Glyn
I'm assuming you're taking about the range of 200's shown below (copied from the Badger web site). After looking at the instructions more closely it appears the biggest difference is in the spray head design. The bottom one is obviously a permanent gravity feed. Depending on the head design they will handle a certain range and type of paints. The gravity feed model is designed for very fine work as opposed to the others.
About using these on large surfaces, I painted the hull on my Graupner Seabex with the one of these Badger 200's with no problem. Gave a very nice finish with a laquer paint designed for model work. The model designed paints have a much smaller pigment than paints designed for things int eh 12" to the foot world and are, therefore, much easier to pass through a small airbrush nozzle properly.
John
BADGER® 200®
SINGLE ACTION, INTERNAL MIX SERIES
Badger's 200® Series offers the ease of single action operation while providing the fine spray pattern of internal mix paint atomization for professional results. Depressing the trigger releases a pre-set amount of color which can be regulated by turning a needle adjustment screw at the back of the airbrush handle. Once the desired paint flow is set the airbrush will maintain the preset spray pattern until the user chooses to change it.
MODEL 200 BOTTOM FEED AIRBRUSH
Simplicity of use makes this the top choice for the advanced model painter or decorative stenciler. Also an excellent airbrush for painting posters, auto detailing and ceramics. The Model 200 will spray inks, dyes, watercolors, gouaches, properly reduced acrylics, fabric paints, modeling paints, automotive lacquers and enamels, most ceramic stains and glazes, Air-Tex®, Air-Opaqueª and MODELflex® airbrush colors. (Available in a single head design or detail design).
FEATURES • Choice of 3/4 oz. (22ml), 2 oz. (60ml), or 3 oz. (90ml) paint jars, and 1/4 oz. (7ml) free- standing color cup (Bottom feed only)
• Color cup and one-piece jar adaptor taper-fit for quick color change (Bottom feed only)
• Self-lubricating PTFE needle bearing enables continuous proper paint flow and prevents needle wear
• PTFE head seal assures efficient air flow
• Non-slip, one-piece trigger
• Fine (F) - pencil line to 2" (51mm) spray pattern
• Medium (M) - 1/32" (0.8mm) to 2 1/2" (63mm) spray pattern
MODEL 200 DETAIL AIRBRUSH
The finest single action internal mix detail airbrush ever. The Model 200-20 is designed with the PPS paint flow adjusting system, enabling recurring accuracy in spray pattern and line control.
MODEL 200 GRAVITY FEED AIRBRUSH
Offers single action simplicity in a gravity feed airbrush. Allows for "close in" CLICK IMAGE TO VIEW INSTRUCTION BOOK
spraying. Excellent for model detailing and fingernail artists utilizing mini-stencils. (Available as Fine and/or Medium).