Silicone Injection Molding (gutter; overflow well)
Hi folks. Im new to the sub and looking for advice if any can be given.
Im a young industrial designer and for the last year Ive been designing, prototyping, and producing a small silicone product for our med device start up. One thing that is always annoying is the flash. My best method right now is to go along the edges of the part with a knife, but it can be time consuming and often it can leave unwanted marks, cuts, and etc, causing for an imperfect part.
My molds are 3d printed in FDM (though SLA is also on the table with inhibition precautions). For the last few months I have been trying to create a "gutter" or an "overflow well" (or valley) along the part perimeter to stop using the knife. Unfortunately the only benefit I have added to the mold design is being able to grab the flash easier. I know the nature of FDM printing also creates inconsistency to the mating faces and in turn the flashing itself. This is where I think SLA would work much better (though imperfectly) considering its resolution.
My leading concern is how to design this gutter or valley. Ive been looking and testing myself by offsetting my cylindrical gutter at .1-.2mm away from the cavity but nothing has really stuck yet. I have wondered if I should be putting it closer, or further; maybe even adding an intentional gap right next to the cavity. Im even considering a triangular geometry with one point converging at the cavity perimeter. None of these strategies are trivial in CAD so for the sake of time Im looking for advice.
Im not really even sure what questions to ask here so Im just going to post and hope to have a discussion with someone much more familiar with the process or maybe direct me to a more appropriate sub. Thanks so much for your time and I hope this isnt too difficult of a problem to discuss on reddit.
PS. My understanding of mold terminology is limited so please bear with me.