Side Imaging Transducer Mounting Plate

[EZM]

Looking for ideas, experiences good and bad, right or wrong, for anyone who has a SI (side imaging transducer) mounted on thier transom.

I want to learn from YOUR mistakes .... and drill less holes in my boat. lol.

I also see quite a few guys using a mounting plate (looks like a rectangular piece of PVC plywood maybe) on the transom of the boat where they have ended up attaching thier transducer bracket.

I assume this is so you are drilling and sealing up only two holes in your boat, (the ones used to mount the plate), as opposed to right into your boat.

I will probably be drilling 3 holes the first time, 3 holes again when I have to move the transducer, and then another 3 holes to adjust it again ... lol.

I will probably sink the boat.

One other minor question - the PVC board - Is it just simply "off the shelf at Home Depot" or what?

Comments, ideas and stories would be aprechiated.

[EZM]

I should mention this is a SI (side image) transducer which is signifigantly more sensitive to interference, poor returns, being blocked by the outboard, etc..

The SI shoots a beam 86 degrees out each side of the transducer (almost straight accross the surface of the water) and end straight down. One on the right and another on the left.

The giant "soap bar sized" SI transducers must be carefully mounted from what I understand.

It also needs to be mounted slightly, but not less than 15", to the right side of the transom as the prop spins clockwise and creates less disturbance on the right hand side.

This is the reason for my question.

Anyone played this game before????

The Humminbird forum is educating me a little, but also making me nervous as the dealer seems to have no experience with this relatively new technology. I think I'd rather screw it up myself .....

[Walleyedude]

The most common "PVC" board is called King Starboard. Look for it at a specialty plastics shop, I don't think you'll find it on the shelf at Home Depot.

Also, if it were me, I would avoid putting any holes in your boat below the water line. I wouldn't screw it on at all, just grab some PL Premium or something similar and simply glue the board to your transom. It really is strong as nails, it won't go anywhere. Once you've done that, you can you can fill the board full of holes mounting and remounting transducers to your hearts content lol.

Here's a video of mounting a Lowrance DI/SI transducer to help you out -

http://www.youtube.com/watch?v=XmR500kNNz8

It's not rocket science, just get it as accurate as you can and you'll be good to go.

[EZM]

Great video - thanks.

Are you sure the PL will hold on my tin boat? The mounting plates, at least all the one I've seen, seem to be screwed in.

My assumption is, based on what I've seen, you should be able to effectively seal the two little holes with marine silicone. But, like you, putting a hole in my new boat is not my favorite idea.

On the other hand, a failure of adhesion at high speed could be very expensive for my electronics and prop.

Have you had any issues just gluing the plate on?

The Lowrance video is good, and applies in general, except I'm running Humminbird which is only one fully integrated transducer instead of the two for the Lowrance.

The Humminbird units put everything into one giant transducer the size of a bar of soap and, from what I've heard, it needs to be perfect.....so we may need to adjust it a few times.

The two helm units (798ci HD SI) units with be ethernet connected to share the transom mount transducer. So only one will be attached at the transom.

I ordered the "soon to available" MK Terrova US2/80/i-Pilot Link (the "link" is the new part) and running the bow mounted Humminbird 596 on the Terrova's built in transducer. Hope that works well, if not, I will add another transducer to the transom if needed. Apparently the US2 (built in transducer) in the MK works great. I guess we will see .......

Either way ......... thanks for the info .........

[Vic Carrao]

I have 2 jet boats with the SI transducer, both are aluminum and have mounting plates on transome. I have had an issue with breaking the transducer when backing off the trailer,so I custom designed a box to mount the transducer, then I mount the box to transome. You might not have this issue unless you have lots of Horse Power like mine. I wrote an article on jet boat maintenance you might find useful. http://www.guidebc.com/images/jetboatmaintenance_alumboxside_240w.jpg

http://www.guidebc.com/images/jetboatmaintenance_alumboxunder_135h.jpg

Article at - http://www.guidebc.com/articles/jetboatmaintenance.asp

[huntsfurfish]

I screwed and glued my mounting plates to the transom. I mounted it(SI) where I had an existing transducer - got lucky was perfect. Ill look to see if I have any pics of it.:)

[EZM]

Vic,

I won't be pushing the power or bumping the stumps like you would with your jet. If I'm crashing my transducer, I have bigger issues ..... lol. Its going on a new 1800 Tyee with a 150 Honda - no comparison to your jets.

I was, however, thinking about getting someone who could weld / fabricate aluminum and make up a bracket. This would ensure the boat would be watertight and the transducer would be positioned correctly. On the other hand, it may not even be worth it and it could be a waste of money.

huntsfurfish,

If you got some photos, It would be cool to see. Just trying to get an idea on what works best. The more I see, the better off I will be.

[EZM]

The most common "PVC" board is called King Starboard. Look for it at a specialty plastics shop, I don't think you'll find it on the shelf at Home Depot.

Also, if it were me, I would avoid putting any holes in your boat below the water line. I wouldn't screw it on at all, just grab some PL Premium or something similar and simply glue the board to your transom. It really is strong as nails, it won't go anywhere. Once you've done that, you can you can fill the board full of holes mounting and remounting transducers to your hearts content lol.

Here's a video of mounting a Lowrance DI/SI transducer to help you out -

http://www.youtube.com/watch?v=XmR500kNNz8

It's not rocket science, just get it as accurate as you can and you'll be good to go.

Good info - thanks. I feel the same way about holes. If they can be avoided I would prefer that for sure. I'm just not sold on the connection glue will have on Aluminum to PVC as the properties are substantially different and I could see it de-laminating over time.

[bobalong]

I have my SI on my pontoon boat. The bracket for the transducer was on the left toon, so I mounted there, it has worked fine. I do have one of the PVC boards on my Sylvan boat. I screwed and siliconed to the boat.

[-JR-]

What I would do is go into home depo and get a piece of plastic molding and glue that onto your boat. don't have to worry about it realy coming lose and losing your transducer as your transducer is connected to a cable. just buy some good two in one glue or some good PL 5000

[Walleyedude]

Good info - thanks. I feel the same way about holes. If they can be avoided I would prefer that for sure. I'm just not sold on the connection glue will have on Aluminum to PVC as the properties are substantially different and I could see it de-laminating over time.

I'm going on 6 years with mine and no issues. PL is incredible stuff. Clean both surface carefully, scuff them up a little, and glue it on. If you're concerned, then by all means, drill a couple small holes, fill them with marine silicone and then glue and screw the board on in one shot. It should be water tight and it'll give you some added piece of mind.

I don't envision any kind of an epic fail happening though. Inspect it regularly and you'll notice if it's coming loose or delaminating. Worst case scenario, the board comes loose at 50mph and bangs around a bit. If you have the cables run properly and secured, there's really no place for it to go. There's no risk to your prop, and I'm betting you get shut down and get everything in the boat before anything gets broken. There's always the risk of damaging a transducer I guess, but you take that risk of hitting something every time you run across the lake.

The beauty of the Lowrance DI/SI, is that you don't need to have the transducer in the water when running on plane for it to function properly, it's not meant to operate at high speed. That eliminates a lot of stress on the mounting point. That said, it is an option, and I'll likely try it out to start with to see if it's worth running the risk with a $300 transducer.

As for protecting the transducers, I don't see the need in the typical boat setup that you and I are running, the jet boat guys are in a different world lol.

[oilngas]

Both the plastic (no wax etc.) and the Pl are specific for the application. The folks at Calgary Inductrial Plastics were a BIG help.

The PL I used was the "removal of the board from the Aluminum is sort of possible", they also had "you will never get this off" PL product. Both were specific to Aluminum / metal in a below water application.

I glued the plastic directly on the Al transom, just follow the cleaning (basically Acetone) and your good to go. I was skeptical but it works great!!

Screwed the transducer directly to plastic mounting plate. Followed Humminbirds directions re; distances etc. Also a side scan and as i said it's great!

[EZM]

Cool folks - I appreciate the input from you all.

Just screwing around at work surfing the net at lunch - I saw similar thread in another forum.

A guy used a taller piece of marine PVC and glued it down below the waterline and put a couple screws on top above the water line. Picture looked like a shallower boat 20" transom - so it wouldn't be ideal for a deeper vee or bigger boat maybe.

Along with 2 transducers - He also routed out a channel to be used this to run his transducer lines.

Looked like a good plan as yet another alternative for different applications.

[EZM]

I don't envision any kind of an epic fail happening though.

Worst case scenario, the board comes loose at 50mph and bangs around a bit. If you have the cables run properly and secured, there's really no place for it to go. There's no risk to your prop, and I'm betting you get shut down and get everything in the boat before anything gets broken. There's always the risk of damaging a transducer I guess, but you take that risk of hitting something every time you run across the lake.

.

I define EPIC FAIL as - "any and all $#!* that happens to me at the worst #%&** times" .......... lol

I could see that plate coming off as I`m clipping along at 55mph pulling the plastic board through the prop, yanking the cable and pulling my Ethernet port and both head units overboard after smacking me in the beak.

That would be EPIC.