jamesp
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Post by jamesp on Sept 30, 2014 10:40:50 GMT -5
Here is an 18 inch lap that did well at getting saw marks out of larger specimens. only used it for 100 and 220 grit. An adhesive backed 18 inch diameter 100 grit sand paper pad was stuck to the bottom of the drum. Drip from above and lard added to keep powdered grit in place. Drum spins at 120 RPM until motor burned up. Motor and spur gear box purchased from scrap yard. However, replacement cost of motor was very expensive, so machine was retired.
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Post by mohs on Sept 30, 2014 11:55:05 GMT -5
excellent descriptions & mechanical know how ingenuity ect... jamesp The lapping plate is made from what?
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Post by captbob on Sept 30, 2014 12:03:44 GMT -5
James - somehow, you bring this to mind.
I like the way you think and pretty sure you'd make a damn fine neighbor.
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jamesp
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Post by jamesp on Sept 30, 2014 14:04:19 GMT -5
I'd love to be your neighbor too captbob, are you sure you want a neighbor that's a tad on the....trashy side ??
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jamesp
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Posts: 36,158
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Post by jamesp on Sept 30, 2014 14:06:27 GMT -5
excellent descriptions & mechanical know how ingenuity ect... jamesp The lapping plate is made from what? The bowl support is polycarbonate Ed. The aluminum bowl is probably a 30 gallon aluminum cooking pot that has been sawed of short.
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Post by mohs on Sept 30, 2014 14:41:59 GMT -5
what type of material am I seeing through on the sprocketed circular plate that is attached to the motor spindle?
it seems that can see through that to the wall siding on the other side
or is it a reflection ?
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Deleted
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Post by Deleted on Sept 30, 2014 17:04:04 GMT -5
Only Jim would think of using lard as a cutting grease. I bet it works best on warm but not cold nor hot days. Running low? Go shoot a pig, make Canadian bacon, pork ribs, a coupla' hams and render the bacon for more lube. Food and fun; all in one bullet. I wonder what he does with the snouts. Freaking Genius
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Post by mohs on Sept 30, 2014 17:58:16 GMT -5
well diamonds are hydrophobic so it does act as adherent I'm all for a pork roast mostly
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jamesp
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Post by jamesp on Sept 30, 2014 18:57:05 GMT -5
Only Jim would think of using lard as a cutting grease. I bet it works best on warm but not cold nor hot days. Running low? Go shoot a pig, make Canadian bacon, pork ribs, a coupla' hams and render the bacon for more lube. Food and fun; all in one bullet. I wonder what he does with the snouts. Freaking GeniusCan't take credit for the lard idea Scott, the grit salesman was laughing when he told me the US military uses lard on their fancy SiC lapping operations. That guy is a wealth of information. He lives in Alabama and I met him over the phone when searching for grit. He is the SE US sales rep for the monster abrasive company Washington Mills. They make about all abrasives we use. I just happens to live close to I-20 and he used to stop by here on his sales route. To goof off. I could not buy thru him but he traded 5 pound samples of all kinds of crazy abrasives for rocks for his son and MIL to tumble. Or gave me messed up batches. Dixie Crystals, corn oil and lard-the south will rise again !! Interesting using organic compounds for lubricants.
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jamesp
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Post by jamesp on Sept 30, 2014 19:04:50 GMT -5
what type of material am I seeing through on the sprocketed circular plate that is attached to the motor spindle? it seems that can see through that to the wall siding on the other side or is it a reflection ? it is a clear piece of polycarbonate bolted to the sprocket that was on the motor/gearbox combo Ed. It has holes drilled in it to receive the aluminum bowl. I just bolted the clear plastic disc to the sprocket since the sprocket is dead flat. Here is a better view:
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Deleted
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Post by Deleted on Sept 30, 2014 20:22:30 GMT -5
so in this case the grit was PSA sand paper lubricated by lard?
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Post by mohs on Sept 30, 2014 20:46:38 GMT -5
so the abrasive paper is adhered to the inside of the tub bottom as the wrought iron soul holds down the slab w/ lard dripping on the grit with the outcome being that the lapping is occurring inside that tub ? This is revolutionary!!! I’ll pitch in for a motor and a hog to pit q
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jamesp
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Member since October 2012
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Post by jamesp on Sept 30, 2014 22:17:41 GMT -5
so in this case the grit was PSA sand paper lubricated by lard? Sand paper starts w/100 grit. But wears. And then just served as a carrier for any SiC grit. till it was worn out. Sandpaper had a cloth backing, then adhesive. The most insane lapper I ever saw was a 24 inch floor buff pad spinning at fast motor RPM 1725. Had a metal ring around it about 24.5 inches standing an inch around the edge of the pad. Then 3 or 4 pie rings or cut off rings of 6 " PVC pipe with slabs in them and plaster of paris poured over them. Wet the pad, and sprinkle 'some sized' SiC grit on it.(can not remember the grit size) Start the motor and put the 4 rings with slabs poured in them on the buffing pad slab side down. the 4 rings would spin around in 24 inch circles while rotating them selves like a planetary gear system. Malachite with a wet shine. About any soft stone would polish on it. As it ended up polishing on its own dust. It was left running for about 12 hours. It was a dusty operation. But the highest polish I have ever seen.
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jamesp
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Post by jamesp on Sept 30, 2014 22:38:47 GMT -5
so the abrasive paper is adhered to the inside of the tub bottom as the wrought iron soul holds down the slab w/ lard dripping on the grit with the outcome being that the lapping is occurring inside that tub ? This is revolutionary!!! I’ll pitch in for a motor and a hog to pit q Yes, like so Ed. It could have run faster than 120 RPM. The gearbox is an expensive spur gear box like a 4 speed in a car. I am suspicious that the motor was not designed to run vertical. Another reason I did not replace it. But a v-belt w/sheaves could have been rigged to run it w/out that fancy gear reduction spur gear box. It would handle fairly large specimen rocks, not just slabs. Better if the rocks rotated in the holder to mix up the grind.
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Post by captbob on Sept 30, 2014 23:15:09 GMT -5
On the bright side, you'd never have to worry about any of them al-Qaeda types sneaking in and stealing yer slabs!
James, did you see the agatized stuff I posted in specimens?
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jamesp
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Post by jamesp on Oct 1, 2014 5:30:06 GMT -5
On the bright side, you'd never have to worry about any of them al-Qaeda types sneaking in and stealing yer slabs! James, did you see the agatized stuff I posted in specimens? Nice specimens captbob. Big ones at that. Do you display them ?
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Deleted
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Post by Deleted on Oct 1, 2014 10:18:38 GMT -5
why are you posting at 4am?
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jamesp
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Post by jamesp on Oct 1, 2014 11:28:20 GMT -5
Achy body. Always get up after 5 hours. Often take a nap in the heat of the day.
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FLrockhound
spending too much on rocks
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Post by FLrockhound on Oct 1, 2014 13:52:30 GMT -5
This is a really interesting price of machinery. If it gets the job done an done well, can't really complain. I love southern ingenuity.
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jamesp
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Post by jamesp on Oct 1, 2014 14:07:20 GMT -5
This is a really interesting price of machinery. If it gets the job done an done well, can't really complain. I love southern ingenuity. we are smarter than we look fl.
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