Cedric
Apologies for the late reply.
I've been going flat out for the last 2 weeks. Our CNC programmer did a runner on us going into our busiest period of the year, so I've been heading up the design office and programming all of our CNC machinery (4X CNC routers, 3X CNC milling machines, 1X CNC lathe and 1X CNC laser machine) for the last 2 weeks, so it's been....interesting to say the least
I haven't had time to sit and concentrate on anything else.
I've been having some serious Patrol Forum withdrawal symptoms
Back on topic :
I don't really get that involved with our pattern shop to know all of the products and going on's, simply because of time constraints, but I've picked up my fair share of knowledge and what does & doesn't work over the years.
The majority of molds we make are from "F16 aluminium tooling compound" (epoxy resin base with aluminium powder and a special catalyst - can't remember exactly what it is though).
The stuff is heavy and hard as hell. The main reason for using this is for it's heat resistance, because they are used in our vacuum thermoforming process.
We manufacture heavy gauge plastic returnable interlayers and packaging for the motor industry to be used line side in production or for export to and from OEM suppliers.
They can be for things as small as the chrome button on your handbrake right up to complete engines, etc. and they are 99% stackable and collapsible for transport. So as you would imagine the molds can become unbelievably complex. Typical machine time for a large mold can be upwards of 10 hours. One I did in 2014 ran for 83 hours
A single mold typically has a duty life cycle of 250 000 parts before refurbishment or remolding.
With all that background info in mind, the main thing to remember when designing molds is they must have taper to the shape for a single direction of delaminating to make things easy on you and the mold.
I don't see why you can't make the console in a single part. It would save you time and 'goon ache' when churning out multiple parts.
From what I can see on the pics, it seems like there is sufficient taper on the sides. The front face looks as if it has an 'undercut' face (tilted forward) that could cause a few issues when delaminating, but not the end of the world. To overcome that, you will simply have to delaminate by removing the part towards the rear (windscreen direction of part), so basically slide it out backwards. Just be sure to add taper to the lip so it's not at 90 degrees to the face so the surface tension can be easily broken when delaminating the part.
You could always put a taper on the front face to simplify issues, maybe follow the shape of the dash as it curves upwards towards the air vents. The lip will still have it's fair share of quirks, but it does look cool on the console.
We've tried all sorts of different substrates for prototyping and then cloning into a mold. We've tried all sorts of foams and we've just started testing a special poured substance that looks like plaster but is some sort of ceramic compound.
The best thing we ever tried and we've used it for 20+ years now for our tooling is good old MDF/Supawood and body filler. Cheap, easy to work and works really well with fibreglass process.
We laminate layers of supawood and shape it by hand or on the CNC machines from 3D CAD models and then add details with body filler.
We generally give the prototype mold a few good coats of a polyacrethane paint and run trial parts off of it, and once we're happy we clone it and make our F16 tooling resin mold for production. You can use a sanding sealer to substitute the polyacrethane because it's damn expensive and not required for your process.
The cloning process involves the mold/plug being waxed with RAM wax and then coated with PVA release agent. Then gel coat and 6-8 layers of fibreglass.
The negative is then delaminated, sanded with water paper and polished.
The it's waxed, coated with release agent, and tooling resin process begins to create the final mold.
The same principles will apply to your part.
Clone the prototype and it will become the negative mold you will build your consoles from, so you'll basically build them upside down and inside out sort of thing. Gel coat first and then work inwards.
Have you looked at how you plan to attach the console to the dash ?
Mechanically fixed or blended to dash ? You can laminate threaded inserts into the console during the manufacture process.
You can add a texture to the final part by doing an embossing process to the negative to add the surface texture desired in the final part.
You can achieve the texture finish by draping a textured cloth/material over the plug that will be cloned to the negative.
I'll make an effort to go spend some time with our head pattern maker tomorrow and show him the pics for his opinion.
I wanted to do a decent sketch or quick 3D model for illustration purposes, but to be honest, I'm just too tired and gatvol to make the effort right now. So I apologize in advance
I'm too lazy to go find my technical pen set and graph paper, so the back of a statement and my daughter's blunt brown pencil is all I can muster at this point. Never mind the fact that I'm a lefty to make matters worse
You need to ensure the leading edges of the lip are tapered slightly and a slight radius added to avoid any fouling when delaminating the part.
Hope this all helps.