I want to upload and create a bracelet using shapeways, and I already have a autocad file for it. However, I don't know how to make sure that, when it is printed, it is the right size to actually fit on someone's wrist. Could anyone tell me how I can see and set the scale factor in my model? Much appreciated.
Make sure the bounding box of the uploaded file matches what it should be. Then in your cad software you could print it out on a 2D printer 1:1 and see what size it would be.
I depends on how you export the file, and the file type. Some file types only deal in certain units. Other file types don't specify a unit, so Shapeways will ask you which units to use when you upload the file.
You could just download NetFabb Studio Basic for free and measure the model to ensure it is the correct size before uploading (if it's the wrong size you can use NetFabb to rescale the model file to the right size too) And as Mike says, filetype and measurement units come into the mix too - the safest bet is to create in units as inches or mm for whatever software you use, check the measurements in NetFabb and then upload the model as the units you see works in NetFabb.
Yes to find out what your dimensions are, you can use Netfabb, I was thinking to compare to real world, as in would to see if the size is right to fit as a bracelet, to print it out on an inkjet to see if what's on the screen is as you imagine it.
A length of string & tape measure along with netfabb works too How many times over the last couple of years have we seen 'sizing' questions?