Preparing for new bottom

[Superduty88]

Hey guys I just took my boat apart yesterday to redo the bottom I'm going with steel flex 2000 but was wondering what type of grinder/sander you all use to take the old stuff off its my first time doing it.. I used the search bar but didnt really find anything to help me out its a 10ft by 7ft aluminum deck over I'm not sure really what I have on it now but it's a gray color... Thanks for the help

 

[jimmyflfr]

I went to Home Depot and got a 36 grit soft sanding wheel on my big grinder and I lightly sanded the whole bottom. This grit will scratch it good so the epoxy will bond. You might not need as much as 36 grit but it worked great for me. The guy at fasco swears by cleaning it w only acetone before application

 

[Superduty88]

Thanks for the reply I was kinda on the right track I guess I'm heading to Home Depot on my way home from work and gonna give it a shot if the dam rain will let off!!!

 

[Superduty88]

If it is a riveted boat be very careful not grind the heads off. If you grind the heads off the boat will leak and the bottom will come apart. X2 on the sanding and then cleaning with acetone. When you sand you really just need to ruff it up. You don't need to take it all the way to the aluminum.

10-4 thanks for the info I believe the boat had Polly on it before and they patch all the holes and went with the slick bottom the hull never leaked a drop of water but I'm kinda worried on grinding it down cause from the looks they used some kind of silicon or something of that nature I just don't want to start a problem I don't have I no I'm not gonna grind down to bare aluminum but shouldn't all the old bottom come off or can I ruff up what I have and put the new bottom over that? Sorry if these are dumb ?s I just never delt with slick bottom I have done Polly but I'm trying to keep it light as possible I don't run ruff ground at all

 

[Seven3]

When I re-did my boat early this year I was advised to use a 24 grit disc. It gives more bite for the Steelflex to hold on to. I brought the bottom down to bare with the 24 grit, then applied a one gallon layer of Steelflex 9X, then I applied a one gallon layer of Steelflex 2000 on top of that. I recommend applying a one gallon base layer of 9X first, as it doubles the thickness of your bottom, plus the 9X won't add much cost to the project (I'm pretty sure a gallon of 9X was under $50). As advised by the guy at Fasco, as long as you apply the 2000 on top of the 9X within 8-12 hours, you can apply it directly without scuffing first. I used the techniques advised by Mike Thurman and John Fenner, and it is holding up very well as the boat has about 20 hours of run time on it with no chips in the bottom.

 

[Seven3]

This is a post John Fenner wrote on my boat's Build Thread:

You will only need one gallon of Steelflex to coat the bottom, grind the bottom with 24 grit discs on a 7" sander, run the scratch marks side to side. Use a good plastic mixing pail 1.5 or 2 gallon, get a paint auger in a drill to mix both parts thoroughly, pour an even 6" wide stripe up the center of the hull, make sure there is no unmixed product on the rim and set pail upside down on the hull. Using a epoxy rated short nap "red"roller cover on an extension pole, start from the rear working the paint side to side, working forward once you get to the front start working it at an angle from back to front from both sides, then roll it out fore and aft when it is all laid down evenly. Roll the sides to your tape line, then the transom lip. Then finally start from center of hull and roll full continuous from back to front, overlapping paths by an inch till both sides are laid smooth, roll the chine all the way as well. Check periodically for runs down the side, touch up with roller.
If done while in direct sunlight you will need to hustle as it will start to kick off in about 15 minutes.

This is a post Mike Thurman wrote on my boat's Build Thread:

If you just toll the steelflex out it with have a lot of ripples or orange peel look to it. To make it smooth and right you will need to also get a plastic squeege spreader. And at that right time(About 10 minutes after it is rolled out) you need to drag that squeege from front to rear to smooth out all the roller ripples. I thought you we're putting Gator Glide on it?? That steelflex 2000 will not last very long. The silicones in it will not let it stuck to the aluminum very good. And if you plan on steelflexing the sides then the paint will not stick to it. On my hull I steelflexed the bottom and sides.with regular steelflex 9x white then used my DA to sand the bottom with 100 grit and then put steelflex 2000 on top of the 9x. It has the durability of 9x, the paint adjusts to the 9x better than anything and then I have the slickness of 2000. I have steelflexed more aluminum hulls than anybody on here and can tell you what will and what will not work. And just 2000 on the hull will not last. It is top greasy to stick to the aluminum and wears quicker than the 9x.

 

[Superduty88]

SEVEN3 thanks buddy I think you pretty much summed it up for me I appreciate the help guys gonna try an tackle it tonight and Cary on with it threw the weekend thanks y'all...slide safe!! :salute:

 

[Seven3]

Fasco told me to lay down a thin 'tack-coat' layer first, let it get tacky, then apply the rest of the gallon. I believe I waited around an hour or so between laying down the first tack-coat and the rest of the gallon. Then, of course, you have to repeat the tack-coat process again for the second gallon of Steelflex 2000 if you use the 9X first. If you do the tack-coat method, don't mix the entire gallon together all at once...it will turn into a hot brick while you wait for the first coat to get tacky (learned that the hard way). And don't forget to remove your tape lines while the paint is still tacky. If you wait till it dries, the tape will be there permanently. It's a lot of work to do it the way I have described, but like I said my bottom is holding up great, so the results are worth the time.

 

[Superduty88]

10/4 thanks

 

[mscott]

I put the gator glide on mine. There's a gallon of base then a gallon of the slick. Sounds like what you're getting done with the X9 and Steelflex. I sanded mine with 24 grit and started applying the base layers and waiting for the dry time. Then after the Cure time on the base, 3 days, I roughed with scotchbrite pad and put the slick to it, just as the manufacture stated. Worked like a charm and slick as snot. Rolls through 2 inches of water full of weeds and small willows at almost idle. Rolls off stumps at slow speeds. Left about 1/8 to 1/16 inch thickness on bottom. No scratching or wearing yet.