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[SteamboatPhil]

Looking really good Dave and a nice installation 

[DBS88]

At the beginning I said I would tell you what didn't go so well - so here's the beginning of a frustrating saga that will take a few posts to complete. - When I fired the boiler and brought it up to pressure the engines ran well. When I set the gas attenuator I did notice that with the engines running the attenuator was not responding as I expected so I decided to change the pipework so that the attuator was more direct to the boiler and that the engines were not on the same outlet from the boiler. I also confess that a couple of the silver soldered joints also leaked. I then reassembled the steam plant with the new pipework for the attenuator and the re soldered pipes to the steam dryer. Heres the revised pipework

[DBS88]

Frustrating time spent in the workshop is still better than a good day at work. I spent considerable time burning my fingers and doubting my engineering abilties. I had changed the piping for the steam supply to the gas attenuator, and used a four way fitting in the boiler outlet for the pressure gauge and the steam pipe for the attenuator, leaving one spare outlet. When I fired up the boiler, I noticed two issues, the first was a leak that appeared to come from the washers above and below pressure guage banjo fitting. The second was the presuure guage was not rising, initially I thought this was because of the steam leak. As I disassembled the pressure guage fitting I found the banjo was locked to the bolt, the bolt would not rotate without hte banjo as a result the pipe to the guage snapped off. Next I found the banjo was blocked with sealant, obviously I had used too much locktite and the excess found its way to places it should not have.

[KNO3]

You could also use a normal cone and nut for the pressure gauge in your application. Makes things easier to build than a banjo fitting.

[DBS88]

Thank you for the suggestion of using a different fitting for the syphon. I was lucky and had a spare syphon tube and banjo fitting so installed that only to find that there was a leak around the banjo fitting. I couldnt wait for the boiler to cool so worked on it whilst hot and redid the joint with new washers, again the same problem. I remade the joint numerous times and still it leaked even with thread sealant. Then I realised that the fitting itself was leaking via a crack or blow hole. I replaced the now broken fitting and reassembled the steam pipe to the attenuator and to the pressure guage and it all worked. The last photo shows the new configuration of the pipework.

[SteamboatPhil]

Nice 

[DBS88]

For interest and science, I heated the broken fitting up so that it was glowing red hot, the solder did not run, when it was cold I tried filing the solder, it, it was very hard, I therefore believe the fitting was silver soldered. All the pipework joints that I have soldered have also been silver soldered.
I test ran the boiler and when it was up and running, and making good steam, the engines ran nicely. Then I encountered the third problem of the weekend, the sound from the burner changed from a gentle sound to a louder roar. It was a sound I recognised from another incident on my boat Formidable. I turned off the gas and disassemebled the pipe to the burner. With the burner on the bench, it was clear to see the cracks in the ceramic insert, a test burn confirmed an unstable flame and the roaring noise as the burner destroyed itself.

[DBS88]

Fortunately I had some ceramic board left over from repairing the burner to my Hemmens model of Formidable. The burner for Perserverance is a MacSteam burner that came with the MacSteam boiler, I belive the boiler maker used had good quality materials and that the ceramic cracked maybe due to age? The cracked ceramic was removed and a new ceramic insert was cut using a hole saw. The insert was then sealed into position and left overnight to cure. When tested the burner performed well with a nice blue flame. A second test was done using the pipework installed for the boat with the burner horizontal.
I read that some ceramic boards can melt so I checked the replacement ceramic matt that I use to repair burners, I used my blow torch with MAPP Gas, which burns hotter than the propane butane mix, here is a photo - the replacement ceramic matt does not melt.

[Martin (Admin)]

    Impress burner!   

[DocMartin]

Beautiful work.  It is a joy to watch the progress.
What do you use to seal the ceramic board?

[DBS88]

The ceramic material was sealed into the burner head using fire cement that came in a tube. The old burner cracking was worrying me. Having thought about what was happening prior to its failure, the leaking steam fitting was above the burner and water did drip onto the burner whilst it was alight, maybe the thermal shock was enough to damage the ceramic. Also concerning was the thought that the material used might not have been good. So with those thoughts in mind I tested some of the broken pieces from the original ceramic burner. I palced the pieces on a heat resistant matt and used my MAPP Gas blow torch. The pieces of ceramic glowed and the heat matt got so hot it melted! The ceramic remained intact and did not melt so good news there was nothing wrong with the ceramic and the probable cause of the failure was water getting onto the hot ceramic. First photo is a small section of the old burner glowing. the second photo is the same section of burner after it had cooled, as you can see its structure has not melted or deformed.

[DBS88]

Here is a link to a video of the steam plant running after the repairs. The plant runs well and will be adjusted after a few more test runs to allow the engines to bed themselves in after they have been reassembled.


https://youtu.be/-rXseq8Mt1A?si=orjdvQ5F08rb5wsA

[DBS88]

I was given an airbrush for my birthday and wanted to learn how to use one. Previously all I have painted with an airbrush is a small Airfix Spitfire that I did at Christmas. The Perseverance kit came with some moulded resin/fibreglass cabins, these were my chance to get the airbrush out and practice some painting techniques, the first one I wanted to experiment with is pre shading, to enhance the joints and rivets on the cabins and to try and create some light and shade rather than a flat uniform colour, to try and make the cabin more interesting visually and hopefully more realistic? This is cabin as moulded, with a bit of rubbing down, some filler, then the presiding and next a first coat of white primer. I am just having a go at this after watching a few videos, so I could be doing this all wrong, but I am learning as I go.

[DBS88]

The colours to paint this model were researched and here are some photos of Royal Navy Dockyard Tugs and the colours used, these then inspired my choice.
After pre shading and priming I applied the finished colour. The research revealed a colour scheme for Royal Navy Dockyard Tugs, that the upper structures were Buff and the metal decking should be Olive Green. After a couple of coats of Buff it was apparent that my filling and preparation work were not good enough, so I rubbed down some more, applied a different filler, Mr Surfacer 500, and rubbed down again. I then touched in the newly filled areas with a brush – it looked a mess. Then applied two more coats of Buff with my airbrush. The desired result is something that looks a bit weathered, is realistic and visually more interesting that a solid flat colour. Whether I have succeeded will be a matter of opinion – should I have applied another coat of buff? do the plate joints and rivets standout too much?

[DBS88]

The funnel needed to be painted and research suggested that it should be buff, with the top black and with a blue band separated from the black top by a buff band. The whole of the funnel was primed light grey and then shaded in the rivets and panel edges to give some contrast. The funnel was sprayed with several coats of buff until I was happy with the colour and the shading. Then with masking tape I covered the buff above and below where the blue band was going. The blue paint was unbranded cheap airbrush paint which I brushed on, it took quite a few coats to build the depth of colour, so to speed things along I used a hair drier to dry the acrylic paint. With the blue done and dry, the bottom edge of the black was masked to achieve a nice crisp line and the airbrush was used to spray the top of the funnel with matt black.
Now here are the mistakes made.
1) For the Blue, the paint crept or was driven under the masking tape by the hair dryer in a few places, very disappointing.
2) When spraying the top of the funnel there was a band of masking tape that I thought would be sufficiently wide to prevent overspray going onto the buff areas of the funnel – wrong, very wrong.
3) When the masking tape was removed, the masked buff area of the funnel was a different colour buff than the area below the masking tape, not only due to the black overspray, but it would appear that the masking tape glue and hot air from the hair dryer may also have affected the colour.
It looked a mess, so I walked away, took time out, to work out the best way of saving the funnel.

[DBS88]

Having walked away from the funnel, frustrated with my stupid mistake, I remembered some advice about mistakes, its not always necessary to start over again, its about using the mistake and making the most of it. Since the decision was to go for a used/weathered look and this was a coal fired steam boiler powered boat, it's likely that the original boat was soot spattered and smoke stained. So decided to spray from a distance a fine mist of black paint over the funnel to add more spotting to hopefully make the most of the mistake and disguise the problem with the overspray – the worst that could happen was that I would need to repaint the whole funnel, so I went for it. Heres the result, what I have noticed is that issues are more noticeable in the photos than they are when you see the item for real. The tricky bit is about knowing when to stop, how far to go – hopefully this is ok – if not it's easier to add more soot spotting than it is to take it off.