Keel Repair, Wet Foam - Moderated Discussion Areas

  ContinuousWave
  Whaler
  Moderated Discussion Areas
  ContinuousWave: Whaler Repairs/Mods
  Keel Repair, Wet Foam

search | FAQ | profile | register | author help

Author Topic:   Keel Repair, Wet Foam

sjp2 posted 07-25-2013 05:23 PM ET (US)
In getting home a newly purchased 1991 13 GLS for our first time to she how she goes on the water, I noticed a six-inch section of the keel had been damaged--holed--by the [trailer] roller [and a] bad repair job [had been made]. [I] took the console off and rolled over [the 1991 Boston Whaler 13 GLS] ,trimmed up the mess and dug out some of the foam, as per the instructions here. At the end of the cut along the keel I gouged out more damp foam. I decided to extend the cut--first mistake. I asked a person [familiar with] fiberglass to put a moisture meter on [the some part of the hull]. His opinion was that [the hull] was wet further up, [and he recommended] to extend the cut to allow [the wet foam] to dry--second mistake.
I extended the cut, now about four-feet long, along the keel [for a width of] about 1/2-inch.
I have finally awoken to the fact that I have cut out a lot of good fiberglass in an effort to get rid of damp foam. I could squeeze the water out of the damaged section, but the other part was a bit damp along the fiberglass. The form was reasonably dry.
How dry does [the interior foam of a Boston Whaler Unibond hull] really have to be to for the glass mash to set?
If digging out dry foam, is it possible that the [moisture] meter was reading the moisture content between the hull and foam?
jimh posted 07-26-2013 12:53 AM ET (US)
Whether or not a resin adhesive will cure and form a good bond to a material that is saturated with water probably depends on the adhesive resin being used. What adhesive resin are you using?
My uninformed and unscientific opinion is that most resin adhesives will not form a good adhesive bond to foam that is saturated with water. I recommend you test your resin with a sample of the wet foam from the hull. This will give you a much better indication of how your resin will bond to wet foam than anyone might be able to conjure.
I don't know the electrical principle on which a moisture meter operates. It is hard to assess what property the moisture meter was measuring or indicating from your narrative, as the exact location of the meter's probes is not well described. In any case, if you can perceive moisture in the foam yourself, you do not need a meter to tell you the foam is wet.
I recommend you allow the hull to dry and to encourage the moisture in the damaged area and in the area you have opened up to evaporate. Having the hull inverted may tend to move water away from the keel due to gravity. You might consider returning the hull to its normal orientation, and then letting any water entrapped flow downward with gravity and drip out through the opening you have made.
Concerns about entrapped water are common and are a frequently asked question. See the FAQ for more answers:
http://continuouswave.com/whaler/reference/FAQ/#Q3
sjp2 posted 07-26-2013 05:43 AM ET (US)
thanks for the reply jimh,i was making the mash out of unwaxed polyester resin,as mentioned the foam is not saturated further along and only at the top of the damaged section (thats why i was annoyed with myself for cutting out undamaged good keel section).as explained to me the heat of the resin causes the wet foam to generate steam (moisture)and therefore stopping the resin from hardening,but if the top of the foam has been dried out to say about 1to 1&1/2 inches possibily this would be enough to let the resin harden then i can overlay it with a few layers of glass mat ,which i intended to do for a keel guard anyway.as you suggested i will try a small area on the keel to see the effect on the resin mash,i did not intend my purchase to be a project ,but more of a pastime if you know what i mean.by the way the meter was placed about an inch either side of the keel.
dg22 posted 07-26-2013 02:26 PM ET (US)
Jim's idea of flipping the boat back over to let it drain and dry out is a good one.
I had a hole (1/2 inch by 3 inch) about 6 inches from the keel but was lucky as it is not exposed to the high pressure water when the boat is planning. It was still damp so I let it sit over the winter to dry and then used a heat gun to dry things up the best I could. I sanded the area around the hole down to the fiberglass to remove the gel coat and used a few layers of fiberglass mat and resign to repair. It was successful but it sounds like your repair will be more difficult as you will need to re-foam that area you gouged out. Best of luck.
sjp2 posted 08-07-2013 12:57 AM ET (US)
well i think i was panicking a bit with the heading (wet foam)i have since cut along a 7 ft section of keel ,and the foam seems dry to touch also repaired a 2" section near it and the foam seemed also dry ,i have just cut out a 10" x 2" section just above the wood (which is in good condition) in the diagram noted as B,here i discovered a hairline crack that had moisture coming from it when i used a air compressor to blow away some fibredust ,i feel the moisture was trapped in the glass because i cut away an old repair that a layer of heavy mat and a 1/4 " of resin underneath it with no fibre in it ,(but it did have a couple of rubber bands in it),it was brittle and cracked easily ,i could pull the mat away from it in parts ,all the foam surrounding this is dry also,which brings me to a question -instead of buying some expanding foam ,i instead got the green hi density foam the fibreglass people use for mouldings and esky's etc ,cut it to the shape of the hull and will glass it in ?tomorrow mr fibreglass is going to come around with his moisture meter,so hopefully i can finally glass up the keel and put a keel strip on it with a combination of flowcoat and zircon powder.

Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.

Author	Topic: Keel Repair, Wet Foam
sjp2	posted 07-25-2013 05:23 PM ET (US) In getting home a newly purchased 1991 13 GLS for our first time to she how she goes on the water, I noticed a six-inch section of the keel had been damaged--holed--by the [trailer] roller [and a] bad repair job [had been made]. [I] took the console off and rolled over [the 1991 Boston Whaler 13 GLS] ,trimmed up the mess and dug out some of the foam, as per the instructions here. At the end of the cut along the keel I gouged out more damp foam. I decided to extend the cut--first mistake. I asked a person [familiar with] fiberglass to put a moisture meter on [the some part of the hull]. His opinion was that [the hull] was wet further up, [and he recommended] to extend the cut to allow [the wet foam] to dry--second mistake. I extended the cut, now about four-feet long, along the keel [for a width of] about 1/2-inch. I have finally awoken to the fact that I have cut out a lot of good fiberglass in an effort to get rid of damp foam. I could squeeze the water out of the damaged section, but the other part was a bit damp along the fiberglass. The form was reasonably dry. How dry does [the interior foam of a Boston Whaler Unibond hull] really have to be to for the glass mash to set? If digging out dry foam, is it possible that the [moisture] meter was reading the moisture content between the hull and foam?
jimh	posted 07-26-2013 12:53 AM ET (US) Whether or not a resin adhesive will cure and form a good bond to a material that is saturated with water probably depends on the adhesive resin being used. What adhesive resin are you using? My uninformed and unscientific opinion is that most resin adhesives will not form a good adhesive bond to foam that is saturated with water. I recommend you test your resin with a sample of the wet foam from the hull. This will give you a much better indication of how your resin will bond to wet foam than anyone might be able to conjure. I don't know the electrical principle on which a moisture meter operates. It is hard to assess what property the moisture meter was measuring or indicating from your narrative, as the exact location of the meter's probes is not well described. In any case, if you can perceive moisture in the foam yourself, you do not need a meter to tell you the foam is wet. I recommend you allow the hull to dry and to encourage the moisture in the damaged area and in the area you have opened up to evaporate. Having the hull inverted may tend to move water away from the keel due to gravity. You might consider returning the hull to its normal orientation, and then letting any water entrapped flow downward with gravity and drip out through the opening you have made. Concerns about entrapped water are common and are a frequently asked question. See the FAQ for more answers: http://continuouswave.com/whaler/reference/FAQ/#Q3
sjp2	posted 07-26-2013 05:43 AM ET (US) thanks for the reply jimh,i was making the mash out of unwaxed polyester resin,as mentioned the foam is not saturated further along and only at the top of the damaged section (thats why i was annoyed with myself for cutting out undamaged good keel section).as explained to me the heat of the resin causes the wet foam to generate steam (moisture)and therefore stopping the resin from hardening,but if the top of the foam has been dried out to say about 1to 1&1/2 inches possibily this would be enough to let the resin harden then i can overlay it with a few layers of glass mat ,which i intended to do for a keel guard anyway.as you suggested i will try a small area on the keel to see the effect on the resin mash,i did not intend my purchase to be a project ,but more of a pastime if you know what i mean.by the way the meter was placed about an inch either side of the keel.
dg22	posted 07-26-2013 02:26 PM ET (US) Jim's idea of flipping the boat back over to let it drain and dry out is a good one. I had a hole (1/2 inch by 3 inch) about 6 inches from the keel but was lucky as it is not exposed to the high pressure water when the boat is planning. It was still damp so I let it sit over the winter to dry and then used a heat gun to dry things up the best I could. I sanded the area around the hole down to the fiberglass to remove the gel coat and used a few layers of fiberglass mat and resign to repair. It was successful but it sounds like your repair will be more difficult as you will need to re-foam that area you gouged out. Best of luck.
sjp2	posted 08-07-2013 12:57 AM ET (US) well i think i was panicking a bit with the heading (wet foam)i have since cut along a 7 ft section of keel ,and the foam seems dry to touch also repaired a 2" section near it and the foam seemed also dry ,i have just cut out a 10" x 2" section just above the wood (which is in good condition) in the diagram noted as B,here i discovered a hairline crack that had moisture coming from it when i used a air compressor to blow away some fibredust ,i feel the moisture was trapped in the glass because i cut away an old repair that a layer of heavy mat and a 1/4 " of resin underneath it with no fibre in it ,(but it did have a couple of rubber bands in it),it was brittle and cracked easily ,i could pull the mat away from it in parts ,all the foam surrounding this is dry also,which brings me to a question -instead of buying some expanding foam ,i instead got the green hi density foam the fibreglass people use for mouldings and esky's etc ,cut it to the shape of the hull and will glass it in ?tomorrow mr fibreglass is going to come around with his moisture meter,so hopefully i can finally glass up the keel and put a keel strip on it with a combination of flowcoat and zircon powder.