Creating Detailed Moulds

We are a small specialist chocolate maker in Melbourne Australia. We specialise in custom moulded chocolates featuring company logos and other designs. To date we have created our moulds by engraving metal plates (similar to printing plates) and vacuum forming plastic over them. Whilst this method works reasonably well it is impossible to get the detail that some companies that also do this work (mainly in the US) achieve. They are clearly not using vacuum forming for their mould creation, however they are still able to produce moulds very economically as evidenced by the fact that they only charge US$100 for setup. I have attached a file of an image of one of the chocolates produced from the moulds they are using. I have experimented with silicone moulds, but struggle to get the gloss in the chocolate using these moulds, and the silicones I have used are quite expensive and time consuming to set. Naturally none of the companies I have approached will tell me how they achieve such great detail with an economically produced mould despite the fact that we are in AUS and they are in US. Does anyone have any ideas how these companies are able to create such great detail in a custom manufactured mould at an econimical price? Any ideas really appreciated. More examples of this type of work can be seen at example sites like www.chocolate2.com
updated by @graeme-bulluss: 05/01/15 02:50:00AM

I was just talking to an ag engineer today and he said that it helps to put high pressure on the the non-vacuum side of the mold to get better detail, e.g. with pressurized gas or a liquid. I don't know how this would work practically to keep liquid or high pressure gas on the plastic sheet for vacuum forming, but at least it's a lead.

Hi Nat,Thanks for the reply. We had previously thought this may help but no idea how to implement it on our current machinery, and having spoken to a couple of plastics people here in AUS they feel that vacuum forming of any description is not going to give us the fine detail that these companies are achieving. There has to be something else. Thanks for the hint anyway.

Graeme, did you ever figure out what they are doing? Care to share if you have?

Hi Kane,

Alas not. It's still a mystery. At the moment we are persisting with vacuum forming. We've tried a food grade silicone mix which works well but is impractical for volume usage.

The search continues.....

The only way I know of to get the detail you are looking for is to create your molds via injection-molded polycarbonate. I have never once seen a vacu-formed mold have the detail that a polycarbonate mold can produce.

Any idea then how the folks Graeme links to can do this so cheaply?