"Old" Epoxy

[Ruud]

Hello,

I am new here and going to build a 14 ft stich and glue sailboat.I got hold of about 60 kilos of Epoxy (for free) that is about 6 to 8 years old it is Japanese (EPICLON 857 is the only readable for me on the cans) it has a 3 to 1 mixing ratio.

So my question can I use this epoxy for boat building? Or is it to old? Is there an easy way to test this?

Thanks in advance

[NormMessinger]

Wellll.... What I was told by a fellow that should know, Burt Rutan if I recall correctly is to mix up a batch, let it cure in the cup, then give it the scratch test. Draw the end of a file or blade across the surface. If its hard and scratches leaving a nice white trail the goop is still good. If there is any cloudyness or crystalization in the resin you can clear it up with a hot water bath.

[Bruce Hooke]

I would be careful if you don't know anything about the original "design" of the epoxy (what it was designed to be used for). The properties of epoxy can vary a lot depending on what it was formulated to do. For example, do you even know if this epoxy was formulated for use with wood? If not it could be that it won't bond very well with wood. Be a bit careful as well if you don't have any safety information because various nasty things could have been added to the epoxy to make it do something special.

One option would be to use this epoxy for coating and use new boatbuilding epoxy for bonding and other structural purposes (which could include structural glass cloth overlays). The demands on epoxy that is just a coating are much lower and the consequences of failure are also much less dramatic.

If you want to use this epoxy the first thing to do is run some tests and find out if the basic working properties seem decent.

[George Roberts]

Ruud ---

Some epoxy needs higher temps to cure than wood is comfortable with.

[Steve Lansdowne]

If you do use it to build a boat, that's a good name for the vessel.

[AndyFarquhar]

If your epoxy resin hardens up, put in in a double boiler (not SHMBO's good double boiler!) and heat it up. Sometimes it takes a lot of heat to make it liquid again.

Another useful kitchen gadget is the flour sifter - used to make wood flour. Again, do not use SHMBO's good flour sifter!

Regards

Andy

[Frank Wentzel]

I have some epoxy that is over 20 years old that still works just fine. As long as it does not have excessive exposure to air epoxy resin seems to last and last. This is not true of some of the curing agents, so you will have to test. But, if the epoxy cures normally - that is in the usual amount of time you will be alright.

/// Frank ///

[riverboathank]

Ruud, congratulations on starting a wooden boat. As to your old epoxy, a test batch is certainly recommended, also a computer search should find you specs for your Epiclon 857. As to your 60 kilo quantity, (approx 20 US gal.?), way to much for a 14' boat, send me your excess. Oh, Austria? well good luck. Hank

[Russell Sova]

Ruud, you should not use this epoxy. Instead, you should send it immediately to me.