Thursday, March 3, 2011

Help Me, Obi Wan Kenobi

There is a scene in Star Wars - Episode III, where Obi Wan Kenobi and Anakin Skywalker are running down a corridor on a bad-guy ship, when the suddenly get captured.  Obi Wan turns to Anakin and says, "Wait a minute. How did this happen? We're smarter than this."  That's how I've felt this week.

Back when I dry fit the keelson, I had to do a little bit of jiggering to get things lined up at the trailing edge of the keel.  At the time, I wasn't too worried about it, but the more I've thought about it, the more I've come to accept that the keel is not perfectly symmetric.  Other Pocketship builders have reported having similar difficulties, and I tried to learn from their mistakes.  But my precautions weren't enough.  It is apparently just really difficult to glue of the keel of this boat and get it to come out straight.  So, I'm going to have some fixing to do.

This probably wouldn't bother me too much, if keelson totally covered the trailing edge of the keel, but alas, it does not.  My plan right now is to cut right down the centerline of the keel blocking up to the vertical blocking at the aft end of the lead compartment.  I'll then try to force the aft end of the keel to where I think it should be, and then slather everything with thickened epoxy (the cure-all!) and stick it all back together.  Of course, I had to figure this all out after pouring 85lbs of lead into the keel.

That reminds me, I did get a chance to pour a little more lead into the keel.  I reckon I'm up to 85lbs total.  This may be the most drawn out lead pour in Pocketship history (not that it has a long history).

Here's the problem...the keelson and the keel just don't line up.

On a different "fixing my mistakes" topic, the filling of my ugly scarf joints is almost complete.  Filling the ugly bits and sanding them seems to work well and make the surface nice and smooth.  I'm planning on painting all of these surfaces, so fortunately the key is smoothness, not beauty.  So, success!  Yet, as I was sanding thickened epoxy this week, I couldn't help but continue to kick myself for these ugly joints.   How did this happen?  I'm smarter than this. 

The (re)filled joints 

The sanded, filled joints.  Turned out ok.

Next up then, was to get some fiberglassing done.  The inside faces of both the lower side panels and the topsides panels get a layer of 'glass before assembling the hull (the outside faces get it much later in the build).  It is still a little too cold out in the shop to this kind of fiberglass work...I don't have enough worklights to heat the whole surface, and I'd rather do this with slow hardener than the fast stuff.  So, I spread out a couple of large sheets of cardboard  inside the house and set up to fiberglass the topsides panels there.  In retrospect, I probably wouldn't (won't) do this again.  Too much hassle, too much worry about ruining something inside the house.   Temperatures should be warming up soon, and I'll just have to cope until then.

At any rate, I spread the 'glass, the epoxy, and a layer of peelply out on the topsides panels.  Done right, the  peelply gives a nice, smooth surface in the end...no sanding.  In reality, it is very difficult to lay the stuff down on top of wet epoxy without getting wrinkles in it.  Those wrinkles lead to little ridges of epoxy...not nice. If you work hard, you can work out a lot of the wrinkles, but I have yet to perfect a method to get them all out, or even get most of them out easily.  Still, the vast majority of the surface ends up smooth, and hours of sanding are erased from the agenda, so it is worth it.

Spreading the 'glass

The glass cloth is trimmed back and we're ready for epoxy.

It is a little hard to see, but here both  panels are wet out and the peelply has been laid out.


At least I can still fiberglass compently.  So, next up will be some keel straightening and  bit of fiberglass on the lower side panels.

No comments:

Post a Comment