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[SailorGreg]

Well I thought I had - I've checked it several times, and when I run the engine on air it runs equally well on both forward and reverse "economy" settings, which suggests it's all symmetrical.  But I'll check it again as well as checking that nothing else has worked loose!

Greg

[Jerry C]

Greg, you've got the safety and boiler right. The gas tank filling is only a question of endurance and nothing to do with this running problem. The oiler is also working. The fact that at 35psi you can find a position on the reversing gear where the engine will run for 20minutes points to a fundamental timing issue. I'm with POMick on this one. Something you have done is not right. Read through again but with an open mind as if you'd never read them before. At each stage try to find another meaning from the one you had before. The fault I'm sure is in there somewhere. Going back to hydraulic lock, this happens only in the begining when everything past the steam outlet to the engine is cold. The engine clears this in a couple of seconds and everything heats up very quickly. Your lagging will certainly help with this. I have no drier on mine with no probs and graham tells you not to use one. Anyway matey you're making progress. Everything you can get right and eliminate is one step towards a solution. You will get there and we're all watching over your shoulder. Just wish you were a bit closer to me then I could come over and help. It's so difficult having to do it like this. Imagine doing it pre Internet.
Jerry.

[ooyah/2]

Well Jerry you've drawn the short straw and as you are nearest to Greg just pop down and see him.
 Greg
 Yes I have to agree with both Jerry and Nick I am sure that it's a timing problem and the most likely thing is that the slide valve isn't equal in it's travel, as I have said I don't know much about the TVR but I think that it's holes that are drilled for ports rather than slots.
 When timing a D10 or 10V and most other slide valve engines with the crank at T.D.C the valve should be set so that a crack is seen as you rotate the engine shaft in the direction that you want it to run and at B.D.C. it should be the same and then do likewise for the other cylinder.
 This means that steam admission is just after T.D.C and  B.D.C.
 On my D10 I set the Stevenson revers gear fully open and let steam enter the engine while turning the shaft over via the prop by hand and the amount of condensate spewing out before the engine starts is quite something and as I had the exhaust directed up the funnel I used to get a very hot shower.
 I made a bypass valve on the exhaust line which directed the condensate overboard into a can and when the engine is running clean I redirect the exhaust back up the funnel.
 So condensate causing a hydraulic lock isn't confined to the TVR.
 
 If I could I would post some pics of my bypass valve but since the change over it's not possible to post pics on the forum via my MAC..
 
 Hope this helps
 
 George.
 
 

[pettyofficernick]

Hi Greg, just a thought, referring to p14 of the instruction manual, are you sure you have done as instructed re setting the position of the eccentric, ie  front piston at tdc, adjust rear eccentric and vice versa, I seem to remember a thread where someone had a similar problem, and it turned out that was the cause of his woes. I have looked for the thread and can't find it, perhaps Jerry or George may have seen it and can remember its title.
Nearly there,
Regards,
Nick.

[SailorGreg]

Thanks all for your continued interest and support - and in particular George who PM'ed me some good info on timing slide valve engines.  I plan to go back to square one in the next few days and, as Jerry suggests, approach this with a completely open mind - or try to at least. I can normally do "blind faith" or "completely blank" but I can't say I've practised "open mind" much!

More news when I have made progress.  (There ought to be a "crossed fingers" smiley at this point.)

And if this all takes a little while - Merry Christmas everyone!

And if it takes a really long time - Happy New Year!!

Greg

[pettyofficernick]

Thanks all for your continued interest and support - and in particular George who PM'ed me some good info on timing slide valve engines.  I plan to go back to square one in the next few days and, as Jerry suggests, approach this with a completely open mind - or try to at least. I can normally do "blind faith" or "completely blank" but I can't say I've practised "open mind" much!

More news when I have made progress.  (There ought to be a "crossed fingers" smiley at this point.)

And if this all takes a little while - Merry Christmas everyone!

And if it takes a really long time - Happy New Year!!

Greg

And a merry Christmas to you to.....

[Jerry C]

Greg, seasons greetings. Correct way to find tdc. Remove cylinder cover. Rotate crankshaft to approx tdc. Fix with blue tack a protractor centered on flywheel. Fix pointer towards zero. Set calliper depth gauge to half stroke value and lock it. Without disturbing the protractor rotate crankshaft anticlockwise to below mid stroke. Put depth gauge down the bore with calliper body resting across top of cylinder. Slowly rotate crankshaft clockwise until piston contacts depth probe. Note reading on protractor. Rotate crankshaft clockwise, over tdc to below mid stroke on the other side. Replace depth gauge as before. Slowly rotate crankshaft anticlockwise until piston contacts the probe. Note reading on the protractor. Both reading should be the same but usually won't be. If one is 88deg and tother is 92deg then rotate protractor on flywheel 2deg, keeping flywheel still. Repeat process until both readings are the same. Then and only then rotate crankshaft to zero and voila, you have accurate tdc. The reason for this procedure is because the rate of change of a sinusoidal waveform where tdc is zero tends towards zero at tdc, whereas rate of change tends towards maximum at 90 deg or midstroke. Or in plain lingo you can move the crank a large distance at tdc without moving the piston but at midstroke a small rotation of crankshaft moves piston more. Sounds complicated but easier to do than say.
Jerry.
Ps you can better use a dial gauge instead of calipers.

[SailorGreg]

Thanks again for all the advice.  I have gone over the timing again and as far as my inexperienced eye can see it is spot on - well, as spot on as I can get it.  The biggest variable I think is my judgement of the port exposure at each end of the valve stroke being the same.  It is the same as far as I can judge it, and I have been viewing it with a magnifying glass under a strong light.  So I have to assume the timing is, if not perfect, at least good enough to get the engine to run consistently.

One thing I did notice when doing the timing.  As I turned the engine over slowly by hand, occasionally I would get a "catch" - the engine stiffened up for a moment until I had turned it beyond that point.  Very occasionally this catch stopped the engine completely - I couldn't turn it at all without reversing the direction.  This appeared to be caused by the eccentric strap jamming on the eccentric.  I had noticed before that the strap could move back and forth a little but hadn't really noticed that this was causing friction in the engine.  It seems that when the strap is in tension it rides smoothly on the eccentric but when it is in compression it moves a little off the eccentric towards the adjacent bearing. Here are a couple of pictures - the first is the strap correctly seated on the eccentric, the second with it jammed against the bearing housing - you can see where wear has occurred here.





The strap does seem quite loose on the eccentric, but the only other "slop" I can find in the whole linkage is where the strap is connected to the male slide - there's a small gap of about 0.5mm which allows the top of the strap to float back and forth by that amount.  Mind the gap -



That bolt is done up as far as it will go - I guess it is bottoming out in the threaded hole which prevents the head butting up to the collar of the slide which just protrudes from the strap.  All this might explain the reluctant running and occasional full stop I have been getting.  My question is - do others have these movements in the eccentric strap, has it caused problems and what if anything has anyone done to address it?

Sorry, this is getting a bit down-in-the-weeds for the casual reader.  Hope I'm not boring you! 

Greg

[Jerry C]

Greg, the third photo shows the valve gear out of line with the valve stem. When the eccentric binds try rotating that pillar a fraction anticlockwise until all lines up. Ditto other end. Might help.
Jerry.

[pettyofficernick]

Greg, the third photo shows the valve gear out of line with the valve stem. When the eccentric binds try rotating that pillar a fraction anticlockwise until all lines up. Ditto other end. Might help.
Jerry.

Indeed, I used a straight edge across the flats to get then squared up properly.

[ooyah/2]

Greg,

No 1
I have had a look at the engine in my possession at present and it has slotted screws were yours has hex bolts.
Take the bolt, hold it in your vice and file at 45 deg, then move the hex around filing  on all 6- sides, then square of the bolt which will make it that bit shorter, or if you have the original slotted screw put that in and see if the eccentric strap still wonders.
I am assuming that you don't have a lathe, if you have one put the hex in the 3- jaw and file a bit off the bottom.

No 2
Check that the eccentric sheave is in the correct position, loosen the grub screw and rotate the shaft and if you have completed No 1 the sheave should slide into its correct position.

If after No 1 & No 2 it still wonders,

No 3
loosen the screws top and bottom of the support columns and they will automatically line up after all of the other checks have been made, don't forget to re- tighten them. 

The only other thing that I can think of is there any of the links bent?

George.

[logoman]

One thing I did notice when doing the timing.  As I turned the engine over slowly by hand, occasionally I would get a "catch" - the engine stiffened up for a moment until I had turned it beyond that point....
....My question is - do others have these movements in the eccentric strap, has it caused problems and what if anything has anyone done to address it?
[size=78%]Greg[/size]

I checked my engine and I also see the strap wandering. I had not noticed this before and so wish to thank you for this thread. It does not catch the bearing, but i do feel a very slight stiff spot when turning it over, which i'd assumed was a little compression in the cylinder; now i think it is strap alignment. Thanks also to George, Nick and Gerry for suggesting ways to correct this. 

[SailorGreg]

Phew! That was a hectic Christmas.  Still managed to find a few a moments to play with the steam engine.  I changed the slightly long bolt in the linkage for the original screw and that reduced the movement a little bit.  Once I am fully sorted I'll shorten the hex head bolt and put that back.  For the moment I'm focussed on getting the engine to run reliably.  I checked all the points suggested by George and made sure I really was reading the timing instructions correctly - I was!  I have also played with the timing a fair bit.  I am realising that a tiny adjustment on the valve stem (screwing up or down a fraction of a turn) can make a noticeable difference to the smoothness and reliability of the engine.  It is certainly getting better, and if I set it going and leave it alone it keeps going.  It will change direction (fairly) reliably - occasionally needs a to-and-fro on the lever to get going again - and responds well to the throttle as long as I keep the engine running.  However, if I try and stop it by closing the throttle and then open it again, I sometimes get the  "locked solid" feeling.  I can't even move the fwd/reverse lever, the engine won't turn and I have to leave it for a while before gently wiggling it back to life.  This is something to do with running on steam - the engine will run all day, stop, start, tick over or race when I use compressed air, but steam seems to get things binding up somehow.  Nevertheless, things are getting better and I will persevere.

Santa was as good as his word, and I now have something to take my steam plant afloat.



This was ordered quite late in the day and I must applaud Models by Design who still got it under the tree in time for Christmas.  Great service!

I am not sure I will use the deck moulding.  I'm not too keen on the way it narrows in the forward part.  Apart from anything else, my fat fingers are going to need all the space they can get!  Nothing decided yet, but I'm drawing plans for wooden deck beams and planking and when I've done that I'll make my choice.  Incidentally, is there any reason that I shouldn't build my water tank into the bow rather than having a separate tank?  It seems perfectly straightforward to glue in a couple of bulkheads to form the tank, but nobody seems to do it that way.  Why?

Well, I guess it will be next year before I report any more on this, so Happy New Year to everyone, and let's hope the weather in 2013 is a little kinder for boats and sailing.

Greg

[scoots]

Hi Greg,
 
For the Solent, have a look at this Andy's page : http://www.windpowersails.8m.com/photo4_1.html
 
Happy new year to all !
 
Alain

[SailorGreg]

Thanks Alain, I have seen Andy's Solent before and it was his lovely work that swayed me to choose the Solent over the other hulls I was considering. 

Logoman - if you find a way to keep the eccentric straps from moving around, do please let us know - I'd be very interested!      It's obviously not something that affects the running of other TVRs, based on the number of successful installations there are out there, so maybe my little issue will go away with time - it's already becoming less of a problem each time I run the engine.

I am starting on the Solent build now and will start a separate thread on that.  I will continue to run the TVR to learn more about its little foibles, and I still need to plumb in the water for topping up the boiler with George's pump.  But space on the bench isn't limitless and a change is, apparently, as good as a rest - so it's boat building for a little while now, with occasional steamy sessions when I get the time.  If I come to any big decisions or difficult bits with the engine I'll come back here to seek the collected wisdom of the forum.  In the meantime, a very big thank-you to all who have helped, encouraged and commented - I suspect I'd have had a dire time without your steadying hands  .

Greg

[SailorGreg]

In my plan for the TVR1A steam plant I included a gas regulator (attenuator), the BIX029 from Forest Classics.  I ordered this back in the autumn, and was told that due to poor health of the chap who makes it, it might be some time before it arrived.  At that time, that was not an issue.  Well, it has become an issue and I have now cancelled that order.  I've had several promises of delivery, each one missed (last one was within 10-14 days on 6th January) but to date no attenuator and no communication explaining the absence. It's just a bit sad that this item is still advertised on the front page of the Forest Classics website when it is clearly discontinued.

So - is there any other product I can get to do this job?  I know some folk have made their own but my metal working skills are below basic - I can barely file a straight edge, so making a complex valve like this is a long way down the line for me.  Is there an equivalent to the BIX029 available?  I've looked but I haven't found it.

It's not the end of the world if I can't find one - there are loads of steam plants out there running without a gas regulator.  If I can't source one in the next month I'll rework my piping to remove the pressure feed for the attenuator I have built in.  But if you know of something....?

Disappointed but hopeful of Hayling

Greg

[derekwarner]

Greg......the French manufacturer ANTON produce a number of gas regulators.... but the WEB site is not all that user friendly
The Swiss distributor KRAMER  markets the ANTON product and their part number for the same item is I believe V78
Both of these are probably x 2.5 on the cost of the BIX029
As you say ....probably the majority of gas fired model steam plants do not have a gas regulator........however yes they do save both gas & water ...
Probably a "nice to have  rather than a necessity" .....Derek
___________________________________________________________________________________________
 Les Régulateurs de gaz V71Lors de l'installation d'un groupe vapeur dans votre bateau,     survient la question sécurité : comment baisser le brûleur     quand la pression de la chaudière est atteinte ?
    Deux solutions : le régulateur gaz simple ou le régulateur gaz     bi-membraneGas regulator to regulate the boiler pressure acting on the flow of gas to the burner. The operation of this type of regulator is generally governed by a single membrane and a gas control valve, the pressure of water from one side of the membrane and gas across this same membrane pressure. When the boiler has reached the set operating pressure, the burner will automatically on the back burner. The regulator therefore saves gas and facilitates relaxation. It also allows saving consumption of water in the boiler while avoiding the inadvertent discharge of the valve.This is no classic gas regulator, proposed by ANTON workshops

[Jerry C]

Hi again Greg. I also planned to include a gas control valve on my build but was advised by "people that know" to keep it simple at first until your au fait avec votre plant. I could always fit one later. I chose to follow that advice. Since then I have found that the 3 1/2" Maccsteam, TVR1A and George's feed pump to be such a perfect combination that I have had no need of a GCV at all. If I find the safety lifting then running the engine lowers the pressure. In use I average around the 20 to 30 psi mark. I also found that the burner is not all that reduceable anyway. So I'm quite happy not to have one. When all is finished and you're at the lake you'll find you've plenty to be getting on with. I get 40 minute sessions out of my combo and find that plenty
As my arms hurt holding the Tx after that long. And it's thirsty work. Nearly summer, crack on matey.
Jerry.

[pettyofficernick]

Hi Greg, I tried one but was not all that impressed with it, I get about half an hour out of my Maccsteam 3.5 horizontal and SVS engine without a feed pump, which for me, is a long enough run. You can have my Bix one for far less than retail if you want it, but as Jerry says, you don't really need one.

[SailorGreg]

Thanks guys - and thanks Nick for the offer.  From what you say the attenuator really is an optional extra, and perhaps circumstances have led me to a simpler setup and saved me another layer of hassle in setting up.  The Anton fitting looks very nice, but it's a bit rich for my blood I'm afraid.  I'll put the attenuator idea to one side for now, and if I ever get to the stage of needing a longer run time then I can always revisit it.

Sorry Jerry, what was that word you used - summer ?  No, don't recognise that one, is it some foreign word?   

Greg

[Jerry C]

Know what you mean Greg. I've put modelling to one side at the moment. Don't want anything sharp too near my wrists!! That said the weather here has been really good this winter, long periods of brilliant sunshine and calm but always soooo cold. The views of Sowdonia priceless.
Jerry.

[Circlip]

At that time, that was not an issue.  Well, it has become an issue and I have now cancelled that order.

Pity that Forest seem to have put all their eggs in one basket. Would have thought a few could have been manufactured by someone else to keep customers happy?
 
  Regards  Ian

[Landlocked]

Greg,

If you get the BIX, don't install it backwards!!! Trust me on this one! 
Jerry,

I thought you were a regular bloke until you threw the French in

"to keep it simple at first until your au fait avec votre plant." What the heck does that mean?  My Google translator gave me "to do with your"

Also, I don't understand the reference to thirsty work.  We have a solution over here.


[/size]
Ken/Landlocked

[KNO3]

What happened to this project, is it finished?

[SailorGreg]

Yes, finished and installed.  My build of the steam launch sort of took over from this thread so you need to go there to see the TVR in its rightful place.