For 3D drawing, we would prefer in STEP.IGES,STL,STP,SLDPRT format. For 2D drawing, we would prefer there are tolerances with dimensions if possible. Please put all files into one folder and compress the folder into a ZIP or RAP file before uploading(Max 10MB). Larger attachments can take a few minutes to transfer depending on your local internet speed. For attachments over 10MB, please send it to contact@chuckmetal.com