Adding Capstan Detaching Handles to Comm Towers

The Problem and Issues

Can't Achieve Strong Torque Grip

The first generation comm towers I build for the project hand in were simply layers of components, often with very little surface areas and glue resistant materials.

These fell apart very easily, any slight knock or even hard opening of the prop resulted in them falling apart.

My first upgrade was to switch to a system based around a solid 12mm thread bar shaft running the length of the transmitter comm tower and this extending into the wing box end and Dyson motor case to form a solid foundation.

This was then enhanced with foam filling the cavities and replacing the original fragile nerf gun connection parts entering the top of the Dyson motors with more solid parts.

This enabled me to be able to remove the comm towers for things like transportation and storage as well as being very strong with a solid base.

However, what was found when I took the prop out first time to a film and job fair was:

The tower shaft needed to be screwed deep into the prop body, around 27 cm.

This involves many screws in or out turns.
It also gets very tight, which means there needs to be a strong grip on the shaft and high degree of torque higher than I had in my hands it seemed.
The screw thread is sharp and digs in almost cutting into my hands painfully and I had no grip gloves at the time.
The only place I could really grip the shaft was at the top which resulting in my rubbing off kit bash parts.
This takes a long time… in the Film Job Fair this took over 40 minutes which would be completely impractical, especially in an interview when trying to impress.
Its was clear that I needed a comfortable force multiplier to substantially increase the amount of torque force to easily screw the comm towers in and out relatively quickly.
This needed to look a natural technological part of the towers.
The ideal would be to replace this with a bayonet quick release system but this was not easy to install at this time.

Generation 3 Problem Solving - Adding Capstan Tower Handles

Building Tower Handles

To grant torque force control, something more comfortable and safer to hold I came up with the idea of cross bar handles to create a capstan like control like what was used to pull up old sailing ship anchors.

I looked into wood which were prone to breaking first.

Fiberglass rods were looked at next, these were far stronger, however they could not be machined other than cut to size so no screw thread tapping.

There was also the danger that machining the rods releasing glass fibre just which is a strong irritant and very have to extract from skin and holding the handles would pressure the dust into my hands.

I chose to use thinner 6mm thread bar as this could be drilled through the main shaft, then the hold could be tapped to add an internal screw thread for the handles.

This was held in place with wing nuts.

This enabled me to:

Screw in the cross handles and hold their position in place.

As a tight fit and the same material this was solid and strong.

Adding Comfort Grip and End Nuts

Bear 6mm thread bar is not comfortable to hold as handles so like a sword hilt, I thickened the handles and coated them in rubber using multiple layers of wire shrink wrap heated with a blow torch, as many as I could fit.

On the outside I added dome wing nuts which acting as hand stoppers to stop hands sliding off the handles.

These were also decorative and added the tech vibe of the transmitters, more so when painted to bland in.

These handle could also be turned to the side to fit into boxes.

Evaluation

Even with the handles the problem is how deep the thread has to be worked down and the forces in volved which can risk the prop, more so there is the danger of breaking down through the wing boxes.

With hindsight the way to go would have been some form of deep-seated bayonet fitting that could hold but be released in seconds.
However, in the end a different solution was found and that was not to remove the transmitter towers at all. They can be unscrewed.
My solution was to make port holes in the case lid that the tower ends could be fed through negating the need to dismantle the prop.
This however still has an issue where the wobbling has dislodged the Dyson motors from the base. This is still held by the central core 12mm thread bar.