Update on repair of Crafers tower for VK5RAD

This issue (2) continues on with the current progress of the Crafers VK5RAD tower to last
Saturday 26th March. The last 2 working bees were spent scraping and cleaning the loose rust, paint flakes and other dross off the tower structure. The first weekend was on the 19th & 20th (Saturday and Sunday) got going by starting with a BBQ and coffee to prime the enthusiasm of all those who turned up, a big thank you top Roy who set it up, cooked and brewed ready for us all.

A good start to the task at hand !
The team was then let loose with what ever they had, power tools, wire brushes, sandpaper and anything else that could be used to clean the tower structure. We set up a power distribution system that had an earth leakage protector and a plastic box with a tested power distribution board in it, necessary as it had been threatening to rain, and we did not want to risk any body’s safety should it occur, plus the condition of a lot of the power tools brought along was unknown.

Power distribution and many extension cords.

We did this for two days, after which there was a few minor bits that were not completed that would be finished on the following Friday and weekend. Friday saw a few of us complete the process, so the next day - Saturday (26th) was designated as the day to do the rust conversion and perhaps begin painting if we could. Come the morning Roy again set up his coffee pot and biscuit station as we began to arrive, thanks again Roy, a great help to us all.

The work started by spraying the tower sections with a rust converter, an acid based liquid that turns the rusty surface into an iron phosphate and leaves a suitable surface to which the paint will stick well to. It was applied by using a garden sprayer as shown above and this proved to be very successful method and took very little time to complete.

This was allowed to dry, it was fortunate that the day was reasonably warm and a breeze was rapidly drying the acid wash. Before we could begin painting, the structure needed to be pressure washed to remove any excess acid that had not dried and the structure was allowed to dry again before painting began.
The “Paint”
The ‘paint’ is a two part process that requires the accurate mixing of the paint and the hardener in specially designed plastic pots that are calibrated with a lot of different ratio markings so that you can get the mix right, the mix we required was a 3:1 – i.e.: 3 parts paint to 1 part hardener. The paint was in a 10 litre plastic can and was worth an arm and a leg i.e. $500 for 10 litres, and the hardener was in 1 Litre tins. The photo below shows what took place. I can only describe the ‘paint’ as slow moving chewing gum, is very heavy, sticky beyond belief and sets fairly quickly.

It is an industrial paint that is designed for use on towers, bridges and anything designed to be in the open and has a quoted working life of at least 30+ years !
The mixing of this was a job in it’s own right, it needed to be carefully poured from the 10 litre container into the mixing bowl, then the correct amount of hardener added then stirred thoroughly before again being decanted into lots of tub, bowls, paint trays etc that the painters were using.
This was done only in 1 litre batches as required, one of the big surprises is how far a small amount would go and the quality of the coverage obtained. Because of its heavy consistency it was hard work even with a roller, but those using paint brushes found it even more difficult to handle and have probably had to resort to a chiropractor this week to get their wrists fixed !

Oh the pain ! Note the calibrated mixing bowl.

The team was then set to work on painting the tower sections and the progress was quite rapid, the photo below shows how we attacked the job, there was paint on the tower, the ground and the operators as well, I now have a pair of trousers that got paint on them and they can stand in the corner by themselves.

Of course, while this was going on, the AHARS cheer squad and support team were there to ably urge us on with the task, please note that they were probably playing pocket marbles !

The Cheer squad.

​Work progressed far better than we had anticipated, we originally estimated that we might be able to get two sections of the tower painted, but fairly quickly it turned into 3 sections and by about 3:30 the fourth and final section was starting to be painted as per below.

It wasn’t long before all sections were completed and we could stand back and see how the finished article was going to look. We originally thought that the grey of the paint might make the tower blend into the surrounds too much, a potential hazard for light aircraft and the like, but as can be seen, it is almost white and should present no hazard at all – much better than the rusty colour it was before.

All the sections ready for assembly.

So-What Now ?
​
The mounting brackets that hold the tower were very corroded and the holes were worn oval because of the different sizes of the holes and bolts that allowed the tower to move in them in storms. These have been repaired, re drilled and hot dip galvanised ready to once again hold the tower in place in a very testing environment, the wind velocities at the site are quite formidable in a storm, plus the rain and electrical discharges don’t help at all either.

A cable ladder has to be mounted to allow the large amount of cables to be fixed, plus the
terminating box for them fitted as well, so there is still a considerable amount of work still to go.

The tower needs to be re-assembled and turned over, there will be sections that will need
to be touched up that we have missed, the pad sections of the feet need to have a small section of weld between the two to make good conductivity between the four sections and make for a very electrically quiet tower that won’t generate noise and intermods.

The earthing of the tower legs needs to be completed when it is erected into place and stable again, the main antennae need to be fitted and the lightening arrestor will be installed on the top of the multi-band array.

Then comes the biggie - Getting it back up in one piece!

A piece of History

I have had a couple of photos sent to me by Colin Rieger VK5ACE that were taken when the tower crashed and damaged it. I am unsure of the date, it is suggested that it was in the 90’s, buit they graphically show what the tower used to look like before and after the event, plus a couple of chaps that you may recognise (or not).

and finally,

Do you recognise those below ?
​
from the left is Dave Mincham, Adrian Snell, and Mark Spooner

Obviously taken in the days when we all had hair !!!

My thanks must go to all of those people that have rallied to the call and made themselves available to help out in this project, there is still some distance to go, but at least we can see the light at the end of the tunnel now, I just hope it’s not a train coming the other way !

de Barry, VK5BW
​
28/5/18