Not quite. SCRATCHBUILDING IS BUILDING FROM SCRATCH. (duh.

)
A simple equation for scratchbuilding would be:
Time+Raw material (wood/metal/cardboard/sheet plastic)+ expertise (or lack thereof

) = Scratchbuilt Item. Usually Scratchbuilt Items are from plans found anywhere, or measured and drawn by yourself, and the purest scratchbuilt Models have a very short list of "commercial" parts, if any at all.

I've heard of some people casting their own brass detail parts, winding their own motor armatures, OF THEIR OWN DESIGN, and building a wooden cab with hand made minirature nails.
If there's a more than 50% commercial part count in your creation, and is based mainly upon an existing model(s) (Or parts there of) you have lying around, This is called KITBASHING. Once they're comfortable with KITBASHINGThis is where most people think they're ready to try SCRATCHBUILDING, and they're usually right.
There is, however a gray area.
Scratchbuilt structures are ones based off the types of plans mentioned earlier, and may include commercial doors, windows, vents, ect. BUT they still are of a unique (non-mass produced) quality. Laser woodkits, and craftsman style kits are about as close to scratchbuilding as one can get while still following instructions.
An example of excellence in scratchbuilding would be Robin M.'s much beloved buildings constructed out of old Cereal Boxes, and the new term "Cereal Board" comes from. these can be found in the GEMS section of the forum. :thumb: