at highlighting cracks/pits/gouges due to the white color. That means that sometimes it appears that a rock got messed up during the polish stage, but in actuality the imperfections you see were always there. This is compounded by the fact that it’s easy to never see a rock dry except after polish, and wetness is also good at hiding bad features too.
|
|
|
Post by Bob on Sept 3, 2021 14:06:42 GMT -5
What stones are you tumbling together and what are your pea-sized stones made out of? There is a world of difference between materials. I second this query and suspect an answer might help us help you. My QT-66 has been tumbling 24/7 for about 6 years and this never happens unless I have some very odd mix of materials, especially if some are below Mohs hardness of 7. This is merely a base that can hold one or two 6lb barrels, or one 12lb barrel. The diameters of the barrels are all the same, thus the speed of the material in, and the amount of impact in the internal cascade face should be the same.
|
|