Remove & reinstall cutout on deck

[34Farrell]

I am in the early planning stages of what is likely to be a big project for someone who has never worked with fiberglass before and would like some advice.

I have to remove a 2' x 4' section of my fiberglass deck to haul out and replace a leaking 90 gallon aluminum diesel fuel tank. The deck is a cored composite about 1.5" thick. The route I am considering taking is to cut the section out with a circular saw (thin grinding wheel) set at a 45 degree inward angle around all four sides. I would then attach on the underside of the edges of the cutout a lip of some sort of material that I have yet to determine to use. Ideas would be helpful here.

Once the new tank is installed I would reinstall the 2' x 4' section and it would sit on the lip to ensure evenness with the rest of the deck. I assume I would still need to taper the edges of the cut both on the deck and the section to build up layered strips of fiberglass along. I assume too that I would need to apply some sort of sealer in the cut itself.

Am I on the right track here? Any ideas or considerations? I have all the tools and safety equipment for this job. Just a shortage of experience.

Thanks in advance!

 

[walt-oxie1]

Re: Remove & reinstall cutout on deck

The tapered cut idea works great, I have used it myself. When I put the piece back in place I put a few layers of CSM in the cut and weighed it down. I then ground about 6 inches on each side of the cut and glassed it back up and sanded everything flush. I made that repair about 4 years ago on one of my work boats. Like you, a leaking fuel tank is why I had to do mine.

 

[34Farrell]

Re: Remove & reinstall cutout on deck

Thanks for your comment. It's quite reassuring to know that I'm on the right track with this. I'll try the csm as an initial sealer in the cut.

 

[34Farrell]

Re: Remove & reinstall cutout on deck

BTW Walt, was it necessary to add a lip below the cut for the section to sit on or did the angle of the cut combined with the csm keep it level enough with the surrounding deck?

 

[walt-oxie1]

Re: Remove & reinstall cutout on deck

The CSM was enough to level it back out. It took 2 to 3 layers to make up for the removed material. I left about 2 inches sticking up above the floor. I dry fit it first. I didn't put anything under it because it is not in an area that gets any weight put on it although I don't think it will be needed.

 

[34Farrell]

Re: Remove & reinstall cutout on deck

Great advice. I'll give this a shot. Thanks again so much for your help!