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[ballastanksian]

I reckon the quality of density is because the steam doesn't have to travel very far at all, so less steam has condensed in the system, the heating system need not have so much redundancy because it isn't catering for distance, and each system is feeding its self only, so is more efficient.

It is still amazing, and if elements could be 3D printed then it would be a splendid product especially allied with the turret control system that fellow Mayhemists are experimenting with 

We need a few of the kaiser's fleet to add some smoke to the skies.

[Geoff]

Whilst the fog fluid is made up of de-mineralised water, glycerine and a certain type of glycol I don't think we are seeing steam. I believe that the water flash vaporises which in turn atomises the glycerine and glycol forming tiny droplets which in turn refract the light giving us the fog, so the water is the "flashing" medium and the glycerine/glycol form the small droplets which give us the "smoke". Otherwise just pure water would work and it doesn't - tried it!

Cheers

Geoff

[Geoff]

I meant to add, that the purpose of the alloy block is to store the heat energy so it can flash vaporise the fog fluid. Fundamentally it takes "x" amount of energy to change a liquid to a gaseous state in "y" amount of time. So all the stored energy can "dump" into the fluid and the rate of heat transfer is governed by both the alloy mass and the maximum amount of energy it can store and the surface are of the central hole to transfer the heat which in turn builds up the pressure so its ejected down the length of the barrel.

I suspect there is probably an optimum relationship between everything but I just don't have the sophisticated measuring equipment to analyse further. I also suspect at the small scale we are working at that there would only be minor differences anyway.

Cheers

Geoff

[ballastanksian]

Yes, sorry Geoff, that is what I meant to say in my post 22:00 way! I think looking at the images, you have probably have the constituent parts pretty well balanced.

[Geoff]

After about 5,500 shots I was checking the guns and realised that the plastic barrels have distorted with the heat at the muzzle end which is somewhat annoying.


I know we strive for realism in our models but the god of models is taking it a bit far when I have to change barrels every year or so but I guess I shouldn't be surprised as its really over 1,000 shots per working barrel! Just like the real thing after extensive firing the barrels need replacing!


I'll try to replace them with a metal version so I won't have to replace them again. I also found that X and Y turrets the insulation was soaking. I can't see any evidence of a leak so it may be the filling tube was passing fluid - I'll monitor the situation.


Cheers


Geoff

[Geoff]

When I was at Wickteed Park over the weekend a gentleman kindly took a video of Iron Duke per the attached link.


Thank you


Geoff



 HMS Iron Duke 1/96 scale, over 6ft long with working turrets





RC HMS Iron Duke escorted by 2 destroyers (1/96 scale)

[Bob K]

Really great videos Geoff.  I posted the first one on my Facebook.   

[ballastanksian]

Both your escorts belong to Tony who is a fellow Mayhemer. In the mosaic of videos shown at the end of the latter video, I saw his escort fleet shown in another of RC Model Warship's videos of the Warwick show.


The children's enthusiasm was lovely to hear and shows that traditional models with some technological marvels still capture their imagination 

[danl]

Geoff,
Great videos...and great firing effect.  Congrats on developing such a great approach to firing guns.
I finally ordered some PTC's to build some prototype carronades for my brig.  Will keep you posted on progress.
Thank you for writing up all the details of your work.  Much appreciated.

[Geoff]

By way of an update I was having some reliability issues with the gunnery system - mostly servo issues and link failures so I decided to completely strip one unit down to see what was going on. To summarise:


1) The PTC Thermisters continue to work perfectly - no issues


2) 4 out of 5 gun barrels have distorted near the muzzle and need replacing. In checking this out I found the barrel insulation soaking for its full length - the "O" ring seal at the muzzle end was not holding up well so this would wet the insulation creating significant heat transfer to the barrels and a drop of in performance and distortion. I have now used a high temperature silicon gasket sealant from Halfords - max temp 350 centigrade and of course more flexible.


3) I removed the end plug on the heat exchanger and found some internal discolouring (black) but no debris of furring up at all so they are working very well. Its worth mentioning that each "gun" has now fired over 1,000 shots so very pleased no internal problems evident. I replaced the end plug with a "L" shaped fitting to preclude any silicon pipe kinking - just a suspicion as the angle was very acute.


4) The servo operated at the top of a relatively long lever. I have now introduced a lever pivoted at the center so the "pull" is now much lower down and more linear to the pump piston. This should reduce strain on the servos and give a better pull.


5) I also found that the center hole in the base of the turret had got wet and was a tight fit so this was filed out and the turrets now fit much easier.


Overall it took about 2-3 hours per turret to remove, modify and refit!




Cheers


Geoff