Chapters1-3: Introduction

Setting Up

(Our First and Second, Plans-Built Projects!)

Aviation Products' GeeBee R2 (http://showcase.netins.net/web/pedalplane/)

The GeeBee R2 Pedal Plane belongs to Jackie, our 4 year-old daughter, who also has an addiction to airplanes (she named it JayJay, after the cartoon jet-plane of the same name.)  I built this pedal-plane in the winter of 2000; trying to finish it in time for Jackie's 3 year birthday party that March.  I ended up being a month late, mostly due to changing the plans for the nose cowl.  I didn't like the built-up pine former method in the plans because I thought I would never get the shape right; I built it from fiberglass instead and I spent a LOT of time fabricating a Nose Cowl Mold out of plaster. The result was a pretty nice nose cowl (it is probably the most perfect piece on the plane), but it cost me almost as much time to build as the whole of the rest of the plane combined (and the material cost was higher as well!)

There is a lesson in all of this.  To deviate from the plans may or may not give you a better part and it will most likely cost you more time, more money, or both.  I am not saying that a builder should never deviate, but he should be very, very cautious when he does!

Having said that, I know there will be a few places where I will end up deviating from the plans for the Cozy MKIV (mostly based on the experiences of others who have gone before me.)  I intend to restrict these deviations as much as possible and to apply common sense to any modification I may consider.

In my limited opinion, modifications come in three categories:

1. Modifications discussed and or approved by Cozy Development Corporation (low risk).
2. Modifications that others have done before me but are not approved by Cozy Development Corporation (medium to high risk).
3. New Modifications that I may come up with (VERY high risk!)

Of course common sense also applies here; moving the Headset Jack from the arm rest to the instrument panel is not in the same category of risk as installing an untested, unproven engine.  Any modifications I may apply, I will detail on this web-site and let other builders know of my results.

The Cozy MKIV Plans, Chapters 1-3

September, 2001

The first three Chapters of the plans cover the Introduction, the Bill Of Materials, and the Education it requires to build a plane like the Cozy MKIV.  I'm not going to repeat what is covered in these chapters; except to explain how I have set things up, and the problems that I've run into.

Because I live in a state that is climatically opposed to epoxy lay-ups for at least 6 months of the year (northern Illinois), I have had a bit of work to do to get an acceptable (read Insulated and Heated) workspace set up.  

The chosen work area was the Garage, but I had quite a lot of work to do to get ready for building; like building a shed for all the lawn equipment and kids toys; selling our Corvette (Barbara told me that I'd have enough space in the garage to build a plane IF I sold the 'Vette...women are so cunning, aren't they?), and setting up The Shop.

At least it is a two car garage!  (I have read some of the horror stories on the Web about fitting a Cozy through a single car garage door.)

Shop Setup

The plans call for building an epoxy balance (Don't do it!  Get a pump instead!), building a 12'x3' table, and various other bits.  I'm waiting on building the 12'x3' table as I already have a 4'x3' and a 3'x3' table in the garage and I'm presently limited a little on space as I have the Chapter's Link Sim in one bay.  The table won't be necessary until Chapter 5, when I build the Longerons and Fuselage Sides.

The Epoxy Box

A hot box for the Epoxy Pump is essential (especially for Northern Illinois!), so I built one out of 1/4" plywood and bolted it to a rolling cabinet (that way I can move it around when I am doing large layups.)

I also added a 100W Light Bulb and a Line-Voltage Thermostat (available at Menards).  I originally planned to use a household thermostat that I had spare, but it was rated for only 24V and hence would need a transformer and relay, which cost more than the $13 I spent on the Line-Voltage Thermostat.  The other advantage of the Line-Voltage thermostat is that it can be mounted in any position since it is based on bi-metallic springs rather than mercury switches.  The temperature is stabilized between 105F and 114F using this setup (with the light bulb turning on approximately 50% of the time.)

The 'Glass Box

I got this idea from a fellow Chapter-790 builder (Dean May) who is building a Velocity.  The 'Glass Box is 4'x4'x8" and is bolted to the wall with the 'Glass rolls hung inside the box on 1" dowels.  The table is hinged at the back (to the 'Glass Box) and the legs are hinged to the bottom of the table.  The table then lifts up and becomes the door when I want to close up the box and seal it (the legs, being hinged, fold flat against the table/door when closed.)  This approach has a couple of advantages in that the table becomes a cutting surface when cutting cloth and when closed up it seals and protects the cloth from contamination when I'm doing 'dirty' things like sanding foam, cutting cured 'glass with the bandsaw, et cetera.  Currently, the 'Glass Box is not heated, (no epoxy is stored there), and I believe that the 'glass loses its heat rapidly once out of the box...negating and benefit of preheating.

The Practice Pieces

I know that many builders have gone straight into building the Bulkheads and have had good results, but being an Engineer (and a rather pedantic one at that!) I felt that I should at least do the practice pieces that involved foam (a type of construction with Fiberglass that I haven't done before).  As it turns out, this was a good decision (see 'Problems' below).

The 'Confidence Builder'

The intent of this Practice Piece is to familiarize the builder with Foam/Glass construction and to demonstrate the strength of composite materials.

My 'Confidence Builder' came out fine. During the layup, although the plans don't call for it, I added some dry micro to the radius around the base of the foam to keep air bubbles out.  This worked reasonably well, but there were a couple of small (less than 1/8") bubbles that formed on the sides.  This meets the criteria for an acceptable part, but I'm not entirely happy (I want NO bubbles!)

The Bookend/Picture Frame

The purpose of the 'Bookend/Picture Frame' practice piece is to introduce the builder to layups with complex/compound shapes, using Dry Micro to radius inside corners so the glass fibers will lay in the radius, and using Flox to make a re-enforced corner.

The above pictures show examples of the inside corner (practicing with Dry Micro) and Foam Carving.

The picture on the left shows the base layup (with Flox Corner at the front), and the picture on the right shows the finished product.  I used John Slade's tip of 4mil plastic peel ply (although in hind-sight I should have made a little flat plate to weigh on top of the peel ply to get an optically flat surface.)

Problems, Problems, Problems...

Microing Radiused corners seems to be one of my biggest skill gaps.  If you get the micro too dry it is very difficult to spread and radius into the corner; too wet and it deforms and runs under stippling and then air gets into the layup (due to a too sharp radius for the glass fibers to now lay into.)

The above pictures show the problems.  In the two pictures on the left, the micro was too wet and deformed or ran under stippling.  In the far left picture, the micro ran completely out, in the middle picture, it deformed and let air in.  The far right picture is an example of a correctly microed corner.

Fortunately, I didn't have any problems with the flox corner.

What I have learned so far...

If you are new to Fiberglass/Foam construction, take the time to do the practice pieces; it will highlight any skill gaps you may have and give you an chance to fix it before it really counts