Noah
05-08-2002, 07:05 PM
Ok, some of you will remember how I was replacing the keelbolts (and floors) in my 1958 Nordic Folkboat.
Anyway, I found a good way to do it.
My bolts only go about halfway down the ballast, where there is a pocket about 3" X 4". I drilled and chipped out the cement that was in the pocket and cut off the nut that was on the bolt using a sawzall with a metal cutting blade.
Once I had the nut off the bottom, I went up in to the hull, and cut a notch out of the floor around the bolt head. I went to the local scrap yard, and purchased a 4ft piece of anlge iron that was about 6" X 3", and 3/8's of an inch thick. (big and heavy) I cut a notch into the angle iron so that it would slip around the bolt, and catch on the head of the nut ontop of the floor.
I put one end of the anle iron on an existing floor, slipped the keel bolt into the notch, and then put a 3 ton hydralic jack under the other end. (working in a line along the keel ) Basically I created a lever that I could jack up and pull out the keel bolt with.
It worked pretty well. I had to get everything set up and in line, but I got the bolts out.
I was right at the edge of the jacks operating range, so I was putting a sh*tload of force on the bolts. I also found that it took a minute or two of constant force for the bolt to pull out, maybe more. I also gave each bolt a few hits while it was under tension to break things loose.
Obviously this will only work if you are replacing the floor along with the bolt, but otherwise it worked pretty well. Plus I didn't have to do any banging or swinging of hammers. (Except on the concrete)
BTW, my floors were in really crappy shape, but the bolts had a 1/2" left from 3/4". They would have lasted awhile longer without replacement.
Noah
Anyway, I found a good way to do it.
My bolts only go about halfway down the ballast, where there is a pocket about 3" X 4". I drilled and chipped out the cement that was in the pocket and cut off the nut that was on the bolt using a sawzall with a metal cutting blade.
Once I had the nut off the bottom, I went up in to the hull, and cut a notch out of the floor around the bolt head. I went to the local scrap yard, and purchased a 4ft piece of anlge iron that was about 6" X 3", and 3/8's of an inch thick. (big and heavy) I cut a notch into the angle iron so that it would slip around the bolt, and catch on the head of the nut ontop of the floor.
I put one end of the anle iron on an existing floor, slipped the keel bolt into the notch, and then put a 3 ton hydralic jack under the other end. (working in a line along the keel ) Basically I created a lever that I could jack up and pull out the keel bolt with.
It worked pretty well. I had to get everything set up and in line, but I got the bolts out.
I was right at the edge of the jacks operating range, so I was putting a sh*tload of force on the bolts. I also found that it took a minute or two of constant force for the bolt to pull out, maybe more. I also gave each bolt a few hits while it was under tension to break things loose.
Obviously this will only work if you are replacing the floor along with the bolt, but otherwise it worked pretty well. Plus I didn't have to do any banging or swinging of hammers. (Except on the concrete)
BTW, my floors were in really crappy shape, but the bolts had a 1/2" left from 3/4". They would have lasted awhile longer without replacement.
Noah