Weld Mount tabs for securing transducer and cables?

ferret30

Anyone thought of using these for mounting gear on the transom? I'm going to be replacing my sounder setup and filling/covering some less than ideal holes, and I came across these:

http://www.weldmountsystem.com/products/fasteners/stainless_studs.html

It seems like you could mount 3 or 4 of these to the lower transom, then use them to secure an HDPE block for mounting the transducer. No sealant, epoxy, etc. needed. They also have cable guides that work the same way:

http://www.weldmountsystem.com/products/fasteners/wireties.html

The main problems I'd imagine are getting them to work when the lower transom has bottom paint, and removing them (no info on that!). Also, if they're so strong I'd hate to see what happens to the FG lamination if something got snagged and pulled hard on the mount!

thataway · Posted: Thu Dec 01, 2011 8:57 pm Post subject:

You still have to fill transom screw holes from the previous transducer. What happens when you need to change transducers with different spacing? What happens when the transducer has to moved down or up for best results? I like the Starboard, because you can put multiple screw holes in it, and move the transducer .

Yes, you would have to go back to the bare glass/gel coat, and probably coat it with epoxy for best adhesion. Also the bases look large. I would stick to tried methods.

ferret30 · Posted: Thu Dec 01, 2011 9:04 pm Post subject:

Bob, actually meant you'd use them to mount a piece of HDPE/Starboard as you've proposed before. You could also replace the piece if necessary since it would be held on by lock nuts.

But it isn't great that it could damage the outer layer of fiberglass if the mounts got hit/bent, and not being able to remove them is of course an issue.

thataway · Posted: Thu Dec 01, 2011 9:32 pm Post subject:

You would have to do some destructive testing to see how well this adheres to the glass--my guess is that it would be hard to pull the glass apart on just a shear hit. I have pulled glass apart when removing an item bedded with 5200--so it depends on how well the adhesive bonds. Even 5200 can bond well in many application, but occasionally it will not. In that case where I had started out using a hot wire to remove the 5200, I finally ended up using a debond.

The same effect could be achieved with epoxy adhered large base studs. Some of us have put blocks of wood on the inside of the boats with epoxy, and the adhesion is very good, if done properly.

In the back of my mind, I think we talked on this forum or another about some similar adhesive system in the past.

ferret30 · Posted: Thu Dec 01, 2011 9:40 pm Post subject:

If I had more confidence in my skills I'd probably have done it by now. But getting epoxy to completely fill a void in a vertical surface (especially with undercutting) seems tricky. But it would have to be better than what I've got now. It's amazing that installers are still just gooping up screws and driving them in to the transom and that's it!

The thing that made me consider this approach is that the guy that did my deck/cockpit hole repair work this summer (and did a fantastic job) said he'd grind/glass/gelcoat over the transducer holes (5 of them including the cable guides) for $100, so I could start fresh. It was just an option I was considering.

I'm probably going to get a Garmin Echo 100 to replace my enormous Humminbird fish finder that's blocking the middle window, so that's why I'm thinking through this stuff right now.

starcrafttom · Posted: Thu Dec 01, 2011 10:40 pm Post subject:

that new echo 100 looks like a good unit for 80 bucks. what hummingbird unit do you have now?

ferret30 · Posted: Fri Dec 02, 2011 12:23 am Post subject:

Tom, it's a Humminbird LCR8000 according to the manual (the boat isn't here). You can have it if you want!

I just thumbed through the manual and here's what it says for mounting instructions:

Mark and drill the three 9/64” dia. holes as shown on the template. Attach the metal bracket using the three #10 self threading screws supplied. Be sure to align the holes so that they are centered vertically in the three slots found in the bracket. It is important to use a silicone sealant between the screwhead and bracket in order to prevent leaking.

I can't believe the only recommended sealant strategy is to use some silicone between the screwhead and the bracket. What?! I felt around the bracket last time I was working on the boat and it does feel and look like clear silicone! I really need to do something about these transom holes...