mindymogul
Mistress of Destruction
As some of you know I owned a Auto Body shop that did a bit more than just pretty fenders and spit shine chromies. However, I also build/modify go karts as part of the same business, as wells at motorcycles and trailers. Here's a few pointers of how to make your toys a lil' more streamline...
1~ Prepping for Body Building:
In the career field, the basics of body work include Hammer and Dollies, Drill + Bits, Sawzall, Die grinder (or angle grinder), death wheels, and preferably a welder. Those are the most used hand tools. Now for the actual construction it depends on the material you're working with. Be it Aluminum, Steel, Fiberglass, or Plastic. (Carbon fiber is too pricey to slap on a go kart. Shush). For durability and off-road 18ga sheet steel is used. For lightweight and streamline Fiberglass or 20/22ga aluminum sheeting is used. In the long run the latter is the more pricey since a 2x2 sheet is usually $25-$40 depending on your local supplier. Fiberglass is no more than $30 for enough mat and resin to cover a 4x6 section. If you were to use sheet steel 18ga would be used for skid plates and floors while 20/22ga would plenty suffice for body panels and heat shields. Only thing you'll have to deal with is rust and weight.
2~ Material Selection For Application:
All in all it's a matter of personal preference of what to use for construction materials for body panels. How I personally do things is I use Sheet Steel for the floorboards, swing arm shields, and front skid plate(s). This way I can climb over rough terrain with no worries of buckling or damaging the frame itself. I would not recommend using plastic for body panels as it can't take a direct hit and withers over time (Plus the fact it looks horrible after a few weeks in the sun and fading never goes away with it). Now for behind-seat heat shields, front frame/cockpit panels, and roof panels I'd say that 20-22ga aluminum would be your best bet. Its lightweight, can take a considerable amount of abuse before extreme damage occurs, and very easy to work with when damaged. 22ga stainless steel sheeting is also a great alternative since you rarely have to worry about corrosion and it's extremely lightweight as well. Only thing is it dents very easily and tends to amplify vibrations form the engine.
3~ Forming Of Panels and Mounting (Universal):
For Sheetmetal:
A) This all depends on size and shape of your tube. I'll give a quick guide on measurements. For odd angles take your panel blank and trace along the edge of the frame section you want to cover. For corners, cut out a notch at the beginning and end of the bend and cut along the centerline of the corner. This makes it look very professional.
Round Tube: Measure Outside width of section and add 1/4" each side to it for 3/4" tube, and 3/4" each side for 1" tube. This way the panels always meet just beyond the center of the tube. Bend metal so it conforms to the pipe evenly.
Square Tube: Measure outside with of section and take off 1/8" each side ONLY IF YOU ARE WELDING. This compensates for with of bead to match to outside of frame rail. if you are using zip-ties/pipe straps just measure to make the panel flush against the edge of the frame rail.
B) Now I'll explain the techniques for different mounting methods:
Welding: After you follow Tip A attach the panel using magnets (if your frame is steel) and form the edges to your frame rail shape. For the best results stitch weld (2" bead, 4"-6" space) the panel to the frame. Welding the entirety of the panel edge is completely up to you. This just makes it look more uniform and less costly.
Body Straps (R-Type Clamps): For this method conform the panel to your frame then remove. Mark on the curved edges where you want your strap to fit then notch out that area to ensure tight bond between frame and panel. You want to apply a bead of clear silicone or caulking on the very edge of the curve to reduce vibration.
For Fiberglass:
Take a piece of cardboard or project foamboard, trace, and cut it the shape of your frame section. You want to get as close to the outside edge to compensate for smoothing the edges later on. (If you plan on making the panel permanent cut the base material so it fits in between the rails of the frame section.) For this next step (Use the peel away side of the foamboard as it detaches. Makes things so much easier) Lay it the fiberglass mat across the panel base, making sure to slightly overlap to ensure strong a bond between layers, press the resin into the fiberglass, then repeat until you have a layer 1/4" thick. After letting it cure, sand the edges to conform to the shape of the frame rails, remove, scuff the surface of the frame rail, then lay a bead of silicone adhesive and apply the body panel.
(If you want to wrap the nose of your frame follow the 1st few steps of this section for the sides, but do it all at the same time. This way everything comes out the same and you won't get seams.)
This is just a quip of what's involved in a build. This is how I've done things for years and so far it turns out pretty well.
1~ Prepping for Body Building:
In the career field, the basics of body work include Hammer and Dollies, Drill + Bits, Sawzall, Die grinder (or angle grinder), death wheels, and preferably a welder. Those are the most used hand tools. Now for the actual construction it depends on the material you're working with. Be it Aluminum, Steel, Fiberglass, or Plastic. (Carbon fiber is too pricey to slap on a go kart. Shush). For durability and off-road 18ga sheet steel is used. For lightweight and streamline Fiberglass or 20/22ga aluminum sheeting is used. In the long run the latter is the more pricey since a 2x2 sheet is usually $25-$40 depending on your local supplier. Fiberglass is no more than $30 for enough mat and resin to cover a 4x6 section. If you were to use sheet steel 18ga would be used for skid plates and floors while 20/22ga would plenty suffice for body panels and heat shields. Only thing you'll have to deal with is rust and weight.
2~ Material Selection For Application:
All in all it's a matter of personal preference of what to use for construction materials for body panels. How I personally do things is I use Sheet Steel for the floorboards, swing arm shields, and front skid plate(s). This way I can climb over rough terrain with no worries of buckling or damaging the frame itself. I would not recommend using plastic for body panels as it can't take a direct hit and withers over time (Plus the fact it looks horrible after a few weeks in the sun and fading never goes away with it). Now for behind-seat heat shields, front frame/cockpit panels, and roof panels I'd say that 20-22ga aluminum would be your best bet. Its lightweight, can take a considerable amount of abuse before extreme damage occurs, and very easy to work with when damaged. 22ga stainless steel sheeting is also a great alternative since you rarely have to worry about corrosion and it's extremely lightweight as well. Only thing is it dents very easily and tends to amplify vibrations form the engine.
3~ Forming Of Panels and Mounting (Universal):
For Sheetmetal:
A) This all depends on size and shape of your tube. I'll give a quick guide on measurements. For odd angles take your panel blank and trace along the edge of the frame section you want to cover. For corners, cut out a notch at the beginning and end of the bend and cut along the centerline of the corner. This makes it look very professional.
Round Tube: Measure Outside width of section and add 1/4" each side to it for 3/4" tube, and 3/4" each side for 1" tube. This way the panels always meet just beyond the center of the tube. Bend metal so it conforms to the pipe evenly.
Square Tube: Measure outside with of section and take off 1/8" each side ONLY IF YOU ARE WELDING. This compensates for with of bead to match to outside of frame rail. if you are using zip-ties/pipe straps just measure to make the panel flush against the edge of the frame rail.
B) Now I'll explain the techniques for different mounting methods:
Welding: After you follow Tip A attach the panel using magnets (if your frame is steel) and form the edges to your frame rail shape. For the best results stitch weld (2" bead, 4"-6" space) the panel to the frame. Welding the entirety of the panel edge is completely up to you. This just makes it look more uniform and less costly.
Body Straps (R-Type Clamps): For this method conform the panel to your frame then remove. Mark on the curved edges where you want your strap to fit then notch out that area to ensure tight bond between frame and panel. You want to apply a bead of clear silicone or caulking on the very edge of the curve to reduce vibration.
For Fiberglass:
Take a piece of cardboard or project foamboard, trace, and cut it the shape of your frame section. You want to get as close to the outside edge to compensate for smoothing the edges later on. (If you plan on making the panel permanent cut the base material so it fits in between the rails of the frame section.) For this next step (Use the peel away side of the foamboard as it detaches. Makes things so much easier) Lay it the fiberglass mat across the panel base, making sure to slightly overlap to ensure strong a bond between layers, press the resin into the fiberglass, then repeat until you have a layer 1/4" thick. After letting it cure, sand the edges to conform to the shape of the frame rails, remove, scuff the surface of the frame rail, then lay a bead of silicone adhesive and apply the body panel.
(If you want to wrap the nose of your frame follow the 1st few steps of this section for the sides, but do it all at the same time. This way everything comes out the same and you won't get seams.)
This is just a quip of what's involved in a build. This is how I've done things for years and so far it turns out pretty well.
