Reusing tf2 model textures

[MrAlBobo]

So...basically ive heard somewhere on the forum thats its a good idea to use model textures that are already in the game to cut down on file size...now my question is...how?
Like...how do i tell xsi what texture to use, then when using it in the game, how do i tell the model to use that already present texture...

also...after going through all the tutorials and other crap like that...its occurred to me ...I have absolutely no idea what i need to model <_< so if anyone has a somewhat simple request ill take a shot at it...

[FaTony]

U mean make a new prop, but use default tf2 textures on it?

[MrAlBobo]

yes, and without bloating the filesize by needing to zip in the texture again

[VelvetFistIronGlove]

So...basically ive heard somewhere on the forum thats its a good idea to use model textures that are already in the game to cut down on file size...now my question is...how?
Like...how do i tell xsi what texture to use, then when using it in the game, how do i tell the model to use that already present texture...

Export the VTF for the texture you're interested in to a TGA or BMP using GCFScape/VTFEdit. Use that as the texture map in XSI. Then after exporting, when you compile your model, make sure your QC has the appropriate $cdmaterials setting, e.g. $cdmaterials "models/props_farm" if the texture was from a prop in props_farm.