headlight covers

[Tom]

Guys,

I've researched some of the threads on installing headlight covers, and I'm hoping for a digest of the the most effective/best looking retention methods.

I'm building a Lola T70 replica, the covers are fairly beefy poly carbonate. My first plan is to paint the borders on the back side with black paint of some description (any advice?).

When doing so, do you just lay contact paper on the back side and then lightly cut a line with an exacto knife to allow peeling the border?

Second, are there drawbacks of mounting with cap screws vs. rivets vs. gluing with RTV silicon? I don't know how I would like to capture nuts on the body shell if I go with screws, and if I go for rivets, I'm a little concerned about stressing the fiberglass. If I go with glue, then cleaning the inside of the covers becomes a bit of an issue.

Finally, I assume people are using some kind of foam gasket between the shell and the cover.

TIA.

Tom

 

[Seymour Snerd]

I don't know how I would like to capture nuts on the body shell if I go with screws

I have used rivet nuts like these: McMaster-Carr in the fiberglass doors of my SPF GT-40 to retain the windows. Of course one needs to be sensitive to the reaction of the body material to the expansion of the rivet since the rivets are presumably intended to be used in sheet metal.

The ones McMaster supplied were manufactured by AVK: AVK Industrial Products, AT series if I remember correctly.

 

[Jack]

Not a T70, but for my SL-C I had intended to paint a border, use a foam tape and nylon screws into rivnuts in the flanges. Changed my mind! I'll now have NO BORDER paint or foam tape and will secure with the rivnuts & black nylon screws. This is because of my chosen color scheme (silver with black CF accents). Have a look at the Sauber Mercedes C9. If concerned about the flanges cracking, they can be built up a little with some fiberglass on the backside. I've had no problems so far. Drill your headlight covers slightly larger than the nylon screw to allow for some differential expansion of the different materials. McMaster Carr has everything you need.

 

[Mark Clapp]

Tom, I installed heli-coils into the body. I too wanted to be able to take the pieces on and off easily for cleaning, etc. The coils do not stress the body and are invisible since they can be installed to just below the surface of the body. I used 6/32 stainless machine thread screws. You can buy an installation kit from McMaster Carr, which has the drill bit, tap, and insertion tool as well as several of the coils. I went with 0.173" length coils. There is no need for thread lock as mine have not come loose in almost 10 years.

 

[Mark Worthington]

I also used helicoils (8-32) and I ordered stainless steel flat undercut head machine screws. I countersunk the lexan covers and the screw heads are flush with the covers for a clean installation.

 

[Terry Oxandale]

Helicoils X 3! Works great in fiberglass (provided some material buildup is done on the backside) and I've actually used these to hold entire body panels in place.

 

[Jack]

You guy's have me thinking now. It never occured to me to use helicoils. Perfect solution! Will still use the nylon screws though.