Chapter 03 Education

Chapter 3 is 19 pages long.   It includes a list of basic required tools, recommended tools, items used occasionally & can be borrowed.

Some tools can be made such as sanding blocks, long straight edge, epoxy balance, hot wire cutter, and jig table.

Materials are covered.   The types of fiberglass (BID & UNI), epoxy, foam.

Construction, repair and inspection methods are explained.

Water lines and Butt lines are explained.


----------------------------

The epoxy to glass ratio by weight is typically 1:1.    Wetting multiple layers of glass between layers of plastic on your work bench is often better (quicker and easier to handle) than trying to do one layer at a time.   Exceptions might be for long/hard to handle thin layers of glass.

Typically EZPoxy is used by many builders for the tanks even if they're using MGS for the rest of the structure.

Working time/pot life is greatly affected by ambient temperature.   Warm epoxy has a lower viscosity and wets better.   Warm epoxy can/will exotherm if it's heat isn't dissipated by stirring or spreading out.   Fast hardener is more prone to exotherm than slow.   Several layups (such as the winglet attachment) in the project have many layers and can easily exotherm if the temperature is high and fast hardener is used. 

In cold temps when using epoxy, avoid using heat that produces CO2.  Keep parts above the dew point. Use peel ply to avoid amine blush or amine bloom.  Use heat (lamps or electric blankets) to help provide heat.   See Gary Hunter's presentation on Epoxy.

Wetting multiple layers of glass between plastic is probably faster and easier than doing one at a time and is easier to handle.  A strip of peel ply can be added to this to help provide some additional support to keep the glass from acting like a wet noodle.  This is a photo of 5 layers of 3" x 22" BID, weighs about 2.5 .oz and uses an equal amount of epoxy in weight.  A chart is handy with resin/hardener ratios.  MGS has a green tint.  EZPoxy has an amber tint.   West systems is clear.

A belt sander made fast work of removing 3 layers of BID on the internal trailing edge of the cowl.   I'd drilled holes for cam locs to close to the trailing edge (plans say 1.25") but the V angle was to shallow for the camlocs to fit there so will move them in a quarter of an inch.   The camlocs need consistent thickness and the trailing edge needs to have a nice flat surface so just repairing each hole would have been tedious.   It took a few minutes to sand off the mistake and put new BID on for another try.