'85 Sierra 16.5' Fiberglass - Floor / Transom / New Layout

Baxterdmutt

Cadet
Joined
Aug 16, 2024
Messages
10
I’m in the process or redoing my floor as well. On mine I found that the initial design was flawed. They used a void under the bottom of the centre transom as a water drain from the front of the boat to the back bilge. That void rotted the transom from the bottom up. So this time I fibreglassed a tube down the centre and then fibreglassed the transom to the hull like it was before. Water can never touch the bottom of that transom again!
I also found that they divided the front 1/3 hull from the back and just used plywood (un-fiberglassed or very poorly fibreglassed). That meant that water would not make it to the centre transom void and instead leaked into the main part of the hull and got the foam all wet. Now that divider is well fibreglass and water can only get from the front 1/3 to the back bilge, through the centre transom void (with tube).
Just some thoughts to consider from a novice. I’m sure there is a better way but I’m mainly just explaining how it got all wet under the foam.
 

Twhjelmgren28

Petty Officer 3rd Class
Joined
May 31, 2016
Messages
85
I’m in the process or redoing my floor as well. On mine I found that the initial design was flawed. They used a void under the bottom of the centre transom as a water drain from the front of the boat to the back bilge. That void rotted the transom from the bottom up. So this time I fibreglassed a tube down the centre and then fibreglassed the transom to the hull like it was before. Water can never touch the bottom of that transom again!
I also found that they divided the front 1/3 hull from the back and just used plywood (un-fiberglassed or very poorly fibreglassed). That meant that water would not make it to the centre transom void and instead leaked into the main part of the hull and got the foam all wet. Now that divider is well fibreglass and water can only get from the front 1/3 to the back bilge, through the centre transom void (with tube).
Just some thoughts to consider from a novice. I’m sure there is a better way but I’m mainly just explaining how it got all wet under the foam.
That sounds messy! My stringer goes right down the keel of the boat but I couldn't actually tell if they fiberglassed the 2 ends or not. It didn't look like they had fiberglassed the front end of the stringer which could've been my water entry point - The boat is nearing 40 years old so it had a really good run with the original installation. I'll have to figure out how I'm going to rebuild to minimize potential water entry just like you.


Keep grinding up the sides, about 8" past where you will tab
Appreciate the response! I do plan on going all the way up the sides to get the carpet residue out so I should be able to hit that 8" recommendation.

I'm actually more curious about how deep to grind. For example, in the 3 most recent pictures I posted, do I need to grind the areas around those spots deeper to match those blemishes (?) or are those areas I should plan on bulding up with resin / mat in the future and stop grinding in those spots. Note, the first two pictures are the floor and the third is the transom. My goal was to get one even level of grinding without going too far...
 

SlipperyOar

Petty Officer 3rd Class
Joined
Apr 12, 2024
Messages
92
I've been rolling with the grinding. I'm about 8 hours in and have a lot to do yet. I'm back to the age-old question: How far do I grind?

Here is a couple pictures from each end of the boat:





I have specific questions about the following 3 areas - In the first, it looks like I've ground to some fabric - not sure if that's the fiberglass mat or something else? Do I need to grind through that in that section of the boat?





The next area, I think I just ground through 1 layer, down to the next. Again, should I do that for the entire section of the boat or is that just an area I should build back up when fiberglassing?





My final question relates to the transom. I've ground quite a ways through the transom already and I'm still coming across some of these smaller voids (??) - In other words, I'm still not smooth to a singl layer but I don't want to grind all the way to the gel coat. I've already taken quite a bit off (though I still have about 8mm of thickness or so).





***Note: The above-images were posted through Imgur since the server is still having issues. Let me know if you can't see them.

I will undoubtedly have more questions as I continue the grinding process and all help is appreciated!
Completely unrelated from your work, how are you uploading images right now? I’ve been attempting through iboats with no success. How do I post images with imgur?
 

todhunter

Canoeist
Joined
Sep 15, 2020
Messages
1,311
Completely unrelated from your work, how are you uploading images right now? I’ve been attempting through iboats with no success. How do I post images with imgur?
Upload pics to a 3rd party hosting site. Copy the URL for the first pic. On iBoats, click the pic icon (looks like a square with mountains). Click the chain icon (not the upload icon), then paste the URL for the first pic. Repeat for remaining pics.
 

Twhjelmgren28

Petty Officer 3rd Class
Joined
May 31, 2016
Messages
85
Completely unrelated from your work, how are you uploading images right now? I’ve been attempting through iboats with no success. How do I post images with imgur?

From the respect of Imgur, you upload your photos to a post on the imgur site. You then click into your post which should open your album of photos. There are 3 dots in the corner of each picture. For every picture you want to put on the forum, click the 3 dots, then click "Get share links." Copy the link under "BBCode (forums)". Then when posting, you use that link in the exact manner tod posted above. Click the mountain icon, click the link icon, post that BBCode (forums) link into the URL window.
 
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