Thursday 24 January 2013

Epoxy rules, Ok?

A mail came in today from a past customer:

Hi Roy,

A couple or 3 years ago, I purchased from you whilst still in Paarden Eiland, two part epoxy (Resolution 816 with 205 curing agent). This afternoon, I
used it again as a penetrating epoxy covering for my new plywood washboards.

I measured out (with scales) 100g of epoxy and 65g of curing agent as per the attached instructions, into a glass container. After about 10mins or so,

I noticed that the glass bottle was getting warm - I considered this to be part of the curing process. But, after about 15 - 18mins, smoke started to
drift out of the glass bottle and the glass was too hot to touch directly with bare hands. After a few more minutes, the whole contents of the glass
bottle was virtually cured. The mixed epoxy that I applied to one washboard is still quite wet after about 30/40mins or so - I noted that the normal
curing time as stated on the instructions was about 3 hours.
So, has the epoxy reached a "sell-by" date that I am not aware of, or,
is this high heat produced in the mixing bottle after such a relatively short time part of the normal process for a mix? - as I'm sure that this has
not happened when I used it previously.

Your prompt response shall be appreciated,


Hello Alan,.

That is good news, it means nothings gone off!

Today I also got caught short a little, the same issue and I was in the
garage but at 30c we see things go faster, as the mix first warms up
it then heats itself and accelerates. When the air temprature is over about 27c use small mixes and
spread it out in a painters tray, out of the sun and it will be ok.

I have new stocks if you require?



Alans reply:

Thanks Roy,

Will using slightly less curing agent assist in a bit of longevity due to the heat (also in my garage with doors open)?

I emailed back right away and told Alan that epoxy does not work like a polyester resin and the mix ratios must remain as writen on the lable as a full cure depends on this.


Warning, it would be quite possible to cause a fire with too much epoxy mixed and left
to pre heat, always use it in a contolled manner and always be there when you do, once applied thinly it will be quite safe .

More info on the use of 816 epoxy can be found in the link.

Note the use of recycled milk containers! We also pack in new one and two litre packs when we are shipping, this all saves costs and the lower price is passed on to our customers.

We sell our own brands,its an issue of us buying bulk and using what we know about ourselves,it was Dudley Dix,when building his Didi 38 design for himself,that introduced me to an epoxy brand he had tested prior to building his boat.


Shell Chemicals made an epoxy called Epikure 816,this is the base for many re branded systems you will find world wide,we have left it just as Epoxy 816 for simplicity and when Shell Chemicals sold out to Resolution,we renamed it as Resolution 816 epoxy.The epoxy is no use without a hardener,we supply and use 205 cure agent, mixed in a ratio of 100 grams of epoxy to 65 grams of cure agent.