alfa 159 dash

General Composites Discussions Composites Talk
#1

http://www.autoevolution.com/images/testdrive/gallery/alfa-romeo-159-18-tbi-2010-501_3.jpg

hi guys
i have a question regarding the gray dash trim you see in the picture with the 3 air vents radio and climate control. i want to make it out of cf but i am curious to know which way would be the best way to make the holes for the vents and radio etc… should i make a flat panel and then cut the holes out once the cf is cured orrrrr make the fiberglass mold with the holes already in it and cut the cloth around the holes??? i am looking for the cleanest and most precise method since the vents and radio and climate control has to fit in itt. and do you guy have any tips for cutting the carbon cloth in precise circles and making the rectangle for the radio and aircon. thankss so muchhh

#2

Hi, personally i’d draw it in CAD and have it CNC machined by waterjet from a flat plate of CF.
But you could make the mould out of fibreglass and mould into the cut outs. Once cured pop the mould and sand down where it dips in to the holes leaving a couple of mm. This will give you a lip to work to when cutting the panel. You can then use diamond grit hole saws and files to trim it.

#3

easy first: cutting circles can be done with a diamond edge coredrill, come in all sorts of sizes. Will leave a nice clean perfect hole (and as accurately placed as long as you drill it in the right place :wink: )
You will NOT get the rounded finished edges a plastic piece will have. However, if youare willing to live with that, and just bevel the front edge of the cutout with sandpaper, you are good to go. The larger openings I would say, Dremel, cutoff wheel, diamond coated bit, and work at it slowly (maybe flat cut the sides, and coredrill the corners, then finish with sanding.)

You can also make a flat mold, BUT have the cutouts in the mold, like raised areas. Then you can even cut out the fabric where the holes are. That will require post trimming work still, but give you nice edges.

Not sure how the panel attaches to the car, but you might have to bond special inserts/clips in the panel somehow, or maybe just velcro the panel on the dash?

#4

I would make a mould from the original part and than infuse it. Than everything willl be the same than the original one.

#5

Making a mould would be easy, but the problem is all the mounting stuff, stiffeners, clips, etc that is behind it. It is virtually impossible to copy that.

If it is a one-off, I would either have things CNC-d from flat sheet. With a bit of care and some MS Polymer to bond things, you can get a nice fascia glued to the original part. I would definately make a glassfiber piece first to test fit. You will inevitably need to adjust your drawing to make things spot-on.
In that case you will have to live with the fact that it is only the front, and not the sides that have CF.

The other option involves more work:
-make a mould from the existing piece
-make a carbon fiber piece from that mould (1 layer of CF, then a layer of black resin, so it does not shine through).
-grind back the original part so it fits in the carbon part
-glue the 2 together (in the mould, and probably using vacuum) (assuming the original is ABS, and can be glued)
-trim, and install in the car. You have all original mountings.

#6

Thanks for all the great suggestions.
I think I am going to overlay cf over the existing abs part so as to avoid the whole issue of having to make mounting clips, etc. To compensate for the thickness of the cf around gauges I will place dry cloth around the apertures and use a dremel or sand paper to make those apertures a bit bigger to accommodate the cf and resin that will eventually be placed in around them.
If you guys have any suggestions regarding what could be used to widen those hole I would again greatly appreciate it.
Anyways this is going to be more of a test piece for my vehicle to get an idea what look it would give the interior. AGAIN THANKS to everyone.