quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
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Post by quartz on Feb 24, 2016 0:02:26 GMT -5
www.flickr.com/photos/100577034@N04/shares/p4s425 I built this thing just to see if I could do it and make it work. I purposely used materials at hand, saved from the scrap guy and burn pile with no "rocket science" involved. Motor is 1/8 HP and overdriven to turn the shaft 2870 RPM per photo-eye tach. I can adjust the amplitude of vibration by turning wing nuts under the rubber bushings on the frame pivot end and at the outer end of the frame. The springs are a matched pair, surplus from a previous project, used them because they looked about right. The kickup on the frame over the springs is there because that is the way the pieces were made, necessary for proper function ?. I'll keep tinkering with this as a test bed for building a larger one able to run rocks up to about a pound. Overall, a fun project, and it works. Shows average folks can build one, no engineering necessary. With a rubber cap on the fill hole it runs quieter than our Viking tumbler. Flickr says videos can now be downloaded directly, but haven't figured that out yet.
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Intheswamp
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Member since September 2015
Posts: 1,910
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Post by Intheswamp on Feb 24, 2016 7:36:35 GMT -5
Nice job, Larry!!! A very creative use of "found" items. Seems like good action,too!
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Post by captbob on Feb 24, 2016 9:41:52 GMT -5
This is fantastic! Very impressive build and many thumbs up!! How do you remove the barrel? jamesp
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Fossilman
Cave Dweller
Member since January 2009
Posts: 20,681
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Post by Fossilman on Feb 24, 2016 10:14:16 GMT -5
Hey Larry,great idea!!! Let us know the results of the tumbles too (from the machine)...
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jamesp
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Member since October 2012
Posts: 36,155
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Post by jamesp on Feb 24, 2016 10:54:38 GMT -5
Larry is the man. If it can be done he is the capable one.
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Post by toiv0 on Feb 24, 2016 20:01:23 GMT -5
Nice job looks like it runs sweet and has good action
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Post by Drummond Island Rocks on Feb 24, 2016 20:40:24 GMT -5
Neat project. Anxious to see your results with that one. Action looks pretty good already.
Chuck
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quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
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Post by quartz on Feb 25, 2016 0:01:52 GMT -5
captbob, I run a socket up through holes in the table and loosen the nuts that hold the eye bolts on the frame. That loosens the plumbers tape and the barrel comes right off. Thanks to all for the comments. I ran it ~10 hrs. today, 220 grit definitely improving the finish on the already roughed rocks.
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jamesp
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Member since October 2012
Posts: 36,155
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Post by jamesp on Feb 25, 2016 9:28:15 GMT -5
Only 2 springs and a pivot point may be a the future of vibes.
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Post by oregon on Mar 8, 2016 13:35:46 GMT -5
Nice job... Does anyone remember what RPMs the Lot-O motors run at?
I'm also curious why you chose pairs of offset weights on the shafts instead of a single weight like the lotto does. Maybe a single one of those produced too much vibration? If the 4 counter weights are all equivalent seems like it should almost be balanced. I like it. Maybe like the lotto, you could just make a snug barrel holder so it's simple to remove & clean out. Looking forward to the results.
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quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
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Post by quartz on Mar 8, 2016 14:31:50 GMT -5
Time for an update to anyone interested. I ran 34 hr. in 220, 42hr. in AO of unknown grade [moving sale purchase a couple years ago] that works well as pre-polish, and 31 hr. in cerium oxide. The machine seems to do its work with about 30hr. per cycle runs. I put in 2-14 oz. pkgs. of 1/2" decorative glass beads from Dollar Tree as a cushioning just to see how it would work. Thanks to jamesp for that idea. Used 2tbs. 220, made good slurry, 2tbs. AO, proved to be too much, and 1tbs. CO, plenty. Tried a soap run w/2tbs. of dry laundry soap and minimum water and that stopped everything; thinking the grittiness of the soap made too much traction between load and barrel walls. Ran a couple hrs. in a squirt of Dawn to make sure things were clean. I have 4lb. 10oz. finished rock and 24.4 oz. glass which is about right for a barrel measuring just over 1/2 gallon [~ normal 6lb. barrel], didn't weigh before loading. After solving numerous rattles and learning tuning of the machine, we have some nicely polished rocks and glass, but not the final "pop" of polish that make them really nice. I ran the glass through every cycle to watch it, and it came back from 220 quite well, easy to read through. My wife and I agree, we have the smoothest-feeling rocks we have yet done, even over those with a better polish. Now to find that final bit of really good polish. I'm confident enough in the design that I'm starting the hunt for parts not on hand to build a machine of 3 1/2 gallon capacity. It's being a good project and learning curve, keeps me out of trouble.
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quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
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Post by quartz on Mar 8, 2016 15:04:01 GMT -5
oregon: You wrote while I was writing this and answering a couple phone calls. The reason for the outside weights is to provide ease of change in case the initial design idea was in need of big change to make it work, wouldn't have to take so much apart. Granted, not safest around little kids or pets, have neither. This barrel is easy to remove by loosening the nuts holding the eye bolts that hold the plumbers tape on the pivot end. There's a hole in the table to stick a socket up through. Design "B" will have a more substantial saddle and easier barrel clamping. The whole idea here was to make something out of pretty much nothing just to see if it would work at all, lots of thought but no rocket science or real "engineering". Thanks for the compliment.
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jamesp
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Post by jamesp on Mar 8, 2016 22:27:02 GMT -5
Looking forward to this one quartz. Another video would be the picture that is better than a thousand words. It is an accomplishment to pull off a home made vibe. Hat's off.
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quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
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Post by quartz on Apr 9, 2016 23:47:20 GMT -5
Another update: I rebuilt the frame to a more suitable design, and moved the motor up instead of underneath in an effort to better control belt flop, and it worked. Also came up with a pulley to increase the shaft speed to 3000 R.P.M. I immediately found the shaft weights were too heavy, so I made some of 1 1/4" diameter stock, worked much better. In trying to improve the polish I ran a run of .5 micron alumina, dulled the polish in 6 hrs. Fiddled with a variety of modifications, tried cerium oxide and tin oxide with up to a cup of sugar; unsuccessful. My wife suggested corn starch so I mixed a half cup to a slurry and ran it with 1 tbs. of tin oxide mixed in. Had to add a bit of water several times the first day to keep a nice thick slurry, and this is what I got. The glass beads I ran with the rocks didn't polish very well, but that was expected. www.flickr.com/photos/100577034@N04/26312833936/in/dateposted-public/ Ran it 28 hrs. and got what I wanted, a really good polish. Being this is entirely a trial machine, I threw in a little of everything to see how it would work, some not the best material, happy with result. One downside, it is now fairly noisy, had to move it out near the shed.
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jamesp
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Post by jamesp on Apr 10, 2016 7:38:07 GMT -5
This is a big accomplishment. Polish looks grand. So the belt is driving like 90 degrees to the spring centerlines ? As opposed to the Viking belts being in-line with the spring centerlines ?
The o-ring belts on the Viking actually holds the top platform down on the springs, so the springs are also the belt tensioners. And there are all kinds of o-rings being used for belts on the Viking, certainly some stiffer than others. Could effect the way it vibrates.
Fine work Larry.
Opened the video. Really really like your PVC hopper. That makes sense, inexpensive and darn easy to build. I cannot get it to run for some reason so I am trying to load it to my Vimeo account. Gotta see her run. Yes, belt at 90 degrees. Excellent idea.
Probably should have a patent. Bet you this one will get duplicated. The pivot arm with 2 springs should be an industry standard-not kidding. Makes so much more sense than having the whole weight of the hopper sitting on springs at all 4 corners. Belt flop totally isolated from vibe direction. Seen a lot of fine machine designs over the years, this one may top the list for being concise, simple and reliable to perform a relatively complicated operation.
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jamesp
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Post by jamesp on Apr 10, 2016 8:21:44 GMT -5
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victor1941
fully equipped rock polisher
Member since November 2011
Posts: 1,978
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Post by victor1941 on Apr 10, 2016 10:38:38 GMT -5
The final design is really sweet. I think an average person with good shop/tools skills should be able to make the last design. Thanks for showing your steps in design.
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quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
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Post by quartz on Apr 10, 2016 11:00:20 GMT -5
Thanks for the +'s. victor1941, this isn't the "final design", it's a stage in evolution of what I hope to accomplish. I want to be able to get a polish on pieces upward of a pound, dislike being stuck doing smaller pieces. The base is quite crude, but allows for ease of modification as a test of ideas. I have to credit my wife for the corn starch idea, it takes a good cook to make shiny rocks I guess. I do hope many will jump on a project like this, it would likely help development greatly by being able to exchange ideas .
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Deleted
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Post by Deleted on Apr 10, 2016 18:56:44 GMT -5
How is the pivot end (end opposite the springs) secured to the deck?
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quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
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Post by quartz on Apr 10, 2016 19:27:40 GMT -5
@shotgunner, 1/4" bolt thru frame, 3/4 dia.x1 1/4 rubber [was solid, I drilled it], and thru base. I have wing nuts on the bolts and under the base, can tune vibration a little with them.
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