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[kno3]

Hi!

It's been a while since I have received my Graham TVR1A twin cylinder marine engine kit, but I only got around to build it a few days ago. So I thought I would post some pictures of the assembly process.
This is how it arrived.

[kno3]

The instructions are very good and I didn't have any problems with the parts. All seem machined to fine tolerances, so everything fits together well. I was quite impressed that I only had to remove a few small chips left over from machining, nothing required bending, major shaping etc.

Since this is my first steam engine that I assemble from scratch, I followed the instructions and started with the base and crankshaft.

[kno3]

The valve gear links and clumns were next.

My only problem was related to the many kinds of tiny screws, all using imperial threads. It took a bit of guesswork to figure which goes where, as I'm only used to metric. I could never understand why one would find it convenient to express sizes in fractions??

[SteamboatPhil]

It certainly looks like a very well finished set of parts, I have heard that are a very good engine and extremely good value for money. Keep up the good work, and please post more pics / comments on your build  

[kno3]

Phil, I have to agree, it is a very realistic looking and complex marine engine. And yes, for the price you would otherwise get only a simple oscillator. The parts are incredibly small and precise. I forgot to use something in the pictures to show the scale, but the finished engine is only about the height of a package of cigarettes.

Now on to the next step. Nice as this kit may be, I thought that the cylinder base, originally square, is a bit bulky. So, inspired by another picture found on this forum, I decided to have a go at it with my calliper, drew the lines on, and then took it to the scroll saw. My idea was to leave only the protuberances needed to attach the cylinder base to the support columns.

However, I had a big problem: the saw blade got it's teeth curved when I turned the piece to cut in a corner, and because of that it dug into the edge, cutting more than i wanted. Luckily I had measured an extra millimetre for the edge, so I was able to repair that edge with a file, and still have enough material left to seat the cylinder well on it. That cut-out is a bit deeper than the others now, but it's hard to notice the difference.

[kno3]

Time for an update.
First I lapped the cylinder faces which need to be steam tight, then I departed from the instructions again and used rolled Teflon tape to seal the pistons, instead of the o-rings provided with the kit. Installing it was easy, but I wonder how well it will seal. It might take several tries until I get it to seal properly, as I don't know how much to compress the Teflon.

[kno3]

And now on to assembling the cylinders, now you can see what I tried to obtain by cutting out the cylinder base.
The piston rods are sealed by Teflon thread too.
Also added cross-head guides, then valves and chests.

[wideawake]

I have to say that it sems to be coming together very nicely.   Two thoughts.  Why did you opt for PTFE tape rather than the O-rings for piston rings?   Second, purely aesthetically, I think it's a pity they supply slot head screws rather than hex heads which would be closer to full-size practice.

Had I not bought the one I did on ebay (it looks similar but not identical to a TVR1A) I'd be very tempted to build one myself.   I particularly like your mod to the cylinder base plate.   It make the engine look much less "clunky" than it might have done without the change.

Looking forwrd to the next pictures.

Guy

[Bernhard]

hi,,,,,,,,,,looks great...nice littel  enginen it is ..........i have 3 off them........all made with hex bolt ...yes it look more real and better,,,,,,,Graham sell them to.........i have mine paintet to,,and made with the orings

regards Bernhard

[kno3]

Guy: I thought Teflon tape might reduce friction, and allow the engine to turn slower without stopping. I'll see how it works when I test it. If not, I can always put the original o-rings on. What engine did you buy on Ebay?

Bernhard: What colour did you paint yours? Can I see them? I'm thinking if I should paint mine too. I was considering having the aluminium parts anodized black, but couldn't find anyone to do it for me, so far.
Where does Graham offer hex screws for this engine? i didn't notice it on his website.

[kno3]

By the way, I installed the paper gaskets Graham supplies, because I'm not so sure about my lapping skills. Has anyone tried assembling it without gaskets? Does it leak?

Here are some more pictures. The engine assembled, with the cylinder covers still off, to adjust piston position and valve timing, which is easily done because both valve - and piston rods are threaded and can be locked with a nut.

[Bernhard]

Hi  ,,Green.........  yes they have the hex on  Graham weeb side...bot i got mine Engines ready made,,,,,,,i have a singel  1 to,.. here are they runing
 mine whas made with the gasket in,,+ sealer.

http://www.youtube.com/watch?v=CICE-XgTszA

http://www.youtube.com/watch?v=DJdS_g051WQ

http://www.youtube.com/watch?v=UQlqhgRgz9g

[kno3]

Very nice, so you painted the whole engine. i was thinking to leave the brass parts as they are and only paint the aluminium parts.
Will check Graham's website again.

[Bernhard]

hi......yes i like them look used,,,im not so happy fore all that bling -bling

http://www.youtube.com/watch?v=CICE-XgTszA

[kno3]

Here the finished engine with a marine flywheel.

[Bunkerbarge]

A really nice job there and very interesting to see it go together.  The modification to the cylinder base plate makes a big difference to the overall appearance and was well worth doing, you should suggest it to the manufacturer.

As for teflon, unfortunately it, unlike rubber, does not return to it's original shape when you compress it so I think yours will soon start to pass by the piston and you will loose perfromance.  The original "O" rings I am sure will be a far better proposition and will give better performance for a lot longer than teflon.

[Bernhard]

hi.......well don,,,,,,,look tip top-

[Bernhard]

hi,,,i forgot..on this i have a axel driven waterpump on.......from J.Hemmens.
regards Bernhard           
                            http://www.youtube.com/watch?v=CICE-XgTszA

[wideawake]

Guy:What engine did you buy on Ebay?

Hi Don

This is the ebay engine.  I'd be interested to know if anyone recognises the maker.  It's a bit of an oddity.  hackworth valve gear, metric fixings and somewhat sloppy linkages on the valve gear forward/reverse mechanism.   Hex screws on the cylinder head but tiny cross-point ones elsewhere.   Originally it had a black baseplate more suitable for display than use in a boat.   It runs fine on air but I've not  had steam through it yeta as it came without a lubricator.   I either need to buy one or make one.   Which will depend on how soon I can get some time in my model engineering workshop.

Cheers

Guy

[kno3]

Looks beautiful and indeed quite similar to Graham's. Please make a separate thread and show us some more pictures of it, as i can't really make out the valve gear linkage.



Now back to the Graham engine:

John: For the Teflon, I don't know, you might be right with the compression. But Regner recommends it and uses it an all pistons in their steam engines and I didn't hear that they are leaky?!

I tried to run it on air, but since I don't have a compressor, I used a foot pump (that I normally use for my bicycle), and it only turned when I pressed really hard on it. I could hear the air blow-by and come out of the exhaust without the engine turning. Then I remembered that I had forgotten to lap the steam valve faces. After lapping them the engine turns better.
Now I'm wondering if the Teflon seals well or not, because i did compress it a lot by rolling the piston between two wooden blocks, so it would fit in the cylinder. Perhaps I should have pressed less, to have a tighter fit in the cylinder.

I remember reading somewhere that the Teflon would expand somewhat in contact with oil and steam. Is this correct?

And what do you think about running the engine in under steam, since I have no air compressor? The manual recommends running in on air, but are there any specific reasons why I shouldn't do this with steam?

[wideawake]

Looks beautiful and indeed quite similar to Graham's. Please make a separate thread and show us some more pictures of it, as i can't really make out the valve gear linkage.

OK I'll try to do that later.   Got to do range tests on DX5e ATM while it's not raining!

Cheers

Guy

[wideawake]

As requested, I've started a new topic, Ebay engine - what is it?

http://www.modelboatmayhem.co.uk/forum/index.php?topic=14333.0

All comments appreciated.

Cheers

Guy

[Bunkerbarge]

There are other methods of running in an engine.  You can put it in a lathe, hold the crankshaft in the chuck, let the engine rest on the tool post somewhere and run the lathe slowly.  This is actually a good method as you can do it nice and slowly, adjust the speed and be in complete control.  If you don't have a lathe you can make up a rig with a pistol drill and do the same thing.

You will have to organise some means of putting oil into it though.  You can either arrange a tank with a drip feed into the inlet manifold or some sort of pressure system such as from a hypodermic syringe.  What ever you do you need to add oil regularly to it.

If you can't do any of these then you can run in directly on steam but the problem is that steam oil is designed to be used with the steam and is a very good lubricant.  For running in you really want to use a lighter oil to alow the parts to bed in initially before going back to steam oil later on in the process.  i use normal engine oil for running in.

I have now done a couple of engines on compressed air and it works really well and if you are looking at doing much more of this then a compressor might be a worthwhile investment.  You can then also use an airbrush and it is actually quite usefull when you are cleaning your engine parts to blow it all through.  Cheap ones can start at less than 100.00 pounds but I would suggest that you need a reservoir and a silent type is also a major advantage.  The cheapest of this type will set you back about 200.00 to 250.00 pounds but they are worth every penny.


...and you can pump your tyres up.

...and you can impress your mates by having all your engines run, one after the other.

...and you can blow up the li-lo.

...and you can chase the cat!

[MONAHAN STEAM MODELS]

Bunkerbarge,

I am never going to ask you to watch my cats if I am out of town!

Nick

[kno3]

Guys, I have changed to o-rings for sealing the pistons and it works well. I'll leave the Teflon for other occasions.

I also ran the engine in by turning it slowly with an electric drill set at slow speed and a flexible coupling. Turns much smoother now.