Steel floor trapped behind the stringer

[JonnieFlamingo]

Hello,
I've had a productive weekend removing all but two of the steel floors from Flamingo (http://justflamingo.com) prior to sending them off to be galvanised. One of the remaining two is trapped under the massive baulk of timber, the mast step, and the other is trapped behind the stringer. The mast step one is a pain but just needs to be unbolted and freed up, the one trapped behind the stringer however is a different matter. I can reach all but the top bolt on each end which is well and truly covered by the 5x2 stringer. Short of dismantling half the boat I'm not sure how to approach getting it free. Has anyone else experienced this issue?
Jonnie.

 

[sampeeter]

When removing and replacing stringer material, observe the following guidelines:

Duplicate the shape and dimensions of the original stringer. Stringer height is critical to stringer stiffness.
In addition, where the stringer is supporting a cockpit sole, cabin sole or engine, the height of the repaired or replaced stringer must be the same as the original. If not, you will have a great deal of difficulty reinstalling the equipment.
Duplicate the original core material or find an equivalent material. Use wood where wood was used, plywood for plywood, foam for foam, etc. Attempt to duplicate the species of wood used in the stringer as well as the dimensions of the wood. You can use a more cavalier approach to replacing low-density core materials than you can for active cores.
Measure the thickness of the fiberglass skin and duplicate it. On stringers with an inactive core or molded stringers (with no core), watch for variations in the skin thickness. Occasionally, the top skin of the stringer is thicker than the side skins. This “cap” can significantly increase the strength and stiffness of the stringer. If the extra thickness is present, try to duplicate it.
Locate newstringers as close as possible to their original position. This is especially true of engine stringers or stringers that support other equipment. Increasing stringer spacing can also reduce panel stiffness.
Support the hull. If major stringer replacement is necessary, be sure to support the hull well so the original shape is maintained. Stringers that are removed or have broken away from the hull may allow parts of the hull to sag.

 

[johnlilley]

Difficult without seeing the dilemma, but one possible way is to drill a hole through the stringer to access the bolt head, drill off & punch through. Provided the hole is exactly in the correct position & not oversized the loss of strength on a large section stringer with a 1/2" drilling would possibly not be as much as the risk of leaving the floor untouched if the fastenings are failing. The stringer could be restrengthened by locating a long tapered butt plate over that section if felt necessary. Taper the ends to avoid a hard spot and screw on with bronze screws.

John Lilley

 

[JonnieFlamingo]

Thank you John, you are fast becoming my go-to-guy for this project!