3M 5200 or 4200 on trim tabs?

[Troy JK]

I Stopped off at a boat dealership to pick up some 5200 for my tab install. The counter guy asked what I was using it for so I told him. He said he didn’t think it was a good idea. About that time a mechanic walked up and he asked his opinion. The mechanic said “ you can use it for that but I wouldn’t, if you ever bend one and have to replace it, there’s a good chance you’ll take some gelcoat off with it, the 4200 would be better. I thought about it for a second and went with the 4200. My thinking is that with our application, the actuators are pushing the tabs against the hull and not away from it so the extra bond strength isn’t needed.
I also did a quick net search on it and found one post from a guy that said he had removed an outboard that had 5200 just around the bolt holes. he lifted the boat off of the trailer trying to get the motor off after the bolts were out. When it did come off it took some gelcoat with it.
I’m not going to say you can’t get them off with a little heat and the right razor blades, but in our application I don’t think it’s worth the risk.

This may have been debated but the closest I found was in 2014.

 

[Luc Lafreniere]

In general, if you plan on ever having to remove something, use 4200. Only use 5200 if you want it to actually be permanent. I live by that rule.

 

[zipper]

If I recall, the install instructions call for 5200. I did use 5200 knowing it is permanent. You can't go wrong using 4200. Use fast cure if you can find it. I did not plan to ever take them off. The tabs are pretty tough. If I had to replace one, I might pull the hinge pin and try to swapout the damaged Tab. It is still a PITA but you can use this to break the bond of 5200. Marine Formula™ - 12 oz. Aerosol

 

[Troy JK]

If I recall, the install instructions call foe 5200. I did use 5200 knowing it is permanent. You can"t go wrong using 4200. Use fast cure if you can find it. I did not plan to ever take them off. The tabs are pretty tough. If I had to replace one, I might pull the hinge pin and try to swapout the damaged Tab. It is still a PITA but you can use this to break the bond of 5200. Marine Formula™ - 12 oz. Aerosol

I don’t have mine yet but I was wondering if you could get the pin out, then back in and know it would stay there.

 

[Canuckjetboater]

I Stopped off at a boat dealership to pick up some 5200 for my tab install. The counter guy asked what I was using it for so I told him. He said he didn’t think it was a good idea.

@Troy JK ..... I agree with the counter guy. Have helped a lot of friends install trim tabs and had them on four boats. Always used 4200 or Sikaflex. 5200 will never come off and pull chunks of your gel coat out right down to the fiberglass. The 4200 will work great.

 

[Beachbummer]

I was happy with the additional strength I thought was provided by 5200. Where it is exposed it still seems mildly flexible. I expect if I ever needed to remove the tabs perhaps it will be quite some work to remove, but it won't be harder than removing all the glue from the hydroturf. Time will tell. I expect the tabs to last the life of the boat, and if any replacements are needed I expect the actuators to be the ones needing replacement. I went with the 5200 as directed. If you are comfortable with the 4200, it's your boat, the tab police won't come to take them away if you use 4200. I agree if you think removal is priority over max strength 4200 is the right choice.

 

[Canuckjetboater]

It also depends on how long you plan to keep the boat and if it will be used in salt water. I agree with a post that says swap the movable tab plates and leave the to hull attachments in place - that's a good idea. I recommended 4200 because I have had friends who had screws rust and have to be replaced. With 4200 the job isn't easy but it's not hard. With 5200 it's a lot harder. Also, if the tab design changes you might not be able to swap the movable tabs out.

 

[captainhook]

I spent a solid day helping my father in law remove his tabs on his Luhrs this past weekend and we were very glad that 4200 was used. His are bolted into the bottom of the hull in a recessed area and one of them was so stuck that we bent it a fair bit prying it off. His weren’t broken, but he wanted to replace them with switches that have LED position indicator gauges. This required removing the actuators and replacing the top half (called “hinges” for whatever reason even though they actually aren’t hinges) with the versions that have sensors and electronics.

Point is you’ll never know when or why you want to remove them and I think 4200 is plenty for this job.

 

[zipper]

I don’t have mine yet but I was wondering if you could get the pin out, then back in and know it would stay there.

I have not tried it, but as long as they are built the same you could drill out the slightly flattened end of the knuckle that holds the pin captive, drive the pin out, reinstall new section and then again flatten the knuckle to hold the pin. It sounds good on paper, but don't know how it would actually work on the boat.