CPES and Weight

[albacore471]

Albacore 471 is a 1958 mahogany ply boat built by fairey marine. I plan to race the boat again, after a few more minor repairs. I like the idea of CPES as a base coat on the hull but I am concerned about weight. I am estimating 15 pounds added and that would be too much, is my estimate wrong? Are the benefits that great? I would like the boat to be around quite a while longer.

[Peter Malcolm Jardine]

Unless I am really off, it would be nowhere near that. The next benefit would be sealing the ply with CPES would give you longer life to the varnish, and less water absorption... less weight.

You might be doing the calculation based on the weight of CPES in liquid form. Remember, the solvents evaporate. The remaining weight is negligible

[ 11-29-2005, 07:02 PM: Message edited by: Peter Malcolm Jardine ]

[Concordia..41]

At 15 feet in length and 240 pounds hull weight, the Albacore is a great first boat for those who are just learning to sail and a very competitive racer for more advanced sailors. My initial response was that even if your 15 lb calculation was correct, 15 lbs added shouldn't be a big deal, but that works out to a potential weight increase of 6.25% so I'll let one of the "learned ones" respond.

Edited to add PMJ is correct about factoring into your calculation the solvent portion of the liquid, which evaporates.

[ 11-29-2005, 07:07 PM: Message edited by: Concordia..41 ]

[Don Z.]

Where is the 15 pound estimate coming from?

To get a better estimate, weigh a piece of mahogany veneer, perhaps one square foot or so... eighth inch thick should be OK, I doubt that CPES will soak deeper than that.

Then, apply, let cure, re-weigh. Multiply the difference by the amount of square feet you'd be varnishing.

Just for giggles, do the same with a few coats of varnish or paint. At some point, you may find that CPES weighs less than a coat or two of your finish. There's a thought. Instead of 10 coats of varnish, CPES and seven coats... or...

I really do think the weight would be negligible.

[Ian McColgin]

You're sealing and finishing the boat in any event. Ounce for ounce the CPES will do a better job in that role and is lighter than any other sealer I've used.

[Dan McCosh]

The 15 lbs.would be about two gallons of CPES. That sounds high.

[Frank Wentzel]

According to members who have weighted the remaining portion after evaporation of the solvent CPES is 70% solvent and 30% non-volitile epoxy. So if you put on 15 pounds of CPES, after solvent evaporation is complete you will have added only 4.5 pounds to the boat.

/// Frank ///

[P.I. Stazzer-Newt]

Are you sure about the mahogany - at that time Fairey was using a lot of Agba - the hulls have a fabulous reputation for rot resistance.