|
Post by MrMike on Oct 11, 2016 20:40:31 GMT -5
Been experimenting with this, trying to isolate & direct the vibrations to where they need to go. Not finished, trying to come up with a holder & barrel combination that will work. Any ideas are welcome but I don't have any welding equipment. Just for S&Gs I attached a large bottle with bungees. About 6-7 lbs of rocks. Hard to see in the vids but it really rolls the rocks. www.flickr.com/gp/147447506@N05/6f5jt4www.flickr.com/gp/147447506@N05/4H3d1o
|
|
|
Post by MrMike on Oct 11, 2016 20:48:18 GMT -5
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,179
|
Post by jamesp on Oct 11, 2016 21:01:54 GMT -5
Oh yea. Looking good Mike. Keep on posting your progress. Vibrating rocks is witchcraft sometimes. My vibe at it's present settings will not polish Mohs 5 and 6 rocks. Does great with Mohs 7. I think the amplitude plays a big role.
|
|
|
Post by MrMike on Oct 11, 2016 21:10:02 GMT -5
Oh yea. Looking good Mike. Keep on posting your progress. Vibrating rocks is witchcraft sometimes. My vibe at it's present settings will not polish Mohs 5 and 6 rocks. Does great with Mohs 7. I think the amplitude plays a big role. Thanks James.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,179
|
Post by jamesp on Oct 11, 2016 21:15:06 GMT -5
|
|
|
Post by Garage Rocker on Oct 11, 2016 21:20:52 GMT -5
Anxious to see the home build in action. That flourite looks good. You said you didn't get good results on the obsidian though?
|
|
|
Post by MrMike on Oct 11, 2016 22:06:29 GMT -5
Man, your ingenuity floors me. I bet you consider sleep a waste of time. Really appreciate the pics. Lots of good info there. quartz, do you care to share some pics of your vibe?
|
|
quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,341
|
Post by quartz on Oct 12, 2016 0:05:01 GMT -5
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,179
|
Post by jamesp on Oct 12, 2016 4:37:09 GMT -5
Garage Rocker For some reason my Viking vibe did some fluorite well. It has adjustable counterbalances. I tried adjusting them to be more gentle for obsidian and even rhyolite. Added rice hulls and other suggested padding. At gentler speeds it separates padding to left, rocks to right and then that bruises the rocks very slightly all over and not on just the edges. Which prevented a high polish, just a matte finish. But the matte finish is actually micro divots or bruises. Guessing the Lott-O has very short vibrations(amplitude) allowing a mirror polish. If a vibe is traveling back and forth say .01 " at 3000/minute vs .5" at 3000/minute the impacts at .5" will totally damage the surface of the rocks. guaranteed. That's a given. The Vibrasonic base can have 8, 12,14 and 35 pound hoppers bolted to the top of it. Then you adjust the counterbalances for more off-balance for more weight. People have made 60 pound hoppers for the Vibrasonic base and the base has enough power to run that many rocks. My hopper at 14 pounds is running 1.2 out of 5 counter. For 35 pound you adjust to 3 out of 5. The effect of vibe damage looks like: Same rock from afar, matte finish:
|
|
|
Post by MrMike on Oct 12, 2016 7:14:08 GMT -5
Thanks for the video & info. Very cool design, hadn't thought of a PVC hopper.
|
|
|
Post by MrMike on Oct 12, 2016 7:34:34 GMT -5
Garage Rocker For some reason my Viking vibe did some fluorite well. It has adjustable counterbalances. I tried adjusting them to be more gentle for obsidian and even rhyolite. Added rice hulls and other suggested padding. At gentler speeds it separates padding to left, rocks to right and then that bruises the rocks very slightly all over and not on just the edges. Which prevented a high polish, just a matte finish. But the matte finish is actually micro divots or bruises. Guessing the Lott-O has very short vibrations(amplitude) allowing a mirror polish. If a vibe is traveling back and forth say .01 " at 3000/minute vs .5" at 3000/minute the impacts at .5" will totally damage the surface of the rocks. guaranteed. That's a given. The Vibrasonic base can have 8, 12,14 and 35 pound hoppers bolted to the top of it. Then you adjust the counterbalances for more off-balance for more weight. People have made 60 pound hoppers for the Vibrasonic base and the base has enough power to run that many rocks. My hopper at 14 pounds is running 1.2 out of 5 counter. For 35 pound you adjust to 3 out of 5. The effect of vibe damage looks like: Same rock from afar, matte finish: What about adjusting motor speed?
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,179
|
Post by jamesp on Oct 12, 2016 7:53:54 GMT -5
MrMikeI have a fixed speed 1/3 HP on my Viking. Expensive to run. I think speed reducers eat more power, not sure. Most vibes get their impulses from 3600 rpm motors. Maybe 1725's too. Your vibe has a benefit, you can add more bungees and dramatically change the amplitude easily. Springs and bungees looking good. Got me thinking about adding bungees on the home made too. Why didn't I think of that ? genius Vibration a tricky beast. Maybe a video looking down in a Lot-O in operation would be a great way to target your rock movement. I will post a video of my Viking, keep in mind that it is adjusted perfect for Mohs 7 and not Mohs 5/6.
|
|
|
Post by MrMike on Oct 12, 2016 8:00:50 GMT -5
Garage Rocker For some reason my Viking vibe did some fluorite well. It has adjustable counterbalances. I tried adjusting them to be more gentle for obsidian and even rhyolite. Added rice hulls and other suggested padding. At gentler speeds it separates padding to left, rocks to right and then that bruises the rocks very slightly all over and not on just the edges. Which prevented a high polish, just a matte finish. But the matte finish is actually micro divots or bruises. Guessing the Lott-O has very short vibrations(amplitude) allowing a mirror polish. If a vibe is traveling back and forth say .01 " at 3000/minute vs .5" at 3000/minute the impacts at .5" will totally damage the surface of the rocks. guaranteed. That's a given. The Vibrasonic base can have 8, 12,14 and 35 pound hoppers bolted to the top of it. Then you adjust the counterbalances for more off-balance for more weight. People have made 60 pound hoppers for the Vibrasonic base and the base has enough power to run that many rocks. My hopper at 14 pounds is running 1.2 out of 5 counter. For 35 pound you adjust to 3 out of 5. The effect of vibe damage looks like: Same rock from afar, matte finish: What about adjusting motor speed? To answer my own question motor speed controls the frequency (# vibrations) while counter weights adjust the amplitude (size of vibrations). Think you always want high frequency with vibes but adjust the amplitude like jamesp states.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,179
|
Post by jamesp on Oct 12, 2016 8:03:26 GMT -5
I think Larry's vibe is the finest design I have ever seen. Hinged with only 2 springs. Me no expert but it has a concise design that makes most sense. If you put the off-balance shaft on a separate shaft with bigger bearings you can save motor wear. However who knows, the motor may be able to handle an off balance shaft. Someone may steal his design and make a million. Isn't that how it works ?
|
|
|
Post by MrMike on Oct 12, 2016 8:09:30 GMT -5
Agree, Larry's design is ingenious. I'm definitely going to think of ways to move the motor & & attach a shaft under the platform. Thanks again for sharing quartz.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,179
|
Post by jamesp on Oct 12, 2016 8:14:02 GMT -5
Vibration is easily summed up in 4 factors. Damping impulse speed,mass and spring force. Best example on earth is car suspension. You have springs, shock absorbers, mass of car and the shape of the road for impulses. Any 4 can effect amplitude. However natural frequency may be another factor. Some or all ?? systems have a natural frequency. I forgot. "Natural frequency is the frequency at which a system tends to oscillate in the absence of any driving or damping force.[1]" I don't think natural frequency is an issue. Looking at this can't hurt, vibration bloody complicated: en.wikipedia.org/wiki/Vibration
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,179
|
Post by jamesp on Oct 12, 2016 9:01:45 GMT -5
Here is my home made running with a very slow 850 RPM motor temporarily rigged. Looks like a 3600 is going to get the frequency closer to factory type speeds. It's a rattle trap lol.
|
|