I did some yachtrodding... Or at least pulled some hotrodding tricks out working on the boat.
Once at the boatyard, I glued up a stack of polystyrene sheet with 3m 77 spray adhesive. (Not recommended for longevity, but long enough to make a form...)
I took my stack and cut it out to fit the prop aperture. I used a Stanley Surform plane... (Same one I use for planing end grain of plywood, and working with luan....) and worked it down to a shape that was fair to the keel, and the same thickness as where the rudder rests.
I then took a 1/4 inch off, everywhere. Which wasn't quite enough... and covered the thing in biax scraps. The last time I did this I was making car parts, and had to cover the piece in Mylar as I was working with polyester resin.... and 1.5 ounce mat. The surform works, but an autobody file (big cheese grater) works wonders. I also built an electric hot wire to do it, but all that stuff is stashed at my folks house 250 miles away.
I cooked some polystyrene., but the outer shell is there. I'll probably end up filling it up with acetone to dissolve the foam then troweling in a putty of thickened epoxy with milled glass fiber and grinding it to fit where needed. The alternative is to cut it in half, and glass it as two clam shells, stronger, but more work for what is really just a glorified fairing.
I took a wooden dowel, 1 inch in diameter, and wrapped in aluminum foil (Used it as mold release in the past... Crinkled up, didn't let go of my half round. You see, the aft end of my keel has a fairing strip running each side of the rudder shaft that I want to replicate, as I' haven't decided when I rebuild the rudder if I'll use a 1 piece shaft and a massive gudgeon, or keep something similar to the stock setup. I tossed the aluminum/epoxy composite form (Hehe...) off to the side in the junk pile. I then took some waxed paper and wrapped said dowel...
I used wax paper as the release to keep my foam hunk from getting glued to my new table. Didn't work... epoxy got hot enough to melt to the wax paper... I sliced off the edge on the bandsaw to keep from grinding wax into the part.
(That wasn't chronological...)
While I had the fiberglass out, I laid another layer of 1708 biax over the starboard side. I did the starboard side while she was floating, and only got one layer down before haul out. I was stuck in first gear, not wanting to grind through the glass, but also wanting to rough it up... I spent 15 minutes with a random orbit going nowhere fast, before going out to the truck and getting my grinder with worn out brushes. It has a soft 6 inch pad... a thing of beauty, takes adhesive backed sand paper discs... I held down the switch, and spun the pad... and she worked. In the first minute I did more with that 40 grit disc than I did in the previous 15... I got almost done, until she would run no more. The rest I did by hand chasing down shiny spots along the corners and resin lumps. I did the whole 8 feet in one shot. Mixed up 16 ounces of resin, brushed on a hot coat, unrolled the fabric and got to wetting out. Once I got that on, I hopped off the staging, mixed up another batch... Stirred with one hand, and rolled what I wet out with the other. When everything was wet, and the excess pushed all the way aft into a puddle on the gel-coat... I put up a tarp and hung around chasing air bubbles and excess resin out. My tarp didn't cover the forward foot, so I have a few bubbles... I'll grind that back and do it again when I rework the chainplates.
Yeah, it'd be fine to have a dime sized air bubble... but that just bugs me till I fix it.
With that done, I took a piece of oak dowel and popped out the cutlass bearing. It was held in with marinetex... sweet. I took a piece of adhesive backed sandpaper and slipped it around the dowel to ream out the stern tube. After sufficient sanding, I ran an acetone soaked rag through till I was satisfied it was clean. I mixed up some tickened epoxy, and took a small piece of dowel and a little bit of glass. I wrapped up the external part of the stern tube (bummer, as I already sized my ear shaped aperature filler... have to modify it...) in glass. I slid in the dowel till it stopped, on the shoulder that indexes the cutlass bearing. I packed it full of epoxy, and put my little disc of fiberglass over the end of the hole. I don't want whatever I do as far as the engine-dectomy goes to be overly permenant in the event I want to put an inboard in the future. I'm not going for a "Never had one" rather a buttoned up "blank slate."
At this time, I noticed that my four ounce pot of thickened epoxy was smoking... and decided I might have mixed a little bit to much.
After that it was lunch time. (Around 3:00...)
I did some grinding on my through hull patches to get them started fair to the hull. I need to cut a new batten to follow the curve... but as with everything I do, I went way thick on the first few layers so there is plenty of meat to start with. If the weather holds I'm going to get rid of the rest and swap out my sink through hull for a seacock. (I want to move my cockpit drains above the waterline... lately i've been thinking of a redesigned cockpit....)
I got back, and started fitting my bulkhead. I took my length of steel angle iron and cut it into two 3 foot pieces, and ground down the ends so there would be no sharp parts. (don't want the boat getting hurt.)
I took 2 of my big clamps, and clamped them to the port bulkhead, and used spring clamps to hold the starboard floating free in the air... perfectly aligned with the starboard bulkhead. I took my 5/8ths blocks (don't cross cut stuff that skinny on a table saw.... Caboom... hit with a pile of toothpicks. (Grin)
I measured down the hull to my reinforcing stringer, and measured down my bulkhead template, took my compass and pulled a curve. I took my jigsaw and cut it out, then dropped it in place. I went around the stringer with my compass set to a 1 inch radius, marked it, and followed the contour under the deck, which had a 1/2 inch clearance at the cabin top, and 1 inch at the deck height.
I took this information, and cut another. I took my 1 inch radius marked out for the stringer, and made a few concentric rings from its center in half inch intervals... Cut the smallest, second one was the charm. Bulkhead dropped right in place with 5/8ths clearance the whole way up. The deck was a little tight, so I took a paint stirrer and held it to the edge, tracing a line 1/8th inch plus a pencil... 2 passes with the jig saw and it was perfect. (Imagine french chef making kissing noise)
My new beam set up rock solid... I pulled it out of the jig tonight. Another thing out of the way.
The inch and a half piece of flat bar I'm going to grind down to fit my through hulls, and turn with two crescent wrenches. Doesn't take long to grind, though don't lean on the grinder so hard that it anneals the steel... grin. If she turns purple, ya got to hot! I learned my art of grinding doing sheet metal repairs... Done my share of finding air on the other side of fenders and such... it takes light touch or everything in the world goes wavy, and thins out. Fiberglass is cooool, cause it has layers to tell ya when to stop.
That's about it for today. Tomorrow I'm satisfied to cut out my marine grade BS1088 3/4 plywood and turn them into a bulkhead. I'm crossing my fingers that the work done with the starboard pattern will transfer over fairly nicely to the port side, as it is on the chopping blocks too.
All for now,
Zach
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