No-one likes general adverts, and ours hadn't been updated for ages, so we're having a clear-out and a change round to make the new ones useful to you. These new adverts bring in a small amount to help pay for the board and keep it free for you to use, so please do use them whenever you can, Let our links help you find great books on glass or a new piece for your collection. Thank you for supporting the Board.

Author Topic: Cause of Common Manufacturing Fault to Flower Frogs - Sowerby  (Read 548 times)

0 Members and 1 Guest are viewing this topic.

Offline thomasandkatherine

  • Members
  • **
  • Posts: 50
Cause of Common Manufacturing Fault to Flower Frogs - Sowerby
« on: October 20, 2009, 12:24:10 AM »
I recently received the question set out below regarding the common manufacturing fault found on the underside of the flower holes on english flower frogs or blocks, in this case a Sowerby frog.  Does anyone know the answer to the question, my guess is that it has something to do with the removal of the glass from the mould, but I am not sure:

"Got a question for you: 
underneath the frogs, on some of the holes, are odd-looking flakes, as if
someone shaved glass away.  The same effect as when a glass marble breaks. 
Can't be damage; because of the way frog is made, couldn't be impact chips
in the hollow. 

Do you have any idea what they are or why they're
there
?"
Alison Robley, Australia

Offline Lustrousstone

  • Members
  • **
  • Posts: 12195
  • Gender: Female
    • Warrington, UK
    • My Gallery
Re: Cause of Common Manufacturing Fault to Flower Frogs - Sowerby
« Reply #1 on: October 20, 2009, 11:25:50 AM »
They are there because the the holes were drilled through from the top when the glass is cold and not quite enough care was taken. The holes are only partly made in the mould. Creating moulds and processes for holes right through was more costly than a man with a drill. These were obviously perfectly acceptable at the time as were annealing flaws and shear marks.

Offline thomasandkatherine

  • Members
  • **
  • Posts: 50
Re: Cause of Common Manufacturing Fault to Flower Frogs - Sowerby
« Reply #2 on: October 20, 2009, 11:45:12 AM »
Brilliant, many thanks.  That explains partially drilled holes on some items also. Thank you again
Alison Robley, Australia

 

Look for glass on
 ebay.co.uk 
Look for glass on
 eBay.com (US)

Link to Glass Encyclopedia
Link to Glass Museum


This Website is provided by Angela Bowey, PO Box 113, Paihia 0247, New Zealand