Keel / Building the FinAlison Gai20/6/2008 |
Notice the problem with the bulb stand I've made?....
The screws holding it together will be underneath when the bulb is rolled over.
So I won't be able to dismantle it when it weights nearly 2000 Kg!
It stopped the edges from chipping during the rollover, and then I turned it over.
The base is made from off cuts from the radius chime and the old form work.
I tried to roll the bulb over onto the pallet in the background but it went "through" the pallet.
I welded some cut links of chain the the top of the bulb which were handy lifting points and places to clip the welder onto.
The lifting scafold is 40 mm pipe from the offcut shelf of my local steel supplier.
The assemble here was enough for the bulb but it going to need more bracing for the whole keel.
I made the scafolding to be high enough to lift the whole keel but I didn't think of that when I put the bulb on those blocks.
My steel shop cut the pipes to size and angle from my template.
With a little balast of chain and a coat hanger, its sits in place waiting to be welded. The plumb and a ruler shows me its centered.
Then a bit of string and the 2nd pipe is done.
Before fitting the top plat to the keel, I fitted it to the boat.
The leading the trailing 2 bolt holes I drilled while the hull was upside down so I could align the sole.
The top plat template was made clamped to the sole.
The rest of the bolt holes were adjusted to align with the floors were marked but not drilled.
Drilling the holes was impossible to get straight.
I ended up drilling half way from outside, then cutting the tail off the template and using it as a guide to drill from the inside.
This was much easier.
The leading and trailing bolt holes are fit like a glove and I'll have to make them bigger to get epoxy in.
The others I filed out 3 to 5 mm oversize to get an easy fit.
I'm using 8.8 grade threaded rod with 8 grade nuts tacked to the top plat.
Watch where you put screws! This is a nice big 2" 12 G screw.
I ruined a good drill bit when I hit this screw.
I couldn't drill it out.
I ended up drilling round it then knocking it out with a screw driver.
Welding the top plat on, it all wanted to curl up, so a bit of bracing help keep it flat.
Before welding the top on I melted 100 Kg of lead into the pipes.
This came a little above the level it should have but 100 Kg is easier to remember when adding up the totals.
I Spent half the day cutting one side to fit, and then spent 20 minutes cutting the 2nd using the 1st as a template.
I did want to distort it by having holes in one side and not the other, so I didn't cut the holes for filling it with lead.
This I do when is one piece.
I welded the trailing edge then pulled the leading edges together until the forward pipe was contacted.
I drilled 10 mm holes in the skin and welded the skin to the aft pipe.
Then I pulled the skin to the leading edge and drilled and welded the forward pipe.
Initially I did 300 mm centers but later I halved it the 150 mm.
It must be 4 years since I scarfed the stringers and the offcut wedges still come in handy.
The threaded rod comes right through to the skin where it is welded to the skin.
I have done minimal welding to the nuts and bolts so as to not upset their hardening.
It was a tearful good bye to the keel as it leaves home for the first time! (to get sand blasted).