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[DBS88]

The renovation of the Tug is still ongoing and these posts have not yet caught up to the current position, which is as follows. The steam plant is installed along with the electronics. Before installation the steam plant was run on the bench numerous times to test various items and get the set up sorted. The complete model has also been run on the lake now half a dozen times in the last fortnight, the last two runs were endurance runs, to see how long it could run for without being returned to the bank. At this stage I won't spoil the story, but what I can confirm is that it has run without issue, and the reason for mentioning it at this point in the build log is to confirm that any bubbles in the sight glass have not caused a problem, it appears the debouncing technology works as no false alarms have been triggered. If the bubble didn't clear and the sensor continued to see no water, it would shut the gas down to a pilot light and a large high intensity LED would turn on to warn the user that the boat should be returned to the bank for further investigation. Here is a photo of the tug during this weeks endurance runs.

[rhavrane]

Bonjour,
I think I will test Denes products and besides this, what a beautiful bow wave which proves the efficiency of this also beautiful boat 

[SteamboatPhil]

Nice one Dave 

[DBS88]

With regard to the sight glass sensors, there is something to remember - not all sight glasses are 5mm in dia. The boiler that I have ordered has an 8mm sight glass, another boiler I use has a 3/16 inch sight glass, so if you are going to use electronic boiler controls that use an optical sensor fitted to the sight glass, the correct size is important. Here is a photo of the sensor for the 3/16, the 5mm and the one for my new boiler with the 8mm sight glass. If its not the correct size either it will fall down the sight glass or else you won't get it on the sight glass. This is an example of the feedback that I have given to Dénes and also an example of how he has responded to supply sensors to meet the need.

[DBS88]

As mentioned in an earlier post, I had been offered a second complete Cheddar Proteus Boiler, Engine and ABC, so I agreed a price and waited for it to arrive in the post. Now my thinking was that my Black Swan Sloop needed two engines and this purchase would mean that I had a pair of Proteus engines that could be used for that project. When the parcel arrived I looked it over and put it back in the box whilst I continued with other projects and I didn't give it a thought til recently. I mention this now, because its this engine and boiler that are in the Bustler Tug, and the eagle eyed amongst you may later, have spotted that it is a different steam plant to the one we started testing.


I knew this steam plant had been used for only a few hours, less than 10 so was confident that it was all ok.

[DBS88]

When I got round to testing the steam plant I checked over the ABC, oiled the engine and filled the boiler and fired it up, the pressure was raised quickly and at 30 psi I opened the steam valve to let steam through to the engine. With the first Proteus engine I found it was best to get it moving at a low pressure, since at higher pressures it was hard to get started if it got a hydraulic lock, so warming it early and turning the flywheel by hand seemed to help. However with this engine I found it to be very stiff and difficult to turn which surprised me. The pressure rose and after 45 psi the engine started to turn over and began to run, but no where near as freely as the first engine. I assumed that it was tight and needed running in so put some more oil on the moving parts and left it to run for a few minutes.


I checked the engine over and turned the flywheel by hand, the flywheel felt warm to the touch, so I looked closer and found that the flywheel was rubbing on the eccentric strap for the water pump. I undid the flywheel and moved it further along the crankshaft, immediately the engine turned more freely. Another look revealed that the pumps eccentric was also pushed to far on to the crank, so this too was slacked off and moved so that it was is line with the pump. I also realised that the pipe for filling the boiler was connected to the wrong outlet on the by pass valve. So I took the pipe off and disassembled and checked the by pass valve before reassembling it all correctly. Now the previous owner had said that the engine needed 45 psi to get it going and also that they had never really got the water bypass working satisfactorily -


With these things put right I tested the steam plant again, it was like a different engine, it started easily, it revved freely, and the pump filled the boiler as it should, the sight glass sensor worked, so all was good.

[KNO3]

Very good that you could easily sort the issues with the steam plant. With second hand engines you can never know if previous owners handled and assembled them correctly, it is good to check them thoroughly before running.

[DBS88]

Thank you, I too am glad it was an easy fix. However, whilst I had run the steam plant on the bench to check it all operated, to make sure that the water valve and the gas valve opened and closed as they should and that water went into the boiler, and that the electronics worked as they should. What I had not done was let the steam plant run for a longer duration to see how well the water level was maintained in the boiler, if I had I would have picked up on another problem and would have saved myself several hours of frustration as I tried to get the flow of water into the boiler balanced.


The issue was with the servo controlled water valve, I struggled to get it adjusted correctly, either it would let too much water into the boiler - that is, it was not opened far enough so that when no water should be going into the boiler, it still did, or at the other extreme, not enough water would enter the boiler - the valve was not closing sufficiently to allow enough of the pumped water to enter the boiler. This then, as I was later to discover, was the main cause of the problem that the previous owner had mentioned. The water bypass and boiler filling system worked perfectly on the other Proteus steam plant and I had not experienced any issues with its set up, so the difficulties I would later experience during the installation of this steam plant left me puzzled and frustrated.

[KNO3]

Sounds like the bypass valve lever arm not moving enough? How did you solve this problem?

[KBIO]

Very tricky to adjust the flow rate with a by-pass valve.
Also the lightest friction somewhere on the engine takes a lot of the power off!
I've been through all this and I didn't success every time but I am quiet sure that your common sense will solve it all !
Very interesting and optimist to follow your progress toward the end. 
Cheers !

[KNO3]

In this case the bypass valve (controlled via servo by the Cheddar ABC system) does not need fine adjustment of the flow. It is either turned on or off by the system, according to the water level in the boiler. What I understood from David is that the bypass valve did not open and close properly, probably because the servo was not adjusted to move the lever enough.

[Dainesh]

Hi,


I think here is the chance to advertise my GCU  [size=78%] [/size]

It is not just ON and OFF on the gas control servo it has interim positions too, so the theory is that the unit is balancing the gas level according to the necessary boiler pressure (between pilot and totally open position), and it is able to keep the boiler pressure on the same level all the time.
I think this is better for the gas tank because it is not losing a large amount off gas quickly and the pressure doesn't drop down and it is not cooling down so much...


The main thing it is able to manage the gas burner better than all of those systems which are just switching ON and OFF.


So sorry for this postI just would like to highlight that there is a solution for some of the issues.

[DBS88]

Re the bypass valve, you are right, it was an issue of mechanical advantage. Because the steam plant had been previously installed in a boat and had run for around 45 mins, I thought the valve was ok so couldn't initially understand what the problem was. I spent most of a morning setting up the valve and had got it just about right, I made a final adjustment then went to test it again, only to find that the servo had died. I was less than happy, so replaced the servo and in doing so realised that the servo arm was shorter than the valve arm, so the valve was not moving a full 90 degrees - a real rookie error that I should have spotted.
Here are photos of the original set up and then the new servo and longer servo arm. As soon as the replacement  was installed, the set up was easy and it it all worked properly first time. So it was definitely the length of the servo arm that was the issue.

[DBS88]

Work has been ongoing with this project since before Christmas, its involved a lot of trials and testing, its been a great learning experience and its been the reason for not making progress with my Torpedo Boat Destroyer HMS Daring. All the elements of this project came together and picked up real speed in March, so I am trying to catch you up to date and provide you with as much history and information as possible on the way.
So it may be help the conversation to have a look forward at some of the areas that will be covered over the coming days, they include, in no particular order:

• temperature/pressure sensors
• preparing the inside of the hull for the steam plant
• installing the steam plant
• testing the Dénes Automatic Boiler Controls
• testing a Gas Control Unit
• testing an engine control unit
• testing electric pumps
• Installing onboard water tanks
• Why this project was undertaken

[DBS88]

Since we have been discussing the water supply to the boiler, now might be a good time to look at pumps. Some of what follows is a bit of a jump ahead in time, its not strictly in chronological order.
The bench testing of the steam plant has shown that the proteus engine driven pump delivers more than enough water to meet the steam needs of the engine, which is great news. However, I am also keen to find out more about electric pumps as an option, whilst I may use the proteus for the Black Swan, the engine I favour does not have a pump, so whilst I was testing the Dénes Automatic Boiler Controls on the Proteus I took the opportunity to try one of its additional features. When the sight glass sensor detects a low water situation, the Dénes ABC has the option to be set up so that it powers an electric pump, and when the new water level is achieved to turn off the pump, so its not running all the time, not only does it do this, it has a soft start and finish so that the pump starts slowly and then builds up speed and when the level is achieved it gently slows down again, a nice touch. Here is a link to a video of the ABC running an electric pump. [size=78%]https://youtube.com/shorts/BcM0kFfbG6o[/size]


In the box of bits I have collected for the Black Swan project I had two of the Chinese electric pumps ready for the project, the bore is 6mm and the stroke 5mm giving 0.14 cubic cm of water per stroke. My first surprise was how slowly the pump turned with the 5v output from the ABC, 30 rpm, which gives 1/4 litre of water per hour. My second surprise was when I tested the second pump, it turned at 60 rpm?, which gives 1/2 litre of water per hour, better but not enough to keep up with demand.


So if you buy one these pumps you need to know which you are getting, mine are not marked so I had no way of telling what rpm they did. The above capacities may well be enough for your set up, but what I learned was that you do need to know how much steam/water your engine boiler combination uses so that you size the pump correctly.Research revealed that I could buy one of the motors that drives the pump complete with the reduction gearbox for about £5, so I selected one that gave me 280 rpm to produce 2.3 litres per hour, which would keep up with and exceed my predicted demand.[size=78%] Here is a link to a video of the replacement electric motor at 280 rpm https://youtube.com/shorts/ce9wC4rbnn8?feature=share


I also came across a very neat unit from Regner, now my German is not good and I had not found the translate button on my computer, but despite this managed to order one which duly arrived. Its bore is 10mm with a 5 mm stroke to give 1/2 a litre per hour, which would extend running times but not keep up with the engines demands, so no good with this engine and boiler combination when used with automatic boiler controls. Here is a link to a video of the Regner pump unit running.[/size][size=78%]https://youtube.com/shorts/9I71eFq4TOw[/size]

[derekwarner]

Dave......I found this in the string from your video....it confirms the issue or challenge we all experience with conventional R/C servos & float of the function.......there may be an alternate drive function in the American Robotics WEB site

https://youtu.be/rHNmjyRUXGw


Derek

[KNO3]

Very interesting report on the electrically driven pumps. I wonder if the servo used by the Regner pump could also be made to run faster?

[DBS88]

Derek, thank you, I am not great with the rc stuff, so didn't really understand, I would not wish to miss a learning opportunity so please could you re word your reply in another way so that I might understand it properly, thank you.


Re the Regner pump, firstly there are two versions of this pump, one with servo electronics and one without, I purchased the one with servo electronics. With regard to speeding it up, what I have found during conversation with a fellow Mayhem member is that, the servo electronics allow you to regulate  the speed of the pump, so at max speed this pump is rated to deliver 570ml of water per hour or just over 1/2 a litre. The servo electronics allow you to set the speed of the pump anywhere from 0 rpm to max rpm, so it does not appear that you can increase the speed but you can slow it down or regulate it. Here is a link to a video showing the transmitter being used to control the pumps speed.  [size=78%]https://youtu.be/y2OMzYdCMPI[/size]

With the electric pumps, its possible to increase their speed by increasing the voltage, mine were running from the  5v output from the Dénes Automatic Boiler Control unit. Supplying an increased voltage from another source would increase the pumps speed, I believe these pump units will take upto 12v, so more than doubling the outputs previously mentioned. That does bring with it a world of pain with different voltages for different items of equipment, which whilst possible, it is something I would like to avoid if possible.

[JimG]

I also came across a very neat unit from Regner, now my German is not good and I had not found the translate button on my computer, but despite this managed to order one which duly arrived. Its bore is 10mm with a 5 mm stroke to give 1/2 a litre per hour, which would extend running times but not keep up with the engines demands, so no good with this engine and boiler combination when used with automatic boiler controls. Here is a link to a video of the Regner pump unit running.[size=78%]https://youtube.com/shorts/9I71eFq4TOw[/size]

If you go to Google Translate and paste in the URL of the German website it will produce an english translation of the whole page. Its also fully working so any links and forms on the page will still work. The translation is generally OK but technical german is difficult to translate and may not translate well or at all.
Jim

[derekwarner]

Dave....getting back to this video, irrespective of Brand I have used, each servo appears to exhibit a mushy or rubbery band at the set point which when a physical force is applied to the servo or more the driven effort, you can hear the feedback trying to return or establish that set point


The other consideration could be an adjustable Turnbuckle in the rod between the servo & the mating part, so to use the turnbuckle micro-adjustment over the main adjustment at either end of the adjustment rod


One of our Members 'Bernhard' for Denmark, had used and demonstrated both the Regner & the Microcosm boiler feed pumps, although without the extent of comment which you are providing [thankyou]


Like you, I also had 2 of the Microcosm P? pumps, the first speed reducer was like a VW engine & totally unacceptable. Jin offered to replace it FOC, but the postage return to China was absolutely prohibitive. I replaced both speed reducer [edit - motors] with an off the shelf Australian 22mm OD unit, however the tandem setup as below was a disaster with the speed of closure of the check valves as such, the water was just going around in circles


You appear to have the newer P5 pump with encapsulated o-rings under the banjo fittings......I have the earlier version with white Nylon seals, which were useless    so have replaced with RED fiber sealing washers...the newer P5 pumps also appear to have gone away from ball & seat check valve to a minature brass poppet + even smaller section o-ring.........I am not sure of the longevity of the minuscule section o-ring hammering shut a few hundred times per minute?...where I suspect the pressure [even 2 or 3 Bar] will be sufficient to cause eventual metal to metal contact however without security of sealing


I  have since ordered larger speed reducer 25mm OD & this has higher low speed [130 RPM] torque. The extended output shaft will be for the pump + a second function + the outboard bearing 


Looking forward to your further posts on this matter


Derek

[KNO3]

Hi Derek, why do you need two pumps on your steam plant?

[derekwarner]

Evening Calan.......it was a trial concept only, however like a lot of my thoughts, didn't quite function because of the inability of the opposite check valve within the pump bodies to seal the small volume of pressurised water from the opposite pump, quickly enough & hence pressure decay, before the discharge line check valve      


As an alternate to the dual electric system, I mounted the second P? pump as a direct vertical eccetric drive off the 4mm crankshaft of the Saito Y2DR.......the problem with this was lubrication and steam oil gathered at the pump plunger shaft & began ingestion to the water system [edit - and the check valves failed to reseat - the pump body axis must be in the vertical plane]

Derek

[DBS88]

For some time the Dénes ABC sat in my Black Swan box of bits, untested. While the first Proteus steam plant was on the bench, after having replaced its faulty Cheddar sight glass sensor, I let Dénes know that the new sensor worked fine and he asked how I was getting on with the ABC, so sheepishly, I had to confess that I had not yet tried it. His query spurred me into action and I removed the Cheddar ABC and wired up the Dénes ABC. Here is a link to a video of the Dénes ABC going through its start up sequence. What you will see is me connecting a battery, and 11.2v Lipo battery which is fine because the unit has protections from over voltage built into it, it actually operates at 5v and has a low voltage protection/safe mode as well. Next it checks the water in the header tank, if none, nothing happens, once that is satisfied, it checks the water level in the boiler, once that is satisfied, the start sequence continues with a test of both the water and the gas servos, it then is ready with the gas servo open. https://youtu.be/WR7lD9Q3R50

[derekwarner]

Dave....


Hope we are not getting too far off track, but here is a video    of Bernhards Regner boiler feed pump from 2011 ...it needs 27 seconds to open  but then confirms the squealed cat sound  when pumping under pressure


http://www.youtube.com/watch?v=ueqAWDNTO5k


Derek

[DBS88]

Derek, thank you, that is a lovely steam launch Bernard has created, its always helpful to see these models working since it furthers our discussions and helps our understanding. The Cheddar Puffin has the same bore and stroke as the Cheddar Proteus at 7/16 inch bore and 7/16 inch stroke, both are double acting, so consume similar amounts of steam, with the slide valve Proteus likely to be the more efficient of the two. What we see from the video is the Regner pump tanking its water from the paddling pool and we see the pump operating at what appears to be its max rpm, which is all good. The system works and extends the run time of the boiler for what is a fairly steam hungry engine. This confirms for us our early conclusion that the Regner pump is a good pump, but its capacity is not able to meet the demands of the boiler and engine combination, so while it extends the run time, the water level in the boiler will continue to fall.


This is important, since when using the automatic boiler controls, we need a pump that will meet and exceed the boiler and engines demands, so that the water level rises in the boiler while the engine is running. If the water level is falling we need to know. My First Steam Tug has the Proteus Boiler supplying steam to two Cheddar Puffins and has the Cheddar ABC which all works fine. However I will confess to potentially serious event with it. The model had just passed its annual steam test, it was running fine, I always check that the pumps are pumping water. Anyway the model was running round the lake on a frosty morning looking fabulous, then it slowed down, so I tried to return it to the bank, but failed. I watched it drift slowly, then became alarmed as dark smoke appeared from the funnel. Now the experienced steamers amongst you have guessed that the boiler had run dry and now the mahogany cladding to the boiler was becoming hot. In this situation the Cheddar ABC turns the gas down to a pilot light, so there was not a full flame burning on an empty boiler. Here is a photo of the steam plant in the tug and a link to a video of the steam plant working [size=78%]https://youtu.be/gRxDjKCv790[/size]


I mention this because while testing the Dénes ABC I relayed this event to Dénes, he listened and and agreed it would be a good idea to modify his ABC units. The modification means in the event that the sight glass sensor detects a low water situation it opens the water valve to let water into the boiler or it turns on the electric pump as it did before, but now the monitors the situation, and if the water water level does not return above the sight glass within a certain time the system goes into alarm, shutting down to pilot light and illuminating the high intensity red warning LED so that the operator knows to return the model to the bank in good time to investigate the cause of the alarm. This then is an improvement over the Cheddar ABC.