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Monthly Archives: May 2012

Brian (left) sits back and enjoys his first ride in the newly completed Bolger designed dory while Bob (also one of the course students) rows.

Launch Day Finally Arrives

by David Skelhon

Five months has passed since we first started cutting plywood for the Bolger designed Gloucester Light Dory. As you might recall, much of the initial construction was done by five eager novices on the “Beginning Boat Building Course”. The half-built dory was then purchased by Brian and Carol Elliott back in March and finished by Brian.

I am delighted to report we finally launched her at the Cowichan Bay Maritime Centre on a fine but breezy spring morning and I managed to take her for a quick sea trial. She rows just as I hoped! She is easily driven, has enough skeg for directional stability, and during the brief workout seemed well mannered. A little “tender” for sure, but she was lightly loaded at the time. Weighed down for an expedition I’ve no doubt she would feel rock solid.

Knowing the Elliotts,  I’m suret they will use her to her full potential and I’ll keep you posted.

A dory of this type looks very simple to build and and the techniques involved transfer readily to bigger, more complex designs. Here are a few general tips and recommendations that new builders should take to heart.

 Measure Twice, Cut Once!

It’s been said many times before but it’s worth repeating again. Measure twice and cut once! Well, actually, if you are cutting a complex, 3D component then you are likely to be doing a lot more cutting and fitting than that. Skill and experience are important and there are few tricks and devices to speed things up, but when you are learning the basics it will be tedious and you will screw up from time to time. This boat may look simple but if you have never before fitted, for instance, a thwart, with its beveled and curved ends, you may find yourself scratching your head! Be patient, find a piece of scrap or cardboard to build a pattern first before you cut into that expensive piece of mahogany!

 Getting to Grips With Glues

If you are new to epoxy, read the instructions carefully before you start. With West System, for example, remember to use one pump of resin to one pump of hardener. The mix may be 5:1 for 105 Resin with 205 or 206 hardener, but the pumps are calibrated to deliver that ratio with one pump of each. 207 hardener, which is recommended when a bright finish is needed, has a 3:1 mix. Make sure you are using the correct pump for that hardener!

This may seem obvious but we did at one point have a sticky mess on the boat which was never, ever going to cure  because one pump of hardener had been added to five pumps of resin!

West System’s technical department had obviously heard this many times before and advised using a scraper to remove as much resin as we could and then washing the remainder off with acetone before applying fresh resin.

Please, please remember that uncured epoxy is toxic. I personally know half-a-dozen builders who have become sensitised to epoxy – so much so that they cannot walk into a building where there is uncured resin without experiencing a severe reaction. It is important to add that these users failed to protect themselves adequately, often working for months or years without basic skin protection.

Remember that there are alternatives to epoxy. We used Gorilla glue on most tight fitting joints and it worked like a charm. It’s so easy to use; there is no mixing and measuring, – just squirt it out of the bottle and spread it. Clean up couldn’t be easier, because excess glue foams and can be shaved off with a chisel or knife. It’s cheap compared with epoxy especially when bought in a large bottle. We used it in scarfs, butt straps, frames and the laminated stem and stern. We didn’t use it on the gunwale or chine logs because it was easy to work with slow curing epoxy when accurately clamping long pieces of lumber onto curved surfaces. We also used green painter’s tape on many epoxied joints, pulling it before the epoxy cured, avoiding a lot of difficult sanding later.

Finally, when protecting epoxy with varnish or paint, make sure the epoxy has had chance to fully cure and that any amine “blush” is removed from the surface (a little dilute ammonia solution does this quite well) and then lightly sand the surface. Failing to remove the waxy amine reaction by-product can result in paint or varnish drying very slowly or not at all.

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