Last weekend I completed tapping the hole for the keel eye bolt. This is the last structural problem I had to solve before beginning the blasting, sealing and shaping process. Naturally, it went smoothly up until it didn’t.
Considering all that’s gone into fixing this keel, I was pretty nervous about screwing up the screw job. That’s why I had my friend JP come over. He’s really into cars and has tapped holes before. I know I do a lot of stuff on my own (with the help of YouTube), but I also like to have coaches too.
We got right to work. The first thing we did was level the keel.
Level keel prior to tapping
I used the keel tap I got from Catalina Direct and a tap driver I got from Home Depot.
Starting the tap
Cast iron seems very easy to work with. From what I read, it actually self lubricates as you work it. Pretty amazing.When we drilled the hole, we didn’t use any oil, and we didn’t when we tapped the threads either.
It didn’t even need to be backed out as we went deeper. We just kept turning and turning till it was in deep enough. Also, we only needed hand strength to turn it.
Deeper and deeper
Once the tap had gone all the way in, the filings were all at the bottom of the hole.
I used my pancake air compressor to blow them out. Yes, I closed my eyes. No, I don’t want to go back to the eye doctor.
Now, here is the not so great part. There is probably some trick here, but once it’s screwed all the way in, it’s perpendicular to the keel. No amount of changing where I start screwing it in makes a difference. All the way in = perpendicular. This may have something to do with where the tap is when you start. Not sure how we would be able to tell how it would wind up. It might also be that the area around the hole is not quite level.
If I back it off a bit, I can get it parallel with the keel, but then the shoulder of the bolt is not flush
Parallel, but not flush
So what do I do?
A) leave it perpendicular
B) leave it parallel, but with a slight gap around the shoulder
C) see if grinding down around the edge of the hole will let the bolt go a little further and wind up with the shoulder flush and the eye parallel. I’m a bit worried that I might screw up the threads and not make a different anyway.
OK you mechanically minded folks out there. What do you think I should do?
P.S. After we were done, JP gave me a ride in his race car – A lotus. He’s been building it the last 3 years to actually race on the race track. And wow, it does have some acceleration! Pretty too.