It is with great sadness I'd like to announce Dr. Hanneman passed away on December 12, 2020. His legacy will live on forever!
Welcome to the GemologyOnline.com Forum
A non-profit Forum for the exchange of gemological ideas
It is currently Sun Jan 17, 2021 5:53 pm

All times are UTC - 4 hours




Post new topic Reply to topic  [ 14 posts ] 
Author Message
 Post subject: facet CENTER will not prepolish or polish
PostPosted: Sun Jan 03, 2021 7:30 am 
Offline
New to the Forum or The Quiet Type

Joined: Thu Dec 10, 2020 5:41 am
Posts: 9
hi there

im new obviously
the edges all polish like glass....the very center of each facet remains un polished
has anyone heard of this


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Sun Jan 03, 2021 7:29 pm 
Offline
Established Member

Joined: Sun Feb 09, 2020 10:52 pm
Posts: 39
Yes, I have seen this before when polishing with a soft lap if too much pressure is used. What essentially happens is the lap can "dish" or flex a little where it meets the stone. This causes the lap to make contact with all edges of the facet, but not in the middle.

If you keep polishing eventually you will get the facet completely polished, but this is NOT what I would recommend. You'll likely over cut your meet points if you do this, and won't have a nice flat facet in the end.

Try polishing with less pressure on the stone, or switch to a harder polishing lap if you have one available.


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Sun Jan 03, 2021 8:07 pm 
Offline
Gemology Online Veteran
User avatar

Joined: Tue Apr 05, 2016 7:58 pm
Posts: 509
Location: San Marcos, CA
Agree with Mike can happen. What do you mean by every facet? Is that meant like it sounds. Because that would be odd if that were the case. What is this stone your working on? Size, Shape and other info.

_________________
The Gem Garden
San Marcos, CA


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Sun Jan 03, 2021 11:16 pm 
Offline
New to the Forum or The Quiet Type

Joined: Thu Dec 10, 2020 5:41 am
Posts: 9
yes every single facet of the pavillion the center wont pre polish so ofcourse wont polish!! this is my second attempt and my second stone! I had to set aside the first stone i tried to facet (quartz) because I wore myself out and accidentally ruined (for now untill i resurface it) one side of my BATT LAP out of stupid desperation and ignorance!

Now i am trying to facet a piece of Flourite and Im getting same strange results. I have made progress however but i dont understand why this is happening...and i have spent HOURS with this Flourite because the only way i can prepolish ALMOST ALL OF THE CENTER OF EACH FACET is to move the mast ofthe arm forward and backwards and increase the degree by increments!!!

WHAT DEOS THIS SIGNIFY AND WHAT AM I DOING WRONG? i wont give up. Its a type of torture to look at this stone and see each facet reflecting light like a mirror EXCEPT ONE SECTION!! THE MIDDLE!!

I think i understand about the soft lap and that makes sense! the one good side of my BATT LAP is new and not broken in, not prepared in any way....but i guess i should try a facet with that as it is right? since its Flourite and so soft its been polishing with diamond paste 4000 (what i could polish of each facet that is!) but i had planned to use the BATT LAP with 50000 diamond grit as a polishing lap. Seems unnesesarry to use 50000 paste on this Flourite but I will just to find out if it is indeed tthe soft lap causing me to loose my mind.
Otherwise I have one ofthose made in china generic 3000 diamond grit....should I try that first? Its broken in from the quartz that i set aside.....


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Mon Jan 04, 2021 6:58 pm 
Offline
Gemology Online Veteran
User avatar

Joined: Tue Apr 05, 2016 7:58 pm
Posts: 509
Location: San Marcos, CA
Ast530 wrote:
yes every single facet of the pavillion the center wont pre polish so ofcourse wont polish!! this is my second attempt and my second stone! I had to set aside the first stone i tried to facet (quartz) because I wore myself out and accidentally ruined (for now untill i resurface it) one side of my BATT LAP out of stupid desperation and ignorance!

Now i am trying to facet a piece of Flourite and Im getting same strange results. I have made progress however but i dont understand why this is happening...and i have spent HOURS with this Flourite because the only way i can prepolish ALMOST ALL OF THE CENTER OF EACH FACET is to move the mast ofthe arm forward and backwards and increase the degree by increments!!!

WHAT DEOS THIS SIGNIFY AND WHAT AM I DOING WRONG? i wont give up. Its a type of torture to look at this stone and see each facet reflecting light like a mirror EXCEPT ONE SECTION!! THE MIDDLE!!

I think i understand about the soft lap and that makes sense! the one good side of my BATT LAP is new and not broken in, not prepared in any way....but i guess i should try a facet with that as it is right? since its Flourite and so soft its been polishing with diamond paste 4000 (what i could polish of each facet that is!) but i had planned to use the BATT LAP with 50000 diamond grit as a polishing lap. Seems unnesesarry to use 50000 paste on this Flourite but I will just to find out if it is indeed tthe soft lap causing me to loose my mind.
Otherwise I have one ofthose made in china generic 3000 diamond grit....should I try that first? Its broken in from the quartz that i set aside.....

You have just the opposite. Your trying to cut and polish a soft stone with hard laps. You will need very light pressure in all stages of faceting Fluorite. When cutting use very very light pressure, your creating a somewhat concave(cupping) surface, and when you go to polish it is only hitting the surface edges of the facet. Some would probably never achieve that effect if they tried. I admire your fortitude and persistence. By what your describing in your persistence of altering the angle trying to get the center is like a dog chasing its tail. You need a true cut flat surface to ultimately polish flat. There is a term in faceting for what your trying to do with changing the degrees on a facet trying to remove a blemish or small cat hair scratch, you end up with what is called ghost facets, there normally seen more on the tables, but can also be seen on larger facets.

_________________
The Gem Garden
San Marcos, CA


Last edited by glhays on Mon Jan 04, 2021 7:08 pm, edited 1 time in total.

Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Mon Jan 04, 2021 7:03 pm 
Offline
Established Member

Joined: Sun Feb 09, 2020 10:52 pm
Posts: 39
What were you using to try to polish the quartz? I'm assuming perhaps diamond based on your comments? I've honestly never tried to use diamond to polish quartz, but I've heard many people say it does not always work well.

I always used cerium oxide for quartz stones with good results on just about any type of lap (BATT, Lightning Lap, Ultralaps, Lucite(acryllic), Lexan(polycarbonate), Corian, and probably a few others too. Recently though I've been polishing quartz almost exclusively with Zirconium Oxide(again,on just about any lap) from Gearloose. It's noticably faster, and more consistent.

As far as the fluorite goes... that one can be tricky to cut/polish at times. I would not consider this a beginner stone. Again, I've never tried diamond with it as I've only ever heard of oxide polished being recommended. This is one of the stones that will often polish best on a very soft lap. I've heard wax laps work great(but I don't own one)

I don't know that these explain why you can polish the edge but not the center of a facet... but if you have a non-diamond polish available I'd give that a shot and see if you notice a difference.


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Mon Jan 04, 2021 7:12 pm 
Offline
Gold Member

Joined: Thu May 12, 2016 2:18 am
Posts: 1060
A BATT Lap is very hard. If it is flat it should pre-polish or polish a very flat facet. On soft stones it should cut to flat very quickly.

Your problem may lie in the lap prior to the BATT. It may be cutting a slightly concave facet.

Try this as a diagnosis.

Cut a few facets with the lap that you have been using prior to the BATT.

Use a Sharpie pen to coat the facets with a color.


Then quickly touch a facet or two the BATT with the lightest touch possible.

If it is just removing the color from the edges of the facets, then you have concave facets. Likely there is something wrong with the lap prior to the BATT.


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Mon Jan 04, 2021 7:14 pm 
Offline
Gemology Online Veteran
User avatar

Joined: Tue Apr 05, 2016 7:58 pm
Posts: 509
Location: San Marcos, CA
Ultimately it would be very helpful in helping you if you would provide us with your tool set of laps.

_________________
The Gem Garden
San Marcos, CA


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Wed Jan 06, 2021 5:18 am 
Offline
Valued Contributor

Joined: Wed Jul 22, 2015 6:39 am
Posts: 160
1bwana1 wrote:

Your problem may lie in the lap prior to the BATT. It may be cutting a slightly concave facet.




^this has been the root of the cause for me when this occurs.


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Fri Jan 08, 2021 3:25 am 
Offline
New to the Forum or The Quiet Type

Joined: Thu Dec 10, 2020 5:41 am
Posts: 9
how would i avoid cutting slightly concave facets? that was definately not my intention!


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Fri Jan 08, 2021 2:18 pm 
Offline
Gold Member

Joined: Thu May 12, 2016 2:18 am
Posts: 1060
Ast530 wrote:
how would i avoid cutting slightly concave facets? that was definately not my intention!


It is more likely to be a problem with the lap than it is technique.

Did you preform the test as I outlined?

If so what were the results?


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Fri Jan 08, 2021 3:45 pm 
Offline
Gemology Online Veteran
User avatar

Joined: Tue Apr 05, 2016 7:58 pm
Posts: 509
Location: San Marcos, CA
Ast530 wrote:
how would i avoid cutting slightly concave facets? that was definately not my intention!

Not to replicate it but... "Ultimately it would be very helpful in helping you if you would provide us with your tool set of laps."

_________________
The Gem Garden
San Marcos, CA


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Sun Jan 10, 2021 9:11 pm 
Offline
New to the Forum or The Quiet Type

Joined: Thu Dec 10, 2020 5:41 am
Posts: 9
well...thank you all for the advice!! Iam still trying to polish the flourite and because of everyones suggestions I took a look at my original quarts stone and I was able to see that I should not have quit when I did but I really was exasperated----its hard to learn from youtube and online books without someone to be there and correct what youre doing WHEN youre doing it.
I tried to prepolish the Flourite with diamond and it worked well with 4000 however there were still portions of each facet, not all in the middle, that would not polish. The scratches would not all polish out. So i tried Batt with 50,000 and honestly the prepolish 4000 did a better job (not on a Batt) but perhaps because the Batt is some what new?
So i decided to go back to 2500 lap and re cut.
Now that is finnished and i will once again pre polish and see if the deep scratches were eliminated and also i will see if it goes so well with the prepolish as it did lasst time. i am going to prepolish wwith same lapand 4000 diamond. i will update with results.


Top
 Profile  
Reply with quote  
 Post subject: Re: facet CENTER will not prepolish or polish
PostPosted: Mon Jan 11, 2021 1:13 am 
Offline
Gemology Online Veteran
User avatar

Joined: Tue Apr 05, 2016 7:58 pm
Posts: 509
Location: San Marcos, CA
Ast530 wrote:
well...thank you all for the advice!! Iam still trying to polish the flourite and because of everyones suggestions I took a look at my original quarts stone and I was able to see that I should not have quit when I did but I really was exasperated----its hard to learn from youtube and online books without someone to be there and correct what youre doing WHEN youre doing it.
I tried to prepolish the Flourite with diamond and it worked well with 4000 however there were still portions of each facet, not all in the middle, that would not polish. The scratches would not all polish out. So i tried Batt with 50,000 and honestly the prepolish 4000 did a better job (not on a Batt) but perhaps because the Batt is some what new?
So i decided to go back to 2500 lap and re cut.
Now that is finnished and i will once again pre polish and see if the deep scratches were eliminated and also i will see if it goes so well with the prepolish as it did lasst time. i am going to prepolish wwith same lapand 4000 diamond. i will update with results.

Sure glad we were able to help you get through the fustrations. Keep at it and by all means let us know how you progress. It may help someone else frustrations with a similar proplem.

_________________
The Gem Garden
San Marcos, CA


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 14 posts ] 

All times are UTC - 4 hours


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
Gemology Style ported to phpBB3 by Christian Bullock