Monday, February 14, 2011

bulb to keel

İ am really gratefull to all the first builders who documented their builds with great blogs. Those guys are heros because they all did it with no previous many details to think about and those guys did it all for us.
So my special thanks on this post goes to Jeff - Alchemy and Kevin - Pipedream who greatly detailed how to drill lead. What I did was follow their advices...nothing else.

First I used my drill driver to slowly drill the pilot holes with a 6mm metal bit. Went slowly, used oil which made it really easy for the lead to get loose from the bit grooves, and set the clutch to about 14 out of 20. That set up saved me from broken too many bits....Actually the first first bit popped after maybe 1 mn. I was too much in a hurry to drill though that apparent soft material. So I took my time, changed the clutch setting and did not break any other drill bit.

After the pilot hole was drilled all the way through, I drilled the counter sink. For that I used a 22 mm wood spade bit. It worked fine and I removed nice shavings as you can see in the picture.
However I had to switch back to my regular portable drill because my drill driver simply did not have enough power. It does take some stamina to remove large shavings of lead !
After all 8 pilot holes were drilled all the way through the lead bulb halves, I cleaned up the recess space I had left when pouring the lead and adjusted the keel inside .

I took my time to take measurements and be absolutely sure all holes were ok and the keel was fitting nicely in the bulb recess. Long 6mm wood drill bit and holes were very quickly drilled through the hard wood. No turning back !
Than I switched to a larger 10mm bit and re-drilled all holes.

Bingo, I was done.

All I had to do was to remove the very heavy halves, and put them aside on their brand new little cart. It is SOooo easy to move them around my garage now ! No more back pain...
I will now buy the stainless steel bolts, assemble, fair and set aside the whole bulb to keel assembly.

Saturday, February 5, 2011

Rudder Part 1 : Shaping

Learning is part of this building experience. And it comes from doing things over and over. So when time came to shape my rudder, I knew I was not going to make the mistakes I made while building my keel .

First was the choice of wood. I found a nice red cedar in Turkey which looked nice, smelled great and is a treat to work with. What a difference a softwood does for shaping ! I must have been nuts to do my rudder in oak !!!!!

Second was the time spent to prep the plank. I did everything by the book , like cutting strips, flipping them, epoxing them back together but instead of cutting them at home with my circular saw, I asked the guys where I bought the wood to do it for me. 5mns later I had perfectly sized, identical rips of red cedar. Nice

Then the tools. This time I bought myself a hand planner. For whatever reason, I can't work with my eletrical one. It simply does not do the job. So I took my time to sharpen the blade on a oily stone, and smoothed out both sides of the plank. The planner was smoothly running on the wood, and it made a pleasant noise to let me know everything was good. Wood working rules !

When that was finished, I used a router to drill a 5mm deep channel on the leading and trailing edges of the blank. That channel was filled with resin and silica. It will be used as a reference of where both halves should meet and will give the extra strength needed on those extremities.
Having a center reference around the blank is quite important. İ know it because when shaping my keel I lost the pencil drawn line on the blank which made it really hard to finish off leading and trailing edge symetrically.

İ carefully cutted the rudder template which was printed on an A3 sheet, glued it to a piece of ply, and carefully cutted the wood following the dotted line as close as possible. Sanding block and paper were used to smooth the contours.

İ did this twice and then glued the ply templates on each side of the blank, making sure they were perfectly aligned with the center line on the blank. İ confirmed their exact location by taking a few measurements on each side. They matched, so İ knew the templates were well positionned.

So to make a long story short, I had a perfect plank before I really got serious with shaping my rudder. And all that prep was well worth it ! İf you are shaping for the first time, please take my advice for what it is worth and spend as much time as necessary to start off with a nice, smooth symetrical blank.

Then the fun started...

-İ drew longitudinal lines every 4 cms on the blank top and bottom sides

-Using my router with a guide, İ follow the lines and digged channels all across the length of the blank. To do them properly, İ would first align my router on top of the line, lock the guide in place, then lower the router bit until it would almost touch the ply template glued on the side.

On the first few channels İ routed, İ was not too agresive because İ wanted to avoid routing too deep. But during the process İ gained confidence and ended up routing channels with almost no space left with the template. They came out nice. As a matter of fact, so nice that İ routed those channels every 2cms ! That left me little wood to remove with the hand planner.

-once İ had all those channels routed, İ used my leftover blue spray paint and lightly sprayed the whole blank to give me a visual reference of the level İ had to plane down to.

-Hand planner in action, blade sharpened and set at about 2mm. İ very quiclky remove the wood left on the upper channels. The picture below was probably after 20 mns of work.

Another 20 mns and İ got to that point seen in the below picture. İ was gaining confidence in my plaaning abilities.....and therefore kept going.

İ reduce the depth of the blade to less than 1mm and maybe another 20mns later came very close to a pretty smooth surface without even using my sanding board. All the blue paint was almost gone and the wood just feeled pretty smooth to the hand.

I finished it off with my recently built longboard and my large rectangle orbital sander. Basically all I had to do was to carefully send the last mm or so until all paint was gone. I took my time to do it properly and all the paint pretty much disappeared all at once. I was finished.
That is what it looks like.

A closer look :

The resin+silica putty I put inside the grooved channel, makes for a nice and solid traling edge

Same for the leadind edge. It was easy to fold since the visual reference was very clear.

Overall I must say I am very happy with the result. I can definitly say I learned my lesson and do not fear any longer building a keel or a rudder. Great experience.