jamesp
Cave Dweller
Member since October 2012
Posts: 36,208
|
Post by jamesp on Nov 28, 2017 7:47:50 GMT -5
As I recall, your unit generates the vibrations with an off-center weight. This should generate a sinusoidal wave form. (Provided the hoppers and load don't interfere with the wave form.) Hopefully Probably Maybe Possibly Machines have their own vibration characteristics Bill. Betcha you are correct, straight up sinusoidal. Look at that rig I made. Think adjustment. SLIDE WEIGHTS ---------------------------------------------------------------------------------------------------------------------------------------------- Picture a 1/2 inch steel rod say a foot long welded to the center of the assembly. One on the front. One on the back. Perpendicular to the assembly. With a sliding weight on each rod that can be clamped. To effect the vibration in a serious way without variable speed controls and counterbalance adjustments. Basically a see-saw with big kids or little kids on it. Or a kid sitting closer to the pivot point on each side. No vibe manufacturer would allow such, probably considered dangerous. No threat of burning the motor up because the hopper is isolated by springs. Guitar strings with hand slide, same thing.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,208
|
Post by jamesp on Nov 28, 2017 8:01:53 GMT -5
Yep, that catfish has fooled the best of them. Friend gave it to me. It was her idea to hang it on that beam. Never knew who many people it would fool. I believe it was intended to be a full length pillow for people to sleep with. Ever snuggled up with a catfish ?I am not going to answer that on the grounds it might incriminate me! By the way the Vibraminisonic works awesome! If you get inspired to make a vibe using those hoppers let me know. Got pipe, will ship. Had a half a dozen 20' sticks of it.
|
|
|
Post by TheRock on Nov 28, 2017 12:41:11 GMT -5
jamesp JP I would need the base vibration unit and I don't know where to get one cheap enough to make the project worth my time.
|
|
|
Post by TheRock on Nov 28, 2017 14:07:33 GMT -5
jamesp JP I would need the base vibration unit and I don't know where to get one cheap enough to make the project worth my time. The shop you are building give credit to the value of your time. WHEN you finish your shop I hope you will consider such projects. Pulled rocks from Vibraminisonic after 20 hours. So far so good. Ahead of schedule. Means nothing. final polish quality is the target. Keep an eye on Ebay, I bought mine from an unknowing southerner cheap. Grandad's machine, they had no idea what it was worth. I hope over time I can contribute and give back something to the hobby and come up with something that others may enjoy.
|
|
|
Post by TheRock on Nov 28, 2017 14:44:44 GMT -5
jamesp If it does happen don't expect me to come up with Formulas, Equations, and Theory's like Einsteins fear of RELATIVES
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,208
|
Post by jamesp on Nov 28, 2017 14:49:29 GMT -5
jamesp If it does happen don't expect me to come up with Formulas, Equations, and Theory's like Einsteins fear of RELATIVES Stay away from the RELATIVES. Life easier that way.
|
|
|
Post by MrP on Nov 28, 2017 15:29:59 GMT -5
jamesp JP I would need the base vibration unit and I don't know where to get one cheap enough to make the project worth my time. The shop you are building give credit to the value of your time. WHEN you finish your shop I hope you will consider such projects. Pulled rocks from Vibraminisonic after 20 hours. So far so good. Ahead of schedule. Means nothing. final polish quality is the target. Keep an eye on Ebay, I bought mine from an unknowing southerner cheap. Grandad's machine, they had no idea what it was worth. jamesp And you almost had to be forced into buying it!.................................MrP
|
|
|
Post by grumpybill on Nov 28, 2017 17:08:48 GMT -5
Not sure, but it may be possible to hit harmonics by adding weights to a hopper. Effectively cutting vibration from 3400 to 1700(1/2) or 1133.3(1/3) or 850(1/4). Like skipping a heart beat. I doubt it. You want to lower the frequency, correct? Harmonics/overtones are higher frequencies. If the frequency could be changed by adding/removing weight to the hopper assembly, the frequency would change with the weight of the load, wouldn't it?
|
|
|
Post by MrP on Nov 28, 2017 18:05:39 GMT -5
jamesp And you almost had to be forced into buying it!.................................MrP That Vibrasonic back then ? Yes Nov 2014 ................................MrP
|
|
|
Post by MrP on Nov 28, 2017 18:22:48 GMT -5
You have had that toy a long time..................................MrP
|
|
|
Post by HankRocks on Nov 28, 2017 20:22:00 GMT -5
I would agree with Bill, adding weight should not change the frequency. It should change the intensity, more weight will decrease the intensity. If the springs do not keep up you will move into an un-balanced state, you know the old ".... cats and dogs living together" If this discussion moves into the realm of Quantum Physics, I am going for a beer!!
|
|
|
Post by MrP on Nov 29, 2017 6:19:54 GMT -5
I would agree with Bill, adding weight should not change the frequency. It should change the intensity, more weight will decrease the intensity. If the springs do not keep up you will move into an un-balanced state, you know the old ".... cats and dogs living together" If this discussion moves into the realm of Quantum Physics, I am going for a beer!! The counterbalance can be set from a minimum of 0.1 to a maximum of 1.6 for 14 pounds of rock. Settings above 1.6 for 14 pounds can damage the machine. A gentle setting of 1.1 works great for agate. My intention is a milder setting below .7. Below .7 you see a big slow down. Playing the devil's advocate, if you reduce the counterbalance enough something has to give. Certainly the amplitude, eventually the frequency. -------------------------------------------------------------------------- Sure does appear that settings at .7 or below no longer activate the springs at 3400 vibes per minute. There is not enough counterbalance force to vibrate the 14 pounds at such a speed. Guessing some division of 3400 unless it is unstable vibration. If it is unstable it is a gentle unstable. Gentle instability probably not a problem for tumbling I believe the term that describes this situation is approaching mechanical hysteresis, reduce forces yet further and the lag turns into a slow down. hysteresis 1. the lag in response exhibited by a body in reacting to changes in the forces, especially magnetic forces, affecting it. ------------------ The problem with running the long 13 inch hopper at .7 was separation. All the big rocks separated to one side, the little rocks and media went to the other side. Rock damage occurred. Even the slurry went to one side. Now there are 4 inch wide hoppers. Separation issue greatly reduced.
----------------- The weights I intend to add are small for fine tuning the action. Slide weights on each side of hopper and balanced(or off-balance if it helps action). Instead of making fine adjustments to the counterweights which is a pain. ****Danger - Turn of vibe before approaching. jamesp I finally got my Rockette 800 running. I cannot find liners for the tub that came with it so I made a liner out of roofing material. It did come with a liner but what do I do once it is shot so I had to come up with something. I also made a new tub out of 8" plastic pipe, that is used for underground utilities. The pipe is 9" long with a 6.75 inside diameter. I am running a load of 1-2"+ stones. I threw in a chunk of pet wood that is 5X3X2 and it runs dead center all the time. All rocks seem to run mixed with no separation by size. I like the fact that the tub hangs better then setting on top. The motor is only 1725 RPM and spins the counterweight shaft at 3000 RPM. A new double ended shaft motor for this one is a lot cheaper then the 3600 RPM one. Neither of the Vibe tumblers are quiet but with the new plastic tub on the Rockette it is loud. When I started it with just rocks in it the sound was unbelievable. It was better once a slurry started but still loud.............................MrP
|
|
|
Post by MrP on Nov 29, 2017 10:24:15 GMT -5
jamesp I think the 800 is .8 cubic foot. The counterweights adjust the same as the Vibrasonic. Ther is no reason for you to not make one of these for yourself. Just make a frame to hang it on with stiff springs.
|
|
|
Post by 1dave on Nov 29, 2017 11:33:02 GMT -5
jamesp I think the 800 is .8 cubic foot. The counterweights adjust the same as the Vibrasonic. Ther is no reason for you to not make one of these for yourself. Just make a frame to hang it on with stiff springs. Photo?
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,208
|
Post by jamesp on Nov 29, 2017 11:37:26 GMT -5
jamesp I think the 800 is .8 cubic foot. The counterweights adjust the same as the Vibrasonic. Ther is no reason for you to not make one of these for yourself. Just make a frame to hang it on with stiff springs. Photo? Waiting anxiously
|
|
|
Post by 1dave on Nov 29, 2017 11:50:29 GMT -5
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,208
|
Post by jamesp on Nov 29, 2017 13:31:37 GMT -5
|
|
|
Post by MrP on Nov 29, 2017 13:39:03 GMT -5
jamesp I think the 800 is .8 cubic foot. The counterweights adjust the same as the Vibrasonic. Ther is no reason for you to not make one of these for yourself. Just make a frame to hang it on with stiff springs. It would be a marvel to own an original. I lack confidence in making a vibe. It is sure on my bucket list. Messing with the Vibrasonic and learning the best vibration scheme for the time being. That hanging design makes a whole bunch more sense. Could not care less if it makes the machine large. No concern there. Like that Rockette. Did you repaint that one or is that the original paint ? The picture is one I found on the Internet while I was researching my machine. Mine doesn't look that good but is not too bad. I have tried searching a number of times and can't find any info, other then the patent, on this unit. I would like to find a source for the rubber liners but no luck...........MrP
ETA I had a photo of mine but PB ate it. The only place I posted was RTH so of course all photos are gone.
|
|
|
Post by HankRocks on Nov 29, 2017 15:52:26 GMT -5
about 2 weeks ago I picked up the Rockette 800 I referenced earlier and looks identical to the one in your picture. My guess on capacity is somewhere betweena 15 and a 20 pound load. Need to pick up some rubber shoes for the legs, probably the chair leg slip-ons. The cushion material between the hopper and the hopper frame looks old and may need to be replaced. It has a liner so just need to get some rocks ready to test with. It's a heavy son of a gun. I saw the counterweight on the shaft, not sure how to adjust. Suppose trial and error will do.
|
|
|
Post by MrP on Nov 29, 2017 16:28:36 GMT -5
about 2 weeks ago I picked up the Rockette 800 I referenced earlier and looks identical to the one in your picture. My guess on capacity is somewhere betweena 15 and a 20 pound load. Need to pick up some rubber shoes for the legs, probably the chair leg slip-ons. The cushion material between the hopper and the hopper frame looks old and may need to be replaced. It has a liner so just need to get some rocks ready to test with. It's a heavy son of a gun. I saw the counterweight on the shaft, not sure how to adjust. Suppose trial and error will do. HankRocks Just a warning: don't put any rocks with a sharp edge in it with the liner you have. I tumble slabs right off of the saw with all of my tumblers so I made a new liner out of rubber roofing. I ran tumbled rocks in it just to see what it would do and it did a great job. The next run I used all smalls and threw in a couple of 7" Brazilian Agate slabs. Sometime in the run the slab caught the liner and tore it. Sure was glad I had the one made in at that time. The roofing liner does work because have used one after that and it did fine. Wish I could find a place to get original liners some place..................................MrP
|
|