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PostPosted: Wed Dec 13, 2006 3:17 pm 
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Biased? I take exception to that statement.

You do not like my reviews that is fine. List facts and what you do not agree with. What exactly? Have you cut and used the machines in question or in my reviews? If so then be specific and give an opinion on the machines.

You are also welcome to do your own reviews and come to your own conclusions. I state in my reviews that other people may have different opinions. If you do, say so, but give us some facts. What? why?

My machine reviews are here for any one that wants to read them.
http://www.faceters.com/askjeff/

As for Rob at colorwright, you are wrong, he lists most of the machines made, but he does not sell them.

He lists them for advertising purposes to draw traffic. But he does not sell Ultra Tec (has not in a long time), Facetron, Graves, Polymetric. The only faceting machines he sells the last time I checked was Alpha Tarous (which I recommend against and will not sell) and Facette which is a decent machine but pretty expensie. Go check...

As for OMNIe if you have never seen or used one you are shooting in the dark and have no idea of what you are talking about. Actually use one and then we can talk... Until then you do not know, you are just speculating.

ALL faceting machines will wear over time. That is how it is. Any one who
says different does not know what they are talking about. Expect to have to do maintence on any machine sooner or later.

They will all require some adjusting and some bearing replacements
eventually (one thing to consider is the costs, which for an UT, I can tell
you from personal experience my dealer cost was $650 2 years ago when I had a 8 year old machine of mine done. They were just a bit loose from normal wear). Again expect to have to do things like this on any machine, any brand. Keep in mind I probably cut a lot more than the average person.

That being said, you will usually cut a long time before needing to do
anything (on a new machine) unless you have an accident (stub the head, drop it ect...). The big thing to look for is can the machine(s) can be adjusted, the UT and the OMNI both can be. Some others cannot be.

The swing arm on the OMNIe is on a heavy duty bearing (that can be adjusted) so no, there is no metal to metal and no wear. Yes, some day the bearing will wear and need adjusting and can be replaced.

On any other machine, like and Ultra Tec the mast slides on the aluminium base (which cutting dust usually gets under and acts like grit), eventually the base(s) of the mast and the plate will wear from the friction of the sliding and the mast will have to be shimmed. I had an older used UT I had to shim more than once. Also the mast and screw needed to be shimmed. The yoke has 3 screws for some adjustment. But this is normal wear.

The same flexing (which is not much) will happen on almost any mast, the
loads and table cutting being virtually the same when you facet any stone on any machine.

This is all normal wear and while machines may differ a little on what wears they all will. Just differently.

I have sold and used both machines and they are both good machines. However for the money the OMNIe is by far the better buy. The OMNI is $2195.00 for the 8" the UT is $3380.00 last time I checked. The 220V on the OMNI is the same price the 220V on the UT is $200 extra.

Do the math there is a 33% diference in price. That is huge. Also the
machining on both is quite good. The UT is maybe a little fancier, but no
better in function. Also the UT uses wierd threads and parts (one of my
biggest complaints about them) that you can only get from UT. A simple screw cost me (a dealer) $9.

I have talked to Joe Rubin the owner more than once about this stupid policy, it is not a major complain but it irritates me. I have told Joe that standard threads and sizes should be used, that way a customer can easily replace things locally and reasonably. I have not won the argument.

No I do not carry the UT any longer, Joe demanded I only sell his machine no other machines or I could not sell his machine. I told him what I thought of his demand (stupid, short sighted, black mail)... So I do not carry the UT.

Joe and I disagree on his policy and frankly I would not let any
manufacturer get away with that type of crap. So I do not sell UT.

I have used both, I like both machines. They both cut well and from a cut stone perspective you could not tell the difference. Working on either machine is a little different but not much. I would note that many cutters consider the swing arm a major convience and speed advantage. Many people do not like the screw height adjustment on the UT and so on...

Take the money difference and you can buy rough, the rough you buy will pay for the machine many times over once you have cut it. Assuming you buy quality material and cut it well.

For what it is worth I would say buy an OMNIe (the USA one). The other
decent machines are UT, Facette, and maybe a Facetron. But the rest of the machines available I do not recommend.


Jeff
www.faceters.com


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 Post subject: Re: Best faceting machine?
PostPosted: Wed Dec 13, 2006 5:26 pm 
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gemdoug1 wrote:
By the way -- speaking of jam-pegs -- I'm in the middle of building one for myself (I've always been so fascinated by them that I've decided to set that skill as the next on my agenda), and am wondering if anyone else on this forum has access to any old Jambs that might be for sale. I'd prefer to learn on the traditional equipment than build something more high-tech, if at all possible. Suggestions?

Hi Doug,
I know several Brasilian gem cutters who use German-designed jamb-peg machines. They turn out exceptional stones very quickly from carefully-made preforms. Sometimes the preforms have a bit too much pavilion weight but most of the guys turn out great critical-angle cutting.

One such machine was for sale a couple of years ago but I had no room for it and no real inclination or need to learn that cutting style. I'll ask one of the cutters if I can shoot some pictures, perhaps to serve as inspiration for your project.

Rick Martin


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PostPosted: Fri Dec 15, 2006 12:05 am 
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Folks,

The original question from BrimsJewelry was what was the best faceting machine. There may not be a best, but a number of machines that are very very good.

But one thing that ought to be considered is how repeatable the machine is. By that I mean if you cut a tier at 34.25 degrees on one tier and move on to another tier at another angle, can you go back to 34.25 degrees if you need to, such as when polishing? I know of one brand that many of the folks who have it cut a tier all the way through polish before moving on to the next tier because they cannot depend on the machine to return to any specific angle setting.

Next, how convenient is the machine to cut all facets in a tier to the same exact depth? Here I mean cutting the first fact in the tier to the proper depth and cutting all the other facets in that tier to the same depth, give or take a millionth or so. This is where the various gauges/indicators come in. It is really great to be able to cut a facet until some indicator points to the same value as the first facet without eyeballing each and every facet in that tier. It's a lot faster and usually a lot more exact than eyeballing.

The Facetron now uses a dial indicator, and the Fac-Ette uses some kind or meter that I don't know the name for. only that the folks who use it are exceptionally rabid about how good it is. With the present $1000 discount on the Fac-ette it costs about the same as the UltraTec.

But there is a better and MUCH less expensive approach that can really improve any machine. It's called the "The Beale/Woolley Depth of Cut Indicator " and you can read about it here:
/www.rockhounds.com/rockshop/gem_designs/bw_indicator/

It uses an inexpensive ohmeter (or multimeter) that goes for $10 at Sears and is extremely effective.

John Rolf, who was building custom faceting heads and using electric "pots" to measure angles for repeatability on both angle and depth of cut said last month"

"Good point. It should be remembered that the Beale-Wooley Meter can
resolve Microns. Best of all it does so repeatedly, so people use them
for finish cutting all the time.

But the BW Meter provides a unitless relative number that is some
integral of contact noise, resistance, elastic modulus and Force.

It probably has one of the highest resolutions of all the systems out
there, and is repeatable.
It IS accurate in a relative sense, but not neccessarily directly
proportional to angle."

You cut the first facet to the proper position and depth, note where you are on the B/W meter and cut all the other facets to that same point. They will all be the same.

The good news is that putting a B/W on a faceting machine is (usually) inexpensive. It cost me about $15, as I bought a big old analog multimeter on eBay so as to have a bigger meter face than the 35 year old pocket Sears analog multimeter which I started with. On my UltraTec, one lead goes on an existing screw and the other is rubber banded to another hand screw. Simplicity. It makes any machine better.

Such a capability really makes life easier and faceting faster without sacrificing accuracy. Any machine you consider you might want to be sure that you can put a B/W on it .

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PostPosted: Fri Dec 15, 2006 2:00 pm 
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Facetor, is someone selling plans or parts for this B/W device?


In response to Jeff.... I us the Alpha Tourus which you strongly recomend not to buy. I love my machine. I have cut over 1000 stones on it, have never needed to have any work or adjustments done to it. I also know 2 other people with them and they both love them, and have never had any problems. So I guess I'm not sure why you strongly steer people away from the machine. I have found it very easy to use, very accurate and reliable, and Nick the builder is lots of fun to talk to.

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PostPosted: Fri Dec 15, 2006 4:09 pm 
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Colorwright is getting out of selling faceting machines.. according to rob, it's nothing but grief for him, and lousy customer service.. apparently we facetors are just barely on the radar for some of them as they are selling the same machine for $12k - 20k to the fiber optic polishers.. same thing w/ Crystalite... anyway that's what he reports..

I've heard nothing but egotistical horror stories about ultra-tek.. what surprises me is why someone doesn't get a lawyer on spec and make about $250k off that company for illegal restraint of trade... that's a fat pot of cash just waiting to be collected, and maybe put that egomaniac back in the box..

btw just found a $125.00 optical encoder that has a 1.25" form factor, 72,000 line, resolution, which is .005 degrees. Looks like it might make a nice digital readout for a machine ( as long as you debounce the lap warp). Can't be worse than the polymetrics..


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PostPosted: Fri Dec 15, 2006 9:42 pm 
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Precision Gem,

As far as I know the B/W is a do it yourself thing, except that Mr. Beale had some parts for folks for Graves machines, but that was a year ago...

What the B/W really is is an ohmeter (use the ohms setting on a multimeter) that shows the resistance to current between the two parts of a hard stop faceting machine.

Most machines now (include Facetron now with their latest model) are hard stop machines. As the lap turns, it is not perfectly flat nor are the diamonds in the surface perfectly the same height. This means that as you cut a stone and get close to the hard stop, the actual contact between the fixed and movable parts of the hard stop sometimes touch and sometimes don't. The closer you get to the hard stop the longer or more frequent the contact is. It is very important to use an analog meter, a digital meter will not work as it takes samples too often for too short a time. In general a digital ohmeter will show 0 or 1000, in other words complete resistance or no resistance (0).

An analog meter lags and kind of summarizes the on/off contacts. As they become more frequent, the needle moves closer to zero. So if you cut a facet and set the hard stop so that the needle is say at 2 (out of 10) when that facet is done, you cut all the other facets in the tier to a meter reading of 2 and they will all be very very close to the same.

So what you want to do is connect one lead from the ohm.multimeter to the movable part of the stop and the other to the fixed part. On an Ultra Tec this is very simple, as the two parts are electrically isolated from each other. On some machines all the head is connected so there is always a circuit between the two point, so the meter always reads zero resistance.

What you need to do is figure out how to connect the leads to read off of the hard stop only. Much of the article referenced in the earlier post talked about how this was done on a Graves.

You might want to go to the USFG (US Faceters Guild) Yahoo list and ask there if anyone has a B/W on your brand of machine and how did they hook it up? This is what I did and I got quite a few replies. It took me only a few minutes to hook it up on my UT.

One additional thing you can do with a B/W is find out how flat your laps are and if your mast is crooked. Turn on the lap at medium speed. For the first, move the height adjustment so the needle is in the middle of the meter and sweep the stone from rim to center and back. Does the needle stay the same? Does it indicate higher resistance (the lap is lower/farther away) at the rim or the center, Or does it go to zero at some point on the lap. That point is the high area on your lap. when you want to make those final very slight corrections to the meets, you want to either stay away from that area, or use it. But you know where it is.

To check your mast, put on a master lap and check for level as above, with the stone gong from rim to the center nut radially, (from the rim straight into the nut). Then move the mast back so the stone clears the nut and sweep from rim to rim (BE CAREFUL, part of the time you will be holding the stone against the rotation, so hold it carefully) If the mast is crooked, the readings on the two rim locations will likely be different.

It's actually easier to do this with a dial indicator clamped to the quill and the lap not revolving. I've done it both ways and the B/W was more sensitive than the dial indicator which really only indicated 1/1000's differences.

Outside of any modifications to your machines, a cheap meter works about as well as an expensive one so you can do it quite well for $10.

One person I know had a machine which did not look like he could hook a B/W up to it, so he epoxied a metal strip cross the hard stop contact (it could no longer move at all, and then cut through the strip with a Dremel.

The epoxy kept the two pieces of the metal strip from electrical contact with the machine, but the contact between the two pieces of the strip mimicked the hard stop and it worked.

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PostPosted: Fri Jan 08, 2010 2:40 pm 
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This is a good thread.
I had been kinda looking around for a new machine, after over thirty years on my Prismatic, which was getting to the point of untuneable.
Fortunately, shimming the bushings in the mast has restored it to like new performance.
Does anyone know why the late Jeff Graham would not recommend the Prismatic/Poly-Metric machine, or does anyone else have an opinion of them to offer?


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PostPosted: Fri Jan 08, 2010 6:29 pm 
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The Poly-Metric machines are top notch IMHO. I own the Scintillator and the OMF and love them. The Scintillator is a beast of a workhorse as well as a piece of art, lol. Lots of attention to details in the machines, obviously. Zane is very passionate about his machines and puts great care into building each one and his customer service is phenomenal to say the least! I did many years of research into my decision, had originally been looking at an Omni-e and decided against when I found out the issues many have had with customer service and main bearing issues. Maybe if I was more experienced, but not a beginner machine. The Polymetric machines are great for beginners or pros. Same goes for the Prismatic machines from what I understand, but can't speak from experience.

If I had it all to do over again, I would still go with the Polymetric machine. I feel the Scintillator offers the best bang for the buck out there. Lots of nice little extras on it. And the transfer block is simply the best I have used and I love it!!! The Scintillator is a workhorse, and as my friend always says, you could prolly use the mast to jack up your car if you needed to, lol, it is that beefy! But joshing aside, it truly is a pleasure to use. The beefier dop arm I love, especially for my large hands and issues with grip. I don't have to fight the machine when cutting, it does what I want and need it too without needing to work around any quirks and/or issues so I can totally concentrate on faceting and enjoy it.

I could get into details about why Jeff didn't recommend them, but that is not my place. Just leave it at it had nothing to do with the machine, but more so with his idealistic view of how dealer support should be and he basically dissed the machines due to that. Nothing to do with quality or lack of quality. :/

But you can't go wrong with a Polymetric machine. And Zane Hoffman, the owner and manufacturer, goes that extra mile in build quality as well as customer service, and to me customer service is as important as everything else!! I also like the fact that he is not only assembling the machines but also actually making, laser engraving, and milling most all of the parts as well!!! The designs haven't changed much but why fix it if it ain't broke, as they say! :).


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PostPosted: Sun Jan 17, 2010 11:36 pm 
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I think the Prismatic is a well made machine, it seems very sturdy and well machined.

However, I do not like the design.

I do not like how the mast is so close to the faceter in relation to the lap, all other machines I have used have the mast further back from the front of the machine and this seems more comfortable and natural to me.

Also the leadscrew takes far too long to wind up and down. The Ultra Tec (my favorite machine) takes a little longer than ideal to wind up and down so this is something I pay attention to. (This problem is fixed with the new optional fast leadscrew that they are making which will probably become standard at some future date, I have tested it and love it.)

In looking at the polymetric machine it seemed like the thread on the leadscrew had a very steep pitch so I assumed that it would be fast to raise and lower the head. Until I used one that is, then I discovered that the drive is geared and this slows it WAY down. This may be an attempt to help with accuracy but IMO it is unnecessary and a big time waster. It was FAR slower than the Ultra Tec, even before the new faster leadscrew.

I only used the machine to cut one gem but there were some other aspects of the layout and drip pan setup that I did not like either.

That having been said I hear that the guy who makes them is a real gem and has great customer service. So if after having used one and compared it to others you like it personally you will probably be fine with it.

I also hear that his transfer jigs are really nice and am considering buying one for extra large gems that don't fit in my standard UT jig.

(Disclaimer, I am an Ultra Tec rep but this is my honest opinion. Take it for whatever it's worth.)[/i]

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https://www.johndyergems.com
Artisitic and designer cut gems

https://www.ultratecfacetingmachine.com
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PostPosted: Mon Jan 18, 2010 12:20 am 
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johnddyer wrote:
Also the leadscrew takes far too long to wind up and down.

The interesting thing to me is that some machines (my Graves 5XL, for example) manage just fine without having to crank the head up and down. What is the advantage of the lead screw?


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PostPosted: Mon Jan 18, 2010 3:39 pm 
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FYI, the new design on the Scintillator has a fast release for the head to go up and down, no reason to crank. The crank is ONLY for precision. If you push the knob on the head in it releases it from the screw and allows you to freely slide it up and down on, so there is no slowness about it at all, just the opposite actually. :). To me the design on it is perfect. Until I found out about he push button release from a phone call to Zane, I didn't like that part a whole lot either, lol. But once knew about the release I love it! And I find the gear precision to be quite nice, personally, when setting up my angles and such. But everyone is different and likes different things. Just wanted to clarify that there really isn't an issue with the head movement up/down due to the release button.

I also forgot to mention one other feature I like, not sure if present on other machines or not honestly, but I love the freewheel pin on the Scintillator allowing it to spin freely for preforming girdles and such.

John, can I inquire as to what about the drip pan and system you didn't like and the layout? Just curious. Thanks.

As for the transfer jigs, get one!!! You will NOT be disappointed at all!


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PostPosted: Mon Jan 18, 2010 3:54 pm 
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Swishman wrote:
FYI, the new design on the Scintillator has a fast release for the head to go up and down, no reason to crank. The crank is ONLY for precision.


On the Graves machine, the collar holding the head slides freely, with a clamp screw. Precision is obtained using a micrometer. It works well. Sounds like a similar system.
Quote:
I also forgot to mention one other feature I like, not sure if present on other machines or not honestly, but I love the freewheel pin on the Scintillator allowing it to spin freely for preforming girdles and such.

I think that's a pretty common feature. I don't use it for preforming, but it's nice for that final inspection of the tier you've just finished.
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As for the transfer jigs, get one!!! You will NOT be disappointed at all!

I have two Polymetric transfer jigs. Best in the business, IMO.


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PostPosted: Mon Jan 18, 2010 9:00 pm 
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Hi Swishman,

I am glad that he got that issue fixed.

As to the splash pan I did not like that is was made of relatively hard plastic and the way it is made in two parts did not appeal to me either. On almost any machine the drain hose plugs up with gem dust at times and I like the splash pan to be able to fill up until it the point where I notice it before it starts spilling water out. Also anything that is hard at all (even hard plastic) can break a gem if the culet whacks into it. I like the rubber splash guards some machines have better.

The other thing I did not like was where the mast was on the machine, too close to the front IMO. It was not as comfortable to use as most other machines with the mast closer to the middle of the machine, this lets the arm extend a little more in a natural way without having to sit super far back from the machine.

As Al Balmer mentioned almost all machines have the free wheel option.

Once again, I do not want to make this sound like it is a bad machine. It is not, rather it is a well made machine with some design issues that make me prefer other machines over it.

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Gems are purchased because they are pretty, so they should be as pretty as possible!

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Artisitic and designer cut gems

https://www.ultratecfacetingmachine.com
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PostPosted: Tue Jan 19, 2010 1:37 am 
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John,
Thanks for your opinions on what you didn't like. I am the opposite and like the splash guard being in two pieces, much easier for cleaning. Being hard can be an issue I admit, I had a nice Virgin Valley blue opal fly off and crack after hitting the bowl, :(, but I can live with it as it doesn't happen much to me so far.

As for the hose clogging, on the Scintillator I have not had this issue yet truthfully, even when cabbing and removing lots of material sometimes no clogs yet, seems to work very very well however it is setup, not exactly sure. Maybe I have just been lucky, no clue.

As for the position of the mast, I guess that depends what you are used to. Since I never spent a whole lot of time on any one machine except for the Scintillator, I haven't had issue with its placement. But I can definitely see how if one is used to a different placement it could be a bit uncomfortable to use.

I know you're not making it out ot be a bad machine. I just always like to hear why ppl like or dislike equipment, lol. I am a very inquisitive person is all, sorry if I made you think/feel otherwise.


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PostPosted: Tue Jan 19, 2010 2:02 pm 
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OK, that's fine.

The question was asked so I tried to answer it.

I would rather not talk more about it though since I don't want to be badmouthing someone's product.

(Unless of course you want to hear what I DO like about another machine, that way we can go from negatives to positives.) :wink:

Happy faceting!

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Gems are purchased because they are pretty, so they should be as pretty as possible!

https://www.johndyergems.com
Artisitic and designer cut gems

https://www.ultratecfacetingmachine.com
Authorized Ultra Tec dealer.


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