Glue Cleat To Transom?

ctanke

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Aug 28, 2014
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I have a Slickcraft 235 that we're setting up for trolling. Will have a lot of holes underwater when done (assuming we get it right the first time LOL). . .with trim tabs, 2 transducers, and a 4X pickup. Couldn't we just glue a 5" x 36" waterproof cleat on each side of the boat with 3m 550 and then screw in to that? I understand that we'd have to consider this a permanent decision due to the nature of the 550. An added bonus is any future holes for TBD upgrades would just screw into the cleats. For those who have used this product, would I need to use ANY scews to keep it attached it to the boat? Thanks in advance guys, Chris
 

DBreskin

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I'd think you'd want the cleats on the transom, not the side of the boat.
 

GA_Boater

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I'd think you'd want the cleats on the transom, not the side of the boat.

He did say transom, on each side.

There are glue on transom plates and there are screw on plates. We carry these which mount with 2 screws, still better than 3 or more holes for each transom-mounted item. http://www.iboats.com/18-5-Lx8-5-W-...9089802--session_id.411128214--view_id.167614

I personally wouldn't use any plastic type plates, glue on or screw on, for trim tab mounting. If you do, be sure to add some tethers so you can recover the tabs after they get knocked off.

And welcome aboard, ctanke.
 

ctanke

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Aug 28, 2014
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Thanks for the come back guys. To be clear, I would be screwing trim tabs to the glued-on cleats. I understand that 3M 5200 is nasty strong stuff, will rip off the gel-coat coat before breaking free of the bond. Might that work?
 

UncleWillie

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Oct 18, 2011
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While I have never heard of transom plates being referred to as "Cleats", but I know what you mean.

5200 and its cousins will not bond to "Starboard", which is PolyEthylene. It also does not adhere well to PVC or many other plastics.
The 5200 will give a nice watertight seal to the plastic, but you will need screws to hold it structurally.

Trim tabs should be attached directly to, or better yet, through the Transom. They take a beating with every passing wave.

To get a fixture attached with 5200 to release, use a piece of Dental Floss to "Saw" behind the fixture and cut through the adhesive.
 

dingbat

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5200 doesn't have anywhere near the mythical power attributed to it.

The shear strength for 5200 used on Polyethlene is 3.4 kg/cm2 or 48 PSI. To put it into perspective, a weld is rough 60,000 psi
 

Ned L

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in this situation ctanke is using the correct terminology (cleat). I would agree that trim tabs would require more than a glued on cleat to fasten to (they do carry a lot of force). As for everything else I think that would be fine.
 
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I've glued a piece of Starboard (which as I recall is HDPE) to a transom so I could mount a transducer and pitot without drilling holes. In that case I used JB Weld and it worked well (be sure to scuff up each surface with approx 100 grit sandpaper and to scrupulously clean it with a solvent first). I have my doubts about using 5200 for such a purpose, I just can't imagine it being strong enough. I also would have doubts about using this to mount trim tabs, I'd be afraid of the forces involved.
 

ssobol

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Sep 3, 2010
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5200 doesn't have anywhere near the mythical power attributed to it.

The shear strength for 5200 used on Polyethlene is 3.4 kg/cm2 or 48 PSI. To put it into perspective, a weld is rough 60,000 psi


But it is difficult to weld things to fiberglass.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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ok, put it this way, the cyanoacetate glue used to bond the tubs together in todays boats has a strength of 2500 PSI

I still wouldnt glue on trim tabs or transducer

I would, however seal the screws with 5200 and move on
 

Woodonglass

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The Sacrifical Cleats are a good solution for everything EXCEPT the Trim Tabs. They should be permantley mounted to the transom via thru the transom bolts. Here I would recommend coating the holes and hardware with 3M 5200. I'd use 3M 5200 to glue the cleats to the transom as well as predrill and screw the cleats to the transom as well coating the screw holes and screws with the 5200 too! TMHO
 

gddavid

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Jan 4, 2010
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5200 doesn't have anywhere near the mythical power attributed to it.
The shear strength for 5200 used on Polyethlene is 3.4 kg/cm2 or 48 PSI. To put it into perspective, a weld is rough 60,000 psi

It could work. A 10" by 12" sheet on each side, large enough for all of the hardware of each tab to mount into the same cleat and you have enough area to support 5760# of sheer force per tab (ignoring the tensile load of the tabs trying to pull aft). That said assuming you are putting Bennett tabs on, the hydraulic lines run through the upper mount of the cylinder and through the hull so you really need to penetrate the transom anyway.

Instead of the 5200 cleat approach I would grind off the gelcoat and just build up the laminate with polester resin and matt until you have enough thickness for all of your mounting hardware to bottom out before penetrating the core material then lay new gelcoat over that. Slickcraft's were laid up pretty thick to begin with and you probably wouldn't have to add too much. For the upper mount of the trim tab you will need to oversize the hole for the hydraulic line and then fill it in with thickened resin an then drill through this for your final passage, this is the tried and true methode for preserving the transom core material. Finally, you usually get away with epoxying the transducer to the inside of the hull and letting it read through the fiberglass if the hull isn't fully cored. This will eliminate some holes.
 
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theBrownskull

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Jun 23, 2012
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Have you thought about trying 3M waterproof tape like the type used on the Keelguard brand bow scuffbuster. That stuff holds well and does not peel the paint. It may look "tacky" but you could also have a lanyard attached so if it falls off it won't be lost?
 
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ctanke

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Aug 28, 2014
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A few more questions . . . and thoughts. . . .
1. This is a pretty rare Slicker in that the hull is yellow. Trying to match the color after building up with resin could prove difficult (?).
2. There are two sets of old transducers on the boat now. Would it make sense to fill these holes and then glue/screw some sort of cleat over them? This would serve to cover up the holes and allow us a fresh start at mounting updated equipment. Or should we just fill these holes and then redrill in the fill material for our mounts? Not sure why, but the "cleat over" idea seems to make better sense to me. Please talk me back from the cliff is this is foolish.
3. Back to the 5" x 36" x 3/4" cleat idea once again. If its caulked/glued and secured with screws that do penetrate all the way through the transom would this not make a significant substructure to screw the trim tabs to? Is it really necessary to attach tabs with thru hull fittings? That's just more holes through my boat! Thanks in advace for your counsel, Chris
 

ctanke

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Aug 28, 2014
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A few more questions . . . and thoughts.
1. This is a pretty rare Slicker in that the hull is yellow. Trying to match the color after building up with resin could prove difficult (?).
2. There are two sets of old transducers on the boat now. Would it make sense to fill these holes a then glue/screw some sort of cleat over them? This would serve to cover up the holes and allow us a fresh start at mounting updated equipement. Or should we fill these holes and then redrill in the fill material for our mounts? Not sure why, but the "cleat over" idea seems to make better sense to me. Please talk me back from the cliff is this is foolish.
3. Back to the 5" x
 
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Ctanke,

I responded to your trim tab post for this boat. I too have the same boat (mine is yellow also with the factory hardtop). Remove all the crap off your transom. Install the trim tabs per Bennet instructions with the Bennet hardware. There will be a stainless steel backing plate/spacer for the tab mount flange. Use the 5200 to seal everything well including the backing plate and the screw holes. Use quick set 5200 because the normal stuff tends to run. For the transducer and other stuff use the same method. Lots of 5200 to seal everything well. Any left over empty holes below the water line should be cleaned and then fill with a stainless screw with 5200. Go boating.
 

ctanke

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Aug 28, 2014
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Hey Greg,
Did you use through hull fittings to attach your trim tabs to your Slicker?
 
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