Re-Core Cockpit Sole
Moderator: Jim Walsh
Re-Core Cockpit Sole
This winter I plan to re-core the cockpit sole on Christine C. This summer we noticed an increasing softness in the sole and when I was under the cockpit a few weeks back I noticed a sag of about half an inch on the steel bracket mounting the pedestal and steering gear. Here's my plan. I would really appreciate any feedback you all have on how to do this.
First, I need to remove the Edson steering pedestal. I will rebuild the pedestal including the steering cables and repaint as part of all of this. I'll remove the emergency tiller deck plate. I will try to leave the cockpit scuppers in place.
Next, use a Festool or similar to cut out the cockpit top layer of fiberglass. Then use the same tool to cut out all the 1/2 in plywood (if I rememeber the thickness correctly). Then bevel the edges to 12:1. To do this I need to ensure the first cut is done about 1 1/2 inches in from the edge to allow for the ~ 1/8 inch fiberglass thickness.
Once all the old wood is gone, I will use some 2x4s or similar clamped to the vertical sides of the cockpit "box" to restore a flat plane to the fiberglass under the sole. Then I will fit in a new core material plane. I plan to use Coosa Bluewater 20 as the new core material. This seems like the rot free material that is closest in strength/weight to the original plywood. I would prefer to improve upon plywood for water absorbtion and the Coosa is only about $20-40 more than using plywood which is pretty insignificant for a project of this size. Epoxy the core in, weighing down with bags of sand. I'll drill holes from below to allow re-centering the old top fiberglass; if I don't reuse that, I will wait until the upper layer is replaced. Then either use the existing top layer cut out earlier if it is decent shape or just lay down new cloth. Also use sandbags here to ensure a good bond. If I use new glass I will cut out the e tiller plate hole. With the Coosa material I don't need to care too much about sealing the exposed edges.
Finally, I will refinish the gelocoat and refinish the antiskid, probably with KiwiGrip. Then reinstall the refinished pedestal and install the new steering cables.
I also plan to relocate the water heater to under the cockpit sole as part of the project. It seems like a good idea to replace all the steering cables and hardware at this time. I'll also replace all the seacock backing plates while everything is cleaned out but that's for another post.
Am I missing anything? Would you do anything differently?
Thanks!
Jeff
First, I need to remove the Edson steering pedestal. I will rebuild the pedestal including the steering cables and repaint as part of all of this. I'll remove the emergency tiller deck plate. I will try to leave the cockpit scuppers in place.
Next, use a Festool or similar to cut out the cockpit top layer of fiberglass. Then use the same tool to cut out all the 1/2 in plywood (if I rememeber the thickness correctly). Then bevel the edges to 12:1. To do this I need to ensure the first cut is done about 1 1/2 inches in from the edge to allow for the ~ 1/8 inch fiberglass thickness.
Once all the old wood is gone, I will use some 2x4s or similar clamped to the vertical sides of the cockpit "box" to restore a flat plane to the fiberglass under the sole. Then I will fit in a new core material plane. I plan to use Coosa Bluewater 20 as the new core material. This seems like the rot free material that is closest in strength/weight to the original plywood. I would prefer to improve upon plywood for water absorbtion and the Coosa is only about $20-40 more than using plywood which is pretty insignificant for a project of this size. Epoxy the core in, weighing down with bags of sand. I'll drill holes from below to allow re-centering the old top fiberglass; if I don't reuse that, I will wait until the upper layer is replaced. Then either use the existing top layer cut out earlier if it is decent shape or just lay down new cloth. Also use sandbags here to ensure a good bond. If I use new glass I will cut out the e tiller plate hole. With the Coosa material I don't need to care too much about sealing the exposed edges.
Finally, I will refinish the gelocoat and refinish the antiskid, probably with KiwiGrip. Then reinstall the refinished pedestal and install the new steering cables.
I also plan to relocate the water heater to under the cockpit sole as part of the project. It seems like a good idea to replace all the steering cables and hardware at this time. I'll also replace all the seacock backing plates while everything is cleaned out but that's for another post.
Am I missing anything? Would you do anything differently?
Thanks!
Jeff
Re: Re-Core Cockpit Sole
PS I promise to post pictures of this project! Usually I get everything too messy or too rushed (just prior to launch) to do that. My plan posting here is to force myself to slow down.
Re: Re-Core Cockpit Sole
Jeff,
your plan sounds good. I replaced mine a few years ago.
Yes, retain the scuppers and leave 1-1/2 - 2" of the perimeter all around the sole.
I screwed 1/2" marine ply to the bottom of the sole then glassed it with mat and bi-axial cloth, (working under the cockpit, kinda messy ! ).
Cut the perimeter above and removed the skin and rotted ply core. Used 1/2" marine ply core bedded in epoxy. The perimeter cut should leave a "C" shaped channel. Bevel the edges of the ply to fit into the channel, ( we used 2 pieces }. Then more epoxy, cloth, thickened epoxy to level.
Sanded, primed for 2-part polyurethane paint with non-skid. Very good results, solid as a rock !
I was told by a boatyard guy it would be a 3K job to have a pro do it.
Good luck
your plan sounds good. I replaced mine a few years ago.
Yes, retain the scuppers and leave 1-1/2 - 2" of the perimeter all around the sole.
I screwed 1/2" marine ply to the bottom of the sole then glassed it with mat and bi-axial cloth, (working under the cockpit, kinda messy ! ).
Cut the perimeter above and removed the skin and rotted ply core. Used 1/2" marine ply core bedded in epoxy. The perimeter cut should leave a "C" shaped channel. Bevel the edges of the ply to fit into the channel, ( we used 2 pieces }. Then more epoxy, cloth, thickened epoxy to level.
Sanded, primed for 2-part polyurethane paint with non-skid. Very good results, solid as a rock !
I was told by a boatyard guy it would be a 3K job to have a pro do it.
Good luck
CD 30c #42
S/V "Bluesails"
+ 41.69989
-70.027199
S/V "Bluesails"
+ 41.69989
-70.027199
Re: Re-Core Cockpit Sole
So I got back around to this project this weekend. After getting the cover on, I started with getting the steering pedestal off.
First step is getting off the pedestal guard. That was pretty easy. A couple screws at the blocks on the cockpit sole (which I had off about 4 years back) and getting off the compass, its lighting, the throttle and clutch cables, then the screws under. I took the cotter pins off the throttle and shift cables and removed the mystery screw on the aft side of the pedestal that apparently clamps them in place. The pedestal guard screws were a bit of a pain since they are supposed to be captive in the block but just spun; I had to grab them in one hand with channel locks while I got the nuts underneath with a ratchet.
Next, there are four large machine screws that hold the pedestal to the steel weldment under the sole. Here is what it looks like:
Several other CD30 owners have had trouble with corrosion here but this looks pretty good; surface rust so I will be able to just paint it.
The nuts came off the screws really easily. On the other hand the #$@^$ screws needed to be unscrewed by hand. They had some sort of caulk holding them in and taking the screwdriver back half of each turn I could manage. Then a putt knife between the pedestal and the sole, all the way around, and the pedestal came off. Uh oh. There was some water in the base. It looks like I have some corrosion too, just on the plate that guides the cables. Need to do some research about this.
Oh, while I was poking around, I noticed that the rudder tube stuffing box hose was pretty far gone. Better to find this now than halfway to somewhere on the ocean. I hope I can do this from the top without removing the rudder; I'm sure someone here did this before.
Next steps will be to remove the emergency tiller plate, fix the stuffing box hose and make a decision on how to handle the corrosion in the pedestal support weldment.
Jeff
First step is getting off the pedestal guard. That was pretty easy. A couple screws at the blocks on the cockpit sole (which I had off about 4 years back) and getting off the compass, its lighting, the throttle and clutch cables, then the screws under. I took the cotter pins off the throttle and shift cables and removed the mystery screw on the aft side of the pedestal that apparently clamps them in place. The pedestal guard screws were a bit of a pain since they are supposed to be captive in the block but just spun; I had to grab them in one hand with channel locks while I got the nuts underneath with a ratchet.
Next, there are four large machine screws that hold the pedestal to the steel weldment under the sole. Here is what it looks like:
Several other CD30 owners have had trouble with corrosion here but this looks pretty good; surface rust so I will be able to just paint it.
The nuts came off the screws really easily. On the other hand the #$@^$ screws needed to be unscrewed by hand. They had some sort of caulk holding them in and taking the screwdriver back half of each turn I could manage. Then a putt knife between the pedestal and the sole, all the way around, and the pedestal came off. Uh oh. There was some water in the base. It looks like I have some corrosion too, just on the plate that guides the cables. Need to do some research about this.
Oh, while I was poking around, I noticed that the rudder tube stuffing box hose was pretty far gone. Better to find this now than halfway to somewhere on the ocean. I hope I can do this from the top without removing the rudder; I'm sure someone here did this before.
Next steps will be to remove the emergency tiller plate, fix the stuffing box hose and make a decision on how to handle the corrosion in the pedestal support weldment.
Jeff
Re: Re-Core Cockpit Sole
Good luck, Jeff. Big job. Excellent pictures, and it very nice of you to share the experience and memorialize the project for all of us.
ORION's PO had the same job done by the boatyard where he stored her over the winter. I wish I had some detailed information of the project and the materials used. They placed a collar on the base of the pedestal to reinforce it where corrosion had compromised its integrity. It is a Yacht Specialties pedestal and the base is once again suffering from corrosion. Had I been the one effecting the repair I'd have replaced the pedestal, not repaired it. I am going to repair it again (it is solid and shows no movement) this spring, but if anything looks or feels less than trustworthy I'll be replacing it with an Edson unit. I'm looking forward to your future updates, and you are correct that now is the time to address the stuffing box hose and anything else which is easily serviced while the floor is removed.
Once again, thanks for sharing.
ORION's PO had the same job done by the boatyard where he stored her over the winter. I wish I had some detailed information of the project and the materials used. They placed a collar on the base of the pedestal to reinforce it where corrosion had compromised its integrity. It is a Yacht Specialties pedestal and the base is once again suffering from corrosion. Had I been the one effecting the repair I'd have replaced the pedestal, not repaired it. I am going to repair it again (it is solid and shows no movement) this spring, but if anything looks or feels less than trustworthy I'll be replacing it with an Edson unit. I'm looking forward to your future updates, and you are correct that now is the time to address the stuffing box hose and anything else which is easily serviced while the floor is removed.
Once again, thanks for sharing.
Jim Walsh
Ex Vice Commodore
Ex Captain-Northeast Fleet
CD31 ORION
The currency of life is not money, it's time
Ex Vice Commodore
Ex Captain-Northeast Fleet
CD31 ORION
The currency of life is not money, it's time
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Re: Re-Core Cockpit Sole
Very educational. And a great Winter job to tackle I'd think.
Skeep
Supporting Member #1576 of the CDSOA
Current Vessel, Alberg 30 Hull #614 to be named yet
Formerly S/V Hull #729 "Baggy Wrinkles"
Blogsite for Alberg Ty and Alberg 30 continues athttp://baggywrinkles.blogspot.com
Located at Lake Murray Sailing Club, Chapin South Carolina
Supporting Member #1576 of the CDSOA
Current Vessel, Alberg 30 Hull #614 to be named yet
Formerly S/V Hull #729 "Baggy Wrinkles"
Blogsite for Alberg Ty and Alberg 30 continues athttp://baggywrinkles.blogspot.com
Located at Lake Murray Sailing Club, Chapin South Carolina
- Sea Hunt Video
- Posts: 2561
- Joined: May 4th, '11, 19:03
- Location: Former caretaker S/V Bali Ha'i 1982 CD 25D; Hull 69 and S/V Tadpole Typhoon Week
Re: Re-Core Cockpit Sole
Jeff:
Unfortunately, I cannot offer any suggestions, etc. on your recoring job.
I do have a few questions about the photos you posted. Your photos fit the screen and are not too large like some. Also, they show up right away on my computer screen. Some photos that others post, for reasons I do not understand, take a long time to show up on my computer screen. Not sure if it is my computer or something else. Anyways,
1. What camera did you use
2. What website (?), program (?), or software (?) did you use to post the photos
3. Are there any special settings or formats that you used to post the photos
I am thinking about making a New Year's resolution to finally learn how to post a simple photo on this board. It may cost me what little sanity I have left but I am thinking of trying again to do it.
Thank you.
I wish all on this board a Safe and Happy Thanksgiving.
Unfortunately, I cannot offer any suggestions, etc. on your recoring job.
I do have a few questions about the photos you posted. Your photos fit the screen and are not too large like some. Also, they show up right away on my computer screen. Some photos that others post, for reasons I do not understand, take a long time to show up on my computer screen. Not sure if it is my computer or something else. Anyways,
1. What camera did you use
2. What website (?), program (?), or software (?) did you use to post the photos
3. Are there any special settings or formats that you used to post the photos
I am thinking about making a New Year's resolution to finally learn how to post a simple photo on this board. It may cost me what little sanity I have left but I am thinking of trying again to do it.
Thank you.
I wish all on this board a Safe and Happy Thanksgiving.
Fair winds,
Roberto
a/k/a Sea Hunt "The Tadpole Sailor"
CDSOA #1097
________________________________
"I wish to have no Connection with any Ship that does not Sail fast for I intend to go in harm's way." Captain John Paul Jones, 16 November 1778, as quoted in Naval History and Heritage Command, http://www.history.navy.mil
Roberto
a/k/a Sea Hunt "The Tadpole Sailor"
CDSOA #1097
________________________________
"I wish to have no Connection with any Ship that does not Sail fast for I intend to go in harm's way." Captain John Paul Jones, 16 November 1778, as quoted in Naval History and Heritage Command, http://www.history.navy.mil
Re: Re-Core Cockpit Sole
Robert,
thanks for the encouragement!
The camera is a Canon ELPH340HS. It's cheap enough that it's not a disaster if it falls in the water but it is much better response and zoom than a smart phone camera, although those are darn good!
I use http://www.smugmug.com for photos. They charge ~40/yr but it is set up for professionals so it doesn't crash, is fast, works with Apple, works with Windows, sort of works with Android and offers unlimited storage of full resolution images. Since I share a lot pf photos with family it's worth the money to not have to mess around with sites that behave erratically. A couple people here, including I think Carl Thunburg, has a problem where their work firewall thought it was a blog and did not allow access.
Some of those pictures I moved to my website although I had to reduce the resolution as I don't pay for much storage there. The website is jbenagh.com but I don't put much there. It has been hosted by several providers over the years, all pretty inexpensive. I started off with that as a hobby for my inner geek since I liked writing low level website code to see how it worked.
Including a photo is pretty easy for me: above there is an icon that says "Img"; click on it and you get a tag "[img][\img]. Paste a link to the picture between the tow and you will be all set. To get the link to the picture, right click (in Firefox or Chrome), select the .jpg link, and paste that puppy between the braces; you should be all set. Just don't paste the html link or you will be disappointed.
Jeff
thanks for the encouragement!
The camera is a Canon ELPH340HS. It's cheap enough that it's not a disaster if it falls in the water but it is much better response and zoom than a smart phone camera, although those are darn good!
I use http://www.smugmug.com for photos. They charge ~40/yr but it is set up for professionals so it doesn't crash, is fast, works with Apple, works with Windows, sort of works with Android and offers unlimited storage of full resolution images. Since I share a lot pf photos with family it's worth the money to not have to mess around with sites that behave erratically. A couple people here, including I think Carl Thunburg, has a problem where their work firewall thought it was a blog and did not allow access.
Some of those pictures I moved to my website although I had to reduce the resolution as I don't pay for much storage there. The website is jbenagh.com but I don't put much there. It has been hosted by several providers over the years, all pretty inexpensive. I started off with that as a hobby for my inner geek since I liked writing low level website code to see how it worked.
Including a photo is pretty easy for me: above there is an icon that says "Img"; click on it and you get a tag "[img][\img]. Paste a link to the picture between the tow and you will be all set. To get the link to the picture, right click (in Firefox or Chrome), select the .jpg link, and paste that puppy between the braces; you should be all set. Just don't paste the html link or you will be disappointed.
Jeff
Re: Re-Core Cockpit Sole
Roberto,Sea Hunt Video wrote:I am thinking about making a New Year's resolution to finally learn how to post a simple photo on this board. It may cost me what little sanity I have left but I am thinking of trying again to do it.
Thank you.
I wish all on this board a Safe and Happy Thanksgiving.
When you decide to give it a try again just let us know how you are coming along and I'm sure several of us can help you. With a tablet like my iPad it couldn't be simpler but a desk or laptop involves several steps. These are the things which are intuitive for grandchildren but are a skill which must be learned by mature individuals. I used the "Sandbox" section for all my initial attempts just so I didn't post all my "testing" for the general population to contend with. You possess all the necessary skills, you just need to get the sequence of steps to "click" in your noggin
Jim Walsh
Ex Vice Commodore
Ex Captain-Northeast Fleet
CD31 ORION
The currency of life is not money, it's time
Ex Vice Commodore
Ex Captain-Northeast Fleet
CD31 ORION
The currency of life is not money, it's time
Re: Re-Core Cockpit Sole
Great photos Jeff,
I'm looking forward to following your progress. On MOON DANCE in light winds I can feel and hear a slight noise from movement of the pedestal forward and aft. Everything underneather the cockpit sole is tight so I'm guessing it may be a partially rotted balsa core. That is a project for another winter however. This winter I'm tackling replacing the bow sprit and steel bow support. The bow sprit is off (in many many pieces) and wow a lot more rot then I had imagined. The steel section under the bow is quite rusted too. I will post pictures under a separate post for all to see. I'm thinking of going with the G10 as a replacement for the steel support as one other owner has done but that decision is a ways off.
Good luck on your project!
Keith
I'm looking forward to following your progress. On MOON DANCE in light winds I can feel and hear a slight noise from movement of the pedestal forward and aft. Everything underneather the cockpit sole is tight so I'm guessing it may be a partially rotted balsa core. That is a project for another winter however. This winter I'm tackling replacing the bow sprit and steel bow support. The bow sprit is off (in many many pieces) and wow a lot more rot then I had imagined. The steel section under the bow is quite rusted too. I will post pictures under a separate post for all to see. I'm thinking of going with the G10 as a replacement for the steel support as one other owner has done but that decision is a ways off.
Good luck on your project!
Keith
Re: Re-Core Cockpit Sole
Made some progress today. Here's where I started; steering cables out, pedestal off:
Then I got ready to remove the stuffing box by removing everything on the rudder shaft. First the quadrant, then the upper shaft support then the weldment pulled off just by light prying with a screwdriver. Got everything except the box. Left the boat with it thoroughly doused in PB Blaster:
Sorry, I took these pictures from opposite sides. I forgot where I started.
I also tested using the oscillating tool cutting the sole fiberglass. Bosch carbide blades (OSC114-2) worked great! Cuts fast with very little dust that just vacuums up and a nice, thin cut.
Jeff
Then I got ready to remove the stuffing box by removing everything on the rudder shaft. First the quadrant, then the upper shaft support then the weldment pulled off just by light prying with a screwdriver. Got everything except the box. Left the boat with it thoroughly doused in PB Blaster:
Sorry, I took these pictures from opposite sides. I forgot where I started.
I also tested using the oscillating tool cutting the sole fiberglass. Bosch carbide blades (OSC114-2) worked great! Cuts fast with very little dust that just vacuums up and a nice, thin cut.
Jeff
Re: Re-Core Cockpit Sole
A year ago I was wandering around beneath my cockpit sole looking for things to unnecessarily complicate my life when I decided it might be a good time to replace the packing in my rudder shaft stuffing box. I got as far as loosening the retainer ring and lifting the stuffing box nut (where the packing resides) before realizing the shaft key extended so far that I didn't have the room to slide it up the shaft enough to gain access to the packing.
Since there was no leak involved I just tightened everything back up and left the scene of the crime. There are times when I feel like getting my Dremel into the act and just grinding a section of the key down (which would have no effect on its function) so I can slide the nut far enough to to have access to the packing, but I have, so far, resisted the urge.
Since there was no leak involved I just tightened everything back up and left the scene of the crime. There are times when I feel like getting my Dremel into the act and just grinding a section of the key down (which would have no effect on its function) so I can slide the nut far enough to to have access to the packing, but I have, so far, resisted the urge.
- Attachments
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- Rudder shaft stuffing box
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- Damn key in the way
- image.jpeg (1.91 MiB) Viewed 2044 times
Jim Walsh
Ex Vice Commodore
Ex Captain-Northeast Fleet
CD31 ORION
The currency of life is not money, it's time
Ex Vice Commodore
Ex Captain-Northeast Fleet
CD31 ORION
The currency of life is not money, it's time
Re: Re-Core Cockpit Sole
Jim,
For me the key came right out when I loosened the quadrant. I can see why you might not want to remove that just to change the stuffing but it seems that changing stuffing and steering cables at the same time would make sense.
Jeff
For me the key came right out when I loosened the quadrant. I can see why you might not want to remove that just to change the stuffing but it seems that changing stuffing and steering cables at the same time would make sense.
Jeff
Re: Re-Core Cockpit Sole
Jim,
Did you try to tap the key back up with a drift pin. It seem a bit odd that it would be that long. Possibly it has worked it's way down over time.
Food for thought.
Keith
Did you try to tap the key back up with a drift pin. It seem a bit odd that it would be that long. Possibly it has worked it's way down over time.
Food for thought.
Keith
Re: Re-Core Cockpit Sole
I made some more progress today.
During the pre-purchase survey the surveyor noticed some moisture around the pedestal and the emergency tiller opening. So, before the 2011 season, on the recommendation of the surveyor I removed the emergency tiller cover, routed out the wood material about 1/4 in and filled with thickened epoxy. Apparently it didn't help much since the putty knife came out covered in wet wood! Here's a kind of blurry shot into the emergency tiller opening:
I cut around the entire cockpit 1 1/2 inches in from where the sole falls off. Then I gently pried, first with the edge of a putty knife (which just happened to exactly fit in the cut made by the oscillating tool). Then I moved to a pry bar backed up by the putty knife:
I left a foot of the aft sole intact for the time being to provide a platform to work from. It was a lot less delaminated than the rest of the sole judging from its firmness and lack of checking. This also allowed me to pull the entire top laminate away; when it was still held on by the aft most piece I could not get it.
With the prybar, the best technique I found was to pry slowly, listening to the sound of the glass pulling away from the wood. If I moved too fast the glass began to crack which would make it unusable for the repair. After a lot of prying I got the top layer off:
You can see that there is 1/2 in plywood around the steering pedestal and guard; a 12in square of 3/4 in plywood centered on the forward end of the cockpit; two 3/8 in pieces of pretty random shapes (more to come) to the sides of that one; and the rest is all balsa in various states of decay. This was a little surprising as I had always thought the cockpit used all plywood for the core material. I guess since it is plywood in many of the spots one might see or drill into it's not too surprising.
There was a diagonal line of cured resin along the aft end of the starboard 3/8 in piece. This was really well affixed to the top of the sole and provided a hard point so when prying it loose caused some cracking in the top piece as I removed it. As I cut with the oscillating tool I noticed there were some spots that were tougher; all of these turned out to be places where there was solid resin instead of wood. Since I plan to replace the entire core it was OK to cut into the core taking care to not cut into the lower laminate layer.
Since I think I will have to replace the top fiberglass piece and since they were not delaminated I cut the aft square in half and removed both pieces with the same putty knife and prybar trick. The balsa here was wet but not delaminated. I guess since the aft end is higher than forward where the scuppers are, the water generally flowed to the bow.
All the exposed wood was SOAKED, dripping with water including the plywood. I got on it with the putty knife, occasionally some cheap chisels and then a good scraper. After all that I ended up with this:
The after end is at the top of the photo and looks like good fiberglass. All the rest is blackened from decayed balsa or the residue of the plywood pieces. I still need to get the remaining wood out of the edges but I will need a better work platform; it's just too hard to balance on the cockpit seats.
After learning what was inside I may revise my plan for the recore. I think I will stick with the Coosa for the areas where there was plywood but expand it to cover the space around the emergency tiller access. I will use one of the foam based balsa replacements for the rest since the factory balsa was plenty strong and there is no need to add extra weight.
Jeff
During the pre-purchase survey the surveyor noticed some moisture around the pedestal and the emergency tiller opening. So, before the 2011 season, on the recommendation of the surveyor I removed the emergency tiller cover, routed out the wood material about 1/4 in and filled with thickened epoxy. Apparently it didn't help much since the putty knife came out covered in wet wood! Here's a kind of blurry shot into the emergency tiller opening:
I cut around the entire cockpit 1 1/2 inches in from where the sole falls off. Then I gently pried, first with the edge of a putty knife (which just happened to exactly fit in the cut made by the oscillating tool). Then I moved to a pry bar backed up by the putty knife:
I left a foot of the aft sole intact for the time being to provide a platform to work from. It was a lot less delaminated than the rest of the sole judging from its firmness and lack of checking. This also allowed me to pull the entire top laminate away; when it was still held on by the aft most piece I could not get it.
With the prybar, the best technique I found was to pry slowly, listening to the sound of the glass pulling away from the wood. If I moved too fast the glass began to crack which would make it unusable for the repair. After a lot of prying I got the top layer off:
You can see that there is 1/2 in plywood around the steering pedestal and guard; a 12in square of 3/4 in plywood centered on the forward end of the cockpit; two 3/8 in pieces of pretty random shapes (more to come) to the sides of that one; and the rest is all balsa in various states of decay. This was a little surprising as I had always thought the cockpit used all plywood for the core material. I guess since it is plywood in many of the spots one might see or drill into it's not too surprising.
There was a diagonal line of cured resin along the aft end of the starboard 3/8 in piece. This was really well affixed to the top of the sole and provided a hard point so when prying it loose caused some cracking in the top piece as I removed it. As I cut with the oscillating tool I noticed there were some spots that were tougher; all of these turned out to be places where there was solid resin instead of wood. Since I plan to replace the entire core it was OK to cut into the core taking care to not cut into the lower laminate layer.
Since I think I will have to replace the top fiberglass piece and since they were not delaminated I cut the aft square in half and removed both pieces with the same putty knife and prybar trick. The balsa here was wet but not delaminated. I guess since the aft end is higher than forward where the scuppers are, the water generally flowed to the bow.
All the exposed wood was SOAKED, dripping with water including the plywood. I got on it with the putty knife, occasionally some cheap chisels and then a good scraper. After all that I ended up with this:
The after end is at the top of the photo and looks like good fiberglass. All the rest is blackened from decayed balsa or the residue of the plywood pieces. I still need to get the remaining wood out of the edges but I will need a better work platform; it's just too hard to balance on the cockpit seats.
After learning what was inside I may revise my plan for the recore. I think I will stick with the Coosa for the areas where there was plywood but expand it to cover the space around the emergency tiller access. I will use one of the foam based balsa replacements for the rest since the factory balsa was plenty strong and there is no need to add extra weight.
Jeff