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[andywright]

Christmas present now built!

[andywright]

The question is now, will the gas tank benefit from being fitted for'd of ther boiler, will it absorb a little radiated heat from the boiler to help stop any cooling pressure drops




or here amidships where there is a shorter run of gas pipe



I am not struggling on displacement so it can go for'd if it would benefit the gas supply.

[Underpressure]

Lots of views on this subject, but if it were me, I would mount it in front of the boiler and arrange some sort of heat transfer device that is in direct contact with both the boiler and the gas tank; something like a bit of copper sheet suitably shaped.

It's all looking very nice and that engine is a gem.

Neil

[mogogear]

Nie job and nice looking boat as well...

Just a question Andy- any reason why you have the burner back near the engine  as opposed reversed with it afore the boiler?

[kiwimodeller]

I was just thinking the same, that the boat might look more balanced with the funnel back closer to the engine, the gas tank would then be right next to the burner (if you put it forward) and although the steam line to the engine would be longer it would be easy to run it in to the funnel to have a superheater loop which there has been lots of discussion about lately. Cheers, Ian.

[andywright]

Mogogear, Kiwimodeller,
Well that put the cat amongst the pigeons so to speak,


or






I knew as soon as I drilled holes and fixed something another idea would crop up.
I guess it was just convention, being a full size boat person ,have all the controls visible from the conning position. But it isnt a scale model of any particular full size boat, I built this model to do a bit of pretty woodwork, and dabble in steam, so improving efficieny has to be a plus.

Did wonder about fixing the steam line through the funnel to 'super heat/ dry' the steam, turning the boiler around does make this easier, I hadn't had a look at the profile since making the boiler mounting plate, but yes it does look better, I can slacken the pressure gauge and turn it around to face aft if required. I think  will go down this route, the boiler can be fitted another inch or so forward to make more space aft, but it does look OK now. I intend to fit either a canopy or aft cabin, so with the funnel aft it will probably look better again. Her in doors says it looks better as well.
Thanks chaps, more to follow.

[mogogear]

Is the steam supply globe valve and S/V  able to be interchanged? That would have your supply line right at the stack and easy as pie to run through the stack a "drier" although not true super heater.. It will help..She sure is a clean lined boat!

[andywright]

It is probably easier to run the steam into the smoke stack from the side, the S/V is close to the stack and it would be awkward getting the fittings in place.

Andy

[andywright]

Well got the TRV1A running and fitted, had to revamp the layout abit so here is the progress todate, the starboard for'd bench seat has been shortened, to make room for the gas tank, still deciding whether to even things up and shorten the port side as well.
Have turned the boiler around so the funnel is more amidships, as previously sugested, this has balanced the boat up nicely, and made the blow off valve easier to get at. Have not run the steam pipe through the stack yet, got to decide on that one, Graham industries recomend not superheating, I know just a pipe through may not exactly superheat, so may improve this later. Will see how it goes for now.
Have bought some 2 1/2inch pipe to fabricate a condenser/oil separator out of, that will go on the port side.

[gondolier88]

Hi Andy,

That's looking fantastic mate!

I would imagine that GI advise not to superheat because of the abundance of aluminium in it's design- however a single pass through will help marginally with condensate issues, and will not heat more than a few degrees above boiler temperature.

Greg

[andywright]

I did think of it, as the steam feed is further away I thought it may replace the small heat loss with the pipe being longer. Fitting the steam control valve would be a bit more difficult. The pipes still need to lagged, but I am waiting for some nipples to complete the soldering. I have bought some 2 1/2 inch copper pipe to fabicate a condenser/oil separator, the waste steam pipe will then exit up the stack.

[gondolier88]

  Best way.

Greg

[Bunkerbarge]

Congratulations on getting somewhere with the engine, good to hear it is now settling down a bit.  I think the seperator tank on the port side will balance the gas tank out on the starboard side perfectly, not only from a ballasting point of view but also aesthetically.  The next decision is whether you make the seperator tank horizontal to match the gas tank or vertical, which is actually that bit more effective.

[kusuchi]

Looking really good. 

I'm afraid I'm with Giovanni when it comes to most scale figures, though Bernhard's may be the exception.

I have about seven or eight, at two different scales, I'm more than willing to part with.  The only cost would be packaging and shipping! 

I'll post photos if anyone is interested.

[andywright]

They would be worth seeing, and the heights of each one.
Andy

[kusuchi]

They would be worth seeing, and the heights of each one.
Andy

Hi Andy,

I'll post pictures.  But, I'll start another thread so I don't distract from your magnificent work. 

If you are interested, I'll give you first option on the two you most prefer.

[andywright]

Any one any ideas on prop size with a TRV1A, could fit a 2 1/4 inch no problem, at present I have a 50mm 4 blade, but its a kort nozzle prop, and I only fitted it as a temporary measure. I want to go as big as possible so as to run the engine slower and save steam, but don't want to overpower the engine. Could possibly get a 2 1/2 inch to fit.  Will stick to 3 blade for the proper propellor. The boat weighs about 6kg.
Andy

[gondolier88]

You want the engine to be slow revving, that's fine- however with the small pressures these engines run on you need to keep some decent rev's to have any recognisable power- I would say 75mm/3" at most.

Greg

[mogogear]

I'm with Greg on the prop size... but remind us -how long is your hull?...Er..launch?

[kiwimodeller]

I have the Gage single turning a 2 & 1/4 prop in a hull 920mm long and it pushes it no problem at 30psi so I think the twin cylinder version of the engine would easily swing a 3" prop. Hope this helps, Ian.

[mogogear]

I have the Gage single turning a 2 & 1/4 prop in a hull 920mm long and it pushes it no problem at 30psi so I think the twin cylinder version of the engine would easily swing a 3" prop. Hope this helps, Ian.

KiwiM...what hull do you  have your Gage in? have you posted a picture of it?

Thanks

[kiwimodeller]

The hull was started by a friend and then sat in a cupboard unfinished for many years. It was a Model Boats mag design from (I think) the 1980's called Ritalea which was meant to be electric but the Gage single and the 6 x 3 boiler fitted easily. I just modified the front deck and shortened the front cockpit so I could hide the disposable gas cylinder. I will try and post a picture of her under construction but I do not seem to have much luck posting pictures on here, no doubt down to my ignorance when it comes to uploading. Ian.

[andywright]

Ian,
I download mine to photo bucket, then cut and paste the link. I ought to upload my model tug pictures to there as well.

[kiwimodeller]

Hopefully this time two photos will be attached, one during construction showing the positioning of the boiler, engine and gas cylinder and one after the hull was finished. Cheers, Ian.

[mogogear]

Nice Ian--Glad to see that you worked out the photo posting...I still have issues over on RC groups -I just can't get my photos to appear like others over there.

Very nice deck -- !!