IRD sliding dropouts hitting chain
 

I have a Soma Wolverine 3.0 with the IRD sliding rear dropouts. The screws attaching them to the frame are hitting the chain in the smallest cog. Is it safe to put some lock washers between the screw and frame?https://cimg5.ibsrv.net/gimg/bikefor...17e375e968.jpg

You know that screws can be shortened, right?

or put a flat washer under the bolt head so it will not stick out on the back side..

washer's thickness = to how much you see sticking out , as in your picture.

Check Soma documentation, I'll wager you're missing some hardware.

Paragon Machine Works sliders for example require both a flat and a locking washer on each slider bolt....in addition to adequate torque (which for them is 25Nm per bolt).