Question for the Pros RE:Casting

[ame]

How long does it take to make a cast of a platinum ring? Custom ring that is.

 

[denverappraiser]

Ame,

The actual casting process takes less than a second. There are other related steps that can be very time consuming indeed. Sometimes the whole job from design to delivery can take less than a day. Doing it well can involve a lifetime of preparation and many weeks of detailed work. It will depend on the design, the craftsman and the materials involved.

Neil Beaty
GG(GIA) ISA NAJA

 

[ame]

Ok I was just curious. It always seems like custom work takes a long time. I didn''t know if it was related to the casting or the setting or the work in between. Setting seems to be fairly quick assuming the stones aren''t teeny tiny.

Thanks!

 

[oldminer]

I need a couple new gates put on my backyard fence. The gates are nothing much and will take about four hours to make and install. However, it took two weeks to get the estimate and another 10 days before the guy is prepared to show up. A lot of Custom Work is much the same. The workman usually has a backlog of promised jobs and likes it just that way. It is easier to plan one''s day and work week if there is plenty to do..... It is not extraordinary for customer work to take time even if the job itself is rather short.

 

[PhillipSchmidt]

Hi Ame,

It depends on the level of customisation you want. If the master patter is available, say a crown and a shank, then they can go into the next casting - from there the process is pretty fast. The casting is cleaned up, the parts assembled and it may be re-sized, then it should be polished before the setter takes over and polished again after. This is for a simple solitare so it it fast to produce, say 1 hour at break neck speed and 3 hours for fussy workmanship. I takes longer in hours if the setter is in a nother room or something like that, but 3 hours on the bench is enough for most simple pieces that don''t need much extra customisation. After that it depends on the stones, how many, what shape, etc and engraving adds to the total too.

If what you like is not readily availbale, then a master pattern has to be made and a rubber mould is made from that. A master pattern can take half a day to make (breakneck) or in more complicated designs a few days. Making a master pattern for a platinum ring does not save time, but it may save platinum waste and if the master pattern is a popular design there is always the chance that it might be used again.


Phillip

 

[mrssalvo]

I find this all very interesting. I think in read in countingdown''s thread that Mark morrell spent a total of 100 hours making his ring from start to finish.

 

[ame]

That''s insane. But to see that ring...wowza. That was WELL WORTH the time.

 

[LadyluvsLuxury]

Ok Ame, I don''t want to hijack your thread but I have a question related to this that may be completely simple and stupid to all the pros. When a cast is made is the cast actually the final product but just "in the rough" if you will? For instance if a ring is going to be yellow gold is the cast yellow gold but just unpolished? Also how does the wax go from being a wax to being a cast?

 

[ame]

Really great question. I wondered that too.

 

[denverappraiser]

The original model of the ring is carved in wax, plastic or some similar material and attached to the end of a small stick of wax about half an inch long. The other end of this stick is attached to a rubber base and a steel can about the size of a small coffee cup iis put around it.

The can is then filled with a material called investment, which is sort of like plaster and, after it sets up, the rubber base is removed. This makes a plaster cylinder with the wax ring in the middle and a stick of wax connecting the ring to one end.

This is put into an oven at a nice high temperature and the wax burns away leaving a cavity in the now hard investment where it used to be. Molten gold, platinum or whatever the final piece is to be made of is poured into the hole and it fills in where the wax was. The plaster is removed and you’ve got an exact copy of the original wax made of metal.

After the casting is done, it’s necessary to cut off the little stick of metal, repair any defects, polish the piece, assemble whatever additional parts are needed and set the stones. This same general process is used to make metal parts ranging from jewelry to cannons to the statues in the park and it’s been fundamentally the same for thousands of years.

It's not as easy as it sounds but the basics are quite simple. Like most things, the secret is in the details and a tremendous amount of effort has gone into figuring out how to do it well. You can get a PhD in this.

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[Kaleigh]

Thanks Neil, that was very well articulated, and I''m sure answered many of our questions!!!!!

 

[ame]

SO pretty much like that really screwed up sculpture of my hand...dunked in some rubber, filled with plaster....viola...instant hand.

 

[diamondsbylauren]

2-3 weeks is a good estimate for a cutom made three stone ring

 

[strmrdr]

For a high quality piece its my opinion that better than 90% of the time it takes should be spent once its cast.
Thats what separates the great from the crud.
CAD can be used then the wax "printed" on a machine then another machine can be used to cast it but there are no shortcuts it takes hard work, skill and experience to get an awesome finish.

 

[Garry H (Cut Nut)]

It rather amuses me that in USA custom made = carving a wax and casting as the custom mode manner. Yet here in Oz, custom made = hand made as in fabricated and wrought.
The great benefit of working with platinum by hand is that you can forge and fabricate it without solder by fusing it.

 

[PhillipSchmidt]

In heavy platinum pieces then a casting will often be OK, because the weight being forced against the overall pour will create a better defined shape. If the weight is relatively low then some of the definition will be missed (not as much in cobalt castings – if you like cobalt alloys). It goes to a pseudo PhD level if I go on. Overall weight and style of design is an issue, but the very best technically perfect jewels can be produced with some parts being cast.

To make a high class platinum piece by hand is incomparably more complicated and demands a much higher calibre of smith. In this case, the loss or waste is an issue and fusing is a must, so the whole piece must be thought out, ad nausea. 100 hours is possible herein.

To create a design in wax as a master pattern is often fraught with danger (depending on the wax carvers expertise of course) unless the design is perfected later on in another metal and a mould is made from a perfected piece – and only in circumstances where platinum casting is advisable (for best results), where the improvements are made to suit the expected results from casting.

That is, an overly heavy platinum casting can be hardened by hammer etc to befit a very high finish as the outer layers will be hardened as though they are hand wrought - to a point. This said design must be designed wirh the intention of hammering (plannishing) - hammering is only one method.

An advantage is also had in that a mould can be made ready for future casting. A mould of a perfectly finished platinum ring (i.e. not much extra weight has been added to be later reduced) is less useful as the overall shape pending casting will be reduced by volume at up to 10%.

CAD CAM designs are an exception, but that is only possible where a CAD operator knows the insides and out of model making and that generally means he/she has had a good few years behind the bench and knows the form.

If a good custom design requires a good master pattern being made then why not have a fully hand made platinum ring made instead. If you want your piece to be original, then why not have it hand made? What is custom made if it is not customised to you?

Hoping it helps,

Phillip

 

[LadyluvsLuxury]

WOW alot of interesting information to absorb!