Tony in SC said:
I forget the name for them but they are used on wood so something can be bolted to it. The hole in the center is threaded. A hole was bored in the wood and the cleats were pressed in the wood to keep it from turning when the bolt was screwed in. All the bass boat seats and other marine stuff used them before things were switched to plastic. You can still buy them. Tony
PS: They are called "T" nuts. Lead ones are very old, new ones are stainless steel.
Great info Tony!
fits right into the boatyard find.
I can see how they could be inserted into a hole, then fastened from the other side,
getting compressed and sealing the hole.
That looks like a very early double acting steam engine or a steam pump combo. Tony
Lead of course won't provide holding power, but may have just acted as a seal where
planking was attached to the ribs.
there is a close resemblence:
http://myword.info/definition.php?id=tee_nut_1-a
good looking avatar !
My girl came home one day saying "I found one of those old rusty things you like
out in the woods today", I think it's a two piston steam engine and boiler.