This page shows how I cut and fiberglassed the Starfire body tubes.

First thing for getting started is to cut the body tubes to the proper length.  I do this by marking the tube in a couple of locations around it and then installing a hose clamp band to act as a saw guide.  Low tech, but works great!  A hacksaw with an appropriate blade can be used by holding it up against the steel band.  A little patience is all that is required for an accurate cut.  Just work your way around the tube gradually making the cut a little deeper as you go. 

The tubing shown here is "flexible phenolic" but this scheme works great on all types of tubing. It really helps ensure the end is cut square with respect to the axis of the tube.

You can find these neat little pipe holders (called saw horse bucks) at places that sell saw horses.  They work great for holding body tubes.  My sanding station is next to a window in an unfinished part of my basement.  A box fan is used to pull the sanding dust away from me and away from the rest of the basement. The dust is simply exhausted out into the window well.

Once the tubing has been sanded, it is placed onto the "rocket rotisserie".  This setup is not required, but makes it very convenient for applying the epoxy and fiberglass.  I use two saw horses with the pipe holder fixtures on them.  A length of 2" PVC pipe is run through the middle of the body tube and laid between the two saw horses. The body tubing is centered on the PVC pipe using a large piece of foam cut to roughly the right diameter.  Making the foam piece a little larger adds to the holding force.  The center of the foam piece is drilled slightly smaller than the PVC pipe and then the pipe is just forced through it.   The body tube is held with enough force that it won't easily spin on the PVC pipe.  This allows me to pull lightly on the fiberglass as it is being rolled on in order to prevent wrinkles.

Another view of the saw horse and the saw bucks that hold the PVC pipe.  The PVC pipe goes through a piece of pink foam inside the body tube.

The blue tape on the concrete floor is to hold some plastic sheeting in place to catch the inevitable dips.

Here is a side view of the pulley motor fixture.  The pulleys are mounted on 1/2" steel rods that go through some pieces of oak wood.  There are no ball bearings here.  Just a little graphite dust on the shafts and the oak.  The idea here was to get a large reduction in shaft rotation rate from the electric motor to the body tube.  There are three stages that each use a small pulley wheel turning a much larger pulley wheel.  In the end, the body tube will rotate about once every five seconds.

This is a view of a piece of pink foam used to hold the tubing in place.   It is 3" thick foam that was marked for the proper diameter by just tracing around the outside of the body tube with a magic marker.  The foam was cut slightly larger than the mark to allow for some compressive holding force on the tube.  The center was drilled with a 1.5" diameter hole saw. 

To fiberglass the body tubes I use 6 oz plain weave glass.  This is a roll of G7628 that I purchased from CST.  They offer it in 50" widths which is perfect for 48" long sections of body tube.   I used three layers on some of the body tubes and two layers on the booster section body tube.

The fiberglass needs to be cut to the appropriate length.  I then sealed the end of it with a spray adhesive.  This photo shows a small 1/4" section of the fiberglass exposed between two layers of newspaper.  A very light spray coat of adhesive keeps the ends from fraying.

I only seal one end of the fiberglass.  The end that is put onto the tube last.  The end that goes down first does not usually suffer much stress that causes fraying.  The end that goes down last is typically handled a lot more and can tend to fray a lot.

Smaller rollers are also available for use on smaller diameter body tubes.  However, it is not very critical what size is used. 

Besides the foam roller, it is often convenient to also have some small foam brushes handy.  All these items are readily available at paint stores.

Gloves are a necessity.   I use these vinyl gloves available at Home Depot.

To begin the process I always mark a straight line on the body tube for initial alignment of the fiberglass cloth with the axis of the tube.  I found that if I skip this and just do it by eye, then by the time two or three wraps are put down, it is invariably crooked and runs into problems covering the ends of the tube. I shoot for about one inch of overhang off each end.  This is trimmed away once the epoxy has cured.

The whole length of fiberglass that I plan to use is wrapped around another length of PVC pipe that is placed below the body tube and supported on each end by the same saw horses.  This makes it convenient to pull the fiberglass and roll it smoothly onto the body tube.

The pumps that are available for West System cans are well worth the minor cost.  This epoxy needs to be mixed in a 5:1 ratio, so the pumps make that easy.  One stroke of each and you're good to go.  Or in the case of Starfire, 5 pumps of each!

I use the pumps to dispense the epoxy into a 12 ounce plastic cup for mixing with a small wood stick.  However, don't be tempted to leave it in the cup!  It will get very hot and cure within about 10-15 minutes.  Once it is mixed, pour it into a plastic picnic plate.  This increases the surface area of the epoxy so that it will not self heat and greatly extends the working time.  The plate also makes it convenient to roll the epoxy onto the foam roller.

Now it is just a matter of rolling a generous amount of epoxy onto the bare body tube.  I found that after a little experience, it is possible to apply the right amount of epoxy right from the start and then roll-on two or three layers of fiberglass all in one go.

The tube is coated and we are ready to align the fiberglass with the pencil mark and begin rolling it on.  By the way, this operation is done without the motor!  Take it slow and work out the wrinkles as you go.

The fiberglass should be rolled down firmly in contact with the tube using the same foam roller.  This works really well for eliminating any wrinkles or bubbles. The fiberglass changes to a transparent state once it is saturated with epoxy.

As we near the end, the fiberglass has come loose from the supply reel.  Still about one wrap left to go.

Almost done!

And now I have reached the end of the fiberglass that I sealed with the spray-on adhesive.  This seam can be firmly laid down with the roller without any trouble from fraying ends of glass. 

For truly high performance tubing, some people will wrap the tube in a constricting tape that squeezes out excess epoxy.  They may even put the tube into a curing oven to reach maximum strength on the epoxy.  I did not find that necessary for Starfire. 

Once the epoxy has fully cured, it is time to return to the sanding station and sand down the seam as well as any other defects in the surface.

For repairing minor cosmetic defects, I used this two part filler called "Icing" from my local auto body paint store.  It is a nice creamy mixture very much like cake frosting that can be spread over and into the defects and then sanded smooth.  A very small dab of harder is all that is needed.  This stuff will cure in about 20 minutes.

The seam joint on the body tube has been coated with icing and is ready for final sanding.  Did I mention I hate sanding!

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