So just wrapped up this years winter project. I decided to take a crack at making my own carbon fiber front bumper cover. After getting inspired watching too many YouTube videos I decided to give it a go using the positive mold overlay method. For a one off, this eliminates the need to spend time and effort making a mold. It does, however, mean more work on the back end to get a smooth paintable part. The gelcoat look isn’t practical with this method since the outer surface will not be smooth.
The modified OEM plastic bumper weighed over 15 pounds.
I began by taping the bumper to protect the paint in case this all failed and I needed to go back to this bumper. I also wanted to smooth over gaps. I then used auto body filler to shape and smooth the area around the headlight blanks. I wanted everything to be more aero.
I then used some expanding foam where more changes were desired, like smoothing the kidneys (leaving only an outline of them for visual effect) and decreasing the lower opening.
To get a more smooth topcoat to the foam, I applied a layer of clay.
The next few steps I have no pics, but over the clay I used aluminum foil taped in place. I then sprayed the bumper with a few coats of mold release PVA. I then applied three layers of carbon fabric one at a time, first wetting the part with epoxy, letting it partially set up (about 90 minutes) and then carefully laying a layer on and working it in. This allowed the part to stick to the contours and not lift as it would if wet. This had to be down for each layer. Not a fast process.
Once that set up, I popped it off the mold (well, ok more like wrestled it off) and this is what it looked like, weighing less that 5 pounds!
To prep it for paint, I floated an aircraft body filler (Superfil), which is an epoxy like super light body filler. It looks like crap at this point, but is now smooth. As you can see, the kidneys will be clear coated for effect.
I decided to paint it myself, so I made a makeshift paint booth using my popup tent as a base and used a fan blowing air through three panel filters into the booth and had it exit out a window through more filters. Pretty cool and necessary as the outside temps weren’t cooperative for painting.
Here it is looking much better in primer flat black.
I also went ahead and painted my newly acquired Goke rear hatch. I had to modify this a bit to reinforce it for my wing mounts and I also eliminated the third brake light. A nice little 23 pound savings with this hatch!
I also needed to incorporate an intake ram air scoop feeding a 4” carbon fiber tube I made. Will be interesting to see how this works on track. I will be data logging to provide Josh (pokey britches) with data in case this necessitates a change to the tune.
I started by making a mold with foam and body filler after a lot of careful measuring and sizing up.
Finished part looks the business...
And here is the finished bumper painted a generic gloss black. Doesn’t color match, but is close enough. I was going for a 10’ paint job, so am happy with the results!
So, that was my winter project. How about y’all?