Tech Tip Tuesday

I'm blushing. 

No, really  - blushing. 

How can you tell? 

I've been using epoxy.

Rather than lash frames, we've opted to bond the stringers to the frames with epoxy.  In this case, I happened to have a left-over kit of System Three's general purpose epoxy resin.  To create the adhesive, we have added fumed silica to the resin. (Note the dust mask that the student who was mixing the silica into the epoxy was wearing!  An excellent idea as you don't want to inhale the stuff!)  The System Three general purpose resin blushes a bit.  By that, I mean that it has an amine blush that rises to the surface f the bond joint.  This particular epoxy is amine based and the amine blush is a waxy coating that rises to the surface of the curing resin. 

This amine blush can raise havoc with the curing of finishes and the bonding of successive coats of epoxy if you want to apply them.  However, it is easy to remove this blush.  There are two tried and true ways.  One is with soap and water, the other is with household ammonia.  As we intend to coat the frames we're building with varnish or polyurethane before skinning them, we want to remove the blush to prevent problems with curing that can include retarding the cure or fish eyes in the finish.  You need to remove the blush before sanding so that you don't simply spread it around.

There are some resins that claim to be "blush free" - particularly clear-coat epoxies.  I tend to treat this with a grain of salt and assume that any epoxy that I use may have some amine blush.  It's a case of "better safe than sorry".

I'll tell you why I tend to be careful.   The first strip-built boat that I glassed with a particular vendor's epoxy said that I should prepare the surface before putting on a protective layer of UV filtering varnish.  I made the assumption that they meant sanding, and thoroughly wet-sanded the hull with water and fine-grit paper.  I then applied a good quality spar varnish with UV filters.  The next day, I went downstairs and touched the hull, leaving a finger print.  I figured that it was a bit cool in the cellar and let it wait.  I came home from work - same thing.  I let it sit two more days - a third finger print. 

After a call to the manufacturer's help line, I finally wound up removing the uncured varnish with solvents - a nasty, messy process.   I then prepped the hull per their instructions (ammonia and water) and then used their recommended proprietary coating.  I did have success, but learned a valuable lesson.

ALWAYS REMOVE THE BLUSH!

The Prep Work Has Begun

Fantastic Plastic : Redux

A few weeks ago, I put up a post about plastic kayaks. (see here) Matthew Housekeeper from Soundbounder made the following comment:

You make some good points. The plastics introduce many people to the hobby.

This is undeniably true, however, I do have some problems with this. I hate to make a generalization, but people who tend to buy the small, cheap, "cute" rotomolded kayaks, usually have very little training or backround with small boats before they buy them. On the water, these tend to be the people that I see out without a PFD on. They are also the people who can be found in the way of other craft that may have the right-of-way on the water. Sometimes, they are drinking large quantities of alcoholic beverages on the water. They also seem to be the ones who are out in conditions that may exceed their abilities. I doubt most people in these tubby little craft ("But it's as stable as a rock!") have ever deliberately tipped the boat and tried a wet exit and re-entry under controlled conditions, let alone poor conditions.

This is not to say that all people who are out in plastic boats or even these little plastic boats that I describe above are poorly prepared or have little skills. I'm just making an observation based on what I've seen. There are also popular sea-kayaks, whitewater, and whitewater touring boats that are plastic and are paddled by those with excellent background, skills and abilities.

The point here is that these small, inexpensive boats, bring boating to pretty much anyone who wants to paddle. But you should still learn what you are doing out on the water before you venture out and become a danger to yourself and others.

To be equally fair, the same can be true at the other end of the spectrum with the fanciest, most expensive wood or fiberglass boats - paddle, sail and power. They have the money to buy the boat, but not the skills to deal with the situations that may arise out on the water.

Bottom line : if you're going to be operating a boat out on the water, please know what you should be doing, and do it safely.

Tech Tip Tuesday

You will probably think that I'm off my rocker today, but bear with me. (Pun intended.) This post really goes along with my earlier "P-rule" post. As you know from some of my other posts I am working on a new project - a skin on frame kayak. Perhaps because I am an engineer (and bear of little brain), I like to be able to think about my boatbuilding a bit trying to make the method work better or easier. This is particularly true of new projects whether it be a new design or build method. It's really important to sit and think through the process before beginning. In boatbuilding, the materials can be expensive and the processes relatively irreversable. You want to head off your mistakes before they happen.

While most boat building books refer to the "moaning chair", where you sit after the mistake has happened and put the tools down so you don't either a) do more damage or b) hurt yoursef, I am of the Pooh school of thot and vote for the "thotful spot". It's pre-emptive in nature. It should be a quiet, comfortable space where you can work undisturbed. Sit in your "thotful spot" with a "restorative beverage" (Thanks, Greg Rössel!) and some books, paper, plans or whatever helps you visualize what you are about to do. Work it through however it works best for you before you actually go and do the work. I find this method to be very helpful. If you find yourself at an impasse, don't let the "thotful spot" become the "moaning chair" - go and find another resource or ask someone who may know. It works a lot better!

Tech Tip Tuesday : The "P" Rule

When building a canoe, there is a lot of time involved and a lot of different steps. That's not to say that they are particularly difficult, but that they just require some preparation and patience. This is where the "P" Rule comes in. I'm going to post the entire 12 "P" Rule, but if you're doing this for yourself, you can go with the 6 "P" Rule. (i.e. the first 6 only)

Prior
Planning
Prevents
Pitifully
Poor
Performance
Provided
Poorly
Paid
People
Perform
Perfectly

Or, as my father likes to say, "Plan your work and work your plan."

OK, here's the thing : you are going to spend at least 80 hours building a small strip canoe and more than likely, somewhere near double that if you are detail oriented and want to build a special boat. If you're going to build a boat, you want the results to be great. Not good, great. Some of the the things that you want to look great require planning.

• What will your feature strip look like?
• How will the feature strip blend/contrast with the rest of the canoe?
• Will you sort your strips for color and/or grain pattern?
• What other woods do I want to use for deck, stems, seats, thwarts and gunnels?
• Will I use unique hardware? (Canoe Jewelry)
• What shapes will I use for decks and thwarts?
• What type of seat will I have?

This really extends to a myriad of detail - you can be as detail oriented as you wish, or keep things simple.

Sometimes you're working with instructions in a book, a video or an article. Be prepared by thoroughly reading (or watching) and understanding all of what you have seen. If you don't, you're liable to make a mistake. It's not a big deal if you don't get what you've read the first time - go back, read it again and if you still don't get it, get some knowledgeable help.

The other big planning is logistics - do you have all the material that you need to begin the job you've set out for yourself on any given day? If you don't plan well, you'll find you fritter away all of your building building time running down to the hardware store or the lumber yard. This is one of the reasons you can turn an 80 hour job into a 160 hour job, too...

Planning ahead is particularly important for safety, too. Before you rush over to a power tool and try to just "trim a bit", think about how you are going to do the work. Use a piece of scrap to test your set-up before cutting your expensive mahogany that you were just looking for.

It's all part of the plan, man.

Last but not least, you should have a chair in your shop - hopefully a comfortable one where you can sit, think, read and plan. I've often heard them referred to as "moaning chairs" where you sit and think through the problem you've just created for yourself, rather than continuing to try to work and making the problem worse.

Somehow, this concept doesn't appeal to me even though my chair sometimes gets used in this way. I prefer to think of it in another way - as a sanctuary to relax and prepare or as Greg Rössel says, "a place to think and to take restorative beverages."