1 Aft panel = Two evenings work

The oak battens, chine and keel that I was going to glue the aft bottom panel to were all tarnished from just being open to the air. It took most of the first evening and 3 belts (40 grit) on my belt sander to remove all the tarnish and leave nice clean wood to glue up. New belts are cheaper than the added time it takes when you persist in using a dead one, and dead ones burnish a surface. That's not good for gluing.

I'd gotten an attachment to allow me to connect my bosch sander to a vac, so there practically no mess.

I clamped a few guide blocks in place, and put in a few locating screws. This allowed me to consistently replace the panel. Then I marked up the places for all the screws, it takes long enough that you don't want to be doing that while the glue is setting up.

The next evening I coated the oak in neat epoxy and then pasted on micro fibre mix. A little careful lifting and the bottom panel was in place.

There's ¾" screws every 3 inches on the chine and keel and every 6 inches on the 3 battens. Add in the screws on the transom and you suddenly have about 100 screws. Two 18 volt drill/drivers means that you don't have to keep swapping drill bit/driver bit.

When I get home I'll see how well it all went.

Even so it was well dark by the time I finished, my builders site lamp is getting a good workout these evening.

More sanding this evening to start the aft panel on the other side.

That was a PITA

First, I will refer to a previous post boats-are-easier-than-carpets

I decided that it would be better to remove the first laminate, and replace it with a correctly sized one, rather than try to just add more laminates and fair them down.

There is a concern that White Oak does not Glue up well with Epoxy.

I am no longer concerned about this. My Epoxy glues my White Oak just fine.

The only way to remove the laminate turned out to be cross cutting it down to the glue line every 1/2 inch or so, and chipping it out with a chisel, just like cutting a housing for a lap joint.

Even doing this, in most places the wood did not come off at the glue line, A sander with 80 grit will tidy up the mess this weekend.

I used some scrap ply to see how much extra material I need on the chine to ensure that the side and bottom planking meet at most at a 180 degree angle. It's about 5/8"

At least I think know what I need to do now.

I suspect some more time in the Thinking Chair before I set to it.

It's been a while....

It's been a while.... I was doing exams, so it most of my "free" time was spent studying. Now that that's over for another few months, I've made some progress on the boat.

I have glued the CB case to the Keel. This fun, as you have to glue the cb case to the keel, and to the frames that cross the keel for and aft the CB case. It has to be strong, as the CB case must not leak, and will be one of the attachment point for the main sheet. Once the epoxy clock starts ticking, you can't hang about.

The CB case and bedlogs slot into the keel like a through tenon, just a very very big tenon. I slid the for and aft frames out a few inches, coated the CB case with thickened epoxy and slotted it into place. A few clamps brought it up snug. Then I pasted the ends where it would meet the frames with more epoxy and slid them back into place. These frames also needed epoxy where they joined the keel. It's all dry now and looks rock solid. Bronze screws will follow.

Then I glued and screwed the keel and the remaining frames, and glued and bolted the keel to the stem. (the bolts are home made from bronze bar a good quality die cuts threads in bronze without too much trouble. Don't cheap out and buy a cheapo tap and die set. Just buy the sizes you need. Life is hard enough without cheap tools)

D

It seems ok....

The CB case seems to have glued up ok.

I tidied it up today, added a few bronze ring nails for good measure. An oversized nail set allows you to smack these down flush without leaving hammer marks all over the place.

There was a hole to be drilled through the Oak at the forward end of the case the would have been whole lot easier to drill before I put it all together. The main problem was not drilling the hole, but cleaning up the break out from the drill bit. Since the line to raise the Centerboard is deadended through this hole, a little rounding of the sharp edges was required.

It's amazing where you can fit a dremmel.

Next step is the keel. I need to clamp it in place, and tidy up the CB bed logs to fit. Then I have to cut the slot for the CB through the keel.

That's one of those jobs that if you mess it up, there really is nothing else to do but start again with a new peice of wood. An a clear 4" x 1 1/8" x 12' is an expensive peice to mess up - never mind the time it took to cut and plane it.

Again, wish me luck.

Epoxy - A batch gone off

I started to glue up the Centerboard case today. I sanded the Oak and precoated it with epoxy.

Then I mixed up a batch of epoxy and filler, but while I was working on one side of the CB case, the remaining epoxy and filler was just getting warmed up.

When I went back to the mixing cup, it was hot, really hot, and had a big solid lump in the middle.

By now I had a half glued up CB case, and no epoxy ready. I mixed up a second smaller batch as quickly as I could, but still making sure I stirred it enough. So now I have to wait until tomorrow evening until I can see if it glued up OK.

Wish me luck.

Glassing Pictures

First up is my epoxy stir stick. Add a cheap battery powered drill and a good pair of protective goggles and you can go to town on stirring your epoxy.


Here you can see the corner where the glass lifted, I have cut away the lifted glass. I will sand this down and patch it up later.

When you add the epoxy, the glass becomes almost transparent. You can see the pattern of the weave, which apparently is about right. Too much epoxy in the first pass, and the glass will float off the ply.

Alway wear overalls, goggles, gloves and impermeable shoes when you start slopping epoxy around. The stuff gets everywhere.

Imagine if these had been sneakers, I might have found out later when I tried to take them off that the epoxy had soaked through and bonded my shoes and socks to my feet.

Centerboard case in progress...

The first glassing went well.

It's amazing to see what was a white opaque glass cloth become transparent with the application of a litte epoxy. The grain of the ply looks wonderful. I still need a second layer of epoxy to fill the weave. Apparently that's the way it should be, too much epoxy in the first pass, and the cloth floats off the wood.

I need to fix a corner where the glass lifted a little. I see my first practice at lapping glass cloth. Wish me luck.

D

Starting the Centerboard Case

Now that the new shed is in place, and all the boat parts are out of the kitchen (really) I've started back at work on the boat. I have more free space in the new shed, then total space in the old shed.

I took one side of the centerboard case and made an attempt at glassing it. Later today I will know how well it went. It's like the good old days of film cameras, when you had to wait to see the result of your work.

I had no idea of how much to mix, but since I was working on a small area, I was not too worried about the epoxy setting up while I mixed up more. I can see that for a large area, having an assistant to do the mixing would help.

I had left the cloth long around the edges of the plywood panel, but as I squeeged in the epoxy, the weight of the hanging cloth was causing the it to lift just inside the edge of the plywood, in much the same way as if I was trying to glass a right angle, once I trimed the cloth to an inch or so, it was fine.

Now I simply have to wait till it sets up, and see if it had made a good bond, or not. Then I'll bang on another layer of epoxy and see how it all looks.

Pictures will of course follow.

Mixing Epoxy

I took a tongue depressor (bought by the box) and a disposable chopstick.

I Cut about 4 inches off a chopstick, then cut the tongue depressor in half. Taped them together to make a long narrow spade.

I put the chopstick end in an old cheap variable speed electric drill, and Voila, one gloop mixer.

When adding Silica and Glass Beads to the mix, I folded them in by hand first, then mixed it with the drill.

I wore gloves, a face mask, goggles and a boiler suit and did this in a shed.

I do appreciate that grabbing a handful of trigger on the drill would result in a hazardous epoxy spray.

I intend to get a chuck for my electric screwdriver, since this has a fixed and slow rpm.

I suspect this would not be great for a clearcoat, as you stand to introduce to many bubbles into the mix.

Disclaimer: If you try this yourself, take all precautions you deam necessary. This has the potential to go horribly wrong. If you do not understand what will happen if you grab to much trigger, then sit down and think about it until you do understand. All of the ingredients in an Epoxy Gloop are harmful to you in some way or other.

Fun with Epoxy

In the end I went with GRS for my epoxy. They were very prompt about delivery.

I mixed up a small batch and epoxied some glass cloth across two peices of ply. I let it set for 24 hours and then tested to destruction.

With a lot of abuse, the cloth delaminated where boards were joined together the. Not easily - I was jumping on the boards where they were set up against a step. The plys actually separated.

In addition I glued two scrap prices together with thickened epoxy and a very quick and dirty fillet. After much jumping up and down, I managed to break them apart - the wood broke, not the glue.

I am quite certain I could do a much better job, both of glassing and gluing, so I have every confidence in this Epoxy stuff. 8-)

Next tests,
* Gluing Oak to Ply.
* Gluing Oak to Oak.
* Glassing a trailing edge.

Ruining Wood

I'm getting to the stage where I will start assembling the various odd shaped bits of wood onto a frame to make the skeleton for my boat.

In order to do this I need to build the Center Board Case, as two of the frames but up against this.

The Center Board case needs to be glassed. Since I'm making up the Case, it seemed appropriate to make up the Centerboard at the same time.

This means I need to Shape and Glass the Center Board, and Glass the Case.

I have never used Epoxy before for much beyond fixing the pendulum of a clock - please don't ask. So I reasoned that I would make up a test rudder from cheap ply instead of the good marine stuff, and glass it. This would be a learning experience, and I would not ruin anything expensive.

Along the way I figured out the following

* Prime the epoxy pumps by pumping out a little into a scrap cup and bin it. It means wasting a little epoxy, but not nearly as much as if you pump out too little hardener and work everything up only to find it doe not set.

* Epoxy goes a lot further than you'd expect. I made up what I thought was about half what I needed for my test piece only to have twice what I needed.

* How to glass the trailing edge is not obvious - try this link, go to the foils section - mothboat

* You can use the glue lines in the plywood to keep you rudder or center board symetrical.

I made a lot of mistakes, which was good, it meant I learned at least what not to do.

Getting Epoxy in Dublin

Prices in EUROs, as converted June 07.

Note: DiscountMarines info is from their OLD web site.

As far as I know this information is correct as of today 6th June 2007. This is not a comprehensive list. If this infomation is incorrect, or you have another supplier that I could add to the list, drop in a comment and I will try to update the list as and when I have time. Free information is worth what you pay for it. If you are buying large quantities, go do some further research 8-).

Epoxy and boat shows.

Currently trying to source epoxy now in Ireland. I will post a table here soon with prices, delivery, and landed cost per liter.

I'm also off to the Beale Park Boat Show on the thames this weekend. Expect Pictures.

I've cut most of the plywood peices that I traced out on the 18mm ply. You really gotta love a decent JigSaw.