RCR40 Mk1 Body cutouts

Rod Dittmar

Supporter
What kind of tool(s) do you guys recommend to make the cutouts in the fiberglass body (ie. headlight openings, rear clip engine vent openings, etc.)? And, any DOs & DON'TS advice would also be appreciated.
Thx, Rod
 

Neil

Supporter
Rod, it really depends on what kind of cut you are making. A thin cut-off wheel is fine for straight cuts But for curves, it is another story. I frequently use a saber saw for some types of cuts. Drill a 1/4" hole at the end of each cut, add masking tape on the surface to protect the gel coat from getting scratched by the saber saw and then cut using a thin blade. For large-radius corners, I use a hole saw and then cut between them with a saber saw or an abrasive cut-off wheel. Finish each cut edge with silicon carbide abrasive paper to leave a smooth, slightly rounded edge. NEVER use sharp corners when cutting out holes in metal or in fiberglass. Those will be where cracks develop. Look up the problems with the early De Havilland Comet jet airliner.
 
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For small cutouts like the NACA ducts on the front clip a multipurpose cutting bit on the Dremel works well.
Dremel_Rotary_Tool_Bit_Cutting_Bits.jpg
 

Rod Dittmar

Supporter
OK, everyone. Thanks for the help. All tips well noted. I'll try to be careful. Regarding those NACA ducts in the front: Is anyone actually cutting those out and using them for something? Our car is going to be a street car with heat & A/C and no intention of ever racing it or having a perfect example of an original.
Rod
 

Randy V

Moderator-Admin
Staff member
Admin
Lifetime Supporter
OK, everyone. Thanks for the help. All tips well noted. I'll try to be careful. Regarding those NACA ducts in the front: Is anyone actually cutting those out and using them for something? Our car is going to be a street car with heat & A/C and no intention of ever racing it or having a perfect example of an original.
Rod

Top center duct was cut out and water trap only.
Side NACA ducts were channeled to supply fresh air to cabin. Car was sold before that was completed, but you can get an idea of where I was headed with the above link. Also the rear ducts are covered in the rear clip section of the site.
 

Brian Stewart
Supporter
All three cut out on mine. All give useful ventilation - sides to eyeball vents and centre to demister grille.
 
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