Core Sound 15 -- The Decision and Some General Questions

[Ken_Potts]

How do I find reply #72?

[PeterP]

Ken you have been working too hard. Time to sniff some salt air. But before you go read your post and notice the reply no. Work back from there. PS -instead of thanks promise not to bring up tore up bailers anymore PeterP

[Ken_Potts]

  I thought I was missing something incredibly obvious and once again I'm right  ;D

  I'll do my best to keep that promise, but if I have a mishap at the boat ramp I'm probably going to say something...

[Greg Luckett]

I've decided to not permanently glue the rub rails in place, but want to make them "sacrificial" and so replaceable. I'm wondering what folks use for a sealant. The plans say "silicone" or "mastic", but mastic is so generic a term that I cannot figure out what the devil it is because there are so many kinds! A little help here would be greatly appreciated. Thanks. ~Dennis

I would use the Dow 4200 stuff....not the 5200.  It works well for sealing screws, etc., yet does not set up like the 5200.

[Guest Dennis M]

I got the boat painted yesterday -- "Shaw Blue" from system three. I can tell you that 90 deg heat and a poorly lit garage do not make for the best results!

It is clear to me that after painting the boat I do not understand "fairing." All the tape edges were feathered and faired, all epoxy drips were sanded off and when I ran my hand over the everything it felt as smooth as the proverbial baby's behind. But...but it does not look smooth. Standing back, it seems as if all those things "printed" through the paint, but when I go to run my hand over the surface -- smooth! I don't get it. Also, there were a lot more divots sanded into the ply than I thought. I did not find them before painting, but I can see them now! Now that the boat is painted, I am not going to go back and "fix" it. I'll do that down the road when I decide to repaint. I would like to know if anyone can point me to a thread or book that will discuss such things so that I can be prepared in the future. I'd appreciate that.

Also, I made a mistake that some folks might be able to learn from in future. System 3 notes that one can put the paint on bare wood and epoxy. But after putting the primer on, I did some filling and fairing of things I did not see before, but did not go back to prime those areas. Too bad, because the texture/pattern of the paint is noticeably different from those primed and unprimed areas. Good thing this occurs mostly on the bottom of the boat. The fish won't be able to tell the difference. And once I run over a few boulders in the UP, it will all look more uniform! ;D

Nevertheless, the half oval on the skeg goes on next and then back over she goes for the finish of the interior. It won't be long now, or so I hope.

I take it that the bailer is not put on until the interior of the boat is painted. Is that correct? ~Dennis

[Greg Luckett]

Dennis, I feel your pain. On my Spindrift's hull, I sanded, faired, sanded, faired, etc., several interations and it both looked smooth and felt smooth.  Then I primed and found many flaws, which I filled, faired, sanded, primed, found more, did it again, and again until it looked right.  The last step was a final primer coat.  It remains to be seen how the finish coats will turn out. :-\

[Guest Dennis M]

Greg, I hope you get better results than I did and it sounds like you will. I probably would have seen the problematic areas better had I had better light in the garage. Maybe your boat shed set up is the way to go for future projects -- especially when it comes to finishing.

[Charlie Jones]

:D

I ALWAYS consider the first coat of paint- both primer and top coat, to be sacrificial. It ALWAYS shows up areas that need more fairing. FAct of life. Don't be hard on yourself- that's just how it goes.

[Guest LeeH]

We have used some black epoxy primer over boat bottoms where we've gone in to repair blisters (fiberglass boats). The black epoxy dries to a brilliant glossy shine, and it's astounding the "flaws" it will highlight. So, as Charlie says, it's definitely sacrificial - more to show you where you're at with the fairing than anything else. At least the first coat. At some point you just have to say, "good enough".

[John Burritt]

Dennis - How are you sanding the surface?  (Sorry, I didn't go back up the thread and look)  Palm sanders and random orbitals will make smooth, but not fair.  You just found out the difference.  When I'm lazy, I'll use a half-sheet sander - nothing smaller.  If I'm serious, its some kind of a long board, just flexible enough to bend to the curve of the hull.  Again restating the obvious, sand away the high areas - don't sand the hollows.  You've also learned that if you sand through the primer - re-prime!  You might be able to paint over bare wood in some spots, but it'll show, usually even after several coats.  It's so tempting to go on to the finish coat that I have to relearn this the hard way every so often.  You didn't do anything the rest of us haven't done at least once.  As to your lighting problem, you might try some portable flood lights when you're painting.  Its embarrassing when the well lit side of the boat looks better than the other.  Don't ask how I know.

[Greg Luckett]

Greg, I hope you get better results than I did and it sounds like you will. I probably would have seen the problematic areas better had I had better light in the garage. Maybe your boat shed set up is the way to go for future projects -- especially when it comes to finishing.

The light in the tent is excellent, but only during the day.  I learned the hard way to only paint during the day and only in the warm months here...about 4 or 5 month window of opportunity.  From previous builds I have learned to spend as much time as it takes to make the boat look good prior to the finish top coats, or it is a lost cause to ever look good by me.  Light is the key for me to paint and there is a history over the years of me missing lots of flaws trying to do spackle, painting, or sanding in poor light.  I guess I am just a slow learner? ;D

[Bikermouse]

This is probably a dumb question, but just how long is a sanding longboard?  I was looking at sandpaper at the store last night, and the longest I could find was a 31" belt for a belt sander.  Cut it at the seam and tack to a piece of 1x ?

[Greg Luckett]

This is probably a dumb question, but just how long is a sanding longboard?  I was looking at sandpaper at the store last night, and the longest I could find was a 31" belt for a belt sander.  Cut it at the seam and tack to a piece of 1x ?

I have seen them from about 1 to 2 feet.  The length will depend on the arms and reach of the person using it.  Additionaly, sanding paper can be bought in rolls of various widths and many feet long.

[Ken_Potts]

The sanding area doesn't need to be that long.  I use a half-sheet of sandpaper cut lengthwise 4.25" x 11"(?)

I stick it to a strip of 1/4 ply that is not quite twice the length of the paper (4.25" x 16"-20").  The ends of the plywood have pieces of wood glued to them for grips.  The plywood needs to be flexible (thin) enough to bend around the curves of the hull.

[John Burritt]

You can get both rigid and flexible sanding boards 2 3/4 inches wide and about 17 inches long with a light foam pad to cushion the paper.  They have clips on the ends for attaching the paper - or use sticky-back paper.  I have seen 3 ft boards 4 1/2 inches wide, but haven't used one.  Rolls of sticky-back paper in a variety of grits are available from several sources.  Woodenboat magazine #208 has an article on building custom sanding boards.

[Guest Dennis M]

Lee, I'm done! Seriously, when the time comes to repaint the boat, I'll fix things then. Do not do today what can be put off until . . .!!!! ;D

John, yes, I smoothed things out with a ROS and palm sander. I filled the dings, nicks and gouges that I could see and smoothed them out. I've learned my lesson here. I do have some questions about using the long board -- sand the high spots, you say, but what about areas on the CS like the panels that have been double taped and therefor present an inescapable high spot on the hull. How do you avoid sanding through the tapes and the like, or is it just so obvious the question is not worth asking?

Charlie, I should have hired you as my boat building "life coach" before I started this project. You could have made some money by simply saying, "Fact of life, move on and get over it" every time I pointed at the hull and said, What the devil??  ;D

[Charlie Jones]

OK- couple of points- those taped areas can be filled with a squeegee and thickened epoxy to fair them. Just knock off the really rough parts-I use a flap sander in an angle grinder.

I NEVER touch the boat with any sanding paper of any form, except for the obvious of smoothing scarfs, and fairing the taped edges, until the first coat of resin is on the glass.THEN I only lightly sand ( and often just use a scraper) JUST to get rid of any nibs, stuck on bugs, etc. I roll on two coats of thickened epoxy to fill the weave. THEN and only then do I begin sanding. Okume plywood is amazingly fair- if you LEAVE IT ALONE, you won't have any dished out places.

My long boards are sized for 3 x 21 sanding belts.I cut them apart spray the board with spray adhesive and stick the belt on . I have two- one is 4 MM okume and the other is 6 MM okume

Dennis- I would'a done it too;) Can ALWAYS use some extra income. I recall talking in the shop to someone who was petrified about running fillets- I knocked together a couple chunks of ply, ran a fillet and taped it, in about 5 or 6 minutes- he was amazed at how simple it was, and no longer afraid- Scarfing plywood is the same thing. In fact, ALL of it is- you can only make ONE joint at a time- make it the best you can, then move on. If it sucks, junk it and do it again. And you are right- you can repaint later. As a home builder you can do that- I can't - a customer wouldn't allow it. But asome of my early stuff wasn't near what I do today- in fact, the very first boat I ever tried to build, I looked at, then burned.

Here's my long boards

[John Burritt]

Charlie & I are replying at the same time.  Ditto to what he's said plus a few additional ideas.  For starters, sand off any hard edges on the tape, being real careful not to sand into the tape strands crossing the joint.  Then fair the tape edges with epoxy thickened with microballoons/West System Microlight or equivalent - easy sanding w/ almost no edge.  Don't be bashful about fairing out a long ways.  Use a WIDE knife.  This is just like doing seams in sheetrock.  The goal is to get any unavoidable high areas to blend in as unnoticably as possible.  This may take more than one coat.  Then sand w/ your long board, looking for shiny areas that don't sand out.  Fill them & sand again.  You set your own limits as to when it becomes obsessive.  The payoff is when the 3rd (or more) coat of paint looks pristine & only you know where the flaws are.

[Guest Dennis M]

Charlie and John,

Thanks for the information. I will tuck that away for future reference.

I did use the scraper quite a bit -- it does a very fine job taking down tape edges and I did fair those seams about 3 inches out from the seams. All in all, those places don't look too bad, but the dishing in places does, and I will have to remember Charlie's advice to leave well enough alone until the end.

Charlie, this is my third boat in 10 years and if I built for customers what I build for myself, I would starve or become proficient. Problem is, I don't have the money or the long suffering wife to indulge my obsession to build and sail, although sailing is higher on the priority list than building. I never touched a woodworking tool or built anything until I was 40 and built my first boat. I've got a lot of catching up to do, to be sure. Heck, I'm just happy that I've got all my digits and that every boat I have built has not leaked, has sailed well, and has looked reasonably similar to what the plans called for. .  

[Guest Dennis M]

Charlie or anyone else,

It is a little late for me, but I would like to know the secret of making a non-sagging fillet that will be taped over. On my boat, I was not consistent -- some of the seams came out fine, but others did not, and I cannot remember what I did differently on one seam than the other. Particularly problematic were the vertical fillets on the side tanks and transom. Also, when working a tape on a wet fillet, is it possible to work the tape on without brushing waves into the fillet? How do you do this? Do you wait to tape when the fillet has gone a bit tacky or do you do it immediately after it has been laid down?