Hull fairing recommendations?

[irwinsailor]

I think Jamestown dist. sells sand paper in rolls and some is attached with hook and loop or you glue it on.

[RBEmerson]

Er, glue makes the boards pretty much one-shot affairs and hook and loop, at least on the bottom, would make things somewhat ...ah... unfair? I suppose a strip of hook and loop on the top of the board, at each end, might play somewhat. Although... hmmmm... come to think of it, a couple of countersunk flathead machine screws, through the board from the sandpaper side, and a strip drilled to slide over the screws (maybe carpet tack board???) snugged down with wing nuts might do the job. Hmmmm...

[David M]

I faired the entire bottom of my aluminum boat. I had it sandblasted down to bare aluminum. It was about as fair as a potato. I rolled on six coats of Interlux 2000 to create a barrier coat. I then started fairing it with Proline "green hand" which is a green colored two part sandable epoxy fairing compound. It took me two weeks to do this. I made fairing boards out of 5 inch X whatever aluminum strips that I bent by hand....stepping on them more like. Some of the aluminum strips were as long as 48 inches. I had different radiuses and different length fairing boards. I sanded with a Makita 7 inch circular sander/polisher using 36 grit stick on disks. I had some pretty serious deltoids after a couple weeks. It was hard as hell and I would not want have to do it again.

If you can get an air powered fairing board then go for it. I did not have that luxury at the time.

[Celestialsailor]

Originally Posted by RBEmerson

I like the idea of using T1-11 strips and, in fact, have a bunch of it handy. Where does the sandpaper come from (kinda think West is a tad short on 48 x 4 in. paper of any grit) and how's it attached?

I used sanding belts and cut them. Then rolled the ends of the belt over the ends of the T-111. I used short 2x2 blocks as handles and clamps for the paper. When I said 4"X48", that is from memory. It may have been shorter. It was easier to use with 2 people. Good luck

[Sam Plan B]

I have used - believe it or not - talcum powder as fairing compound. It's mixed into catalized epoxy resin until it has the consistency of stiff cake frosting. Apply with a wide putty knife. The best thing is, it's very inexpensive at $1 a pound. It's soft and sands easily even by hand. And it doesn't make you itch.

[Kanani]

Originally Posted by RBEmerson

I like the idea of using T1-11 strips and, in fact, have a bunch of it handy. Where does the sandpaper come from (kinda think West is a tad short on 48 x 4 in. paper of any grit) and how's it attached?

3M Wet n Dry Sand Paper Roll 4" X 50 Yards 80 X Grit - eBay (item 140288571491 end time Jan-10-09 16:31:37 PST)

However, IMHO, you may tire pretty quickly trying to use 4" wide paper. Most people use 2 3/4" and just criss-cross your strokes.
http://shop.ebay.com/items/_W0QQ_nkw...romZR40QQ_mdoZ

[44'cruisingcat]

Originally Posted by RBEmerson

Er, glue makes the boards pretty much one-shot affairs and hook and loop, at least on the bottom, would make things somewhat ...ah... unfair? I suppose a strip of hook and loop on the top of the board, at each end, might play somewhat. Although... hmmmm... come to think of it, a couple of countersunk flathead machine screws, through the board from the sandpaper side, and a strip drilled to slide over the screws (maybe carpet tack board???) snugged down with wing nuts might do the job. Hmmmm...

You buy the "hook" side in a roll, and completely cover the bottom of the board with it. The "loop" is on the back of the sandpaper. Securing the paper at the ends is ok over short lengths, maybe up to 3 feet, but much longer than that and the paper will move around on the board, instead of moving over your hull and sanding it.

It's important that it be easy to change the paper. If it's a hassle you'll tend to keep going with worn out paper and make a hard job even harder.

[bob kingsland]

I long boarded my whole 50' hull, using 36 grit up to 220. I made long boards, both one and two man boards, of 3/8" ply up to 6' long, with 2 nicely shaped handles on either end for the 2 man boards. Glued the sand paper on with spray glue... just peel the paper off when dull, shoot some more glue at it, stick a new piece on. 2 guys with 36 grit, working with the board diagonal, wrapped around the shape, can take a lot of epoxy/micro balloons off in a hurry.
Found a local manufacturer of belts, who had 6' wide rolls of every grit, 100's of feet long, and a machine with adjustable rolling cutters on it... he could make any length, any width you wanted, and it was only a 2 man shop. The 4" is a lot of work, but also makes the whole job go faster. I also made a few shorter, 1 man boards of 1/4" for more flexible areas. A very true, fair, unkinked batten is an essential part of the process, as are different colors in the base coats so you know when you're getting close to the substrate. High build primer is good in the final stages. Basically you put a lot on and take what seems like 90% of it off.
Hope this helps. More on the web site.
Best, Bob S/V Restless

[Cadence]

If I understand you correctly, I believe I'd use an epoxy filler. You may want to consider a thin mat and SIystem Three / West System. I say System Three because it was cheaper. If the hull is sanded to the point of having some tooth.

[RBEmerson]

In the course of scraping and sanding on boats, I've figured out three things: 1) [buffing | sanding] machines can get you into trouble faster than you can say "oops!"; 2) sandpaper is an expendable item, if you're not using fresh paper after 5 minutes, you're wasting time and effort; 3) narrow, sharp scrapers work better and faster than wide scrapers. Related to 2), cheap sand paper may save money but costs time. It's easier to find extra money than extra time.

[Oceansandmts]

The last hull we faired (me: older, experienced. #1 son: young, athletic oarsman. Guess who did the bull work?) we applied the epoxy home-brew fairing compound with a notched trowel, leaving narrow ridges of fairing compound on the entire section to be faired. Long-boarding goes more than twice as fast when you are only sanding narrow ridges of filler. After long-boarding down to a fair surface, we used a regular spreader to fill the spaces between the ridges. Then a quick once over with finer grit paper on the long-board and the job is done!

If you use this method, be sure your fairing compound is low-shrink, or you can get a little patterning when the second application of filler shrinks in between the ridges of the first application. Below the waterline this would not be a problem.

The other possibilities include renting one of the big, air-powered rotary fairing machines, or having a party with lots of beer and young, fit friends with long-boards.

[indypopeye]

careful!!!
545 epoxy primer from awlgrip is an extremly hard barrier coat.
Great for spraying after you have finished the faring job.
High build primers will do you a great job, and are easier to sand.
And since they are epoxy primers you can spray on multiple coats for real high build in the ruff areas.
Acetone is a great way to dry moisture. wipe down pocks and holes with liberal amounts of this stuff.

indypopeye
trimaran Lady Triana
Beaufort