This page documents mistakes I have made while building my KR2-S.
All pictures on this page are at 240X320 and average between 3k and 10k in size.
If you click on the pictures, they will take you to larger versions at 640X480 that average between 90k and 170k.
I hope that there are not too many entries to make in this section,
but you never know when the stupidity bug will hit.
My first mistake was to get a little too aggressive while trying to "bend" the boat into shape.
While using my gusset clamps (bolts through blocks of wood) to bend the longerons I heard a loud crack.
Here is what it looked like when I pulled the side off of the table.
To fix my error, I marked out a scarf joint (this one is 10 to 1):
Cut it out:
Cut a new piece.
Epoxied everything back in place:
And here you have the finished product:
You may have noticed in the second picture that the scarf joint falls right over a vertical:
This led to my second oops! Once I got everything back together and on the table to start the bending process again,
The small amount of original wood left over the vertical became a weak point and failed when I started bending again.
This second time (sorry, no pictures), I changed the scarf joint to be 12 to 1 and made sure that neither scarf was
located over a vertical. To help strengthen the scarf joint, I have elected to extend the aux longerons by one bay
to completely cover the scarf joints. I may even add a single layer of 1" glass tape to help tie it all toghether.
19 November 2002
The next mistake comes from not having a good visual on what the plans are telling you to do. The plans tell you to leave the longerons for both sides a few inches longer than needed and that you will trim to length when you install the vertical tail post. I did exactly that, then when it came time to put the two sides together, I went ahead and cut them to length. The only problem with this is that since I cut them while both sides were flat on the table...
The lesson here is that make sure the final angles before you make that cut. This oops was minor compared to the previous one. Now my plane is shorter by approximately half an inch (not counting whatever length I lost by increasing the cabin width).
1 April 2003
Figure the irony. On April fools day of all days. Here is a picture of my aileron bellcrank template. Can you see I did wrong? Yep, these two parts are identical when they are supposed to be mirror images of each other.
I hope this ends the Oops! section and that there are no more to come....
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