I need to tighten a couple of chainring bolts on a FSA crankset. Compact 110 BCD if it makes any difference.

I bought a CNW-2 Park tool thinking this would hold the nut. The center alignment spline is too wide on either end.

I looked on FSA's website at their tool collection and they don't offer any thing that I saw.

Any ideas?

rubber glove and hold the nut with your hand. i have never really needed a chain ring nut wrench/use it often. dont forget to grease the threads. could also mod your tool with a file but im not sure where its not fitting

A wide blade flat screwdriver can be used as a chain nut tool. You may have to thin the blade to make it fit the slot.

Thanks for the input. The bolt extended such that it was flush with the rim of the nut so a wide screw driver wouldn't do it and there wasn't enough purchase on a single side to do the job either.

The trick with the rubber gloves is good but these were factory installed and they were "tight" but spun when I tried to tighten them some more.

I ended up grinding the guide spline to a point and that did the trick.

If this is a routine problem, I suppose you could grind the center out of a wide-blade screwdriver leaving only the two outside edges in an inverted U-shape so it would stradle the bolt's center.