Hull Fairing Set-Up

[FYC7.9]

I am looking to fair the bottom of our 7.9. The previous owner used Interprotect, but did not fair it after the final coating so the surface is a bit rough. The boat is currently on a trailer and am looking for ideas on what people have done to set it up to be able to access the areas under the trailer bunks. Thought about jackstands, but am concerned about the entire boat weight being placed upon them (instead of the keel as is the intention with them).

Any thoughts/ideas?

[Tim Bosma]

When we were re-doing Blackbeard, we slung it from the rafters of a warehouse using 3 ton tow straps and 3 ton chain lifts.

[FYC7.9]

I have heard of that being done before. Seems like a good route to go, but I might have trouble finding a warehouse that will let me do that. Anyone have any thoughts about using jack stands temporarily?

[LarryE-old]

I have 2 short jack stands. I have sectioned my bunks where there are now 4 instead of 2 real long ones. I jack the boat up in sections, with a bottle jack, use a 2x4 between the jack and the boat, to spread out the load. Then I install the jack stands and let the jack down. Remove one section at a time. Sand, paint and reinstall bunk and go to the next section.
I have a hard surface that the boat sits on and a auto creeper to lay on and roll around under the boat.
Has worked good for many years and am getting ready to take the boat out, in a couple of weeks to paint again. Water getting cold and it hate cold.

[FYC7.9]

Thanks for the idea. This could be the easiest way to get done what we want to do with out involving the travel lift and what not. We can probably get the hull long-boarded in a couple (long) days...

[FYC7.9]

Has anyone ever set the boat on its side or flipped the boat over to work on the bottom?

[dave]

One must remember that most all keel boats have the keel bolted to the bottom or to a short extension, and that all of the ballast is below that point. Also, many boats don't have balsa cored hulls, which are stiff as the dickens!!!! Most of the ballast in the daggerboard version of the 7.9 is in the hull, and blocking the board will only cause it to rise and possibly jam as the boat is lowered, while taking hardly any weight off of the pads. I've worked on many 7.9's that sat on 4 pads for weeks or months with absolutely no hull deflection/deformation.

Another point. I did this type oi work from 1975 until I had shoulder surgery in December of 2010, with many 100's of hours spent pushing a fairing board sander back and forth, and don't want any more of it!!!! My shoulder dock told me flat out that my days of working over my head should end, but that if I HAD to do it, to make sure that I keep my elbows in. This takes some told off of the supraspinatus muscle and may save you some shoulder surgery!!!!

http://www.healthhype.com/supraspinatus ... -tear.html

[FYC7.9]

What I was thinking was to lift the boat up using a travellift and using old mattresses to set it on to prevent anything from getting dinged/scratched up, Then flipping it over to the other side. I have see this done with j24's and J22's with no real problems. Have the boat on its side would make the job of longboarding MUCH less painful then having to push up from underneath the boat. Having done that in the past i know how miserable it can be. Anyone see any issues with this since the boat has centerboard?

[dave]

JMHO here................... I'd remove the board first. It and the mast step are the two iffy design and build areas of the boat, including the trunk. The hull and deck are close to bullet proof if you keep the water out, but I would never even think about putting much lateral load on the board trunk with the board raised even though many have wiped out under chute with the board somewhere besides all the way down, and having it removed completely should make for an easier roll, if such a thing exists! Good luck with it, and save those shoulders!!!!

[Tim Bosma]

I'm with dave. Pull the board out. that way you can set the board on some horses and fair it as well.

[dave]

I'm with dave. Pull the board out. that way you can set the board on some horses and fair it as well.

Right, but even more importantly, this gives one a chance to do a REALLY GOOD assessment of the board! Mine had skins that were peeling away in the water, opening up like jet intakes on the leading edge. After pulling the board and laying on its side as Tim suggests, I tapped everywhere and cut away any skin that had separated from the core.................... which was an easy 30%!!! With time and drying out, almost ALL of the skin warped away/peeled off the board! What I have now is just the core with no glass skin, and that has cracked in half from not always being supported properly, as all of the weight is in the bottom.

No big deal really, just par for the course when I ever get around to putting it all back together. The board was so asymmetrical from the factory that to get it even close to true would have meant grinding completely through one skin and then past that enough to lay new laminate on before refairing to specs, and then some!!!

Not trying to scare anyone here. As always, nothing but the "unvarnished" truth, and as always, all boats have their problem spots........................

[Tom Elsen]

I've put a few 7.9s on jack stands before with no issues. Tie the jacks together well before having them 'take the load'.

If you're concerned about point-loading weight, find some scraps of very dense foam or 1.5" styrofoam to use.
For long-boarding, I'd use five jacks. Three primaries - two under the aft bulkhead and one on center about three feet forward of the board box. Two 'safeties', outboard and slightly forward of the center jack. And watch for weather!

An easy somewhat safer alternative is to stack some cribs out of 6"x6" dunnage pieces. Sometimes you can borrow these (for a 12 pack or so) from a heavy equipment outfit or a boat yard. Use a bottle jack fore/aft to raise the hull, and the same foam technique from above to ease the point-loading.

Under NO circumstances use old phone books to bear ANY of this load anywhere at all. That is unless you enjoy dodging very heavy objects.

[FYC7.9]

Thanks for the reply's! I am planning on taking to board out completely at some point to fair it properly. This is the second 7.9 I've worked on...the first one had some delamination issues similar, but not as severe, as were mentioned before. I wold like to avoid as much as possible fair the bottom by sanding underneath the boat. Its hard hard work as it is without having to try to do the job while pushing up instead of down onto the boat. I know of people that have flipped an 7.9 before, but that is beyond my capabilities at the moment. Ideally I would like to get it on its side to do the work, the flip it and do the same to the other side...a safe way to do this is the problem. Worst comes to worse I can do it the old way, underneath, with jackstands.