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Author Topic: Flash steam plant control.  (Read 95771 times)

Xtian29

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Re: Flash steam plant control.
« Reply #200 on: August 08, 2011, 08:38:22 PM »

Well,  I think nothing short of a full "Reverse osmosis" plant is needed here! It goes without saying that it would be completely autonomous, and would only be fitted to end the irksome task of visually monitoring the feed water supply level, and also I suppose because you can.....:o

I thoroughly enjoyed the visit down south. I passed through some old haunts like Bracknell, Broadmoor! and Camberley on the way to Guildford. I wish I had brought a list of the imperial reamers and taps and dies that my Stuart D10 build is going to need. Never mind, I got a brand spanking new 1" NPT tap for £8 off one of the stalls for my brewery ( It is a USA pipe thread, required for the 4.5kW heater elements)

I am building a water pump, and have hopefully conned my "secret sponsors"  into obtaining an electric motor with a 100/1 gearbox from RS

I forgot to "feel" VB while it was at full throttle to get a sense of the vibrations it generated, although it seems from the lack of 360 degree ripples, that it is not a problem, but I will be actually be sitting in my boat, so I don't want to develop "whitearse" from the dreaded vibrations :o

Is there any heads up on the publication date of your article? I emailed the mag for a date, but got no answer. Hopeless!

By a strange coincidence, and totally unconnected with my powers of persuasion, my "sponsors" have just started using picaxe chips to build up all the R&D circuitry we need for "mood lighting" drive motor control for "electric spoilers" etc. We have now got the £60 software to directly test the circuitry in a virtual circuit and also generate the PCB layout ready to be sent off for PCB manufacture. We were using dedicated little micro controllers at about £90 each, but the electronics boffin is well pleased now I have pointed out the error of his ways, and set him on the path of picaxes. This means we will soon have an in house picaxe boffin who can help me write some sort of control program, something which I feel is well beyond the wit of ordinary man, namely me.

Looking forward to all progress

Rog, AKA "Silverbrewer"
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flashtwo

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Re: Flash steam plant control.
« Reply #201 on: August 09, 2011, 06:51:04 PM »

Hi Rog,

I read somewhere that the PICAxe project boards software didn't handle negative numbers and that their standard code for driving servos caused glitches every now and then. Things may have changed, but its something to consider when using them.

Any vibrations on the D10 are mainly caused by the pistons hitting TDC or BDC, something to be eliminated by careful machining of the piston rod to the correct length ( I have built up a selection of them!) and allowing for any up-down slack on the main bearings.

I did make a vibration head out of a musical Christmas card piezo sounder, mounting it on a magnetic base and displaying the signal on a 'scope along with the shaft pulse signal. By using a protractor, I could determine exactly where on the cycle the peak vibration occured.

I'll try and find out about the possible publication date.

Ian

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Subculture

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Re: Flash steam plant control.
« Reply #202 on: August 09, 2011, 07:27:05 PM »

You can use the 'pulse out' command for servo control instead of the 'servo' command on Picaxe. it works just as well, but has no glitching issues (which I belive only affected some of the lower spec Picaxe microcontrollers, now superceded).

flashtwo

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Re: Flash steam plant control.
« Reply #203 on: August 10, 2011, 09:04:38 AM »

Thanks Subculture for clarifying the glitching problem on the PICAxe boards.

Ian.
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Xtian29

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Re: Flash steam plant control.
« Reply #204 on: August 10, 2011, 05:13:59 PM »

To counteract the Picaxe chip negative number thing, I believe you tell it to treat a number somewhere centrally placed within it's count range as zero. I do not have a manual handy, but they count from zero up to let's say 255, and if you add one more to the max number it can cope with it cycles round to zero.

So making it treat 127 as zero gives you zero, with >127 indicating a positive result and <127 indicating a negative result, within the constraints of it's max counting ability.

I assume there is no reason why the arbitrary zero point cannot be set to a lower point if there is not much expectation of large negative numbers and a larger positive range is required, like you would need if you were to be mad enough to make a jet steam engine that melted things for instance  :}
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flashtwo

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Re: Flash steam plant control.
« Reply #205 on: August 10, 2011, 11:35:20 PM »

Hi Rog,

Yes, you're right. You can use the most signifcant bit (bit 7) as the polarity indicator - if it is zero then the bits 0 to 6 represent a positive number and conversely, if set to 1 then the other bits represent a negative number. You can use this with any number of bytes representing a single variable, with the most significant bit in the most significant byte defining the polarity. It is this method that is used in my code written in assembly language.

Although I have never used the PICAxe boards, I thought it may have been the supplied suite of higher level functions ( + - * / ), that had the negative number problem - I'm most likely wrong and it would be good to knock this one on the head.

Regarding the steam jet engine - I'm just starting on the new experimental version now that Vital Byte's vertical boiler is working satisfactory.

Ian.
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Xtian29

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Re: Flash steam plant control.
« Reply #206 on: August 21, 2011, 04:12:05 PM »

I have got myself an electric motor with a 100:1 gearbox for initial testing (RS 417-9661) which is exactly the same as the one in Vital Byte. Do you have two fitted because you thought redundancy on the pump would make sense, or have you actually had problems in the past that made two pumps a necessity? If so, and just for interest, which part gave the problems, the motor or the valve balls? Do the pumps have individual water inlets to cover for blockage at the inlet? I will get another pump motor later ...

I am doctoring a pump drawing I have, ( from Ray Hasbrouck No 8 engine plans) I am doing it half size, and in metric, which equates to 1" stroke x 1/4" bore and I will fit a 6 mm to 6mm drive coupling from RS. (748-320) Your Oldham style couplings were of your own making weren't they? Hopefully 6mm drive shafts will suffice as I wish to keep the weight down.

I have found a bearing supplier ( pt&bearings ) who supply "our" sizes of bearings at prices ranging from dirt cheap (for "cheap skateboard" kind of stuff,) to reasonably priced SKF quality. This is where I will source the bearings for whatever I make unless you guys know of somewhere better.....http://stores.ebay.co.uk/PT-AND-BEARINGS

Went to Smiths today to look at the engineering magazines, and found none! So either there is an upsurge in interest, or they aren't stocking them any more!  :o  
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flashtwo

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Re: Flash steam plant control.
« Reply #207 on: August 22, 2011, 10:20:01 PM »

Hi Rog,

The prime reason for the two pumps was redundancy, but they are useful for:-

a) Boiler filling - the computer is instructed to run both pumps at full power just to speed up the initial filling of the boiler and engine.

b) Extra capacity - so that when the first ("A") pump is at full power the second ("B") can start delivering extra feed. The feed controller output is scaled 0 to 200% with      the "A" pump covering the 0 to 100% and the "B" 100 to 200% range. This was useful during the experimenting phase.

c) If there are any pond side problems, I can make the "B" pump the primary and the "A" pump the secondary.

d) The computer always monitors the speed probe pulses from the pumps and if the primary pump stops turning, the computer automatically switches to the standby pump within 6 seconds. This has happened once on the lake and I didn't notice until the boat returned to shore.


The problems that I have had are:-

a) Ram grease contaminating the outlet ball valve seat and preventing a good seal. This has been the most common problem, so that now I just use a drop of steam oil on the ram.
 
b) The brass seat becoming uneven for some reason and letting by. I re-seated it by using a sacrificial ball and tapping it with a small hammer. This has only happened once.

c) A motor bearing wearing out causing the motor to stick. I replaced the motor.

The pumps share an output from the water filter which has separate intakes on either side of the hull.

You must ensure that you have actual feed water flowing through to the engine outlet before igniting the boiler otherwise you will get slugs of very high temperature steam hitting the engine.

I did design the pumps so that both the inlet and outlet valves were accessable from above in anticipation of lake debris getting past the filter. A lot of pumps have to have their pipework disconnected to gain valve access whereas with my design the pipework stays connected.

I'm pleased that you are progressing, I'll be very interested to know how you get on.

Ian.
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steamboatmodel

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Re: Flash steam plant control.
« Reply #208 on: August 23, 2011, 01:42:57 PM »

Hi Ian,
"I did design the pumps so that both the inlet and outlet valves were accessable from above in anticipation of lake debris getting past the filter. A lot of pumps have to have their pipework disconnected to gain valve access whereas with my design the pipework stays connected."
Could you post some on this design?
Regards,
Gerald.

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Xtian29

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Re: Flash steam plant control.
« Reply #209 on: August 23, 2011, 06:42:06 PM »

The pump design I am working to also has the valves accessible from the top without disconnecting pipes. Also, if the pipes are undone, the entire pump head is removable from the cylinder for quick replacement of the entire valve block. It has butyl "O" rings and a small oil cup for the piston Your pumps looked to be very compact, so I would also like to see drawings if they exist, especially your micro-Oldham couplings

If I make the pump as an exact half size copy I will get a 3/8"bore X 1" stroke. Do you think two pumps this slightly larger size will make sense given that my boat may need a bigger engine than the D10 at some point, and also perhaps a bigger boiler.   How often do find you need to run both pumps in unison during running, or was that used only during the early experimental phase? Does your software change which pump is the "master" so each pump sees the same number of hours use, just like the pilots had to do with the twin turbine engines in the Fairey "Gannet"?

A half size Ray Hasbrouck  No 8 engine would give a double acting .937"bore x 1" stroke V twin. I obviously cannot give any details of the drawings out as it would infringe the terms of purchase, but suffice to say, anyone half interested in engines would thoughroghly enjoy the 7 large sheets of impeccable drawings, which also come with a couple of colour photographs and full instructions. Should cost about $30, but check the net. Worth every penny.  I was so impressed I bought all his other plans just for the read.....

It is my intention to use standard brake pipe flared ends and joiners to connect the pipe in the monotube, and I was also going to make the ports of my pump and any other parts follow the designs found in a standard metric automotive brake system, IE the female sockets found in brake callipers. Is there any reason that this is a bad idea, as I am not familiar with either the imperial steam pipe fittings that model makers use, or their metric equivalents if they exist. All the cold water side could be plumbed in the plastic pipe and tiny brass olive seal system (SMC) cars use on their air suspension systems. Probably simpler to make and buy, plus a bit lighter! I will investigate.....

The fact you knackered a set of motor bearings vindicates the use of a decent set of support bearings for the pump rather than simply fixing a crank disk to the output shaft of the gearbox, which crossed my mind.

Any news on the publishing date yet? I'm going to have to pop down south to read your original "scribbles" at this rate!!  :}
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Xtian29

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Re: Flash steam plant control.
« Reply #210 on: August 29, 2011, 07:05:53 PM »

I have been looking for some way of having a mechanically driven water pump that is adjustable for flow, so I can use your control system but not have the need for powerful batteries.

I have just seen a pump in the book by K N Harris .... "Model stationary and marine steam engines" "second edition" fitted to a paddlewheel engine that may just fit the bill. It is on page 73, and further detailed on page 76. It could have it's stroke controlled via a servo.

http://www.fastonline.org/CD3WD_40/JF/424/19-423.pdf

It has a tiny air accumulator in the system to take out the hydraulic pulses that may exist in such things and it seems very compact, but my main interest is in the fact that I could prime the system mechanically or electrically,get the engine working and then switch over to  the engine driven pump.
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flashtwo

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Re: Flash steam plant control.
« Reply #211 on: August 30, 2011, 06:06:43 PM »

Hi,


No news on the publication date as yet.

My software is designed for a flow from a mechanical pump if I ever fit one. The engine speed would be used to calculated the feed from the mechanical pump and, as the mechanical pump's output increased, the electric pump would slow down or even stop automatically and vice-versa.

I still think an electric pump is very useful for starting and also caters for when the engine is required to accelerate and decelerate or even stop mid-lake under radio control. I suppose if your boat is manned you will be able to have additional controls like pump bypass.

Whats a micro-Oldham?

The motor bearing failure was actually at the non-drive end near the commutator. The pump has a ball-bearing block that absorbs all the trans-axial force of the ram so that the motor and its gearbox are just affected by the rotative forces. If you go back to the original post of this thread, you will see photos of the pumps.

Regarding matching the pump size to the engine size can be a bit of an experiment. I did note that the effective flow of my pumps under pressure, was about 86% of that expected from the calculations suppossibly caused by the valves not seating immediately and passing. Based on my experience, I'm getting 500RPM at 20psi with the D10 with a flow of about 75cc/min (using the 86% correction mentioned above) - this could be a good starting point.

Currently I don't require both pumps to run to achieve the 500RPM objective. If the pump battery is low in volts and the main pump can't maintain the flow, the second pump will come in automatically to compensate, but this is only if I've forgotten to charge the batteries.

On an earlier software version the computer actually logged the total number of strokes per pump per run and per season, with the intention of some "preventive" maintainance in replacing the ram "o"-ring and ball valves and, like you suggest, running the pumps evenly - this was getting a bit daft I thought. From an industry point of view though, one thing you don't want is your standby bit of plant to wear out the same time as the main plant. I've known some instances when some plant has only logged 20% running time and then had an overhaul, principly because you haven't the resources to overhaul every item at the same time. Different for aircraft I suppose!

Regarding the pipes being used. The flared pipes would be easier than using the pipe nipples and silver soldering them on. Beware that even this small pump of mine can deliver 300psi or more!


The drawings that I have done myself won't scan very well since the lines are very fine.

I have however produced a set of typed sequential instructions that I use in the workshop, since I have built a number of the pumps for experimenting with. I'm afraid the measurements are in metric and imperial, since the metal stock is in imperial and the workshop lathe and milling machine are in metric. The instructions are three pages long and may be more suitable as a personal message than in the open forum.

With this type of pump it is very easy to get air trapped inside so causing the pump to fail. To get around this problem stainless steel blanks are fitted just above the ball valves to take up the volume that the air would have used. The blanks can also be machined to limit the lift of the ball valves. The ball valves make a seal directly with the brass body without the need of "o"-rings.

The batteries are oversized for the job they do. I could use much smaller ones for a days steaming, but the larger batteries are also used as ballast.

Ian
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Xtian29

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Re: Flash steam plant control.
« Reply #212 on: August 30, 2011, 07:09:29 PM »

Hi Ian,

The drive couplings you have on your pumps are called "Oldham" couplings, unless I am mistaken, and you have made rather small and neat ones compared to the ones I can see are commercially available at RS. hence "micro Oldham"

I would gladly receive sequential instructions in a PM  :} It keeps me away from the telly....
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Xtian29

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Re: Flash steam plant control.
« Reply #213 on: November 25, 2011, 05:58:14 PM »

I was wondering if there is any update on the magazine article?

At the moment, I am tarting about with the peristaltic pumps I have designed and built for my brewery, and their performance leads me to wonder if they could be used as boiler feed pumps?

The tube I use in my brewery pumps is 15mm ID 3 mm wall soft silicone, and it would be a good idea to test what sort of pressures can be developed if the tube size is drastically reduced to say 1 or 2 mm ID, using the stuff that is used as model aircraft fuel line. The limit will be the burst pressure of the tube....

 I would not be at all surprised if the pressure these simple pumps can produce is quite high, and given that there are no pistons to lubricate, or valves to get blocked, and they are self priming, it may be worth investigating, but if they were indeed a viable option , surely someone would have done it by now!! Has anyone seen mention anywhere of such tests?

While building the brewery and making beer remains the highest priority, I will try to do some testing on a little pump sometime soon to see what pressure they will pump to!

Rog.
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Xtian29

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Re: Flash steam plant control.
« Reply #214 on: December 21, 2011, 04:51:06 PM »

It seems the magazine article will be in the February edition of engineering in miniature magazine. The Jan edition is out now, so start looking in a few weeks.
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derekwarner

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Re: Flash steam plant control.
« Reply #215 on: December 21, 2011, 08:15:02 PM »

This will be interesting Silverbrewer & it is good to see you have your priorities sorted  {-)

I tinkered with a minature peristaltic pumps 20 years ago....the burst pressure of the DUBRO silicone hose was never an issue....BUT keeing the tube attached to the pump ferrules was......

Even with DUBRO hose clamps........@ 15>20 PSI the slippery silicone tubing displaced it self off the ferrule....attempeted brass ferrules with sharper serations & they simply cut the tube ....

Keep us posted as the concept is great O0.....Derek
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Derek Warner

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Xtian29

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Re: Flash steam plant control.
« Reply #216 on: December 31, 2011, 07:10:53 PM »

It looks like the magazine article will be in the February edition of Engineering in miniature. The Jan. edition is out now, so mid Jan I suppose before it hits the shelves. I've ordered mine!!
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flashtwo

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Re: Flash steam plant control.
« Reply #217 on: January 08, 2012, 11:53:04 AM »

Hi,

"Vital Byte" and "Vital Thrust" will be exhibited at the annual London Model Engineering Exhibtion 20th to the 22nd January, Ally Pally. They will be on Stand S, "A Team Boatyard" alongside the 14ft HMS Daring and other large "items".

Looking forward to having a good old chin-wag.

Ian.
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flashtwo

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Re: Flash steam plant control.
« Reply #218 on: January 13, 2012, 08:59:36 PM »

Hi Mayhemers,

I've been investigating a problem that developed towards the end of September last year, but didn't have time to sort out.

Under hard steaming conditions with the gas valve fully open, Vital Byte was issuing flames from the top of the stack and the performance was deteriorating.

It was obvious that there was not enough combustion air to burn off all the fuel in within the boiler and I found that the stainless steel mesh scroll (see 2nd June 2011 posting) had developed deposits caused by combustion within its structure. Blowing through the mesh indicated a lot of flow resistance. I've replaced the scoll with a single layer mesh fixed across the top of the burner "bowl" and the combustion has much improved and you don't get that incomplete combustion smell either.

Today, I've been running under cold conditions of 5degC ambient and, despite using liquid fuel from the gas cylinder, found the performance was not up to scratch. With a 5degC cold full gas cylinder I found the gas pressure was at 2bar, but heating a full cylinder in warm water at 25degC the gas pressure went up to 4 bar and the performance was much better. Because the gas cylinder is inverted, the gas doesn't evaporate in the cylinder and hence the cylinder maintains its warmth much longer.

Roll on summer!

Ian.
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ooyah/2

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Re: Flash steam plant control.
« Reply #219 on: January 14, 2012, 11:52:17 AM »

Ian,
I experienced the same problem early on in my flash steam project.
I wanted to burn L.P.G  originally so I set up a roaring type burner and a copper gas tank with the burner firing into an A.A. Rayman design boiler.
The burner had a .025" jet and brass vaporiser coil on the end.
Before setting it up with the boiler I tested it just as a burner on the bench, heated the coil with a plumbers blow lamp, as I was burning liquid, coil getting a bit red, opened the liquid valve and away the burner went.
Great I thought it's burning well, after a few minutes all hell broke loose as the liquid came shooting out of the burner like a flame thrower and set the inside of the garage door on fire, quickly shut down the valve and  it was fortunate that it was a flash fire so no damage done, C.O. 2 extinguisher now installed at bench.

When installed in the test boiler it worked well but was inclined to flame and then would go into the cycle of cooling and losing pressure due to the size of the jet and the amount of liquid being drawn from the tank, heating the tank with a gentle application of the plumbers blow lamp increased the flame strength.
The burner seamed to work better when firing into the boiler space, possibly get more air sucked in, with the occasional flame out from the boiler exhaust.

Eventually I deduced that to get the power from the L.P.G. I would need a massive tank to supply the burner and stop it freezing, went on to paraffin.

Where does all this lead to your problem.
The out side temp of the tank is one, looking at your burner , is the tube too thick to allow it to glow hot and vaporize the liquid?
I found that the outside shell works better at .025" thk.

Do you still have so much tubing in your coil which could be preventing combustion ?
I found that the more space around the coil and the coils spaced about 1/4" apart was about correct, but then my aim was for power that your coil can't produce.

No doubt you will solve the problem when it gets a bit warmer.

Here is a pic of the experimental burner and A.A.Rayman boiler, burner is now fired by pressurized paraffin, this was an early experiment before my final  
triple burner.

Hope this helps.




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flashtwo

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Re: Flash steam plant control.
« Reply #220 on: January 24, 2012, 11:21:52 AM »

Hi Mayhemers,

I know one shouldn't advertise, but "Vital Byte" has left me a personal message (something about a certain magazine article I assume):-

Ian
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flashtwo

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Re: Flash steam plant control.
« Reply #221 on: January 24, 2012, 12:03:09 PM »

Hi Mayhemers,

I’ve investigated the reduced performance a bit more and have noted that, with the gas control valve fully open, the burner noise was much less than expected and the outlet pipe from the gas control valve was frosting up badly. This indicated a partial blockage in the gas valve causing a throttling effect which made the assembly act like a refrigerator.

Sure enough, on dismantling the valve it was blocked. I cleaned it out and normal service was resumed.

At the London Model Engineering Exhibition last weekend, where “Vital Byte” was on display, I discussed this problem with a couple of visitors. One chap had had a similar problem with his gas fired steam loco and found that a waxy substance from the gas cylinder had caused the blockage. He had fitted a “coffee paper” filter (the cigarette filter he tried caused problems with its fibres)  and this stopped the valves blocking. With the gas cylinder inverted perhaps this encourages deposits to be expelled from the cylinder.

Another good tip from the same guy (16mm gauge loco enthusiast) was regarding the burner mesh. He is using a nichrome mesh instead of stainless, since it degrades far less with the heat. He makes his own mesh from wire using a pin board.

Another visitor had built his own manned steam canoe incorporating a monotube boiler. He thought my system was a bit complicated, but I did remind him that I wasn’t onboard to adjust things unlike himself.

Anyway, there was lots of interest in “Vital Byte” with very much welcomed advice from visitors and other exhibitors alike.

My favourite exhibit was Jack Snary’s (and expert grandson) “Royal Spithead Review” with it hundreds of miniature ships detailing naval history from Ancient Egyptian times up to the present.

For the next part of the project, I will be rebuilding the timing linkages on the D10 engine, since they are very worn and sloppy.

Ian
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TurboTyne

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Re: Flash steam plant control.
« Reply #222 on: January 24, 2012, 12:39:47 PM »

Hi Ian

I've just read your excellent article in EiM. I think it is very interesting and I look forward to the next part. The trouble you take to explain the principles of computerised control to the wider audience reminds me how much I have learnt since I last pestered you with questions - which was over a year ago now. Before I saw your blog about Vital Byte I had not heard of PIC devices at all. Your advice was not wasted because, since then I've learnt a lot about PIC programming. So far I have constructed a gas burner and a needle-type gas valve operated by a stepper motor which is controlled by a PIC. This PIC receives instructions from the master temperature monitoring PIC via the I2C bus. The latter master PIC also sends data to a display PIC and to a serial EEPROM which can be removed and (I hope) have it's data read into a PC via a cheap USB-I2C interface that I've bought. So I am getting near to having a temperature controlled gas valve - but a lot more work will be needed before I know if all this effort will give a workable boiler control system.  It's been great fun learning all this - thankyou for showing me the light.

Regards,  Mike
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flashtwo

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Re: Flash steam plant control.
« Reply #223 on: January 24, 2012, 02:24:33 PM »

Hi Mike,

I think its great that you've made such progress - I shall be asking for your advice very soon, especially about I2C.

How do the stepper motors compare with the ordinary radio control servos - do you have to set a mechanical starting point of reference, or have they developed since I last used them many years ago?

Have you used anything like picAXE boards?

Will you be using your burner with a conventional boiler or a monotube?

Thanks you your EiM comment - any feedback will be appreicated.

Ian.
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TurboTyne

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Re: Flash steam plant control.
« Reply #224 on: January 24, 2012, 08:11:07 PM »

Hi Ian

Always happy to chat but I doubt I could add much to your knowledge.
I have never used (or even seen) a radio control servo. My lack of familiarity with them is one reason I chose to go down the route I have. My hobby activities have been in model engineering etc and I felt inclined to have a go at making a valve from scratch. Also, I've long wanted to have a go at trying to use a stepper motor - for something or other, mainly so I'd properly understand how they function. This was undoubtedly not the most efficient way forward to make a boiler control system and for that I should have followed more closely what you have done with servos etc. My efforts have taken much time and the valve is not exactly compact. The stepper (taken from an old ink-jet printer) does, as you say, lack any points of reference. I've attached a couple of photos which show the arrangement  I came up with. Movement is by a screw which drives a block attached to a lever. The 40 tpi thread and the 5:1 lever combine to give a very fine adjustment of the valve rod such that about 10 turns, each with 48 steps, are needed to fully open the valve. The limits to movement of the screw-block are by the optical sensors - the black blocks with a central slot. As I'm sure you recognise, the thin metal sheet attached to the screw-block goes into the gap in the sensor and blocks the light beam. I am new to all this and was amazed at the accuracy of these particular devices. I estimate the electrical output goes from full on to full off with just 2 or 3 thou movement of the block. Of course the sensors connect to pins on the PIC (16F818). The programme includes a few lines of code which ensure that, when the direction of the motor is reversed, a few extra steps to the movement are inserted so as to take up the slack in the mechanism.

No, I did not use the picAXE items - I just ordered PIC chips from Farnell. Another thing thats amazed me is the amount of free stuff they provide. I use their free MP LAB IDE programme for all my programming in conjunction with a Pickit3 programmer.
 
RE: the boiler. I shall initially be messing about with a monotube boiler coil that I actually wound over 40 years ago - but never used. I had dreams of making a flash-steam hydroplane, but now I am aiming for something more sedate - but definitely monotube.

Mike




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