My question is, sketchup will be slowest and more bug splat with I do that? because my my maind hard disk is almost full so Im having to save the files and components in disk D.
A full system disk (the one where your OS is installed) will cause problems with all applications sooner or later, as the system runs out of temp space.
If Disk D is not an USB memory stick you should be OK. Problems are mainly with saving directly to remote cloud storage services like Google drive or Dropbox or folders that are synced to them.
How much of free space would you recommend?
.I don’t have a clear answer, but see, for instance, this:
I didnt find the answer but I guess 20gb would be a nice amount? for a 250 GB SSD disk
I have a smallish SSD disk and a larger traditional hard disk and I have switched all my storage to the larger drive, leaving the SSD solely for the OS and installed applications.
I prefer about 50% free space, my C drive is a 500G.
but i think its better to use the file you are working on in the same ssd disk right? since ssd memory is faster, no?
Yes, it’s faster but with my file sizes, saving times aren’t a problem. Whatever the disk, it’s only seconds.
I have used a folder on a secondary drive to store all SketchUp models for years and have never had any problems.
So long as it is a permanently mounted drive, I don’t think SketchUp cares which you use for skp files. As has been stated, though, any sort of removable or remote drive is vulnerable to file corruption if network events such as sync overlap SketchUp’s save cycle. Timing is the issue, so you can go quite a while before disaster strikes.