And the goose of the week award goes to ...

[daddles]

And the goose of the week award goes to ...
Me.

You see, I've been doing a boat building course as well as building my little pram. Well, today I plucked up the nerve to mix some epoxy ... for the first time.

You know what's coming don't you.

On the course, we're using a brand that comes with pumps that measure out the correct ratio - one pump of each gives the correct mix.

You know what's coming don't you.

I'm using a different brand at home.
And its pumps both give the same amount ie, not the correct ratio, you've got to give two pumps of one and one pump of the other.
It looked funny as I mixed it but hey, a 2:1 ratio isn't that easy to see. Pity I slathered my two bits of ply and clamped them together before I pulled out my trusty electronic scale and did some tests.

Yep. I've carefully covered two pieces of plywood with a 1:1 mix of goop whereas they should have been covered with a 2:1 mix of epoxy.

And a quick read of the instructions would have seen me doing the right thing.

I hereby enter myself for the goose of the week award.
And the sad part is, it's not even a particularly creative stuff up.

Cheers
Richard
building 'Redback', if he can get the epoxy mix right

[ken mcclure]

The way I figger it, I'm going to bugger something up on every project. So in order to get it out of the way, I usually go ahead and do a bonehead thing right at the start so as to permit the rest of the job to go as planned.

For instance - in an assembly project I whack my thumb with a hammer right off. I know it's coming, so the pain is expected and there's not the usual spate of invective to be overheard by my 5-year-old and any of her crew who may be lingering around the shop.

In a glue-up I either mix a bad ratio or spill the glue depending on the mood.

And in a cutting phase, I go ahead and cut something too short. I know it's gonna happen, and this way I get to choose the stock that it happens to.

One time I forgot to do the sacrificial boner. The offcut from my workpiece slipped at the completion of the cut, contacted the saw blade and kicked back - striking me directly at the meeting point of my forked end. The good news is that the piece (when I was able to examine it the next day) was NOT cut too short.

So consider your goo-up to be the sacrificial boner and take yourself off the goose list. smile.gif

[NormMessinger]

Don't worry. Goose greese has it's applications.

I learned that one does not, give or take some, put five pumps of resin and five pumps of hardener, because for sure some distracation will make me loose count. One squirt of each and repeat as required. redface.gif

[Steve Lansdowne]

I did the same thing, and then 15 minutes or so after slathering the mixture on the bottom of my hull I realized my error. Not wanting to later have to scrape off all that goop, I added the missing component to the goop already on the bottom and mixed it in place, then realized I had too much volume overall and scraped off the excess. Miracles of miracles, the next day it had all set up OK!

[Tom Galyen]

Ken,

Just as long as the screw up doesn't happen while you are trying to perform the sacrificial screw up.

For instance while trying to do the sacrificial short cut you screw up and short cut a piece of anatomy that should not be short cut by anyone but a Rabbi.
:eek:
Tom G.

:D

[brian.cunningham]

Have you ever ran for the door shouting

"The epoxy's kicking!!

[John Blazy]

Ah, Daddles, just wait til you get good and confident in mixing up larger batches, but completely forget about the warmer weather you may happen to be in, and you create a pot of smoking paperweight stock.

Or worse, when you mix up a batch of filleting googe and make a mixing blade for your drill to really beat the cab-o-sil and fairing filler into the mix, but realize the hard way that the shear created by the spinning mixing bit creates its own heat starting a chain reaction.
Most of the time I can get it into the plastic icing bag . . .

[Aramas]

Is that all? Come on now, you're just not trying. After all, a boat is just a series of stupid mistakes that were fixable.

[daddles]

You will all no doubt be dissappointed to hear that the goop turned into solid goop overnight and that I have successfully mixed and applied my second batch.

Now, my question, serious this time, is how good is that first batch?
It's BoteCote - an aussie brand. Their website says that too much hardener will reduce the strength of the epoxy. Ordinarilly, I'd just bin lot and try again. However, the gluing surface was 60mm wide - I was laminating two bits of ply together - and the piece on top is only giving some thickness to the inwhale of the transom - this boat is unlikely to ever carry an outboard. My thinking is that with that sort of gluing area, with epoxy that has indeed gone off, on a joint that if it fails will NOT sink the boat (though there is impressive potential for really pissing me off), it's okay in this case to use the parts.
Oh, and learn from the experience.
Any thoughts?

Cheers
Richard

[ken mcclure]

I think I'd call the manufacturer and describe the situation to them. They should be able to tell you just what to expect.

And yeah - premature amputations are not to be attempted for the sacrificial boner (ahem) phase.

[John Blazy]

I wouldn't worry Daddles, about the joint integrity with the wrong epoxy mix. You may have overkicked it, but that simply adds to the brittleness a little. In this case where you have a ton of surface area gooped up, you also do not have much stress load, maybe a little shear stress - still stronger than most other glues. The only thing that would expose your glue joint's weakness would be if someone took a sledge hammer to the middle of your transom in the dead of winter.