Welcome to the Onshape forum! Ask questions and join in the discussions about everything Onshape.First time visiting? Here are some places to start:
- Looking for a certain topic? Check out the categories filter or use Search (upper right).
- Need support? Ask a question to our Community Support category.
- Please submit support tickets for bugs but you can request improvements in the Product Feedback category.
- Be respectful, on topic and if you see a problem, Flag it.
If you would like to contact our Community Manager personally, feel free to send a private message or an email.
I'm guessing you're using Plain washer large grade A ISO 10673 (or normal or small). This is the table from ISO 10673 for the small size (the ID is the same for normal and large sizes as well). M5 is 4.55 mm nominal.
The reason for this is because washers from ISO 10673 are Plain washers for screw and washer assemblies, aka SEMS. I think you're actually looking for ISO 7089 or 7090. These are the more common ISO washers and have a 5.3 mm ID for the M5 size.