[Jerry O]

Just getting ready to set body on chassis when I noticed, while looking upward, several areas at, or near, the fender seams, spots of light shining through from the overhead garage lamp. Seems to me, if I were to start grinding away in order to prepare the seams for filling, I might poke holes through the fenders. If this is common, (3.1 Roadster) might I be advised to apply 1 or 2 layers of fiberglass strips from underneath to prevent this from happening? If so, what preparation must I go through before performing this procedure? I already have the body on it's back and am wondering if I should scrub the areas with a cleaner beforehand? :confused1:

 

[kiki231]

i will tell you that my coupe (gen 2) had a similar trait. I noticed that light was shining through the seems in some areas, and i thought that the mating process had fallen short-- turns out that it is simply an area with no gel coat and little mat-- the resin all by itself is quite translucent. One of my seems runs to an edge where i was able to see how thick it really is -- even though i can see light thru it. i would bet your seems are fine.

 

[CDXXVII]

I had the same concern with my Mk4. I had my brother over and he stated the exact same thing. Light shines through were the gel coat is missing but the glass is just as thick as anywhere else.

i will tell you that my coupe (gen 2) had a similar trait. I noticed that light was shining through the seems in some areas, and i thought that the mating process had fallen short-- turns out that it is simply an area with no gel coat and little mat-- the resin all by itself is quite translucent. One of my seems runs to an edge where i was able to see how thick it really is -- even though i can see light thru it. i would bet your seems are fine.

 

[edwardb]

It's likely not a problem. In fact, shining a light from the back is a recommended way to confirm there is no gel coat in these areas. You should see a continuous line once the flashing is ground down. Good explanation and pictures in this recent thread:

http://www.ffcars.com/forums/17-factory-five-roadsters/295726-another-body-seam-question.html

Both the question and the first response call these "seams" and suggest these are areas that are somehow joined together. If so, that's incorrect. A better description is "parting lines" meaning these are areas where the various mold pieces are joined together during the fiberglass lay up process. The body is one continuous lay up. There are no seams in the sense of joints or areas where pieces are joined together. Adding additional layers of glass on the backside of the parting lines adds no more strength than adding glass anywhere else.

 

[JKleiner]

Edward linked my photos above so I won't do it again here. Yes, fiberglass is translucent so you will see light through it if the gelcoat is thin or missing.

Thanks to Edward for bringing up one of my pet peeves---"body seams". These bodies are one piece, there are no seams. The molds have seams, the bodies have parting lines where the molds meet (obviously poorly sometimes ).

Good luck Jerry!

Jeff

 

[kiki231]

Good point on the "lines" , lads
i stand corrected

 

[Jerry O]

Thin seams response

Thank you all for easing my mind and saving me from doing unnecessary work. I can now apply the bed liner and plop the body onto the chassis and continue on with fitting doors, trunk lid and hood.:001_smile: