Welcome to a work in progress

This blog is dedicated to the restoration and modification of a Glasfl├╝gel Standard Libelle H201B, and a tribute to those who have dared to do the same, and to those who are helping with seeing this dream take flight.

Wednesday, January 25, 2012

Making new GRP Holders and Straps

Pass me a bottle... please!
Now that all of the gelcoat has been stripped off of the glider, my focus has been to get the interior of the cockpit finish, so we don't damage the outside before we are ready to prep it for painting.

For those who are just joining in, over a year ago, when I started this project, I found an old thermos bottle rolling around in the fuselage.

Being new at this, I was unfamiliar with use of a capacity flask, and back in the day, thermos bottles were used as one.

Several months later, I purchased a new Winter Vario to replace the thirty-plus year old one. The new Vario came with a new light weight .9 liter flask.

I'm now working on creating those fiddlie bits to secure parts in place.

I had a discussion with Robert on how some components are secured in the glider, in this case, mounting this flask, and where.
He stated, you will need to make a cradle out of fiberglass for the flask. As for the location of the bottle, it is recommended that the placement of the bottle needs to be equidistant from the TE probe to the Vario. This placement is close to where the old Thermos was located.

And here is where the old Thermos was glued. It was against the outside of the wheel well and resting on the right side of the belly.

Another area that will need to be cleaned up before I can move on.

To start with making the Capacity flask holder, I needed to make a mold of the flask ends so I could create a cup to keep the flask from sliding back and forth in the holder.

Using the flask as a male form, I molded aluminum foil around the end. I smoothed the foil out the best i could do to create a female mold. I then pored urethane resin into the temporary mold. After the resin hardened, I removed the foil. After repeated coats of filler, I had a smooth finish. I used a polyurethane paint to finish the surface.

The last step was to lay over a couple of plys of 7725 glass with epoxy resin to create the cups.

To create the cradle, I wrapped a piece of plastic around the flask to create a tube shape.

I then layed a couple of plys of fiberglass to create a half-tube.
After the resin cured, I cut two pieces to the length needed for the cradle.

I cleaned up the end caps with the cradle parts, and test mated the parts to ensure that they were even.

I needed to replace some of the original GRP straps used as tubing and wire restraints, and this shape can also be used make a stand-off for the bottle cradle.

I made a mold for the bottle stand and straps using a piece of hard wood, seal and waxed it well to keep the resin from sticking to it.

I applied three layers of 6 ounce fiberglass .

After the resin cured, the sheet form popped off without any problems.

The finished stand-off rail sheet.

I trimmed away the excess glass on the sides, leaving a lip on the stand-off for the flask cradle to rest on, and an adhesion area for the epoxy resin.

I tested the shape of the flask cradle to make sure that the form was level, and then did a final trimming before applying the epoxy resin cement.


The end caps were cemented to the cradle form with a light amount of epoxy resin.

When the epoxy cured. I carefully cleaned of the shape by sanding the off the excess resin, and then evened the sides of the shape.

A reinforcement fiberglass strip was added to the both the inside outside of the flask holder ends.

After the strips had cured, I trimmed off the excess.

And lastly, the trimmed standoff was epoxied into place and a strip of 6 oz glass was applied to the sides to reinforce the shape.

In the bottom of the cradles stand-offs, I cut openings for plastic zip-ties to secure the flask when it is installed in the fuselage.

The flask holders where finally cemented in fuselage. Additional strips of fiberglass, wetted with resin, secured the stand-offs on the clean fuselage skin.

How the finished flask holder looks in the belly.

The next task is to replace the old lost and dried out straps for the hoses and wiring.
I needed to replace four straps, three in the nose, and one in the side.

Using the same mold, I created a sheet glass of the pre-shaped form for the replacement straps


New straps were cut to the same size as the original, and using a thickened epoxy, I glued the straps in while having the fuselage rotated upside-down.

Masking tape held the straps in place while the resin cured.

The tape was removed and any excess resin was sanded off and the straps smoothed to hold the pitot hose.

The side strap for the wiring was secured using the same technique as straps in the nose.

I sanded and painted the area around the strap.

For the water dump system, there is a Teleflex cable used to active the valve. I created a GRP strap to hold the cable in place. To create the straps, I used a wood dowl rod that was the same diameter of the cable. I cemented the rod to a board, and filled the sides to level it to perpendicular to the board.

I used two plys of fine fiberglass bonded with epoxy resin.

I added peel ply to smooth the surface.

After the resin cured, I removed the sheet and trimmed away one side.

I cut several tabs to be cemented in the cockpit side.

Following the drawings for the water dump system used to convert the H201 the 201B, a resin paste was used to attached a few of the tabs which will be used to secure the Teleflex cable.

After the resin cured, I cleaned up the tabs and slightly painted the area with primer.

The cable I have is a throttle cable, and not an official Telefex cable. I could not find a cable the correct length. My glider did not have a cable. So, this find was perfect, the only problem was, there was no way to mount it to the rear cockpit bulkhead. I made a mount that will be used as stand-off for the end which is used to attach it to the valve lever.

The stand-off was made of a mix of epoxy resin and flocking. A stainless steel bolt molded into the form.

I sanded a grove in the top of the stand-off for the cable ferrel to rest in.

I will use resin and fiberglass strips to secure the cable to the stand-off. I will install the valve actuation cable after I receive the proper water ballast system kit from Streifeneder.

Time to do the final sanding in the cockpit before painting.

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