Loose Foam Block Repair and Inspection Ports install

[minas man]

The symptom were hearing loose blocks when boat was being flipped, soft hull bottom and deck and hull very noisy with banging sounds when sailing in choppy conditions.
First cut 3 holes for 6 inch inspection ports but do not install ports until foam block repair is complete.


The 3 holes will be a the access points for the repair. You will need a good light source and I needed lot of spare bulbs.


You can see the loose foam blocks. I had to scrape away lots of failed adhesive from the deck side only and then vacuum out the hull. I did not scrap out any foam that was still intact as it helped set the loose blocks in place if I were to remove it I would have needed a gallon kit instead of a 2 liter kit of 4 LBS two part urethane foam.



The 1980 hull in position to fix the loose foam blocks using gravity and flipping boat to the other side when needed.
Get your foam ready and mark your tools so you do not cross contaminate. Consumables are gloves and your one time mix cups NO WAX cups and Tape to protect the gelcoat from the very sticky foam mix. Small batches about 1/2 cup in Total of the A + B. I mixed about 2o batches. The larger the batch the faster it will turn to foam. These 1/2 cup total A + B were having to be poured out in under 60 seconds at 70 degrees. Once the foam was all poured I used a hair dryer to heat the inside of the hull. I have more pictures but they are not uploading so I will post again to complete the fix.
Minas man

 

[minas man]

Here are the other pictures. Using tape and paper to protect the gel coat finish


Blocks now secure with new expanding 4 LBS two part expanding urethane foam. Important note, this is a structural foam for the integrity of the hull so it is important to use the correct density foam and not the more common 2lbs foam that is for floatation applications.

Curing the new foam with heat.



Inspection port in and ready to sail again.


The happy boat owner with a sound hull.


I will be doing this repair to my own boat later this month.
Minas man

 

[tag]

it's a messy job, isn't it!?! nice pictures of the step-by-step progress.

one thing I found was that if the gap between the foam block and the hull was large, and the mixed expanding foam was still on the runny side, it would run right down between the block and the hull, and not actually settle in place where I wanted it to! aside from keeping scraps of the old expanding foam around to help fill that void, I'm not sure of the best way to solve that problem, though.

cheers,
tag

 

[minas man]

Good point tag, I experienced the same problem which can waste the foam. Make a mold lined with wax paper about the size of the large gap and pour in a batch and then let it set up then cut to fit the large gaps and then pour in a new batch inside the hull to secure the whole mass.

Minas man

 

[tag]

minas man - that's a great idea. probably better long-term solution than me re-using the junk old stuff I was trying to fix in the 1st place!!