Through hull fish Finder for depth with verifier accuracy gauge called keel for those locations less than 8 feet deep. For speed take a moment during slack tide/current using your GPS against the amount of wake that you create from 3 to 12 mph to improve your ability to estimate speeds by eye. It is unlikely you will be harassed by a multitude of Slalom skiers for rides and you'll not be replacing repairing through hulls.
Seacock Quality... Replace?—Currently on the hard.
- Thread starter testingthewaters91
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I see. How about the 'shoot through hull' transducer? I already broke the previous transducer housing and ordered fiberglass to glass up the two thru hulls.
I had two “shoot thru“ depth transducers on my previous boat, a 1988 Hunter 33.5.
The original transducer, factory installed, was bedded in polyester resin at aft 1/3 of boat at entrance to aft berth. At some point, I replaced instruments & installed new transducer beneath V berth. Used method published in Sail magazine. Glassed a bell shaped PVC adapter to hull internal surface, filled the adaptor with mineral oil, & screwed the transducer into the adaptor. Worked well; no leaks.
The original transducer, factory installed, was bedded in polyester resin at aft 1/3 of boat at entrance to aft berth. At some point, I replaced instruments & installed new transducer beneath V berth. Used method published in Sail magazine. Glassed a bell shaped PVC adapter to hull internal surface, filled the adaptor with mineral oil, & screwed the transducer into the adaptor. Worked well; no leaks.
This will be my way forward. No need for the two monstrous 2" holes in the bottom of my boat, even if bedded carefully by me.
Will glass them up and use the shoot through hull transducer.
I would glass over the holes, use the shoot-through transducer for depth, and get a GPS for speed (at least SOG). So no holes in the hull for transducers 
Greg
Greg
At first I was scared of the glass work, but it seems like I have no choice. I've been studying up on how to glass the holes. I bought 17oz fiberglass cloth and West System Epoxy. It should be strong enough.I would glass over the holes, use the shoot-through transducer for depth, and get a GPS for speed (at least SOG). So no holes in the hull for transducers
Greg
I would strongly suggest reading the Gougeon Bross manual on basic frp repairs. I believe it can be d/l from their web site. A cheap angle grinder will make it easy to establish the slope around the holes, and then follow the instructions on cutting and preparing the layers of glass. If you have not worked with epoxy before, mix up a small ("one pump") batch and do some sacrificial lay up on some test pieces. Do this on a piece of Saran wrap or similar.) Once you see how long you have for the initial cure to start, you will start to gain confidence.
The irony is that you will only make mistakes after you first gain some initial confidence, and then also find that mistakes in glassing can always be ground out and better work can be done!
There are few real "secrets" to this. Just have a good rough surface to bond to (60 grit is good) and clean it with acetone first. Use vinyl gloves and wear old clothing like you would wear for painting. Actually, for general grinding, glassing, and painting I like an inexpensive "tyvek" (or similar) disposable suit. Those are not expensive and can last a long time if you are careful not to rip out a zipper.
17 OZ? Wow. That's heavy duty!
Good luck!
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Thanks for the thoughtful response.I would strongly suggest reading the Gougeon Bross manual on basic frp repairs. I believe it can be d/l from their web site. A cheap angle grinder will make it easy to establish the slope around the holes, and then follow the instructions on cutting and preparing the layers of glass. If you have not worked with epoxy before, mix up a small ("one pump"0 batch and do some sacrificial lay up on some test pieces. Do this on a piece of Saran wrap or similar.) Once you see how long you have for the initial cure to start, you will start to gain confidence.
The irony is that you will only make mistakes after you first gain some initial confidence, and then also find that mistakes in glassing can always be ground out and better work can be done!
There are few real "secrets" to this. Just have a good rough surface to bond to (60 grit is good) and clean it with acetone first. Use vinyl gloves and wear old clothing like you would wear for painting. Actually, for general grinding, glassing, and painting I like an inexpensive "tyvek" (or similar) disposable suit. Those are not expensive and can last a long time if you are careful not to rip out a zipper.
17 OZ? Wow. That's heavy duty!
Good luck!
I went with 17 oz cloth because I’m dealing with two 2-inch through-hull patches, and I want to ensure maximum strength and durability. From what I’ve read and heard, 17 oz biaxial provides exceptional structural integrity, often reducing the number of layers needed compared to lighter weights. I tend to err on the side of caution, especially below the waterline — overbuilding gives me peace of mind.
I had to grind down about 1/4" into the hull laminate to get the old flange out of mine. I started out with a thin "wet out" of thickened epoxy with high density filler because I found some voids in the laminate. Then had to build the laminate back up to about 1/2" using 2 layers of CSM and 6 layers of 10 oz cloth. Then I bonded to G10 backing plate to that with milled fiber ("kitty hair").
It was my first time also and was a little apprehensive. A couple suggestions:
Use what comes out when you prime the mini-pumps as your first experiment. It's not exactly proportioned but will give you a feel of what to expect in the curing process. Pour it out on a piece of plastic and test the consistency as it goes through the curing process.
Pre-cut everything so you don't waste time while it's curing on you.
Make certain the cloth is fully wetted out (translucent) but don't leave puddles of resin. I used a cut off chip brush and it made it easy to wet it out and move the cloth a little should you "miss". Use a spreader to gently work excess resin out as you go.
No matter what you do, epoxy seems to get everywhere. Disposable clothes (and gloves) are very important. Some plastic sheeting around where you're working helps a lot.
And by all means, read the West Systems instruction manual (around here, just about everyone who sells West Systems epoxy has free copies for the taking) and their "Fiberglass Boat Repair & Maintenance" book.
Just one newbie's take.
It was my first time also and was a little apprehensive. A couple suggestions:
Use what comes out when you prime the mini-pumps as your first experiment. It's not exactly proportioned but will give you a feel of what to expect in the curing process. Pour it out on a piece of plastic and test the consistency as it goes through the curing process.
Pre-cut everything so you don't waste time while it's curing on you.
Make certain the cloth is fully wetted out (translucent) but don't leave puddles of resin. I used a cut off chip brush and it made it easy to wet it out and move the cloth a little should you "miss". Use a spreader to gently work excess resin out as you go.
No matter what you do, epoxy seems to get everywhere. Disposable clothes (and gloves) are very important. Some plastic sheeting around where you're working helps a lot.
And by all means, read the West Systems instruction manual (around here, just about everyone who sells West Systems epoxy has free copies for the taking) and their "Fiberglass Boat Repair & Maintenance" book.
Just one newbie's take.