Replacing backing to coamings

[Bob Perkins]

Mike,

Thanks for the good info on the trailer.. I'm modifying the one it came with to have 6' 2x6 carpeted bunks now. It has a couple of rollers for the keel... But another bunk in the middle is not out of the question.

I'm hoping the vacuum bagging goes well. Going to do one stringer today.
Fingers crossed!

[K.C. Walker]

I agree with Mike that a good trailer is paramount. I think a lot of damage and softening of these boats is due to trailering because of the flat planing hull. I used two carpeted 2 x 8's 10 feet long as the center support. I built a cradle into my trailer so that these match the hull contours and extend from the transom forward. I have one roller forward of that about 3 feet back from the bow knuckle. I have a 3 inch space between the center support boards and the boat goes on the trailer like its on rails.

There is quite a lot of evidence of hogging/depressions in the flat areas from the center board to the transom on these boats, like you've noticed on your boat, which is likely due to sitting on trailers. When you go to fairing the bottom, this is likely where you will spend the most time. I figured that I would span this area with my support bunks and not leave any localized pressure points.

I got talked out of Anderson bailers when I did my overhaul. There have been times since when I wish I had them installed.

[Bob Perkins]

Hey Guys,

If you get a chance - can you post pics of your trailer?

I'm not sure I have a lot of choices out of the gates with ours. It is a single rail trailer with an axle.. But I'm pretty sure I can get things supported up right with it.

Today's bagging of a stringer went well.

Layout of Balsa core (I had extra from an old project)
http://daysailer3033.shutterfly.com/pictures/29#29

Staging of bagging, peel ply fabric and breather fabric
http://daysailer3033.shutterfly.com/pictures/29#28

Full clamping pressure
http://daysailer3033.shutterfly.com/pictures/29#27

Pushing flat spot out while the stringer sets... just in case it will help!
http://daysailer3033.shutterfly.com/pictures/29#30

Probably can't do the second stringer until next weekend...

We *almost* have enough repairs completed to give it a test sail.
Need to clean out the centerboard trunk and fair/paint the bottom first.

[K.C. Walker]

It is a little difficult to see in this photo. What I did was build a cradle with 2X8s on edge and then attach the 2x8 bunk boards on top of that. To match the contours of the boat I put shims between the cradle and the bunk boards. Because my boat is much stiffer in front of the seat tanks, that's where I put the outer bunk boards.

Yeah, the EZ Loader trailer was for a deep-v powerboat originally.

[K.C. Walker]

Bob, It appears that the mastic sealing tape that you are using for your vacuum bagging is much wider than what I got from LBI here in Groton. What I got was half-inch and I did have trouble getting a good seal. Is what you are using mastic tape? And, how wide is it and where do you get it?

I made a vacuum set up from Joe Woodworker, as well.

Thanks!

[Bob Perkins]

Hi K.C.

I made the Joe Woodworker setup for veneer work. For boat work - it is 100% duty cycle for vacuuming...

When I first started bagging, I used the yellow vacuum seal stuff, special bagging, and all the other Marine industry stuff... big waste of money..

Now I use. 3-6 mil poly sheeting from Home Depot, Gorilla duct tape and a clay like window caulking called Mortite for sealing leaks.

Jo-Ann fabrics sells 100% polyester dress lining (used as Peelply) and I use quilt batting for breather fabric. When they have the 50% off coupon - it is all a good deal.

I used the slow System 3 epoxy because it was pretty warm here.. but I wish I used the medium. The pump will be on all night because the glue has not cured enough just yet.. Hopefully it will be done in the AM.

Talk soon

[K.C. Walker]

Bob,

This is all great information on vacuum bagging for boats! Thanks! Duct tape, of course... One can't hold anything together with that stuff.

Yes, I used the slow cure and had some overnight 100% duty cycle vacuum bagging experiences. I wanted to use the slow cure to give myself enough time outside on a sunny day. However, then the temperature would drop in the evening and overnight and the stuff just took forever to cure.

[Bob Perkins]

Here it is - completed.

Couple of small spots with bridging. But overall - tighter than I could get w/o vacuum by a lot!

http://daysailer3033.shutterfly.com/pictures/31#31
http://daysailer3033.shutterfly.com/pictures/31#32

I used 2 layers of the 6" wide glass tape. It seems thinner than the polyester I removed. However, when I step or push down, the entire area moves. With the stringer gone, you could feel the hull just bulging around your hand or foot. So mission accomplished so far.

We'll see if we got most of the flat spot out once the hull is flipped..

[Mike Gillum]

We're racing #2772 at Lake Yosemite this weekend and I'll get several photographs of the trailer with and without #2772 on it as an article for the DS Quarterly about trailers is needed!
I use a black indoor/outdoor carpet that comes from Home Depot. Its inexpensive, soft enough not to scratch the hull, and durable enough to handle moisture and UV damage.
Centerline support is a preprimed wood 2x6 trim board that I stumbled across locally several years ago that is smooth on three sides and rough on the fourth side. That rough side gets turned down to the road.
The preprimed wood 2x6 trim board is limber enough to easily contour to the bottom of the hull but strong enough that I can stand on it when retrieving #2772 at the launch ramp.
I used doubled 1x6 previously before I found preprimed wood 2x6 trim board.
Side supports are a preprimed wood 1x6 trim board screwed to a piece of 2x2 Doug Fir allowing the two pieces to easily conform to the hull shape while still being strong enough to withstand any abuse.
After all the wood pieces have been fitted and I'm satisfied then a couple of coats of paints are applied giving a finished appearance and a little protection to the wood from water and road grime.
The trailer under #2772 is the trailer frame I salvaged originally from DS #1154, added a recycled axle from another trailer, new fenders, and then welded a much of steel plate & TS (Tube Steel) brackets & members to create the mounting brackets for the supports and Mast Support at the bow.
The Mast Support has a winch to pull #2772 forward on the trailer as well as being used in conjunction with the Jib Halyard to pull the mast forward to attach the Forestay. It also carries the spare tire.
Last year we drove somewhere around ten thousand miles between our Thistles and Daysailer. A great trailer that gets us and our boat safely from home to regatta and back each weekend at 55-80 mph is paramount!

[kkearns]

Bob,

Great pictures of your restoration. Thanks for sharing them. I have DS #1827, almost identical to yours. I wonder, if you have a moment, would you be willing to give a step by step explanation of your stringer replacement? I have no stringers in my boat, and I want to install some to stiffen the hull. But I must say in advance, I have no significant experience with this type of job. I noticed you used a vacuum to achieve the fit. Is this a device that could be rented? Be candid ... is this job beyond the range of someone like me with no real experience in fiberglass other than simple cosmetic repairs to a variety of boats over a 30 years span of sailing? Should I hirer someone to do it?

Kevin

[Alan]

I'll echo Kevin's question. I've found, as nearly as I can tell, all of the threads related to vacuum bagging, but there isn't much there. (There's a huge amount of information on stringers generally, though.)

Looking at the photos, I think I see a small shop vac with possibly a special-purpose hose and end fitting. I could probably substitute stuff laying around my garage, but then the real question is: Does the fitting go inside the plastic and on top of the fiberglass? And how does that not suck up the resin?

OK, that's two questions, but you get the idea...

[GreenLake]

A nice step-by-step description specific to stringer replacement would indeed be nice, if Bob feels up to it.

In the meantime, I located some background material.

Short Video on vacuum bagging
Detailed PDF on vacuum bagging
Vacuum bagging supplies (catalog)

That should give you a start.

[Bob Perkins]

Hi Everyone,

I'll put together a step-by-step instructional piece (probably on a different thread just so it is easily searchable this weekend)

I'll ask the Mrs. to take pictures as I go along so that you can get an idea of what I'm doing.

Vacuum bagging is a lot simpler than it looks.
But... You need a real vacuum pump, which is a bit of an investment if you do not think you will use it that much. People say you can use a vacuum cleaner... you will fry it. They are designed to have air flow over the motor while vacuuming. The bagging process means no air flow...
I'll go into that on the weekend thread.
thx

[Alan]

GreenLake, Bob,

Thanks. This is a really interesting thread, even if I do have a DSII.

[Bob Perkins]

All,

I created a new thread specific to vacuum and stringers.
http://forum.daysailer.org/forum/viewtopic.php?t=3649

Hope this helps