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curving

• Fiona Sands

  

  Member
   

  May 19, 2015

  Good afternoon

  I am making bird shaped brooches, around 4x6.6mm.  I cut out the shapes from 0.5mm copper, I counter enamel the back first with one coat.. then switch to the front and enamel with 3 or 4 coats.  I am finding that the flat shape is bending slightly outwards on the outside enamelled face... so that is is not perfectly flat.  How can I counteract this or is it just 'the nature of the beast' :)

  Thanks

  Fiona

  Good afternoon

  I am making bird shaped brooches, around 4x6.6mm.  I cut out the shapes from 0.5mm copper, I counter enamel the back first with one coat.. then switch to the front and enamel with 3 or 4 coats.  I am finding that the flat shape is bending slightly outwards on the outside enamelled face... so that is is not perfectly flat.  How can I counteract this or is it just 'the nature of the beast' :)

  Thanks

  Fiona

• Trish White

  

  Leader
   

  May 19, 2015

  If you are going to put 3 - 4 layers on top, you need more than 1 coat of  counter-enamel - Think  "Oreo cookie"  - chocolate cookie top and bottom are the enamels and the metal is the cream in the middle.

  You have a heavy top layer of enamels not equal to the bottom and there is a whole lot of movement going on as the glass and enamel heat and cool.  Always sift at least 2 layers of  counter - enamel on the bottom.

  The warping of the edges happens as the enamel layer melts , the metal softens and is drawn down by the weight of the enamel - thus  the edges bend up on the trivet. You can solve this problem by either turning the piece upside down on the next firing and if that does not help, use a flat steel block or old iron to press the piece flat when it comes out of the kiln. It should be flattened quickly before it cools. I have purchased old antique cast irons at flea markets and they make a great flattening tool.

  If you are going to put 3 - 4 layers on top, you need more than 1 coat of  counter-enamel - Think  "Oreo cookie"  - chocolate cookie top and bottom are the enamels and the metal is the cream in the middle.

  You have a heavy top layer of enamels not equal to the bottom and there is a whole lot of movement going on as the glass and enamel heat and cool.  Always sift at least 2 layers of  counter - enamel on the bottom.

  The warping of the edges happens as the enamel layer melts , the metal softens and is drawn down by the weight of the enamel - thus  the edges bend up on the trivet. You can solve this problem by either turning the piece upside down on the next firing and if that does not help, use a flat steel block or old iron to press the piece flat when it comes out of the kiln. It should be flattened quickly before it cools. I have purchased old antique cast irons at flea markets and they make a great flattening tool.

• Fiona Sands

  

  Member
   

  May 19, 2015

  Thank you Trish...  over the past couple of hours I engaged my brain and wondered about putting another layer of counter enamel.. I will try tomorrow with 2 layers and see what happens. The idea of using an iron is brilliant... mine will go into my studio tomorrow... I dont believe in ironing anyway :) Taught both my sons from the age of 11 how to iron their shirts.. lol

  Thank you Trish...  over the past couple of hours I engaged my brain and wondered about putting another layer of counter enamel.. I will try tomorrow with 2 layers and see what happens. The idea of using an iron is brilliant... mine will go into my studio tomorrow... I dont believe in ironing anyway :) Taught both my sons from the age of 11 how to iron their shirts.. lol

• Trish White

  

  Leader
   

  May 19, 2015

  Note:

  I would use an iron that does not have steam holes!

  Note:

  I would use an iron that does not have steam holes!

• Deleted Member

  
   

  May 20, 2015

  small stamp stainless steel

  

  small stamp stainless steel

  

• Edmund Massow

  

  Member
   

  May 20, 2015

  
  Another possibility is to form the pieces slightly convex. Convex side = sight-side. That makes the visual appearance a bit more pleasing and the piece more stable. Camber the piece before enamelling in a wooden dapping-block.

  
  Another possibility is to form the pieces slightly convex. Convex side = sight-side. That makes the visual appearance a bit more pleasing and the piece more stable. Camber the piece before enamelling in a wooden dapping-block.

• Fiona Sands

  

  Member
   

  May 20, 2015

  That too is a good idea Edmund... I wonder why objects are more appealing if they are convex rather than concave.  Im sure there is a reason, I just haven't read it yet

  That too is a good idea Edmund... I wonder why objects are more appealing if they are convex rather than concave.  Im sure there is a reason, I just haven't read it yet

• Edmund Massow

  

  Member
   

  May 20, 2015

   I would imagine that it is because convex objects make concessions to our spatial vision.

   I would imagine that it is because convex objects make concessions to our spatial vision.

• Fiona Sands

  

  Member
   

  May 20, 2015

  Im sure you are correct, but its also a touch thing as well.. convex feels nicer than convex on a one dimensional object..  May I ask where you got your dapping block from please..  I am trying out a turned wooden salt pot to see if that will work :)

  Im sure you are correct, but its also a touch thing as well.. convex feels nicer than convex on a one dimensional object..  May I ask where you got your dapping block from please..  I am trying out a turned wooden salt pot to see if that will work :)

• Edmund Massow

  

  Member
   

  May 20, 2015

  I think, you are right too.

  Wooden dapping block: You can get it for example here: http://www.ottofrei.com/search.php?mode=search&page=1 .
  Or "google" under "Wooden Dapping block" and then have a look into the picture search. There you'll  will find many supplier.

  Edmund
  http://www.emailkunst.de

  I think, you are right too.

  Wooden dapping block: You can get it for example here: http://www.ottofrei.com/search.php?mode=search&page=1 .
  Or "google" under "Wooden Dapping block" and then have a look into the picture search. There you'll  will find many supplier.

  Edmund
  http://www.emailkunst.de