Problems with die cast? Brass is die cast right?

[esarratt]

I have been reading The Complete Book of Anchoring and Mooring by Earl Hinz.

Hinz does not think highly of using diecast metals for structural purposes. This is the first I have ever heard of this issue.

Your thoughts?

It appears that brass is diecast. That would rule out brass, or chromed brass, for chain stoppers/pawls and for other fittings that come under load.

Here are the quotes:
Pg 55--Diecast fittings wearing a shiny coat of chrome pose a latent danger to the boat.

Pg 59--Proper deck cleats are made of bronze or stainless steel and provided with a broad, four-bolt base to prevent tipping when under side load. Unlike running rigging cleats which get loaded from one end only, deck cleats can get loaded from any direction. You should not depend on cleats made of die castings for ground tackle use as they have little strength.

[00X]

Originally Posted by esarratt

I have been reading The Complete Book of Anchoring and Mooring by Earl Hinz.

Hinz does not think highly of using diecast metals for structural purposes. This is the first I have ever heard of this issue.

Your thoughts?

It appears that brass is diecast. That would rule out brass, or chromed brass, for chain stoppers/pawls.

Here are the quotes:
Pg 55--Diecast fittings wearing a shiny coat of chrome pose a latent danger to the boat.

Pg 59--Proper deck cleats are made of bronze or stainless steel and provided with a broad, four-bolt base to prevent tipping when under side load. Unlike running rigging cleats which get loaded from one end only, deck cleats can get loaded from any direction. You should not depend on cleats made of die castings for ground tackle use as they have little strength.

I recently read a test study done by BoatUS some time ago. It was done on cleats to failure. Cleats with four feet broke easier, the feet failing first. Cleats with with through bolts in the center were stronger in which case the fastening bolts failed first, not the cleat. The angle of load/failure was pretty random and didnt seem to favor any particular direction. Stainless was stronger than the others but Bronze and aluminum did well. I dont think any brass was tested in that study.

The takeaway was to use the largest cleat you could fit, preferably one without feet thats thru-bolted with backing plates using the largest diameter stainless bolts you could fit. Cleats with feet need to have very beefy and substantial feet.

They didnt mention anything about how the cleat was made. The article was not that in-depth.

I think the reason is that die casting creates a pourous sort of compressed mixture of metal. Iv'e seen it fail on non-boat parts on occasion. The interior of the parts looks like compressed sand. It does not look strong even to the untrained eye.