muleshoejoe
off to a rocking start
Member since July 2008
Posts: 16
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Post by muleshoejoe on Jul 3, 2010 18:18:24 GMT -5
For all you with flat lap experience I was wondering if you were to purchase a flat lap would it be a vibrating lap or rotary one? I am looking to get one but would like some input. Thanks, MSJ
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Post by Roller on Jul 3, 2010 21:39:44 GMT -5
I think the vibrating laps are made for mostly geodes .A rotary can do many things including geodes ... I dont know much about the vibrating laps but I would imagine you just put a geode there and let it go for awhile until its polished ..The rotary flat lap can do all kinds of neat cabs though ... I am sure someone else will jump in and explain more !!!
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Post by jakesrocks on Jul 3, 2010 22:03:06 GMT -5
You can do any flat surface on a vibro lap. Heavy nodule halves can be loaded on as is, but for lighter slabs and small nodules you'll have to dop a weight on them to keep them from bouncing around, It's also a good idea to use rubber bumper rings around the outside of each piece. These can be cut from various sizes of old inner tubes. I have a 20" Highland Park vibrator, and love it. With a rotary lap, you almost have to stand there and hold each piece on the lap plate. It can take hours to properly lap a piece. With the vibrator, you just load your pieces and grit, start a slow water drip on it, and walk away and leave it. Don
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Post by rockmanken on Jul 3, 2010 23:28:22 GMT -5
The best way to answer this question is: what are you going to use it for? I have both a vibrating lap for larger FLAT slabs and rocks and geodes and an Ameritool flat lap for cutting cabachons and polishing them. Also can do smaller geodes on it. Ken
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Post by johnjsgems on Jul 4, 2010 8:34:01 GMT -5
Ken is right, more information needed. The old style rotating steel plate, hands on flat laps you used with grit were much faster but labor intensive. The few companies still making them are charging quite a bit but used ones can be found really cheap sometimes. I've used those at a club work shop and preferred them over the vibrating lap. The only vibrating lap I had was a Lortone and I had mixed and sometimes not great results. I prefer my Barranca wet polisher to either. Really hands on but fast. I just refinished some granite counter tops with it and thought biggest slabs I've ever polished (largest was 7' x 25"). I have a whole new respect for counter guys now. And,like Ken said if you want to do small slabs and cabs the Ameritool or High Tech Diamond would be the way to go.
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muleshoejoe
off to a rocking start
Member since July 2008
Posts: 16
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Post by muleshoejoe on Jul 4, 2010 9:14:33 GMT -5
Thanks for the replies so far. Good info. I don't think I will be doing slabs with it so much. I put most of my smaller slabs in the vibrating tumbler and get good results with that. Big slabs I would want to put on the lap. The biggest reason I want a lap is I have some bigger pet wood and agate halves that I want to polish as specimen ends. I was wondering with a rotary lap if you apply the pressure, or does the rock weight create the pressure?
Also with the rotary, how long are we talking between grit changes? Assuming the rock has a very little saw marks?
John, I like the idea of the wet grinder! But I have heard they burn up, short out , etc. so have steered clear of them. But I do llike the idea of them. I looked at Makita and Barranca both, even the cheap Ebay ones. Lol. Will the coarser grit pads remove saw marks quickly of do you go through a buch of pads and elbow grease?
Thanks MSJ
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joemojave
starting to spend too much on rocks
Member since October 2009
Posts: 133
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Post by joemojave on Jul 4, 2010 15:31:31 GMT -5
If I where you I would get a rotary one. A flat lap can do everything a grinder can do more easily and it can do flats. You can get laps up to 80 grit diamond laps or so from facet suppliers, or you can make your own bonded diamond laps with epoxy as some on this forum have done with wheels. You can also make your own soft laps with 3m sanding sponges that will get the faces out of your cabs in no time flat. You can also put a saw blade on there and use it as a trim saw if you dont have one.
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Post by jakesrocks on Jul 4, 2010 15:48:54 GMT -5
Both types of laps have their uses. I have an Inland flat lap for small stuff. Also the magnetic disks for my Genie. But for larger material I'd go with the vibrating lap. It takes longer, but is much less work for the person doing the lapping. The time spent holding a large piece on a rotating lap can better be used cabbing or cutting rocks. Just check the vibrating lap every hour or so to see the progress, and check that it has enough water. Don
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Post by rockmanken on Jul 4, 2010 17:10:45 GMT -5
Let me clear the mud, AGAIN. There are 2 (TWO) types of flat laps. Vibrating and rotary. Vibrating laps come from 12" and up with the most common being 15', 18" and 24". You add grit and water to make slurry and most of the time you add weight on top of what you are face polishing (geode, slab, block of rock, etc.) A rotary flat lap has a flat wheel that turns that is a specific grit and you change the wheel whenever you want to change grits. From your answer, you want a VIBRATING flat lap, not a rotary. Hope this is as clear as mud. Ken
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snuffy
Cave Dweller
Member since May 2009
Posts: 4,319
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Post by snuffy on Jul 4, 2010 17:22:33 GMT -5
I'm with Ken. I have a 20 in lortone and it does the job.
snuffy
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Post by jakesrocks on Jul 4, 2010 18:11:24 GMT -5
To add to what Ken said, The old type rotary flat laps had a cast iron wheel with grit and water dripped onto the wheel. With every grit change the wheel had to come off, and it and the tank had to be scrubbed out, or risk cross contamination. A time and labor intensive process. With most vibratory laps it's just a matter of undoing a couple of bolts, lifting the pan off, and washing it out with the garden hose. Then bolt the pan back down and start with your next grit size. Don
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Post by johnjsgems on Jul 5, 2010 8:32:47 GMT -5
Don, the old style lap we used (18"HP) had a 4"or so lip around top we would cover with newspaper. At grit changes the paper was removed, the steel lap plate rinsed in place and new paper added. Three people could use it at once providing everyone was on same grit. We used old restaurant salt shakers or jars with holes in lid for grit shakers and there was a water drip. You could tell by sound when you needed to add new grit. The laps ran fairly slow to avoid slinging grit off. Diamond Pacific still makes these in 12"and 18"in SC and diamond magnetic disc models. Covington makes a 16"model.
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Post by jakesrocks on Jul 5, 2010 9:53:42 GMT -5
The only problem with the magnetic diamond disks is the expense. Just the 6" mag disks for my Genie set me back several hundred dollars. The mag disks for a larger machine would be great for someone who was going to be using the machine constantly, but for occasional work the cost is prohibitive. I bought the 8" inland flat lap a few months ago, and sprung for the whole set of diamond disks. It doubled the cost of the machine. On the plus side for rotating flat laps, They're cheaper to buy, and with a little extra work, cutter cups can be added to the central shaft to make a primitive sphere machine. Diamond Pacific bought H.P.'s patterns. What they are selling now is a prettied up H.P. machine. My 20" H.P. Vibro-Lap is exactly the same as the 20" model being sold by D.P., and all of the parts are interchangeable. The only difference is that D.P. added expanded metal guards around the bottom of the frame, and changed the color. Don
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Post by jakesrocks on Jul 5, 2010 10:38:08 GMT -5
One other note. Just like the difference between rotary and vibratory tumblers. The rotary flat laps are much quieter running. I have to shut my flat lap off at night, so we can sleep. Don
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Post by johnjsgems on Jul 5, 2010 13:06:00 GMT -5
Our old HP had a polish cup that went in place of the lap pate and people polished spheres with it. I had a chance to buy a used one time HP lap and kick myself for not buying it. They wanted $300 with "a lot of rocks thrown in". I drove an hour to find "a lot"meant a bucket and a half and they wouldn't budge on the price. I really like them but most people don't want them anymore.
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Post by jakesrocks on Jul 5, 2010 13:25:49 GMT -5
I had a friend that turned up to bowling ball sized spheres on an old flat lap, using nothing but an adapted plumbing bell reducer and a leather glove. Got my H.P. vibro-lap, a 24" H.P. saw, a flex shaft, motor and handpiece, several other small tools, a couple boxes of findings and silver wire, a 10' long work bench and around 800 lbs. of rock at an estate sale for $1,000.00. Didn't have room for the saw, and sold it for $1,300. But deals like that are few and far between. Don
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Post by johnjsgems on Jul 5, 2010 17:35:32 GMT -5
Don, I hear of deals all the time. I always hear a little too late though.
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Post by jakesrocks on Jul 5, 2010 18:54:37 GMT -5
I've managed to hit it right on a couple. The last one was over a ton of old stock rock that a guy had collected from all over the country. Got a bunch of Willow Creek and Bruneau in that one, along with a 20 odd pound chunk of electric blue obsidian. Don
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