Smart Tab SX install went WRONG!!!

[hemi2nv]

So I got the trim tabs in today so I started to install them when I got home from work. Well I lined the first hinge up with the bottom of the transom and marked the holes. I drilled the holes and removed the tape and everything looked great with no cracks. I started all the screws and then began to tighten each one down by hand with a screw driver. At this point I started to hear some cracking but nothing to bad until I got to the bottom middle screw when I heard a big cracking sound. After geting them all tight I started to inspect the work and noticed a large crack on the bottom edge of the transom around the middle screw. I only had my Iphone with me so the picture quality sucks at best and then it started to rain so I had to call it a night before I could inspect the area from inside. So what do you think I should do? HELP!!!

 

[hemi2nv]

I did not counter sink the holes. I followed the directions to a T and asked on these forums the other day for any tips before installing. The only thing most said was to start in reverse which I did. The drilling went great and the holes were perfect But it appears that being that close to the bottom edge the stress was to much. Do you think I should remove the bracket and inspect the crack or if it did not go all the way thru to the inside leave it be? The directions included said nothing about counter sinking the holes and the crack happened with the screw only half way in. I did apply some marine sealant to the crack.

 

[hemi2nv]

So to counter sink the holes would you just get a bit 2/32 larger and drill deep enough to get thru the gelcoat? Do you think I'll have any problem re-tightening the screws after removing them? I can live with the crack as long as there is no further water damage. If water was to get under the gelcoat in this area will it cause damage like it would on a wood transom boat? Thanks for your help!

 

[Frozen]

i don't see how a non-counter sunk screw would benefit from a counter sunk hole. If I under stand this correctly, its a flat head screw that holds down the hinge. So the hinge is flat against the gelcoat. And that a counter sunk hole would be no benefit, or maybe I'm just missing something.

 

[hemi2nv]

The counter sink would prevent the screw from contacting the gelcoat when screwing it in. I just did not think it would do this kind of damage. All the other holes are fine and look good.

 

[hemi2nv]

Sfergson - Thanks for the tip on the counter sink, I pulled the hinge off and the celgoat was cracked on all the screws and two of them were bad. I patched up the two bad ones and counter sunk all the holes. Then I used a healty dose of marine sealant and reinserted the screws. I then moved on to the remaining holes and counter sunk all the screw holes and did not hear any cracking when inserting them. I can't believe the damn instructions did not say anything about counter sinking the screw holes to get the gelcoat away from the screws!!! Anyway here are a few pictures of the carnage and the final install. NOTE: Anyone that installs these SHOULD counter sink the holes with a bit atleast 1/16 bigger than the hole it'sself!!!

 

[Dave S]

Even though it is too late now, a simple way to countersink holes is to use a Phillips bit on your electric drill. It does a great job of creating a tapered hole in the gel coat and is what I normally use when putting small screws in gelcoat.

Dave

 

[hemi2nv]

Thats a good idea as well, I just wish someone would have mentioned the counter sink issue when I asked for install tips on Monday!!! Oh well you live and learn and atleast they are on, now I just need the weather to clear so we can head to the lake! I'm going to email Nauticus and suggest they update the install instructions to include counter sinking the holes, matbe I can save someone else the frustrations I had.

 

[r8nger]

Don't feel bad Searay doesn't even counter sink holes. If you remove some of the speakers and stuff, it looks like they cut it out with a chainsaw. The idea behind counter sinking, is that, it removes the sharp edge where stress cracks start.I have a large crack in my gelcoat from the hack job they did when they installed the anchor locker drains. On larger holes and openings, take a file and just knock the edge off.That will keep any cracks from starting.it's never too late to do. If you have something apart, take the time to do that. You can get a coutersink bit from Hone depot for $8. A bigger drill won't leave it nice and smooth, like the right bit will, plus it looks proffesional when you are done.I would get a gelcoat repair kit and touch that up before reassembling it, and you should be fine.Experience is expensive and unfortunately we are not born with it.Learn as you go. Now you'll learn how to make a minor gel coat repair. ( trying to be optimistic) Good luck

 

[fwebster]

There is one minor addition to make here: The reason behind countersinking isn't to remove a sharp edge on the pilot hole, but rather to remove some (about the upper 1/2) of the gelcoat. Removing the gelcoat eliminates the chance for cracking. Just be careful not to remove so much that you drill into the fiberglass beneath.

Also, it is risky to use a drill bit for countersinking because the drill bit has only 2 flutes and tends to grab. If it grabs, you can easily drill the hole deeper than needed which weakens your attachment. A countersink bit like this is a better choice:

http://bistools.com/product_info.ph...d=598&osCsid=26171ebbe8ec3e9703abe558bef63f9a

Note: I'm not recommending this company or this particular bit; it was just the first photo of the right bit design I found.

 

[Lazy Daze]

Hemi, Don't overlook the search feature on this site. Hindsight is 20/20, but there are at least a few threads with excellent instructions on how to properly drill into gel/glass. Oh well, glad you got it figured out now.

I also prefer using an actual countersink bit, similar to what Frank linked to. But, in lieu of that, grab a bit that has a slightly larger diameter than the screw threads and use it to create the countersink. But, here's the key: Do it by HAND. Otherwise, like Frank said, it's too easy for that bit to bite down and pull itself in faster than you can pull the drill away and you'll be left with a big hole.

Good luck in your next project! :smt001

 

[wish2fish]

love the outdrive cover!

 

[hemi2nv]

That high dollar stuff there! Lol... I had the boat out front and did not want to advertise the SS prop. Lol...