What type of epoxy
We NEVER use the epoxy from the hardware that has two parts that look like putty. This is the wrong epoxy to use.
The epoxy we use has two LIQUID parts.
We mix as much as we need to do the process underway. DO NOT mix all the epoxy and hardener!!!! If you do this it will all be a hard smoking mess in 15 minutes and you will have nothing to build your boat with!
When the two liquids are mixed CORRECTLY they can be used for coating timber to protect it and to laminate fibreglass to part of the boat.
We add a powder modifier to the CORRECTLY mixed epoxy it stiffens up the mix into a glue that can be applied to surface. Typical powder modifiers are wood flour (very fine sawdust that looks like cooking flour – COOKING FLOUR DOES NOT WORK. Or we use colloidal or fumed silica, sometimes sold as “stopsag”.
We normally mix it to something between a honey and peanut butter consistency.
Epoxy Mix Ratios
Each manufacturer has different ratios for mixing epoxy. Using the wrong ratio will mean the epoxy will not go hard and the boat will not be strong.
Note that there are DIFFERENT RATIOS for mixing using weight and mixing using volume.
Make SURE you are using the correct ratio.
IMPORTANT – Read how to mix the epoxy. Mistakes mean the epoxy will not harden
Measuring and mixing epoxy is the MOST IMPORTANT job when building an Oz Goose using plywood and epoxy.
If the epoxy does not go hard then the builder has made one of three mistakes.
1/ He/she did not weigh or measure the epoxy accurately enough.
2/ He/she did not stir the epoxy for long enough or scrape the bottom and side of the mixing container with the mixing stick
3/ He/she is using the wrong mixing ratios for the brand of epoxy being used.
Why we use epoxy
Epoxy is the secret that solves the wooden boat maintenance problem.
It is also an excellent gap filling glue so it forgives small and even medium gaps in the building process.
Epoxy also does not need high clamping pressure.
Other glues require careful fits with no gaps and lots of clamps to provide enough pressure on the joint. Also they do not protect the timber at all.
Electronic scale
We used to measure by volume. But we have found that cheap electronic scales are excellent.
Couple of tricks.
Check the scale is accurate
– put 10 coins of the same type on the scale. Note the weight.
Put 20 coins of the same type on the scale. The weight of the 20 coins should be double the weight of 10 coins.
I had one scale that was a long way out. I gave the scale a good squeeze to compress it the maximum amount and then released. After that it was accurate.
Keep the Scale Clean with this Cool trick
Put it in a plastic bag! Replace the bag when it gets too messy. The bag must not be tight on the scale or it will make the measuring inaccurate.