plugging holes...

scurvy · #1 05-15-2007

Hi there,

We are considering removing our fairing block and transducer and replacing with an "In-Hull" model. What is the best way to repair the hole after doing this? I have seen a few methods, but would love pictures or words of advice from someone with first hand knowledge of such a procedure!

Thanks Everyone!

txmatt · #2 05-15-2007

When I did mine I just sanded the inside of the hull around it then put down a few layers of glass, let that set up and then faired it from the outside using thickened epoxy. Very easy and my boat hasn't sunk yet.

On a seperate but related note, I'm still trying to get my in hull transducer working.

scurvy · #3 05-15-2007

On a seperate but related note, I'm still trying to get my in hull transducer working.[/QUOTE]

What seems to be the problem? Is there air space between the unit and the hull? How did you choose to mount it?

scurvy · #4 05-15-2007

Quote:

Originally Posted by txmatt

On a seperate but related note, I'm still trying to get my in hull transducer working.

What seems to be the problem? Is there air space between the unit and the hull? How did you choose to mount it?

txmatt · #5 05-15-2007

Quote:

Originally Posted by scurvy

What seems to be the problem? Is there air space between the unit and the hull? How did you choose to mount it?

I attempted a mount with a putty-type epoxy which is clearly not going to work, so I removed it before it set up completely. I'm going to try to sand the area smooth again, get it clean and use west expoxy thickened with high density filler.

I'm trying to put it in the bottom of my keel, which I'm afraid may be too thick to get a good reading through, but it would be really nice to have the depth reading be the depth under the keel and on the centerline. I did get it to work when I was initially testing it with a little water in there and applying pressure to the transducer.

sailingdog · #6 05-15-2007

Quote:

Originally Posted by txmatt

When I did mine I just sanded the inside of the hull around it then put down a few layers of glass, let that set up and then faired it from the outside using thickened epoxy. Very easy and my boat hasn't sunk yet.

On a seperate but related note, I'm still trying to get my in hull transducer working.

First, you really need to patch the hole that the previous transducer was in with glass from both sides... grinding it out to about a 12-to-1 bevel... and then filling it by laminating glass over it from both sides... doing it just from the inside is asking for a problem later on IMHO.

As for your in-bilge shoot-through-the-hull transducer, you might want to use the PVC pipe and mineral oil method that I normally suggest. It seems to work far better than using putty or epoxy from what I've seen.

T34C · #7 05-15-2007

Mounting the transducer should be easy. Sand area just larger than the transducer smooth inside hull where you want to mount it. apply a nice big glob of polysulfite caulk to transducer and press firmly into place. Make sure to push down firmly removing any air in the caulk. Let dry. (You may need to tape the transducer in place until it dries.) The polysulfite dries solid enough to give an accurate reading and yet can be removed later if needed. The PVC pipe and mineral oil method does work well, but why do all that if you don't have to.

Most modern depth sounders have the ability to show the depth under the keel reguardless of where you mount the transducer. There should be a setting called something like "keel off-set" that allows you to input the difference in depth between where the transducer is mounted and the bottom of the keel. I personally prefer to know the true depth of the water not depth under keel.

scurvy · #8 05-16-2007

Polysulfite sounds like the trick! I will look into it!
Thanks T34C and all who have contributed!

sailingdog · #9 05-16-2007

Scurvy-

Just be aware that Polysulfide-based sealants tend to attack most plastics... and if the transducer has any plastic in it...it probably will not like the polysulfide sealant or play nice with it.

T34C · #10 05-16-2007

Quote:

Originally Posted by sailingdog

Scurvy-

Just be aware that Polysulfide-based sealants tend to attack most plastics... and if the transducer has any plastic in it...it probably will not like the polysulfide sealant or play nice with it.

While that is a possiblity, my current unit (with plastic puck transducer) is currently mounted in its second boat with no problems. I still have an older unit that was mounted in a previous boat the same way for several years and shows no signs of affect from the polysulfite.