It's stuck! How to shift a recalcitrant centre plate bolt?

I can't understand what you find difficult to grasp. Turning has nothing to do with it. Read the second sentence again.
Drilling out is pointless. The keel has locked itself in the groove in the pivot bolt.

If I lived down there I'd come and do it myself.
 
That is why I suggested raising the plate bodily vertically in the most likely direction of the wear slot/s to hopefully disengage them and get back to alignment of the round bits, and then clobbering it.
 
For anyone who can't visualise it.......... Lift keel, bash out bolt.


Centreplate%20bolt.jpg
 
Nice phrasing for a Finesse 24.

The snag with drilling it out is it looks like a lot to drill, and it will probably shear at the plate, so will still need drifting out just harder to reach.
 
If the bolt cannot be drifted through and is not turning freely and there is a gap between box and plate (but insufficient for a hacksaw frame) then it may well be possible to use a 600mm mechanical hacksaw blade used manually (and of course with the plate suitably supported) to cut through the bolt on each side of the plate.The diagram suggests that this is possible from below.Such a blade has a degree of stiffness because of its width,e.g. 40mm,good reach and pressure can be applied because of the length,and it's very easy to make a comfortable handle by wrapping one end.It's just possible that a metal blade in a scorpion power saw or similar (a sabre saw - 300mm blade for metal,hire £25 + blades +p.p.e. ) would reach.A thin plate could be used to protect the woodwork inside the box.There is the danger that the bolt will rotate during cutting,but this is also likely to occur during drilling

(neither mad thank you,nor gratuitously rude)
 
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If it wont come out with a hammer I would devise some sort of extractor ,this would mean fixing a plate to the head either welding or bolting after drilling and tapping possibly 10mm if allowed, the plate is made with two or three threaded holes and bolts are tightened in sequence to keep the offending bolt under tension while you tap the other end or move the drop plate about. This is standard engineering stuff and you may be able to purchase an extractor plate close to what you might need but without a picture my suggestion may be way out,good luck.

http://www.greenpartstore.com/assets/images/merchandise/2013/jdg1560.jpg

Something like this but scaled up to suit larger bolts and heavy plate.
 
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bluerm166 said:
If the bolt cannot be drifted through and is not turning freely and there is a gap between box and plate then it may well be possible to use a 600mm mechanical hacksaw blade used manually (and of course with the plate suitably supported) to cut through the bolt on each side of the plate.The diagram suggests that this is possible from below.Such a blade has a degree of stiffness because of its width,e.g. 40mm,good reach and pressure can be applied because of the length,and it's very easy to make a comfortable handle by wrapping one end.It's just possible that a metal blade in a scorpion power saw or similar would reach.A thin plate could be used to protect the woodwork inside the box.
Click to expand...

A hacksaw blade ? Are you mad ?! Post #10.

Parbuckle,

not sure about welding in a wooden boat, then I did suggest heating the bolt with a blowtorch.

FinesseChris will have run for the hills by now...
 
Would it be possible to get a short length of good quality thin wall stainless tube which is a tight sliding fit over the threaded end of the bolt? Then someone to wiggle the keel plate while you drive the tube in over the bolt. In effect you're inserting a 'bearing' which will allow you to knock the deformed bolt out, followed by the tube when you've taken the weight of the keel plate with a jack or wedges....Sounds ok BUT depends if there's space round the bolt to fit the tube..:confused:
 
Without photos it may be stabbing in the dark but any suggestions other than more hammering could be helpful and should not be scorned, I did suggest the option of drilling and tapping but also not all welding has a flame.
 
Don't have clue about finness.

When all else fails. Ie spanner. socket, stillsen, hammer, chissel. I use a center punch and a drill to remove old blots or studs for larger diameter bolts.
cener punch, small diameter bit, then larger diameter bit.
you will want to take weight of so as to avoid drilling into material of keel.
 
Reading all the above,it sounds like Downsman has the basic idea but why not make the 'tube' a cutter like a box spanner with teeth,just slightly larger than the bolt diameter on one side of the casing at first, after taking the weight of the centreboard, then punch through the domed end of the bolt. After and if the bolt is successfully removed, enlarge the hole on the opposite side and fit a sleeve/bush of Tufnol and fit a new bronze or other bolt that passes completely through the casing. Enlarge the hole in the centreboard to suit the sleeve diameter. The wear to the bolt should be minimal if at all ,and no reaction of differing metals, lasting longer too.
I appreciate the initial removal is the problem but the suggested solution is an idea to prevent a recurrence.

ianat182
 
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parbuckle said:
Without photos it may be stabbing in the dark but any suggestions other than more hammering could be helpful and should not be scorned, I did suggest the option of drilling and tapping but also not all welding has a flame.
Click to expand...

ianat182 said:
Reading all the above,it sounds like Downsman has the basic idea but why not make the 'tube' a cutter like a box spanner with teeth,just slightly larger than the bolt diameter on one side of the casing at first, after taking the weight of the centreboard, then punch through the domed end of the bolt. After and if the bolt is successfully removed, enlarge the hole on the opposite side and fit a sleeve/bush of Tufnol and fit a new bronze or other bolt that passes completely through the casing. Enlarge the hole in the centreboard to suit the sleeve diameter. The wear to the bolt should be minimal if at all ,and no reaction of differing metals, lasting longer too.
I appreciate the initial removal is the problem but the suggested solution is an idea to prevent a recurrence.

ianat182
Click to expand...

Good grief. It is not "more hammering". Have none of you grasped the problem? Once the bolt and holes are once more concentric, drifting out the bolt will be a mere tapping.

Fitting a bearing in the plate sounds and excellent idea.
 
If this ever gets to the stage of re building, you could easily use a composite bush bonded to the plate with epoxy to prevent this sort of wear in the future.
 
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