Falcor

[martin ranson 2Participant @martinranson2]

TO JASON B please … thanks for the hint, message received … however I do prefer to only answer questions on the public forum … for example Petes` question above, about lighting the gas flame … I assume that may be of use to other people … if I start using 2 places to answer questions then I get less time in the shed "metal-bashing" … even if I get into trouble with SWMBO because I should be mowing the grass.

martin

[Peter Russell 4Participant @peterrussell4]

Martin

Well Ive had the chasis running on compressed air after a few minor mishaps!

The eccentric rod 10ba snapped as the outer valve crank pin was too long and hit the hex head screw adjacent.

The screw is now csk and the eccentric link now 2mm and a 10 ba screw opposite the 2mm drive link helping to keep the cam and strap together.

Ive tried making the wood casing but not got a very good result due to getting the angles of the strips right and consistent.

So I have got a spare bit of boiler tube and wrapped a layer of insulation on it then started winding on 6 or 8 layers of mahogany veneer fully glueing each layer. When its dry Ill cut it off the tube as it needs and make the pieces as you did Im also adding a brass cup at each end of the wood to hide the ends.

When I raised steam with the boiler on the hearth in the work shop I got a better more stable flame by blocking both the smaller burner bar air holes and closing half of each of the larger holes. With the holes open the flame tended to only work on 2/3 of the burner bar slots and lift off and blow out.

Hopefully by this time next week I will have run it on my piece of test track and hope SWMBO gets some more track for a Xmas present – well you can hope cant you!!

Then its close the workshop down for the winter its too cold and damp and the machines have to be wrapped up in anti rust paper and polythene sheets after which when the snow melts I can start painting.

Regards

Pete

[martin ranson 2Participant @martinranson2]

HI PETE … nice to hear from you … I am not too sure which 10 BA bit was too long … I assume you mean the bell crank shown in figure 48 … but you seem to have sorted it … when you put the chassis on compressed air how much air pressure did it take to run slowly ? … mine will run totally free on about 4 PSI and needs about 8 PSI on my home-made rolling road.

As regards the burner, all I can suggest is to check all the dimensions and check how much gas pressure is arriving at the jet … figure 20 shows the gas restrictor … it should be possible to slow the gas down with this restrictor … too much pressure is a common cause of the flames lifting off the burner surface. A few months back we were talking about the I.D. of the fire tube in the boiler … you used thick wall tubing if I remember correctly ?

If you are closing down the workshop for winter, that is a real shame … is there no way of adding some insulation on the inside of the "shed" walls ? maybe polystyrene blocks faced with ply ? you must be very patient … I could not wait 4 or 5 months to get back in there.

martin

[Peter Russell 4Participant @peterrussell4]

Bell crank bolt fig 47

Pressures no where near that low may be 1.5 bar but I have now run it on steam!!!!

So now I eat humble pie- the restrictor rings for the burner bar air are now absent – although I got a bigger flame with them clearly it was not hot enough to raise enough steam to run it on blocks

I reverted to the correct burner tube size.

Burner pressure is about 15 psi

Are you aware that there are 2 versions of the ronson gas valve?

The one in your picture and one where the vent groove is half way down

Ebay Ronson gas valve – the vent its far enough down not to need any slots if thickness of gas tank end plate is ok

Also a chap called Bruno in Sweden makes an adaptor which is M8 fine thread to to any current ronson valve.

Saves a lot of messing about.

Ive been in touch with my local model engineering society in Cheltenham and they can do boiler tests and certification for a membership fee of £30 pa.

They only open on Sunday at this time of year – but will be visiting in next couple of weeks to talk to them about labels and identification.

I closed the shed down last year about this time the walls are already clad with formica boarding above bench level so only realistic thing I can do is lag the roof – but if you will insist on firing a loco up till the SV blows and fills the shed with steam and rain there aint a lot you can do!!!!!

Ive designed a little "tender" for the radio gear and SWMBO is going to assemble it under guidance.

Ive fitted a servo under the cab floor for the throttle but as its only half a turn its not too good – going to see if I can increase the throw to open the valve further – the steam valve is a Roundhouse RC valve.

Pete

[Peter Russell 4Participant @peterrussell4]

Martin

One small thing I forgot where did you get the lagging string from as I cant find it and the only ref I can find is use ordinary string painted white!

Pete

[martin ranson 2Participant @martinranson2]

HI PETE … looks like the loco is progressing O.K. … if it needs about 1.5 bar, or 22 PSI, to spin over with the wheels clear of the floor, then possibly there may be a few tight spots to "ease" with a reamer or a file … possibly the valves are not QUITE in the right place … equal travel each end and correct timing can make a dramatic difference to performance … how did you manage to get SWMBO to build a tender for you ?? when I mentioned this to my SWMBO she said something like "bleep bleep deleted" and marched off to her sewing room.

For the string could I suggest you find the nearest large shop with a haberdashery department … the string I always use comes from there … lots of colours and sizes … the reel I have at the moment is WENDY SUPREME LUXURY COTTON DK, coloured white … I assume DK means double knitting … I smear the length of tubing with lots of 1 hour epoxy resin, and then I tie one end of the string into place with a single knot and start winding as neatly as possible … tie off the other end with a single knot and wipe all the surplus resin off the exterior of the string … leave to dry overnight … give the exterior a light sanding to get rid of all the prickly bits.

Nearly forgot, use a pair of disposable gloves `cos it`s a bit messy on the fingers.

For the paint just use ordinary household emulsion … mine is Dulux matt white … put some in a small container like an eggcup and fill it about 3/4 … add a bit of water to dilute slightly … stir it in … apply 2 or 3 coats … again use some fine sandpaper to smooth off any remaining prickly bits … I have used this method for over 30 years and it is very durable … if it gets mucky simply repaint it.

martin

[Peter Russell 4Participant @peterrussell4]

Martin

Admittedly I have not lagged the pipework yet but what would be your views on adding a supperheater as the steam/exhaust is very wet!

I thought if 2 1/8 holes were drilled in the burner bar bush that has the two anti whiste notches filed in it and a legnth of 1/8 pipe could be fed down beside the burner tube coiled to fit the inside of the 22mm pipe beyond the burner.

then couple it up after the lubricator so its between the output of the lubricator and the input of the T under the boiler at the front.

Regards

Pete

[martin ranson 2Participant @martinranson2]

HI PETE … as regards the superheater … you obviously like experimenting … go for it … no guarantees though … I assume you are putting a loop in the 1/8 pipe to take it back out more or less where it came in … let me know how you get on … I have occasionally thought about it, but never got round to it.

I do know some of the commercial makers feed a length of pipe all the way down the fire tube so it arrives in the smokebox and then down to the cylinders.

For any superheater just make sure there is no soft solder anywhere too close.

Please tell me how you get on.

martin

[Peter Russell 4Participant @peterrussell4]

Martin

Just a small clarification

when the regulator is operated by a servo how far does it open ? standard servos only rotate just over 180 deg

regards

Pete

[martin ranson 2Participant @martinranson2]

HI PETE … the R/C valve you ask about … it was covered in parts 1 and 2 … page 355 explains the modifications … photos 6 and 10 show the valve … figure 12 is the drawing … the valve I used was an old one with a coarse thread … some types achieve full opening in a small amount of turning by having a very blunt cone on the valve spindle … this is the opposite idea of a long slender needle valve.

If your servo turns by 180 degrees whose make is it please ? … all mine turn by about 40 or 45 degrees either side of centre … this gives a total movement of a bit less than 90 degrees ( a right angle ).

Some people use a long radius arm on the servo to drive a short radius arm on the valve. This needs care with assembly or else the valve arm can flip over centre !!

Some people cut their own coarse threads by using the lathe to produce the coarse pitch … if you use commercial taps and dies then the most coarse one I know is 1/4 Whitworth, this is 1/4 x 20 thread … if there is another type then perhaps someone will let me know ?? Something about 3/16 or 5mm would be useful ??

I have seen some people use 2 gears mounted on the valve body … so 90 degrees movement on the servo drives the valve spindle by twice as much which is 180 degrees.

hope this helps.

martin

[Peter Russell 4Participant @peterrussell4]

Jason

Can you advise how to insert a picture please

Pete

[Peter Russell 4Participant @peterrussell4]

Martin

When I say 180 deg that is total rotation – my transmitter allows me to do end to end and centre either way.

there ae sail winch servos that do 2 – 6 or even continuous rotation. look at servo shop web site.

Ive asked Jason to tell me how to attach a picture – Ive made super heater but have not tried it yet

Pete

[JasonBModerator @jasonb]

Posting photos

[martin ranson 2Participant @martinranson2]

HI PETE … I am still not sure how you intend to drive the valve spindle ?? obviously a sail winch can do multiple turns, so are you intending to couple this directly to the valve spindle ?? It might not fit in the cab though ??

If you use a small size standard servo under the floor, surely it would be rather dodgy to try to make a simple linkage to swing the valve operating arm by 90 degrees each way of centre ?? However clever the transmitter is, it must end up shoving a servo arm in one direction or the other ??

I am surprised the Roundhouse valve is not suitable, there are thousands of these in use with radio control locos … I assume you do not want to make your own valve ?

still confused … martin

[JasonBModerator @jasonb]

I'm almost certain that the roundhouse RC valves are 1/4 turn, think of a household isolating valve so you can work them with a bog standard radio and servos with 90deg rotation, no need for fancy digital one where the arc of rotation can be preset.

Its only the manual valve sthat use a needle where the lever is rotated right round by hand.

[Peter Russell 4Participant @peterrussell4]

martin

I hope this works – picture of superheater Pete

[Stuart Smith 5Participant @stuartsmith5]

I have just started assembling a Roundhouse Lady Anne loco kit. I bought the RC fittings kit as an extra, so I ended up with 2 steam regulators. The original kit came with one for manual operation and the optional RC kit came with a replacement for use with a standard servo. I haven't tried either yet, but the instructions show the RC version just being used with a normal servo.

I have opened both valves to see what the difference is. The standard manual one has a fine thread with a cone shaped needle valve. The RC one has a coarse thread with an o ring end.

I have taken a photo of each & put them in my photo album.

Stuart

[martin ranson 2Participant @martinranson2]

HI PETE … just a thought about your transmitter … if it does not work very well with the Roundhouse valve, then are there any "rate switches" on the transmitter to adjust ? … it might be called something else on your transmitter … moving one of the 4 main sticks from one end to the other of its travel will move a servo by a certain amount … instead of the old method of adjusting linkages, the amount of servo travel can be set electronically on various transmitters … is there a switch, a potentiometer or a bit of electronic button pushing to set up, to match the required servo travel for each channel ? For the same amount of stick movement the servo will move less or more.

Looking at the superheater … wow, that is a lot of surface area in the coil … that will certainly warm up the steam flowing through it … maybe more than you need ? Have you tried the assembly by using a spare piece of copper tube away from the boiler ? ( do not burn your fingers ) It may be worth double-checking that there is no tendency for the flame to head out backwards into the cab instead of up the smokebox and chimney … the coil could be causing quit a lot of obstruction to the gas flow … I would consider experimenting with smaller amounts of 1/8 tube inside the fire tube before I built everything into the cab … however, if it does work it would certainly be more economical than my loco.

martin

[JasonBModerator @jasonb]

You also want to set the throttle gimble so it is off centre as you won't be needing reverse, that way you get more movement when pushed forwards. Or better still a ratchet setting rather than a sprung gimble then you get full throw and can let go of the tranny.

 

Could be the first Flash Steam Falcor

Edited By JasonB on 27/11/2018 18:52:35

[Author]

Posts