Right Materials, Best Tools, Good People

Let’s talk about fiberglass and what we’ve learned in more than ten years making composite parts.  Since 1994 we’ve built and shipped more than 6,000 body shells, over 25,000 body panels and designed and built over 100 complex molds and tools.

The way we use fiberglass in making replica bodies is completely different than most kit car companies, and not at all like the classic kit car of fiberglass plopped on top of a flat ladder frame.

The average weight of a fiberglass replica body (just about every single kit out there) can exceed 700 lbs.!  The reason for all this weight is the fiberglass is commonly used as a major part of the structure and interior. 

By using fiberglass for the exterior body shell and panels only, we removed the stress and significantly reduced the weight while maintaining rigidity with the underlying matrix of ¾” steel tubing and aluminum panels (the right material for the job).  The result is a body that weighs in under 200 lbs., yet is strong and rigid.  Also, the FFR body shell is much more resistant to stress cracking due to its non-stressed mounting design and correct gel coat thickness (heavy gel coat can lead to “spider cracks” since there is no strengthening fibers). 

Is our car lighter because of a thinner body shell?  No.  The body laminate schedule is a common thickness (3/16” nom.) for hand-laid composite body shells.  The weight savings comes from the use of aluminum instead of fiberglass in the cockpit, footbox, trunk and wheel well areas. 

The body specifications are quite simple.  Our body incorporates approximately 110 sq. ft. of surface area and weighs about 190 lbs. total.  Our aluminum chassis panels weigh in at bout 75 pounds total.  Kit cars using fiberglass tubs (cockpit) and/or wheel wells and trunk/engine bay liners have about 100 sq. ft. of additional fiberglass.  This would account for an increase in overall weight of about 200 pounds (providing the lamination was the same), but more commonly adds about 350 lbs. to the vehicle weight since the cockpit is usually thicker as it’s being used for structure.  To make matters a bit worse, companies that use “chopper gun” fiberglass have a hard time controlling laminate thickness and can end up with even heavier parts!  

Manufacturing

From our very first molds in 1995, we have learned a great deal about the tools that molded parts need to be made right.  The quality of the part you get comes down to three simple things… 1) The quality of the raw material (resins/cloth),  2) The quality of the tooling (molds, trimming equipment, etc), and 3) The skill of the people who actually lay-up, cure, and trim the parts. 

To control our quality, we design, build and own all of our own tooling.  We use an Eastman M9000 CNC cloth cutting machine to ensure consistency of all composite fabrics and patterns.  Our 10 man molding department uses only hand-laid processes for every single part, and molded parts are trimmed on our RPT Technologies robotic trimming machine. 

Our molding technologies have grown tremendously over the years.  Today we put as much QC work into our fiberglass parts as we do our steel frames.  You’ll notice that the parts carry control numbers that correspond to the date of manufacture, mold number, and molding department member who made the part.

You can count on us to deliver a part that is engineered to be the correct strength and fits right.  The FFR Mk4 body shells are shipped assembled to the frame.  The parts are unfinished (taken right out of the mold and require bodywork).  Recently we changed our process from molded edges on panels to a high speed router trimming method.  This eliminated air voids on tight radius areas and enabled us to make the parts match the openings better (the panels are actually made too big, enabling you to make really tight gaps on all hoods, doors and trunks).