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Deep Concave Cuts, Is It Possible?!?

cutting glass deep concave deep concave help!

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#1 smolt



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Posted 10 February 2017 - 12:15 AM



I am wondering if the cuts in the attached images are possible. They are deep concave cuts.




The concave for piece 1 is about an inch and the concave for piece 2 is about 1/2 inch





The concave for piece 1 is about 5/16 inch


Piece 2 just has a sharp and thin edge and am wondering if that is possible.



Thanks for any help you can provide!!!!


Attached File  deep_concave_question1.jpg   67.72K   7 downloads


Attached File  deep_concave_question2.jpg   61.88K   5 downloads

#2 Knight


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Posted 10 February 2017 - 08:28 AM

Cuts like these are all based on experience and technique, so to ask if it is possible.....


If the glass is a buttery smooth, cathedral, handblown or super machined (spectrum) I think it could be done with a glass cutter and a good pair of grozing pliers and confidence. 


If you are new to the game, or not as experienced with chewing off the glass with pliers I recommend practicing on clear window glass, cheaper and easy to cut. I have several different sizes of grozing pliers to help with smaller areas that need removed.


Sometimes when I am doing a restoration I come across a piece that is cut at such an angle, or curve, or both, that I am really blown away. 100 years ago the option of taking the glass to a ring saw or grinder was not an option. I like to joke that they used their teeth to get the glass cut sometimes, that is what it looks like when you chew away mass with pliers. Give it a try sometime, if you get the hang of it the grinder becomes a thing of the past. I try to razz my newbies anytime they use the grinder, they learn that the cuts are able to be made with hand tools and it ups their skill immensely!

#3 Mt_Top



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Posted 10 February 2017 - 10:58 AM

Stress fractures.  You may successfully make those cuts, but months/years down the road they crack.  Consider doing overlays.   In Pic #1 piece #1 could be circular in shape, no stress points.  Then piece #2 is cut, again mostly circular and set on top of piece #1, soldered in place (easy to do if this is copper foil).  Then the long skinny oval shape is set on top of piece #2 and soldered in place.  If piece #1 is cathedral, piece #2 is semi-opalescent and the oval piece is dark opal, you would not see the lines covered up by the stacked glass pieces. 


It's always good to consider other building techniques, they may solve construction problems and also add interest to a project.

#4 annabelle



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Posted 11 February 2017 - 03:34 PM

Knight & Mt Top both make valid points..I agree with them...I like the suggestion to make the claw an overlay.  It could even be a copper foil overlay.  Those toes on the second picture look pretty challenging.

#5 smolt



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Posted 11 February 2017 - 06:10 PM

All of this is very helpful! 


Thanks for all of your input!

#6 Tod Beall

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Posted 12 February 2017 - 08:00 AM

You could probably use your grinder to get what you need. It's not always the best idea, but here may be the right place for it.

#7 vrinner



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Posted 15 February 2017 - 11:48 AM

Here is an example of some deep cuts that I did...any by cuts I should actually say grind. I used a pointed grinding bit. If you notice that the teeth look very sharp and pointy but in reality they do have some curve in them. I cut the foil into a point kind of like what Annabelle mentioned above with an overlay.


I also think the long term stress factor will also depend on how big the piece is and where/how it's installed. I did this piece about 4 or 5 years ago and it's still fine.



#8 KenRim



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Posted 15 February 2017 - 09:53 PM

I would think a ring saw would do just fine! Not cheap, but if your in a club, they may have one.

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