I have had a few questions about modeling rivets, and I thought with the new Space Ork codex release hopefully there will be some Orky building going on, so here is a quick how-to.
Some people like to use the hole punch method, but it takes forever and the PVA method is ridiculously fast.
Here is what real big rivet heads look like. I will simulate the rounded heads using surface tension and PVA glue.
I am using Games Workshop PVA glue (it was free) it is the same as Elmers white glue, just more expensive. You can also use carpenters glue (yellow stuff).
Use a toothpick for small size, I am using the back of a small paint brush for a larger size.
Squeeze a glob out and dip into it with pointy tool and dab on to the model, keep rows and spacing regular for imperial or space marine stuff, for Orks use different size dots and be more random with placement, you can go back over the dry dabs to build them up more if needed.
The glue will turn clear as it dries, and you can paint over it at that time.