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[ooyah/2]

Derek,
You have quite misread Nicks post .
The check valves are in the pump, if you look at the configuration of the pump it's in the shape of a "T" with the pump ram driving up to the "T" bar.

There is a 3/16" nitrile ball in the suction side and and 1- on the deliver side, I know this for a fact as I designed and made the pump.

Now please do not take this wrongly, ,in my opinion you get far to involved in the technical side of full size practice which in most cases does not apply to our models.
Keep things simple and they inevitably work, your reference to Bernhards boats ,I must point out that Bernard is a master at building and fitting out models and fitting them out with the characters which makes his models second to non,  but doesn't make anything on the engineering side of things he only buys and fits them, so his experience of making pumps ,engines  and how they work is limited and he is guided by the makers of such items and has some items fitted that are not really required.

I have quite openly stated on this forum that most of the Gizmos that are bought and fitted to steam plants are unnecessary but if people wish to buy and fit them that's their prerogative to which I have no problem but not for me.

George.

[pettyofficernick]

Derek, Here's a couple of pictures of the pump, designed and built by George ( Ooyah 2 ) the check valves/non return valves call them as you will, are on the suction side ( the one with the push on pipe fitting ) and the delivery side, hope this helps....

[irishcarguy]

Lovely work so far Nick & even in the photograph it is possible to see the quality of the hull moulding. I like the idea of a steam setup but I have enough trouble with electrics & radios to keep me busy. One can always dream though, maybe some day I will figure it all out but then it would not be as much fun would it ?. Good luck with with your build, I will be watching all the way. Thank you for sharing, Mick B.

[pettyofficernick]

Hello Mick, fit and well now? Many thanks for the compliments, Steam engines are easy to figure out, I personally prefer chunks of metal and pipes to wires and batteries, there is something very satisfying  seeing your steam plant burst into life for the first time after bolting it all together, oily hands and burnt fingers are all part of the fun. There is also the routine of oiling around the engine, filling the boiler, emptying the condenser etc, it all adds to the fun. Lots more to do than switching on and sailing.....

[Norseman]

Steam engines are easy to figure out

I probably understand more about women .... Er probably not.
I will have a go one day but for now I'm just steam curious. So threads like this are a big encouragement Nick.

Dave

[pettyofficernick]

Oh yes, there is also the sound, and the smell of hot fog and oil.....

[pettyofficernick]

Next job to sort out was the engine controls, this has been achieved using Bowden cables, as they are nice and flexible and the runs will not be seen once the deck planking has been laid. The servos will sit underneath the bench that go's around the after area of the boat. No need to go into this in too greater depth, as the photos speak for themselves.

[southsteyne2]

Hi everyone just a small query your boiler seems to be bolted to the plant tray will this be insulated or lagged ? seems to me you will lose a lot of heat from your boiler
John

[pettyofficernick]

The boiler will be lagged in due course, once the layout has been finalized. I will loose little, if any heat through the tray, I have used basically the same mountings on all my past models with no problems.....

[southsteyne2]

Sorry no criticism meant just going by the picture also like the cable setup ,are these readily available and what source
Thanks
John

[pettyofficernick]

Hi, I have pondered the question of heat loss many times myself,  so no offense taken. I got the cable from Cornwall Model Boats, along with the fittings to attach to the servos etc. No connection with CMB other than as a satisfied customer.

http://www.cornwallmodelboats.co.uk/acatalog/installation_accessories.html#aG1173

[hammer]

No one has answered Derek's question dose he need a stop valve between the pump & clack?? If like me you use a hand pump to fill the boiler through a separate pipe. Maybe ?? I find there is not enough pressure initially to close the valves in my system, so I fitted a stop valve. I have a check list ( this is a habit from my pilot training) when preparing to sail, obviously the valve must be opened after filling when there is enough pressure.

[ooyah/2]

No one has answered Derek's question dose he need a stop valve between the pump & clack?? If like me you use a hand pump to fill the boiler through a separate pipe. Maybe ?? I find there is not enough pressure initially to close the valves in my system, so I fitted a stop valve. I have a check list ( this is a habit from my pilot training) when preparing to sail, obviously the valve must be opened after filling when there is enough pressure.

No,

George.

[Jerry C]

I'll have a go then. I didn't fit a valve between the feed pump and the clack valve and everything works ok. I DID however fit a bypass valve to overside through a flexi pipe. I use a 60cc syringe through this valve to fill the boiler. The feed pump non returns and the clack valve make the syringe into a pump sucking through the feed pump and discharging through the clack valve into the boiler. This also works.
Jerry.

[pettyofficernick]

I can't see where Derek asked about a stop valve, have I somehow missed a post? A stop valve is not needed, the one showh in the photos is the by pass valve, the output from this will eventually be piped overboard. Good idea to use a syringe as a pump to fill the boiler Jerry, I will have a go at that, it will also help to prime the pump.....

[Jerry C]

It does prime the pump but as the pump is positive displacement and under a positive head it is self priming in theory and in practice. I do however open the bypass valve to speed up the process and also to convince me that it is actually pumping. On closing the bypass you can hear the pump load up.
Jerry.

[pettyofficernick]

It does prime the pump but as the pump is positive displacement and under a positive head it is self priming in theory and in practice. I do however open the bypass valve to speed up the process and also to convince me that it is actually pumping. On closing the bypass you can hear the pump load up.
Jerry.

I am sure George said the pump was not self priming when I first got it, I may, however be mistaken, but during tests, I did prime it first with a syringe through the suction side....

[Jerry C]

A few more observations for what they're worth. I sail on Llyn Padarn which is crystal clear. My suction skin fitting is flush with the hull. I have no filter or gauze. I have also sailed for 7 miles on the Llangollen canal (6 gas tanks full). I've never had a blockage. The propshop screw never picks up weed. The 3 1/2" Maccsteam boiler/TVR1A/George's feed pump has proved to be a near perfect combination. The only problems I have had are, crud in the gas jet believed to be from extrusion lubricant left inside the copper pipe after production and a couple of flare ups on lighting the burner caused by not having the boat upright on lighting resulting in supplying the burner with liquid instead of gas. Bye bye one Welsh courtesy flag. Sorry boys. 6 quid up in smoke!
Jerry.

[Jerry C]

George initially designed the pump to operate with the pump valves vertical I was unable to fit it this way due to the situation in the boat I mounted mine horizontally and we were a little concerned that it might not work like this. It works fine.
Jerry.

[pettyofficernick]

Jerry, what size propeller are you using? I am thinking along the lines of 2 1/4" dia. x 3" pitch from propshop. Do you think that is about right?

[Jerry C]

I'm using a 2.75"x4.1" 3 blade. If doing it again I'd ask him to make me a 6" pitch version. 2.75" diameter was the largest I could physically get in. It works fine but the engine will turn a bigger coarser prop. Try one and then we'll all know. Anyone out there turned bigger with this engine?
Jerry.

[pettyofficernick]

Biggest I can physically fit in is 2 1/4", I am planning on using a 4 blade prop, I will, however, go for the 4.1" pitch....

[Jerry C]

Did you get any joy at Home and Bargains with a figure?

[pettyofficernick]

Did you get any joy at Home and Bargains with a figure?

Not as yet, not been out much due to being laid low with the mother of all chest infections, but I will have a look when I am near my local store. Can you remember the name of the 'boy band'?

[Jerry C]

Sorry, no but Hess got black hair and a grey hoody. Hips and shoulders move but not elbows or knees. About £5. Off the air now, Midsummer Murders.
Jerry.