I think I've taken the tank as far as I can now, so it's time to move onto a new build. In fact, for the last few weeks I've been working on building up a Krick Victoria steam launch, which is going really well.
Here's a video of the final model in action.
If anyone else is crazy enough to try this please feel free to drop me a line. If there's one thing this project has taught me it's that the internet is full of very helpful strangers!
Although the tank worked perfectly well from a functional perspective, I wasn't happy with the way it looked. To me it felt a bit jumbled, with a mix of steam and radio components jumbled together.
So I've revised the design, with the radio gear concealed underneath a metal deck, all the steam powerplant clearly on display and the engine exposed at the back.
The only thing left to do is spray up the model. I plan on a simple black and brass finish to integrate the components. And then it's on to the next project, a steam car.
Not a steam-tank update this time. I was going to post up a new video of the tank complete with the condenser but the weather has been so bad that it's not been dry enough to get it outside to film for what feels like weeks.
I'm generally pretty DIY-handy, so for the last couple of years I've been loaning myself out to friends to fix stuff in their houses as a birthday present. Seems to be quite popular. I think this counts for about 5-year's worth of birthdays.
I've not been doing much work on the model recently, having instead been out and about enjoying the marvelous English Summer. If only.
Still, despite the crappy weather dampening my enthusiasm for most activities I have completed the mechanics to my satisfaction. The condenser does a really good job of capturing the oil in the steam exhaust, and also means the exhaust comes out at much lower pressure, with a gentle vertical cloud of steam appearing, rather than the previous jet blast scouring the ground behind the tank.
In the end I redid all the pipework to get the components in the right place. My silver soldering skills are much improved.
So now I really need to think about how the final model will look. I've never scratch-built a model, so this might take a while. Some sketches are probably in order.
Tried some different gearing on the tank this weekend, using Mecanno cogs to double the input speed to the gearbox, the idea being to make the tank twice as quick.
Sadly, there's not enough torque in the engine to make smooth turns with this arrangement, so I've decided to revert to the original 1:1 engine to gearbox ratio. No Speedy Gonzales for me, by the looks of things.
Also, I've noticed that there's quite a lot of oil in the steam exhaust, so I'm going to fit a Condenser to clean up the steam output.
I started again with the Regner powerplant, and it's much, much better. And cleaner, too. There were a fair few difficult moments, especially when I had to silver solder the pipes from the boiler to the engine. Got there in the end, though.
It runs pretty well. The boiler and gas tank are mounted on a plate above the suspension, and the radio gear is held above the gearbox. The only exception is the steering servo, which needs to be on the same level as the clutch lever.
Time for a good few trial runs and then a strip down and rebuild once I've decided what to do with the bodywork.
I got the prototype running over the weekend, using a combination of Meccano and dodgy soldering. It's clear that the current power plant isn't going to cut the mustard. The boiler and engine combo don't have enough puff.
It's not surprising as the model weighs in at 3.5 Kg. I've ordered a marine engine plant from Regner, which is much more powerful. It runs at 45 psi, rather than the 15psi of the Mamod/Wilesco combination. The Regner is a flue boiler, with firetubes running through the centre of the boiler, wheras the Mamod's not much more than a tube with flames under it. Hopefully the combination of Germanic power and Japanese precision engineering will see me right.
Still, it proved a point, now to build something with a bit of poke.
I've completed the renovation and alteration of the tank base. Changes include cutting down a couple of protruding driveshafts and cutting a slot in the base to allow the use of cogs to try different gear ratios from the engine to the gearbox.
Over the weekend I'm going to try and get a basic prototype up and running.
I bought a Wilesco D49 marine steam engine, complete with boiler and a Mamod SE3 from eBay. Over the weekend I fired them up to see how they performed and make the decision on what to fit to the tank.
The D49 boiler is very compact, but it's just not capable of providing enough steam to power the engine continually, which is disappointing. Thinking about it, I assume that's because when it's fitted in a boat for quite a lot of the time it's not going flat out.
Connecting the SE3 boiler provided much better results, with a strong flow of steam that really made the engine fly. I'll be going with the SE3 for the tank, the D49 boiler will be appearing on eBay.
I have to improve my plumbing technique, however. I soldered a pipe too close to the firebox on the SE3 boiler. The result, the solder melted due to the heat and the joint flew apart as it was under pressure. Steam and hot solder went all over the place.
I was sensible enough to be sitting a good distance from the boiler during the tests, so no harm done. If you're going to attempt something like this I suggest a good pair of safety goggles and healthy caution are things you should be using.
You can see how the work progresses in my Steam Tank flickr set. You can find it here.
