May 2018

This month it's all about fiber-glassing or encapsulating the hull at least one side.  I've already made a few mistakes and will walk you through what went right and what went wrong and how I'm going to do it better on the other side.  First of all, I made the decision right away to break the project into 3 parts.  The port, starboard and transom.  I'm starting with the port side because it is closest to the work area and will have the least running around.  I believe it would be nearly impossible to encapsulate the entire hull in one go especially for a small crew and we just don't have the experience to get the job done quickly.

We have two types of glass; 2 oz mat glass that is 50 inches (1.27 m) wide and 10 oz woven cloth that is 60 inches (1.52 m) wide.  The cloth will lay over the mat hopefully giving the finished project a smooth finish.  I cut 0.2 inch (5 mm) strips from  standard 2x4 construction lumber to use as battens to temporarily hold the glass in place on the hull.  I used long staples from a standard T50 manual staple gun to attach the battens to the hull.  My intention was to only place battens at the top edge of the sheets so the glass will hang loose and when the epoxy is applied, the glass will then be able to stretch with the aid of gravity.  The two different widths will make this impossible to achieve so my next idea was to place a batten at the top of the mat and then at the top of the cloth and sneak the battens holding the mat (and covered by the cloth) out when I apply the epoxy.  Greatest plans of mice and men oft' go astray...

The first step is hanging the two layers of glass (2 oz mat and 10 oz cloth on top).  I made a vertical  spooler for that shown below and discussed earlier.  It turns out that the mat glass will not come of the spooler without ripping apart and large sheets can not be handled because the mat will fall apart under its own weight.  I did not expect that since I've never worked with such large sheets.  I expect that if you had 10 or 15 people handling it in a well coordinated manner you could make it happen but who has that kind of man power.  So the first step failed and we resorted to laying the roll on a long table and cutting 10-12 feet (3.3 m) at a time and hanging those one piece at a time.

Spooler was useless for the mat and not that handy for the cloth.  Your better off unrolling on the table .

Three runs of 10-12 foot pieces worked very nicely.  It turns out that the mat is very stiff as well as fragile.  It will not make turns along the hull.  Short pieces are necessary to make these turns so this turned out for the best.  I have battens along the top edge of all the runs and I've overlapped the mat about 1.5 inches (30 mm) which just covers the battens.  These would have been easily removed if they were not later covered by the woven cloth.  The next step was to run out the cloth and hang it on top of the mat.  The spooler actually worked very well for the first run at the gunwales nearest the floor.  We had three guys working and we were able to get the cloth up in one piece without too much pulling of the weave. Again, we stapled battens at the top edge of the cloth and proceeded with the next run (again overlapping about 1.5 inches (30 mm)).  The next run did not fair to well.  We had the cloth despooled but then it was necessary to lift it in place way beyond our reach.  We would have done better rolling off what we needed folding it as we went and then place the folded cloth on one end of the boat unfolding it along the length of the boat.  That is what we'll do on the other side.  Anyway, we hung all three rows of cloth and stapled battens at the top without regard to the battens that were trapped underneath holding the mat and that was our biggest mistake.  This method leaves battens that are holding the mat inaccessible.  I thought that I could epoxy around those areas and once the glass was sticking to the wood I could peel back sections and pull the battens out.  That might have worked but it was apparent that it would be pretty messy and risked over stretching the weave.  Truth be told it took us over 4 hours, one evening, to hang that glass and we were pretty tired and itchy.  I decided to leave the problem for another day.  Never try to work through something tired.  A few days later I tackled the problem.  My solution was to put additional battens below the now hidden battens holding the mat glass in place.  These new battens would hold both the mat and cloth.  Next, removed the battens holding the top of the cloth and draped the cloth (~10 inches) down over the newly installed battens.  This allowed me to remove the hidden battens that were only holding the mat glass since the newly installed battens just below were holding both the mat and the cloth.  I then undraped (straightened it out) the cloth and reapplied the battens at the top of the cloth.  I repeated this on the second layer.  Now I only have battens at the seams (covered only by the 1.5 inch of overlap) of the cloth and 10 inches down from the seam (fully exposed and easily removed).  All the battens are now easily removed once the epoxy is applied.  I realize now that this procedure would have been simpler to perform in the first place and that's my plan for the other side.

1) Hang the three runs of mat glass with battens on top edge.
2) Hang one run of cloth with temporary battens at the top edge.
3) Add another run of battens below the battens holding the mat in the first run.
4) Remove temporary battens holding the cloth and drape the cloth down exposing the battens holding the mat.
5) Remove the battens holding the mat (the new battens below them are now holding the mat) and undrape (straighten) the cloth adding permanent battens at the top edge of the cloth.
6) Repeat for second run.
7) Third run is on the flat bottom area and does not pose much of an issue.

Stylized cartoon of the sequence used to install the glass.

Placing battens to temporarily hold the glass in place.  The batten shown on the right is holding the cloth around 10 inches down from the edge of the exposed cloth and right on the edge of the mat below.  At this point I was still working things out. 

Narrow strip of cloth being smoothed out and placed next to the keel stump.

This is before I removed the covered battens.  No way to do this during the epoxy application phase.  

Again, there are battens that will be very difficult to remove once the glass is wet.  I'm glad I found a better way.

More pictures are coming.  We plan to start wetting out the fiberglass Saturday morning (May 19).  I have a crew of 5 coming to help out.  There has been a lot of planning for this day. I'm sure that it won't all go smoothly but hopefully we have bought us enough leeway with good planning to have everything work out well.  Stay tuned.  I'll have someone take pictures of the process and I'll tell you what went right and what went wrong and what I'd do different next time.  There are always lessons to be learned.

May 19,
All preparation work has been completed.  My crew of 5 met at the house at 8:00 am Saturday morning for coffee and discussion.  We were working by 8:45.

We had one gal (my wife) measuring out epoxy and harder using a digital kitchen scale with a tare feature.  This in by far the easiest and quickest method for metering out epoxy.  One man was on top of the hull applying epoxy while two were rolling epoxy on the side of the hull from the ground.  After the two on the ground made it to the midpoint of the hull, we switched one to assist with the top of the hull.  I was assisting everywhere generally working seams and edges and assisting with epoxy delivery.

We started about a meter from the stern on the bottom.  We started out pouring generous portions of epoxy onto the to part of the hull where it is fairly flat.  We then moved the epoxy around with laminate rollers.  Later we found that this was not the best technique.  It is much more efficient to move the epoxy around with standard 9" paint rollers with 3/8" nap.  The laminate rollers are slower and can dig in creating ripples that hard to remove.  The ripples come from compressing the mat and glass.  It is important to take care of the paint roller covers and keep them working.  If they sit unused, they will cure up and get hot.  It will happen eventually and you need to be ready to remove the cover before it becomes a permanent part of the roller frame.  By cheap roller frames in quantity.  Do not buy cheap covers.  You don't need to buy the expensive ones but cheap ones will fall apart.

Always work toward the loose end of the glass.  The glass stretches when it gets wet and there will be some excess you will need to move to the edges.  I actually thought this would be a bigger problem than it was.  Where the glass was draped nearly vertical, there were very little issues.  Gravity helped keep the glass stretched.

This is from right before we began.  You can see one batten exposed and right above another that is just under the overlap where it will be easy to remove.

Similar to above.

That is Alfred Kuhn on the left and me on the right discussing how we are going to proceed.

On the left is Nick Robey and me on the right discussing the plan.

This is a laminate roller.  It's great for smoothing out wrinkles and working epoxy into seams  and edges.  I do not recommend using this roller for the general field work if you are wetting out multiple layers like we are here.

I took a hand held kitchen mixer beater and put it in a small drill press set on the lowest speed (~800 RPM).   It was a great time saver.  Worked wonderfully and probably made the day manageable.

Me demonstrating the mixer.  This was a dry run with no hardener.  I wanted to make sure the speed was correct and there was no splashing.

It's not all work, work, work.  When you get a creative, talented crew together, you had better expect a bit of fun.

Nick Robey doing a little clean up.  I supplied acetone for clean up.  Works fairly well.  You still end up with a film but that usually can be washed of with dish soap.

This our latest family member.  He loves to give us a hand in the boat shop. 

Caroline Whetham hard at work.  We used this floor squeegee to remove excess epoxy.  It worked but it was easier to roll over the area with a dry roller.  When I say a dry roller, what I mean is a roller where you have already used up most of the epoxy in it.  It is not actually dry.

We started out applying the epoxy exactly like you apply paint.  That was what everyone was use to.  Although this worked fine, it took many coats and a lot of mechanical work to get the glass wetted out completely.  The more you work the glass, the more distorted it gets and the less it wants to lay down nice.  We soon discovered that you want to get your roller almost dripping wet and roll only a short area without letting the roller dry.  A small area quickly becomes saturated with epoxy and you move to a new area.  Only after a section is saturated do you let the roller run 'dry'.  Use the dryer roller move excess epoxy around and push the glass against the plywood.  Remember, you want to see the weave clearly with no epoxy pooling on top.  On the other side, the glass will turn clear (mostly) when it is properly saturated.  There will be areas that turn milky and this is normal.  There are also specks that won't turn clear no matter what you do.  I think this is normal as well.  If you have too much epoxy, the glass will float to the surface and leave a gap between the wood and glass.  It will also leave a raised area that will need additional sanding and  when you sand that area, you will sand right through the glass and leave a void.   It is very easy to apply epoxy and fill the weave after the work is cured (or when it is almost cured and still sticky).  At that point you apply the epoxy exactly like rolling on paint.  

That is Al Kuhn surveying the work before beginning.  The for legged guy is Fig.  I think he's showing Al what to do.
  

Just finishing the bow area.  Everyone else is heading for the beer cooler.  I'll be right there guys.  Don't wait on me.

We had extra epoxy made up so I rolled on a second layer where the epoxy was still sticky but set.  

Dog help is always appreciated.   

That is me on the left in the red shirt.  I'm using one of the small plastic laminate rollers which is great for edges, crinkles  and especially seams where several layers are overlapped.  You can see that I'm working the edges.  On the right is Caroline Whetham using a normal paint roller to apply epoxy to the field.  Hey, we are almost at the end here.

A crew has to eat and we had no time to take a break.  We grabbed a slice when we could.

The day got warmer than I would have liked but we still did not have trouble keeping up.  By starting from one end of the boat and working toward the other, you can keep your leading edge wet while the epoxy cures behind you.  Make sure that you completely finish all edges and seams as you go or it will harden on you.  If you have a cool day or enough help, you can start putting on your finish layers of epoxy by rolling them on just like you would paint over the areas that have become tacky but not cured.  If the epoxy cures, it will have to be washed with soap and water before additional layers can be applied.  When the epoxy cures, an amine waxy residue will rise to the surface and will prevent bonding of additional layers of epoxy.  If the epoxy is still tacky, the amine will continue to rise to the surface of the new layer and it won't matter.  One more thing.  Do not sand until you wash the amine residue off, it can get embedded in the sanding scratches and will resist being washed off causing problems.

We will make a few changes when we tackle the other side.  I would like one more person to help meter out the epoxy, and we will rely more heavily on standard paint rollers.

May, 28

Time to clean up the edges and along the centerline of the bottom of the boat to prepare for laying glass on the other side of the hull.  I am feathering the glass back about 3/4 of an inch (2 cm).  I'll epoxy the fiberglass over the feathered portion and grind back smooth once it's cured.

Sanding the glass back 3/4" at the bow to allow overlap from the other side.  I'm going to add up to 3 additional layers of woven glass at the bow to provide protection from the inevitable extra wear expected there.  

Feathered the glass back beyond the rounded corner on the  transom.  

I had trouble with to small areas where the mat was overlapped.  No matter how much I worked these areas, I could not get the epoxy to fully saturate the glass and the wood.  I suspect that the epoxy was left too thick in these areas and cured just enough to inhibit saturation.  I check these spots and others  after the epoxy was cured by tapping on them with a piece of wood.  Sure enough, you could hear the hollow thwack instead of the solid thud expected at these two small areas.  Nothing to do but cut them out and re-glass those areas.  I found it pretty easy to use a sharp chisel for this procedure.  I went pretty quickly.

Just chisel around the edges and lift the bad spot out.

The other bad spot.  You can see some additional spots to the left and to a lesser degree to the right.  I extended the cut-out to include these areas.

I cut out a piece of mat and cloth to fit holes and saturated them with epoxy and laid them in.  I actually wetted down the wood first to make sure that the wood and the edges were wet.  You can see that the issues occurred where the mat was doubled (left) and quadrupled (right) on overlaps.  The uncured epoxy was very thick here probably causing accelerated curing.  I'll take extra care to remove excess epoxy in these areas next time.  

Lessons:

1)  Be smart about hanging the glass.  Keep overlaps to a minimum.  Mostly they ended up around 2 inches (5 cm) which is good.  There were some that were larger and these can be avoided.  Make sure the glass drapes.
2)  Make sure you have a quick and smooth method to measure and mix the epoxy.  Next time I'm going to use two people and two mixing stations with their own scale; one for the epoxy and one for the hardener.  Next to the hardener station I use an egg beater from a mixer set into the jaws of a small drill press set on a low speed.
3)  Apply epoxy with a standard 3/8" paint roller starting near where the glass is temporarily fastened.  Apply very liberally and keep the roller very wet until the area you are working on is saturated.  It will turn very nearly clear.  Then allow the roller to become 'dry' and go over your wet areas spreading the excess epoxy to new areas and pushing the glass against the plywood.  The cloth weave pattern should be very apparent and there should be no pooling of the epoxy.  If the epoxy pools, the cloth will 'float' off the plywood and leave a raised area.  It will require excess sanding and expose the cloth.
4)  Work the overlaps and edges with the laminate roller right after an area has been saturated.  Work the epoxy through the glass until the glass turns nearly clear.  Work edges until they lay flat.  It's tempting to staple the cloth around the edges but this will tend to also lift the glass off the edge because the glass does not like to make sharp corners.  Instead trim off as much as possible and let the glass lay straight down.  Curves can be handled in that fashion.  So if you need the glass to bend around a corner, make sure the corner has a good radius.
5)  If the epoxy is still tacky when you are finished or if you have enough man power, roll two to three layers of epoxy to completely fill the weave and a little extra.  Otherwise you will need to wash the cured epoxy with soap and water before you start the weave filling layers.  These layers go on just like paint.
6)  Trim all the edges with a sharp utility knife before the epoxy is completely cured.  It will be a lot easier and you can ensure that the edges are properly seated against the plywood.  If the epoxy is still tacky, you can always use a little fresh epoxy if the edge is being difficult about laying true.
7)  Take your time and do not panic.  Most mistakes can be fixed.  Check the weather forecast.  If it is going to be hot that day, choose another day or start very early in the morning.  Try to have fun.