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Post by pauls on Feb 15, 2023 17:58:15 GMT -5
Duplicate post removed. Paul.
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Post by pauls on Feb 15, 2023 17:36:18 GMT -5
For the people thinking about doing a heart and thinking it's too hard, have a look at the first two photos of the rough and the rough shape and you can see how to get a nice even heart. Centre your pattern, that's the silver line in the first photo, cut or grind straight across the top at right angles to that line. then shape the sides so they are nice and even, start shaping the cab as in the second photo, at this stage you are just making a shield shape. Get a nice even shield shaped cabochon, sand the shield with the first sanding grit to even out any lumpy bits. Now you have a good shield cabochon that with a little bit of extra sanding could be finished. Then you grind the cleavage and the lobes, you need to keep the imaginary centre line of the shield in line with the edge of your wheel when grinding the cleave across the face. Then go back and rough sand the lobes and cleavage. This is the trick, do not consider making it into a heart until your shield is a nice and even cabochon.
Good luck people, give it a go, by breaking the operation down into these steps you can do it.
Apologies for the last photo being posted twice, no idea how that happened, dust from the tissue as well. Sigh.
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Post by pauls on Feb 15, 2023 1:54:09 GMT -5
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Post by pauls on Jan 29, 2023 20:36:57 GMT -5
Flip your blade, if it's dished it will start to cut the opposite way. It's a good idea to flip your blade regularly to stop it dishing anyway.
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Post by pauls on Jan 23, 2023 18:58:34 GMT -5
I have never covered the rollers, As long as both rollers are driven then I can't see the need.
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Post by pauls on Jan 11, 2023 16:41:37 GMT -5
Vibes are a bit more complex machines and are a little bit more expensive, barrels are quite expensive to replace, that is a good reason why rough grinding is done in a rotary, if it grinds rocks it grinds barrels.
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Post by pauls on Jan 11, 2023 16:34:15 GMT -5
14 pillow block bearings, I think I would beef up the rollers to 3/4 inch and lose a few bearings. I have never found the need for sleeves on the rollers. Only one driven roller sleeves might be necessary, but both rollers driven, not necessary. If it was my build it would be all steel but that's just me, Apart from that it looks good.
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Post by pauls on Jan 8, 2023 22:51:53 GMT -5
If you know someone with a 3D printer they are a reasonably easy print, finding my way through the CAD software was a steep learning curve though.
Failing that, grab your index and take it to a good machine shop. Get them to churn out all possible permutations of that size spur gear, 40, 60, 72, 80, 84, 96, 120. and probably a few other odd bods of index teeth. I almost exclusively use 96, occasionally 72, 84 and 120
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Post by pauls on Dec 20, 2022 18:16:23 GMT -5
Careful using transformer oil, It used to contain PCBs (I think) anyway carcinogenic whatever it was. I use mineral oil, I find where I am generic brand baby oil is cheaper than horse laxative. My rocks come out smelling of roses too. I filter it with a bit of flannelette shirt , though a pillowslip works just as well.
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Post by pauls on Dec 2, 2022 21:50:36 GMT -5
I remember seeing this in an ancient Lapidary book, not sure which book though, it was half a century ago. Apparently the setup consisted of two large diameter plates with a matching groove in each plate, one rotated, the other was stationary. The idea was that this would produce eggs because of the different radius at either end of the rock in the groove. I never tried it and I don't know anyone that has, bead machines were a similar setup and I was dubious that you would actually get an egg.
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Post by pauls on Nov 28, 2022 1:55:26 GMT -5
No, polish should be just the rock, you start with coarse grit which leaves deep dings and scratches, which diffuse the light so your rock looks cloudy, gradually getting finer and finer until the surface imperfections become too small to diffuse the light and it looks polished. There was a theory put about by a bloke called Beilby who reckoned that polishing caused the surface atoms to migrate and create an absolutely smooth surface, people are still arguing over if that is an actual thing or not. Look up Beilby flow.
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Post by pauls on Nov 23, 2022 21:24:18 GMT -5
I agree about the gloves, wow that thing hurts when that water hits your skin. Wear glasses too, bits of grit and dirt and chips fly off with tremendous force.
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Post by pauls on Nov 22, 2022 16:35:24 GMT -5
I have been washing my tumbling sludge in the same patch of lawn for years, If anything it seems to grow better than the rest of the grass. If you are concerned just put it in a bucket and let it dry out then dump it in the bin.
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Post by pauls on Oct 13, 2022 19:43:56 GMT -5
My observations in no particular order
I have a part of a geode that it is obvious the Agate was soft (a jell) when it formed, it is nicely banded but you can see where the Agate has become detached from the top of the gas bubble and has slumped down.
It is reasonably common in the Agates I collect from Agate Creek Queensland to find pseudomorphs of dogtooth Calcite in the geodes, not uncommon to find Aragonite /Agate pseudomorphs as well. I have a really nice smokey Quartz stalactite that has obviously formed around a Calcite stalactite that has been completely dissolved but Calcite crystal surfaces are still visible as hollows inside the smokey stalactite.
Colour doesn't appear to always be part of the silica jell as it is laid down in bands, colour seems to arrive later, You find blobs of colour in areas of geodes regardless of what the banding is doing.
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Post by pauls on Oct 4, 2022 18:19:00 GMT -5
Moonstone is Feldspar and thus has very strong cleavage planes, meaning that whatever you do to it , it wants to split along those planes. Even worse is the fact that the reason Moonstone is actually a thing is that it is a mixture of different Feldspars in layers so it wants to split along those different types of Feldspar as well. I have tumbled it successfully and surprisingly (to me) it went pretty well, All I was hoping for was to clean the stones up, and maybe get a bit of a polish so I could see inside them to pick out stones for cabbing and faceting, for a bunch of cracked and falling apart rough I ended up with some nice stones.
I used a lot of smalls to cushion everything and filled the tumbler (vibe) right up, The smalls I used were lots of rabbit poo sized round (dodecahedron) crystals of Garnet. I usually don't let anything with a crack past first stage but this was just a clean up job so I ignored it, gave it minimum time in each stage and it worked. I think the takeaway here is to use lots of cushioning media and it will work.
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Post by pauls on Sept 26, 2022 1:32:27 GMT -5
Me me me, pick me. I have Dave. The old "Red Rattler trains in Melbourne were painted with paint made from Jarosite, it was mined near a beach I liked surfing off. Vivianite was also found not far away. www.pinterest.com.au/pin/408490628674746047/Now you know a bit of Melbourne History
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Post by pauls on Aug 23, 2022 18:31:25 GMT -5
Just for your information, when you get your new grit kit from the Rockshed you probably don't need to go right back to first stage, take your rocks back to about third stage and go from there.
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Post by pauls on Aug 23, 2022 18:25:46 GMT -5
People are tippy toeing around the issue here, Please take a couple more photos that are well lit, in focus and the rock is dry, from your photo it is just too blurry to see.
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Post by pauls on Aug 10, 2022 22:13:54 GMT -5
Believe it or not Google is your friend. I looked it up. Kidney stones are a mix of a heap of different minerals ranging from hardness 1 to hardness 2.4 so all in all very soft stuff, it would be a pain in the kidneys (close anyway) to work.
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Post by pauls on Aug 9, 2022 18:50:54 GMT -5
I have a couple of them, fantastic machines. The barrels do wear out. Mind you mine have been in use for years. When they get real thin they go on to polish duty and don't seem to wear any more. (Or at least that slowly it's not noticeable.) The double spring (one spring pushing one pulling) also breaks, There is no cheap over the counter fix for it either. They do sell a complete refurbishment kit with grommets springs etc. everything you would need to get it back to new condition.
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