Here is a list of all the postings Werner Schleidt has made in our forums. Click on a thread name to jump to the thread.
|Thread: How do you stop brass tarnishing|
the shiny surface of the brass is very difficult to hold over the year during the driving session. At the moment I had my Fire King disassambled for the transport from the garage to the basement. So I give all the steam parts a polishing and a control of function. At the boiler there are many pipes and things installed, it is not feasable to polish there over the year. In winter I take all off and then i can polish it. And it is a hard job to get the dirt of espacially in the area of the chimney. By starting of the cold engine and if i am not patient enough there is condensend water with oil comming out of the chimney . This oil burn in in the cover and this is hard to remove.
From me i accept to polish ,because I have fun to drive with the engine.
By the way your fire engine looks very good!
|Thread: Wanted - Brass tube bending|
I think you have to fill it with fine sand and close the ends. It should be on the bended end for 10 centimeters longer to span it. And then you can bend it.
|Thread: GPS as a low-speed Speedometer|
I made tests with my android phone and rfo basic. I can record the readings and all looks good if i drive in my car.
But where i want to use it with my road steamer at slow speeds. I have increments of 1.6 Km/h and that is much worster then a cycle speedometer. On our road are some high trees and there the gps readings are frozen in. It is very useful to record the track profile but not accurate for low speeds. If you want accuracy you have to have a higher update rate and differential gps. And these are not cheap components. The idea with the accelerometers need exact leveling of them, like in a quadrocopter setup. If you use a handheld device,if it is not leveled , that fails by integrating partly the earth acceleration.
For me the only stable solution is a cycle speedometer coupled by wheel impulse.
|Thread: electronic cylinder indication|
In the small box is an arduino nano with the connector bank for the eight analog channels , the bluetooth modul with 115 Kbaud and the power supply based on old laptop cells. The power supply is able to work with eight sensors for two to three hours.
On the laptop screen there is a test measurement of 30 secs to see.
In these many curves is the start , some braking with load and the stop to see. This is a kind of overall info as you can see it during measuring .After the stop the data have to be stored. I can measure several tests and store them with usefull short names. After a stored measurement i can reload it and look in the time frame for interesting parts. In the time frame i can look if there are two to three similar curves and with the start and end point I can plot them then in a xy diagram. Is this in running condition on the track i calculate the average pressure and the rpm of the engine. With the piston size , travel ,rpm and average pressure the power in this cylinder chamber can be calculated. This is possible but it is difficult to run the engine under full load. I use the system as a tool to see the begin of steam come in and the shape of the curve. So i can adjust the valve gear. I do not like try and error methods as i made it befor i have this system.
My experience at the moment is, it work good, gives good results , but the software and the procedure how to measure need some fine tunning for more comfortable use in the field. And one thing is at the moment clear, i see it as i measure Jürgens engine. All visitors are exited to see the result immediatly and this is only possible to see in the overview as it is in the picture above. I have to add in the software during measuring some markers for the constant driving or something like that.
Over the winter I think i can make some fine tunnig based on the experience i had now.
Edited By Werner Schleidt on 16/09/2021 14:11:42
The displacement sensor or the piston travel sensor is more tricky. I want to have a sensor who is on small and bigger engines possible to install. I had an incremental angle sensor this is very accurate but it have to be attached to the axle or flywheel and that is not so easy without changes at the model or object. I get by chance a very fine LVDT displacement sensors with a carrier amplifier and inbuilt electronic. To meassure 100 mm the sensor is about 300 mm long. This is difficult to mount. So i came to the results that the sensor mechanism with a rope like in the old indicators is very favourable. So i thought about about how i can build a sensor. In my former job i know rope displacement sensors based on a rope a return spring mechanism and a rope drum and a potentiometer. This parts are very expensiv , the range is from 500 to 1000 €
So i construct my own. The base is a multiturn wire potentiometer with 5 Kohm , a drum which is coupled with the potentiometer axis and a return spring i got from a identicard jo jo. This were my parts which play together to operate the rope sensor. My modelplane colleague Herbert sponsored me with thin multiwire control line rope.
It was very tricky to bring all parts together and after the first one i made two others all in a range of max 300 mm. I tested them in comparison to my digital gauge at the milling machine. The measurements were very repeatable and with a good accuracy. I added a small amplifier with a filter for cutting noise and with a level shifter for easy zero shift adjustment. The span was precalibrated at the amplifier and a fine calibration can be made by software. All sensors have a unique calibration file, but the rope sensor are very similar.
To give you an idea from my sensor
The spring is in the frontside of the drum . In the front cover of the housing there is a screw which is the spanner for the spring. The tricky part is adding the rope winding by winding in the right direction and spanning the clock spring and setting the potentiometer at the correct position. This is a four hand job, but with several try's it worked good. The amplifier ist then attached to the potentiometer and then it was added some heatshrink tube. Then the parameter and calibration was measured and marked at the sensor.
In the next picture it is adapted to my loco for measurement.
The pressure sensor is connected to the cylinder cover. The rope sensor is mounted with some improvisation with clamps and wooden bars at the front. The rope is connected to the crosshead by a chain and a adapting screw. The white PA part allows clamping of the sensor and some adjustment.
Edited By Werner Schleidt on 15/09/2021 18:03:05
Hello all and many thanks for your interest!
I want to add more information about the sensors.
The pressure sensors are china made ones in a stainless steel housing with diaphragma and strain gage amplifier and ready calibrated. They are made for 5 V excitation and have a range from 0.5 volt to 4.5 Volt. I compared them with a normal Pressure gauge with good results. For my software i marked them with the parameters i have to add in the software for the correct span and zero adjustment.
I made adapter from 1/8 BSP and 1/4 pipe thread to M6*0.75 mm for easy use with my model applications. The sensor is very cheap ( < 20 &euro for the quality and good for field measurements. I found no noticeable drift.
The connectors had been changed to rc model type ones they are simple and cheap. If they were pulled out by accident there is no damage possible. I secure them with tape and add numbers or a discription to know hwere they are installed.
I know that for internal combustion engines piezo electric pressure transducers were used. One special brand is Kistler from Swiss, they have a good knowledge and reputation. But there parts are extremly expensiv.
For this job the china made transducer are in the range of 20 € and this is no problem and they are precise enough.
My homebrew software is able to measure the rpm of the engine and the average pressure during running. And with this i am able to calculate the engine power. For valve setup investigations this is not useful, because normally we run the engine not under full power there is normally a throttle valve in front of the cylinder. The Garret of Jürgen is extremly powerfull there is no easy way to brake the engine to get a full power diagram.
And with my small 5 inch locomotives it is the same.I had to use a brake locomotive it is the same as they do it in full size. I tried to make a test on track with cylinder indicated power in comparison to Power at the dynamometer and speed of the wagon. This gave partly some good and some strange results and i found that our track is not in horizontal level. I have to use my electric locomotive as a brake loco to charge the battery.
But then came winter and corona and so all investigations were on hold. I have more ideas then capacity to do all.
Electronic cylinder indication is a good tool for fine tunnig the valve setting and this is the main function i use. And it is much better then the try and error method i use before. And i am very astonished with which small changes a very different driving behaviour is possible.
we made another meeting with our steam friends. Jürgens Garret Traction engine have now a correct valve setting , based by the investigation of the electronic cylinder indication. On the end of the video there are two sequences were the engine is set to a very slow rpm . Now the engine have a fine driving behaiour and the coal and water consumption is remarkabel less than before.
Have fun with the video.
|Thread: Dynamic Balancing a BLDC motor rotor.|
thanks for the explanation!. As you discribed it I had the idea how it can work.
a very nice test rig and test method! Perhaps i overlook it , how do you measure the angle? I do not noticed a sensor. There is a rpm sensor in the text, do you calculate over one period and calculate from one rpm over time of one revolution the angle?
|Thread: from a 3.5 inch Gezina to 5 inch tramway Plettenberg locomotive|
I had some time to make driving tests at our club track .The Plettenberg tramway locomotive is my smallest locomotive i have,but she is powerful enough to drive with two adults. The weight of her is about 27 Kg. And she is equiped with injector and a steam pump and a automatic helping blower valve.
I forgot that i made a special coal shovel for her and so it was a little bit fiddling to get the coal in the small fire hole. But with some experience this was not a problem. It was a very enjoying day to drive her. I made the video by my own and so it was a little bit tricky to record myself driving.
I think the video give a good overview of the driving behaviour of this smal locomotive. I am ver astonished how good this small oiler behaves . The cylinder and boiler was from a former 3,5 inch locomotive and was then converted to the Plettenberg.
I found a video from the original which is located by the Deutsche Eisenbahn Verein in Bruchhausen Vilsen in northern Germany. It is a nice video with german explanations , but the pictures are in international language.
|Thread: Java 0-4-2 O+K De Maas Sugar Mill Locomotive|
I made some test driving at our local club track. The video takes have been collected by my mobile phone therefore it is a bit shaky.
Till 2.5 minutes it was the first test session .In this session i found that my oil pump deliver to less oil and after some kilometers the regulater shaft was blocked . The investigation showed that i had a to tight fit. The oil pump had not a good machined ball seat. And our track is more like a narrow gauge field track and so the rear axle had not enough spring travel to have agood contact to the rails. I added longer springs and now i have +- 7 mm spring travel and a good support on the track. Additional i found that the teflon piston rings are not so good steam thight. I made new ones from solid teflon bar and slice them with a sharp knife in a 30° angle with an o-ring for static tightness. This was a perfect rework. The coal and water consumption was drasticly reduced and the engine had lot of power to polish the rails if i open the steam regulator to fast. This starts in the video after 3 minutes.
Now it was a fun to drive.
|Thread: electronic cylinder indication|
K_weg is the short form for Kolben Weg or better to understand piston travel. Your deduction was correct.
I try to make it so understandable as possible, but I see there is room for improvement. The same I learnt from my colleagues, at our driving area , they see all ,got explanations, but with the video and additional explanations they understand it complete.
I know it is diffcult and I worked in my profession with complex professional equipment. So something is for me known and I had to explain it for others ,who see this the first time.
If i study the old books it is very remarkable what was known and in this times forgotten now.
Edited By Werner Schleidt on 08/08/2021 10:46:12
a few words to my fire king. It is roughly planned to make indicator measurements too. But this have not so a high priority.
The steam engine had a remarkable improvement of the boiler and fire performance with the added steel stripes in the fire tube which is normally for the superheater pipe. Many thanks to Johannes, known as Yorkshire Man, he gave me the hint in a german forum. So i gave this idea a go and test it at my fire king boiler.
This stripes hang in the middle wide tube of the boiler. This stripes force the exhaust around this stripes and add some resistance for slowing down the gas velocity. So the exhaust gas have more time to add heat to the boiler.
The change was remarkable. I could drive after this with continous blowing safety valves and the fire burns much better. There was only like black sand in the smoke chamber. Before there were much more bigger unburned coal parts and sparks. I changed then the exhaust nozzle to a wider bore. This gave the steam engine less back pressure and so the RPM and power increased. The fire burns a litlle bit worster ,but much better then before I made all this changes. If i drive continously and do not forgot to add coal regulary , I can drive permanent with a pressure short for blowing of. I can control the pressure by adding water or not.
Here is a photo with the setup and the changed exhaust nozzle after 11 Km of driving.
And here is the clinker after this ride
This was a big improvement.
I made measurements with a thermocouple to measure the exhaust temperature and it was clear to see that the fire burns much better.
More information in the thread Merryweather Fire King self propelled
Here is the diagram with the principal indicator diagrams.
It is from the Handbook on steam engines from Haeder and Powles 1902.
Thanks to Vic who sponsored me with informations and web links!
This is taken from the side 383
The left curve number four with late admission fits to the kind of the measured curves and number two throttlling. For the power of the engine we had during the measurement to less load . Normally the engine have to pull a wagon with some adults as load.
I try to explain what you want to know. I made a picture of Juergens valve gear and there is to see that the valve steam channels are casted. The blue side movement from chimney to gear or the rhs in the diagram is not very accurate. The shape is not with straight cut as it is achieveable if it is milled.
For my opinion is this the reason in combination with some marks on the valve running surface that there is in this area the valve is not perfect steam thight.
The steam channel on the gear side is more accurate and straight. But in the picture it is not very good to see.
And there are many marks on the surface too.
When I look in old books i found that from 90 to 100 mm piston displacement the blue curve comes up and the reason is that the steam port to the chimney is closed and there is some compression. Therefore at about 100 mm there is then steam comming in and this cause in a slope, because steam pressure is lower then the compression pressure at this moment of opening the valve. To make this perfect the valve have to be a litlle bit machined in the inside to allow the steam to come earlier to the chimney. If green where mirrored as a blue curve this will be better.
If we look to the curve in the old book there is an example which is discribed with too late admission.
Juergen made the excenter settings with not very good explanations in the plan, as he told me. He had to interpretate some dimensions. And it was clear he had to decide to screw down the excenter after his measured dimensions. I think the result, after this possibility of possible mistakes, is very good.
Juergen want not to change anything in the beginning, he was satisfied with what he had achieved. As I show him which i achieved with my little loco Plettenberg with the first tests of the electronic cylinder indication setup, he gave me a try. I made then some attachements for the rope displacement sensor and the electronic.
The first base measurements were made with lot of improvisation during standing without load. This was not good. The best behaviour for measurements is slow running ~ 120 -200 RPM and under load. As you see in the diagram, there is a very low steam pressure ~ 1 bar during driving in the cylinder.
The pressure sensors are connected with tubes, because he had no possibility to screw the sensor pipes to the cylinder. But in the other hand it is good to see that the measurement setup is in function with this circumstances.
Here is a closer view of the sensor attachment. For me it is a little bit difficult ,because i make all pictures, video, computer, measurement and calibration by my own. Therefore I was happy Stefan the friend of Juergen helped me with the steam engine.
The rope sensor have been build by my own with a multi turn potentiometer and a return spring from an identiy card jo jo. Herbert a modelflying colleague sponsored me with fine steel wire . The accuracy of the rope sensor is in the range of 0.1 mm by 300mm displacement. I compared it to a digital gauge at my mill. This is much better then we need for this measurement.
The pressure sensors are chinese ones and i compared them to a pressure gauge with a good result. And they are low cost. The electronic is based on an arduino nano with bluetooth transmitting to the laptop. The software is my homebrew based on freebasic and is coming from DOS times with GW basic. In the field it is easier to act with key commands as with scroll down menus. So it is very good for this kind of work.
Juergen is now very happy with the valve adjustment and measurement. He made long runs of 2.6 an 3.6 km and noticed remarkable less coal and water consumption. And he can drive now very slowly and the engine starts now smooth and not like a wild horse as it was in the beginning.
In the next time we measure another engine. This one is older and have a very good run in.
It will be very interesting to see how this performance is in relation to the measured diagrams.
Here is an update of our activies from sunday. We made a steam meeting with four road steamers.
At the beginning as the engine was cold we change the valve setting of the Garret. With the electronic steam indicator we had after studying the measurements the idea to shift the valve 1.5 mm to the chimney to equal the pressure curves of the valve chambers. In total we changed 3 mm since the beginning. After the engine was under steam it was noticeable that the flywheel runs much smoother as before. Juergen made two long runs with 2..6 and 3.6 km and noticed a much improved consumption of water and coal. A great benefit is that the engine is now better to handle in slow driving. He is really satisfied now. His codriver Stefan noticed independantly the same.
i know the Maihak Indicator, but they are all similar. With my displacement sensor you see in the time diagram each stroke very clear and the pressure at each millimeter of piston travel.
My Software is quasi a digital storage oszilloskop software with the possibility to store in a file and show it in a
XY chart or here is it the indicator diagram . I can measure 8 Sensors in principle two independant compound cylinders with two setups 2 times diplacement and four pressures.
i do not know the Dobbie-Mcinnes steam indicator. In principle i measure the displacement by a multi turn potentiometer with a return spring. At the moment i have sensors for 300 and 250 mm displacement. So the piston travel is measured linear. The pressure sensors are connected to the draincock pipe at each end of the cylinder. This is equal to any kind of Indicators I saw in old books.
In two or three weeks we have our next steam meeting and so we tune Jürgens 4 inch Garret again. We will see how good we get the engine. I make a documentation again and I will try to show more details. But for me it is a one man show. With handling first my own engine , making a general video of us and then at the end of the session make the measurements and documentation. And it is working fine , but it is not a turn knob equipment.
|Thread: Merryweather Fire King|
congratulations to your running engine. Your engine need a run in time that is normal. And it depends on how good the valve is tight at the valve ports. And you need plenty of oil. The oil you give to the air pressure have not the same effect as later the mixture of steam and oil emulsion with water.
This is my experience I made.
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