Epoxy Woes

I’ve always said if anything can go wrong, it will go wrong with me.  This has always been my life experience.  Maybe you feel the same way, maybe everyone feels this way, but I have proof.

When attempting to sand the hull panels, I noticed the second coat of epoxy lifting off the first coat.  At first, I doubted what I saw…but the more I sanded, the more the truth revealed itself.  I had an adhesion problem and it was real.

What steps did I take when applying the epoxy?

1. I waited 24 hours after the first coat before applying the second coat.  Please realize this is really slow stuff, so even after 24 hours, the first coat was tacky.  I presumed I would be getting a very good chemical bond between the coats.
2. I applied the second coat and then waited 48 hours before sanding.
3. My shop was heated to 65 degrees.
4. No other activity occurred inside my shop.
5. My shop heater is a closed system natural gas shop heater with venting out the roof, hence I was not adding moisture to the air through the heating process.
6. When sanding, I detected some flaking.  After more sanding the problem revealed itself as an adhesion problem.  I included the photos above to help others see my results.

Summary:

After sending photos to Ductworks, I called Chuck to discuss the problem.  He was very apologetic and immediately took care of the problem by sending me out new Marinepoxy.  I appreciate Chuck’s willingness to make things right before I even had a chance to ask him.  I don’t blame Ductworks at all for this issue.  They will be communicating with their supplier to discuss the problem.  Based upon this issue, I will be using regular Marinepoxy for my Skiff America.   Though initially very discouraging, I am very fortunate I detected the problem at this early stage of my build.  It would be heart breaking to getting deeper into things before realizing a problem.  Life is all about problem solving…this is no different.  

Let the Epoxy Flow

Well, not so fast.  Before I can start to epoxy, I need to get organized much like a surgeon would prior to surgery.

This is my setup.  

1. Epoxy
2. Wood filler, Silica filler
3. Roller with thin foam rollers
4. Squeegee
5. Alcohol
6. Rags
7. Gloves
8. Zip locks for fillets
9. Stir sticks
10. Cups, spoons
11. Wax paper

I also cover (2) 2 x 4 x 16′ boards with duck tape to use as an epoxy bench.

The epoxy I am using comes from Duck works.  It is a new formulation.  Much safer from a health perspective, much longer open time and if that isn’t enough, it contains two U.V. inhibitors.  Did you get that?  You don’t need to over coat this with paint or spar varnish.  That’s what the experts say.  I decided to give it a try.  Chuck has had a piece exposed to the Texas sun for 10 months with no signs of deterioration.   He indicated this is better than any spar varnish he is aware of.  It’s called DuckWorks DWX Epoxy.  I’m no chemist…but I like what I heard, so I’m moving forward with this new formulation.

Summary:

My standard approach to epoxy application is somewhat different than others.  I mix up the epoxy, squeegee it around on the board (if it is a large board), then I roll over the epoxy to even out the coat.  I then finish things off by tipping the epoxy with a cheap chip brush to smooth out the bubbles.  This system works well for me.  It’s all about finding a system that works well for you.   

Construction Frame

The construction frame supports the hull pieces while you align the side panels.

I laid out the 2 x 6 and marked where I wanted to cut the dados for the aft cross member.

There are certainly many other ways you could accomplish this joint.  You could also simply buy the metal brackets specified in the plans.  I decided to cut them with hand tools because I was too lazy to install dado blades into my table saw.

I first screwed the 33″ cross member to the 16′ 2 x 6 and then added the aft cross member.

Don’t forget to cut out the corners of the aft cross member to allow clearance for the chine panels.

Now shim and confirm 3 times that all cross members are level.

I used several pieces to properly support and level the frame.  Once all cross members were level, I marked all shim locations incase I accidentally kick one out of position.

Summary:

This isn’t hard stuff folks.  If you have ever dreamed of building your own boat, buy Kilburn’s plans and build one with me.  I’ll lead the way and make all the mistakes for you and then show you how I fixed them.  

Dimensioning the Plywood

I’ve been busy cutting out parts while I wait for the epoxy to arrive.

The plans call for doublers when joining two panels.  This approach is simple, effective and attractive.  Kilburn asks the builder to cut a 15 degree angle on the long edges.  This gives the doubler a very attractive, eye catching appearance.

I used one half of the front bulkhead to trace and create the second half.  These two pieces will be joined with a doubler.  Kilburn has utilized nearly every square inch of a 4 x 8 to create both front and rear bulkheads, a doubler, two cabinet bottom corners and the front filler board all out of a single sheet.  Very clever!

This is the doubler to join the upper end of one side of the front bulkhead.  You leave it 3/4″ shy off the inboard edge to allow for solid wood edging.

I designed and cut the windows at this stage while I had the panels lying flat.  The front window is sized in accordance to plans but the rear window was dimension up a bit.  It is 1″ taller and 2″ longer than the standard window.   I felt this made for a more balanced looking cabin.

Summary:

 I will now put my attention toward building the construction frame while I wait to receive the epoxy.  The plans have been easy to follow and very clear.   I’m very impressed with Kilburn’s attention to detail.  This is a surprisingly simple boat.  In fact it’s so simple I believe it might actually work.  

 

Cutting the Hull and Transom

Measure twice and cut once.  Or, measure 8 times because your so nervous and cut a couple of times as you sneak up on the line.

It took a little courage to begin making this cut.  I felt good about the lines…it’s just getting started and knowing the consequences of miss cutting that makes one nervous.

After a while, I was cutting away like I meant it.

Summary:

I now have the 3 hull pieces and the transom cut to size.  I took a Shinto rasp and smoothed the transom top arching line a bit to smooth my irregular cut.  I will use a 1/8″ roundover bit on the top lines of the transom.  It will then be ready for epoxy.  You have probably noticed I’m dimensioning the plywood before applying epoxy.  This is simply a matter of personal preference. I like to make the pieces before I epoxy, so this is the sequence I’m following.  The plans call for epoxy first and dimensioning the pieces second.   Either way works, just follow the approach your most comfortable with.  

Layout Tools

There are a few tools that have really helped me layout all the lines for this build.  I will show the essential tools below and explain their purpose.

These tools have proved very helpful:

1. The 48″ T-square.  This allows me to make perpendicular marks all the way across a sheet of plywood.  This has been extremely helpful to keep the layout lines accurate.
2. The 36″ straight metal ruler.  Handy for measuring shorter lines.
3. 12′ tape measure.  Ideal for longer lines, like 96″.  If you are buying this tool for this build, buy a 25′ tape measure.  I already own this 12′ so I’m using it.
4. 6″ trisquare.  Helpful for scribing short 90 degree markings.
5. A fat pencil.  Lays down a thicker line you can cut from.
6. A thin pencil.  For markings that require more accuracy.

Summary:

The most important of all these tools for me has been the 48″ T-square.  It has made the layout  markings fast and accurate.  It’s so fun to mark this beautiful plywood and watch the lines take shape.  Going from paper to actual wood pieces is a very rewarding process to observe.  You think you have a feel for the proportions, but until you cut the wood you’re never quite sure.  Once you cut, it all starts to make sense.  I’m having a total blast here folks.

It Officially Begins

Skiff America 20, here I come!

Well, I guess I’m sort of committed now.

 This is my wife’s Ford F-150 with $1,543 dollars worth of plywood sitting in the back.  I actually purchased 17 sheets instead of the 14 sheets as specified by the plans.  I will be modifying the cockpit to sleep two teenagers and I might be adding another 1/2″ panel to the cockpit floor for increased rigidity.

Summary:

This is all Okoume B.S. 1088 plywood, the best stuff on earth.  I’ve already spoken to the wood, explaining where we are headed and how I intend to use them most appropriately…for the construction of a Cruising Vessel.  I’ve agreed to be kind and not swear, they’ve agreed to take shape and act upstandingly.  I think we’re all going to get along just fine.

Temporary Frame #1

For frame #1, I erased the previous lines on the plywood and sketched out the proper location of all members.

Now don’t think I didn’t spread this glue out with my finger.  That would not pass the ‘ham n egger’ standard.  No, my dad would be very disappointed in me if I didn’t spread this out smooth, right up to the edges.

This frame goes up near the front of the boat and hence is much taller and narrower than frame #2.

Summary:

Really easy folks.  Just layout the lines, make your cuts and screw the hole thing together.  I was forced to move a member or two during the process to maintain proper alignment.  As you screw slippery sticks together, things want to move on you.  Just take your time and make any corrections needed.  I love looking at these frames and dreaming of the final hull shape.

Temporary Frame #2

Tempting fate a bit, I decided to build the temporary frame #2…just to see if I could.

I traced out the position of all the frame members onto a 1/4″ sheet of plywood.  After carefully checking all the measurements and noting the 1/4″ drop of the lower cross member, I began cutting the frame pieces.

Short pieces attach to one side of the frame, with longer pieces attaching to the opposite side of the frame.  Don’t forget the glue, you don’t want these pieces to move on you.

And…there it is!  The aft shape of the hull can easily be seen from this frame.  It is very exciting for me to see the lines take shape.  I’m excited already!!  Now, if I can just get Jennifer (head navigator) to sign off on the purchase of all the plywood and epoxy.  She is still questioning my new drift boat purchase…it hasn’t even been in the water yet.  I know…I have a boat problem and some day I’ll address it.  But for now, “just let me be in love”.  

Scarfing Jig

I like to begin a project by sneaking up on it a little bit at a time.  This leaves me bail out options if needed.  

I even tried this on my wife, but she said NO, so I married her without any further fussing.

With this in mind, I have decided to build the scarfing jig and the temporary frames for a Skiff America 20.  These two simple projects allow me to start without really starting or fully committing to the build.  If I continue feeling good, I’ll keep moving forward.

With that in mind, let’s discuss the scarfing jig.  I have cut scarfs by hand and it’s a difficult process.  If the angles are not cut accurately, your scarf can fail.  A failed scarf is no fun…this jig will help me get it right.

Kilburn Adams included plans for building a simple, straight forward scarfing jig.

I must say the plans produced by Kilburn are very impressive.  The level of detail and attention paid by Kilburn is unlike anything I’ve ever seen.  In fact, these plans are so good you should buy them just in case you ever decide in the future you want to build this boat.  This level of intelligent design is rare in our modern throw-away society.  

I started by lopping off an 18″ section of 3/4″ baltic birch.  You gotta love my home made trisquare…much warmer to touch and lighter to handle than cold aluminum.  And yes, It’s square.

A 3/4″ x 1″ fence is added to the cutting end of the jig.  I counter sunk the screws to keep the bottom of the jig flat.

 

Then I built the 3/4″ x 3/8″ strip to key the jig to the table saw slot.  Here I’m checking the fit.

I then glued the strip to the bottom of the angled jig.  After this dried, I cleaned up the squeeze out with my shoulder plane.  A shoulder plane can work miracles when you have a need to remove material from an inside corner.  After a few passed, the jig once again moved freely through the table saw slot.

I used a jack plane to flush up the clamping side of the jig.  This creates a flat clamping surface for holding the stock lumber to be scarfed.

I checked the angles with my pocket square for accuracy.  All looks good.

Summary:

It took me just over an hour to build this scarfing jig.  Now when I need to scarf solid stock into longer pieces, I can accurately cut the scarfing angles.  Many thanks to Kilburn for providing this as part of the Skiff America plans.  This is a very handy jig to have around your shop.