Sunday, August 10, 2008

Trickery

Ok droid fans, lots of developments today.

After some trial and error, a couple of false starts, and some cursing, I made some headway fashioning the top of the boot for the center foot today. I cut the trapezoids out of PVC sheet (1/4"). All the angles are complicated. It was probably obvious to someone with more experience reading blueprints than me, but the height measurements given for the feet are for the height of the profile, not the actual height of the pieces. Since the sides of the feet are angled back towards the center, their actual height is taller. Some math with the Pythagorean theorem helped me get the measurements.

Once I had the ziggurat assembly cut and glued up, I came up with this trick to cut the slot through the foot where the connection to the leg will go. I flipped the piece over, set my tablesaw up, and made several passes through to remove the material:



This trick saved me a lot of trouble because calculating the angles and cutting these notches out of the pre-assembly pieces would have been a lot of work. With the saw, it took me 30 seconds to get it all perfect. I also cut it so that the pieces that go in to fill the notch would overlap out onto the face of the foot:



I cut these three pieces a bit long so that once they dried I could sand them down on the belt sander to be exactly flush with the rest of the assembly. If the joints had been on the inside, it would have been a lot of work to get them smooth.

Next, I tried something new with the legs. I want the painted finish on them to be as smooth as possible when I'm done. I don't want any wood grain showing through. So I am trying a coat of grain filler. It's a goopy, wet sort of filler that you wipe on. It fills all the really small crevasses in the grain. That's how they get those mirror finishes on fancy French dining tables. I am hoping that with a coat of this before the primer, I'll get good results. We'll see. I'm sure there are experts out there who could really fill me in on how to do this right:



Next challenge: On the curved and angled pieces towards the bottom of the legs, there is a little slot that is cut out of the angled face. Look here on the real McCoy just above the ankle cylinder:



Getting that little slot cut out has made serious headaches for lots of builders, I think. Here's what I came up with. I have the curved, beveled piece already fashioned out of stacked and sanded MDF. I set up my router table with a 1/4" bit, sticking up about a 1/16" (.060 in the plans, I think.). I flipped the piece over onto the beveled side and ran it all the way through, cutting a groove across the whole face:






Sorry that one's blurry.


But of course, it needs to be a little rectangular inset, not a slot cut across the whole face. So I trimmed down a scrap of MDF to fit snugly into the slot with some extra. I glued those into place carefully to fill in the slot where it is supposed to be flush:



The glue dried fast--it's hot as hell here in Sacramento now. And I carefully put the pieces to the belt sander to trim off any excess and get the pieces down flush. The results were just what I wanted and once their primed and painted, the added pieces won't show:



That's some sneaky ninja shit right there.

Next I have some devious ideas for building the little skirt that goes around the bottom of the feet with all the little rectangles cut out. Coming soon.

MM

2 comments:

Victor Franco said...

Very nice work, Matt! You are making great progress in a very short amount of time.

-Victor

Matt McCormick said...

Thanks Victor. I know that I have said it several times, but your extensive blog where you documented so much of the whole process has really given me a huge advantage. I feel kind of bad that I am not being as diligent about documenting my steps as you have been--that is, if anyone stands to learn from my work too.

MM