thwart and seat fasteners

[ohioboater]

Anyone know where to get those strange, raised stainless washers that Dagger used on their canoe thwarts and seats? Or even what they are called? For that matter, why do they use those instead of plain old flat washers?

If you don't know what I mean, look at a Dagger open boat (I'm pretty sure my Mohwak uses these, too). Where a thwart, yoke, or seat bolts through the gunwale, there's a flathead machine screw with a raised washer that matches the cone profile of the underside of the machine screw's head. I haven't unscrewed one of those yet to see if it's more than a washer. Maybe it is. In any case, I need to mount some replacement seats and don't have the OEM hardware. Can I just use regular screws, or do those cone shaped things serve a structural purpose?

Any ideas?

[ohioboater]

Just learned that they are called finish washers, and that they can be found at boat supply places like West Marine. Guess they're designed to keep the screw head from catching on things.

[msims]

Dont know if you have Brafasco in the states, here in ottawa there's a store called "Ottawa Fastener and Supply" that certainly carry them. I'm guessing you'll be able to find them around... perhaps even at home despot? (They just bought Brafasco)

Mike.

[KNeal]

I've seen 'em at Home Depot and Lowes. Look where the specialty hardware items are located.

KNeal

[ohioboater]

Our local mom and pop has them, so I'll buy them there.

[Ed Eout]

For what it's worth department - they are Dimple Washers.
Home Depot/Lowes in the speciality bolt section.