Hello everyone! I am still new to lost wax casting but have a
question that I haven’t found answers to elsewhere. Once I have made
my ring model and the mold, how do I make the ring a custom size for
a customer? For example, imagine that I have a design that I want to
offer in a variety of ring sizes. How do I change the ring size of my
wax model? Do I just cut the wax and reattach the ends?
Thank you so much!
Ok there are two options one is to make your ring model in all the
sizes you want in wax form. generally I have seen that the same
design was made into a mold for each size. I want to be able to have
flexibility as you do so here is what I did. I made the design
carving then I laid the ring band flat as it would be pre-hammered
on a ring mandrel I made the length of the band long enough so that
when formed and soldered I could cut the length to fit sizes 5 to 12.
This is my plan not sure if it will work but my biggest complaint is
I love that ring but you don;t have my size. Also make your bands
strong. My rings are heavy so that at shows I can enlarge a band
quickly and fit a ring to someone who needs up to a half size
bigger. That way a 5 is a 5-5.5 etc.
Teri (waiting to hear from the ancient ones 
)
How do I change the ring size of my wax model? Do I just cut the wax and reattach the ends?"
That’s about it though the process is much easier with a plain shank
on the ring. It’s much easier to size down than size up because you
don’t have to insert a piece to match the shank profile. Hence make
your mould for the largest size you intend to make. Obviously the
ring design needs to be considered when establishing a suitable size
range since it really needs to look in proportion.
I usually cut the shank at the sprue attachment point because this
area has to be cleaned up after casting. Place the ring on the
mandrel a half size up from the final size you want. Then cut the
excess shank and weld together while on the mandrel with a heated
probe or wax pen. Weld on a wax sprue over the welded joint.
Finally, remove the pattern from the mandrel and clean and smooth the
weld and sprue attachment point using whatever tools you use for the
purpose. I use a scalpel with a small triangular blade and a wax pen.
I then use some orange oil on a cotton bud (Q tip for US readers)to
give a polish.
Happy casting
Jen
I guess I’m an “ancient one”, since I have been sizing wax pattern
rings since 1978 or there abouts.
All the major tool suppliers and wax suppliers sell sets of
cylindrical half and whole aluminum ring sizes with a stand that are
very useful for sizing your waxes. We usually cast the original ring
in a size that is about as large as we would normally sell; 12 1/2
for men, and 9 for ladies rings. Waxes are easier to size down than
up. We make one or more vulcanized molds of each ring. Personally, I
prefer Belcone silicone mold rubber (Rio Grand has it).
I use a scalpel to cut the wax shank. If it’s going up several sizes
I inject 2 rings and splice in a piece to fill the void. You could
use a ring mandrel on a stand for this, but keep in mind that the
ring mandrel is tapered. This is really only a problem with wide
bands. We use an electric wax pen to join all ends, and build up the
wax a bit everywhere over the joint. This is all ground off as excess
metal in the clean up after the ring is cast. Clean up the inside
first, so you can tap the ring to the proper size. They shrink a bit
in casting, so the size comes out slightly smaller.
If your ring has a pattern all the way around, and you plan to be
selling lots of them in various sizes, it really pays to make molds
of each whole size. It’s not very hard to size a ring up 1/2 size
after it’s cast, in most metals; so that’s how we do 1/2 sizes and
1/4 sizes. If you size aring in the wax with a pattern, you will
need to fix, complete, re-carve the pattern where you sized it.
Hope this helps,
Paul; Ancient of Days
Thanks Paul great explanation of the process. I am just at the very
beginning of learning about wax carving. I thought with my sculpting
background it would be worth a go and I will go add the ring tools to
my wish list. Waves at Rio lol
Teri
Hi, the easiest way is to use a wax reamer made for the job. It looks
like a ring size stick but has a cutter on a flat that works a little
like a pencil sharpener. Cant remember the make of mine off the top
of my head.
Nick royall