Aerocraft rebuild page 5

1980 Browning Aerocraft Mach II

Week 6, 15 Aug

Working in the shade makes a big difference on the bald spot.
A cheap blue tarp does the shading just perfect and keeps the wet out on the few rain days we've had.
I cut the cuddy door entrance wider and on center, It was only open on the port side. Cut the cuddy floor open. I was not going to remove it but, water kept seeping out so...More foam to be removed... Where's that Chainsaw?
Surgical Precision Insiscions: The best tool for removing mushy stringers and foam is an Electric Chainsaw.
Don't worry, it will not damage your hull, you will hear the difference in sound when it touches it. The electric ones are best ,since they are lighter and quieter when running. I wish I would have used it when I first started this floor project, it would have saved at least 2 days labor. Buy, rent or borrow one but, get one! It gets the job done in a hurry, Foam chunks will go flying everywhere ..
Next best tool is a sawsall with a 12" tree trim blade. Round the point on a grinder and have at it. Make cuts at vertical angles for easy removal.

Cuddy floor and foam gone.
It's a pain to get dressed up in the Tyvek suit., find goggles, mask and gloves. It took about 15 minutes to cut the floor and remove the foam. Another 10 minutes for the shop vac to do it's number.

Gas tank center support rotten and moldy.
You can see the difference in color from the saturated foam (dark) to the dry.

Saturated foam from under the gas tank. The black is wet mold !!
The division between the two halves is where the rubber strip is on top of the moldy wooden support. Although, as you can see, the foam displaced everything and the rubber strip never touched the tank.

The Gas Tank (standing on end) bottom just started to discolor from the moldy support. (arrow depicts the bottom side of tank).
I knew that if I left the tank in, I would have trouble or a corrosion leak and I'd have to tear the floor up again. By the same token, if I pulled it out I knew it would be fine. It is in great shape. But, "piece of mind" matters.

Two pices of foam cut about the same size, about 3" x 4"x 4".
If anything the DRY chunk is larger.

Weighed on cheap kitchen scale the Dry Chunk is a little more then 1 oz.

The Wet Chunk (from under the gas tank) weighed in at about 5 oz.
Not real scientific but, it does give you some idea how much more a boat weighs with wet foam. So, in about 48 cu. in. I had 4 extra oz. of weight.

I have to do a little more clean-up and roughing with 36 grit disks and I can start putting things back together. My quick math puts the space under my floor ( 72"x6" (avg.) x192") at 48 +/- cu.ft. for foam, tank & engine compartment (132" cu. in +/- ) less stringers and bulkheads. I ordered 2 gal. of 2 oz. pour-in closed cell urethane foam. Hope that's enough. The gas tank compartment will get no foam. I want free air space around it. The gunnels however, will be foamed in after I lay in the cabling duct PVC.

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Working in the shade makes a big difference on the bald spot. A cheap blue tarp does the shading just perfect and keeps the wet out on the few rain days we've had. I cut the cuddy door entrance wider and on center, It was only open on the port side. Cut the cuddy floor open. I was not going to remove it but, water kept seeping out so...More foam to be removed... Where's that Chainsaw?
Surgical Precision Insiscions: The best tool for removing mushy stringers and foam is an Electric Chainsaw. Don't worry, it will not damage your hull, you will hear the difference in sound when it touches it. The electric ones are best ,since they are lighter and quieter when running. I wish I would have used it when I first started this floor project, it would have saved at least 2 days labor. Buy, rent or borrow one but, get one! It gets the job done in a hurry, Foam chunks will go flying everywhere .. Next best tool is a sawsall with a 12" tree trim blade. Round the point on a grinder and have at it. Make cuts at vertical angles for easy removal.
Cuddy floor and foam gone. It's a pain to get dressed up in the Tyvek suit., find goggles, mask and gloves. It took about 15 minutes to cut the floor and remove the foam. Another 10 minutes for the shop vac to do it's number.
Gas tank center support rotten and moldy. You can see the difference in color from the saturated foam (dark) to the dry.
Saturated foam from under the gas tank. The black is wet mold !! The division between the two halves is where the rubber strip is on top of the moldy wooden support. Although, as you can see, the foam displaced everything and the rubber strip never touched the tank.
The Gas Tank (standing on end) bottom just started to discolor from the moldy support. (arrow depicts the bottom side of tank). I knew that if I left the tank in, I would have trouble or a corrosion leak and I'd have to tear the floor up again. By the same token, if I pulled it out I knew it would be fine. It is in great shape. But, "piece of mind" matters.
Two pices of foam cut about the same size, about 3" x 4"x 4". If anything the DRY chunk is larger.
Weighed on cheap kitchen scale the Dry Chunk is a little more then 1 oz.
The Wet Chunk (from under the gas tank) weighed in at about 5 oz. Not real scientific but, it does give you some idea how much more a boat weighs with wet foam. So, in about 48 cu. in. I had 4 extra oz. of weight.
I have to do a little more clean-up and roughing with 36 grit disks and I can start putting things back together. My quick math puts the space under my floor ( 72"x6" (avg.) x192") at 48 +/- cu.ft. for foam, tank & engine compartment (132" cu. in +/- ) less stringers and bulkheads. I ordered 2 gal. of 2 oz. pour-in closed cell urethane foam. Hope that's enough. The gas tank compartment will get no foam. I want free air space around it. The gunnels however, will be foamed in after I lay in the cabling duct PVC.