You result will be the clincher, Josef.
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You result will be the clincher, Josef.
Wow, I would not expect anyone to cast rings just for testing, thanks a lot!
Will be exciting to see the results! :)
/Andreas
Just to add more to the confusion, when measuring - for instance - hot hands, or "time of the month" can make a difference of a size or two.
Attachment 6741
Raw castings trees
Attachment 6742
the wax model, 18 ct white gold, and platinum rings cut from the tree
Attachment 6743
The wax for comparison size N
Attachment 6744
Platinum raw casting M (ish)
Attachment 6745
White gold M(ish) bit of a wobbly cast that one !
Attachment 6746
Both rings with the inside cleaned up ready for hallmarking
Attachment 6747
Platinum M 1/2
Attachment 6748
White gold M 1/2
Hope this helps
So Josef, the rings became about one size smaller after casting, but removal of metal when polishing the inside caused them to end up a half size smaller.
This is what you predicted at the outset, when you said the wax should be a half size bigger than needed. However the The models made with a 3D printer are rougher than wax and need more finishing. So it is possible that rings cast from wax might need to start three quarters of a size bigger.
Also heavier rings will shrink more, so will need a further estimated allowance.
Thank you for clarifying the problem for us. I hope I have summarised it correctly. Dennis.
That Josef is a really useful demonstration of the debate, thank you for taking the time to do it, document it and share!!
Very much appreciated :)
Hi Dennis that sounds about right,but I still would only go half a size on average size grown rings as depending on which direction the rings are grown on the machine the grow lines effect it differently,I dont have a formula for this it just seems to work out ok. But if you need to make the ring to a certain dimension say for example a 3mm band its better to have a bit of meat on it to finish to the correct thickness so I would add a bit to the outer dimensions
No problem Tabby glad to help. I just hope the ring fits Icarleug If Im in doubt I always go bigger at least she can put it on then get it resized as opposed to not putting it on and getting it resized !
Really interesting thanks for sharing!