Excellent idea with the foam pour creating the mold etc, I did something similar but pour marine foam across the entire bottom because I install a polyurethane tank.
Its an idea i will remember, good job and very informative post.

No I didn't use any cloth, after cutting the supports to fit I just used epoxy to seal the foam cuts to stop any absorbtion. I also coated the entire tank compartment with epoxy while I was in there. The form supports were also stops for the additional foam pour to stop the foam from running into the center channels, creating the corner supports. The foam when poured along the sides will run under the tank filling the corners under the tank and rising up the sides to provide more support from underneath, along with closing the corners on the side locking the tank in place. This was not my idea, I had copied some of the other members ideas that had done this type of replacement before..

:nice: Tommy

When I first became aware of the problem, it seemed like a major catastrophe, after calming a while and doing a lot of reading, (it was January!) I decided that either I could just go take out a loan to have it done, or attempt to do the job myself. On these forum's are a lot of other people that have tackled these types of projects, and were very helpful with advice, and how to's even to the extent of posting pictures. Afterwards, looking back, I'm glad I did the job myself, not only did I save what was probably a significant amount of money, I now have a confidence in my boat that is very hard to describe, along with the pride of doing what I believe to be a better job than what I may have obtained having it done by someone else.....

Tommy

Ah confidence...... :nice:

rabbitfish saw your posts, thanks for the pics. i will be facing a tank removal on my 1984 20' center console fisherman. i've removed the centerconsole and raised up the floor. can you tell me how tough/difficult it was to remove the tank. did thet liitle saw remove /cut the foam for you to pop out the fuel tank?

I thought i should post this, http://www.yachtsurvey.com/fueltank.htm , it seems foaming fuel tanks in isn't a bright idea anymore. The following is from the site i just linked:

Fuel tanks don't corrode because they get wet; they corrode because at some point something is in contact with the tank that traps water between it and the tank. Like the original foam that it was installed with. Aluminum is self-protecting, so long as the surface gets adequate air exposure. Severe corrosion is always caused by water plus a lack of oxygen.

makes me wonder, does the coal tar epoxy help or hurt the new tank? :head: