Here is a list of all the postings Brian John has made in our forums. Click on a thread name to jump to the thread.
|Thread: Has anybody built the flame eater "Nick"?|
I dragged this flame eater out of the cupboard to see if I can get it to work. It ran when I first built it but then refused to go ever since. The timing is okay : move the eccentric 1mm either way and the engine will not run so we can eliminate that as the problem. Piston/cylinder fit is very good : strong suction when I place my hand or finger over the end port. That leaves the ball valve arrangement. I enlarged the counter sink hole where the ball valve fits. This time I did it by hand as using the counter sink in a drill press or power drill results in small ridges which may affect the seal.
Some success ; I can get it to run for 5 minutes but then it fades and stops. It should run for about 10 minutes. Any suggestions as to how I can improve the running time ?
NOTE : sorry, I have a new computer and I cannot get the usual links to work.
Edited By Brian John on 07/09/2017 08:31:48
Edited By Brian John on 07/09/2017 08:35:24
|Thread: Has anybody built Beng's Danni Steam engine.|
I bought a new Ozito compressor from Bunnings today. The old compressor was most of the problem. Danni 2 runs very well now but there is still a small amount of air escaping from the front cover to the control valve. I will make a new one and see if that helps. I am still not sure about the pinholes in the solder so I might apply some 180 degree solder to them to plug them up.
The new compressor only runs for about 15 minutes before it gets very hot. Would purchasing a compressor with a tank increase the length of time the compressor can be run continuously (the duty cycle) ?
Edited By Brian John on 02/09/2017 07:53:29
The only holes I plugged were those holes from the steam chest to the cylinder as I did not want them to fill with solder. I used cut off toothpicks to do that. It was not a problem with the other engine but perhaps they were a tighter fit in this one.
UPDATE : I have watched closely to see if any air is coming from those holes and I do not think there is. I placed a few drops of water with a bit of detergent and I could not see any disturbance or bubbles. I think my air compressor has died this afternoon so I am not sure if I have an engine problem or not !
I will make the Al plate to go under the engine frame while I wait for a new compresssor to arrive from ebay.
Next project is a beam engine from Sussex Steam which I purchased from ebay. It is their old model beam engine and there is a lot more work in it than I expected. I suspect that is why the original owner sold it. Their newer version is much simpler to build but unavailable now due to illness according to their website.
Edited By Brian John on 01/09/2017 12:08:48
Edited By Brian John on 01/09/2017 12:26:51
That is one engine finished. It looks quite elegant with the timber lagging on the cylinder. I don't have any more of the thin strips of timber to do the second engine the same way so I will have to think of something else. I also have to add displacement lubricators to the engines before running them on steam.
The second engine is giving me problems : the solder joint between the cylinder and the steam chest keeps ending up with two or three pin holes along the seam. It looks like air is blowing out of there while the solder is setting. I pulled it apart and re-soldered it a second time but I am still having the same problem. I am not sure what is going on there as this did not happen to the first engine. I would take a photo but I do not think it would show up very well with my camera.
Edited By Brian John on 01/09/2017 02:49:37
Edited By Brian John on 01/09/2017 02:50:07
Edited By Brian John on 01/09/2017 02:52:25
|Thread: Who makes a displacement lubricator threaded 3/16-40 ?|
I will lookinto making my own and see what I can find in the way of plans.
Reagrds the Chinese lubricator : why is one side threaded and the other side is not ?
The PMR lubricators have one inlet/outlet pipe which is to be connected to a T junction. I have been using these for a few years but the postage costs from the US are getting prohibitive. I found these displacement lubricators from China but they have have two pipes. How are they connected ie. which is the inlet and which is the outlet ?
Edited By Brian John on 27/08/2017 14:25:52
|Thread: Has anybody built Beng's Danni Steam engine.|
Lawrie : your chuck probably weighs as much as my lathe
I spent the afternoon mucking around drilling and tapping holes and finally ended up with something I am happy with. I have drilled and tapped the 6mm thick aluminium plate to take two M2 X 14mm cap head screws which pass through the engine frame and the plate. These are further secured on the under side of the plate with two M2 nuts ( not necessary but I did it anyway). The plate was then screwed to the wooden block using five 5/8'' #2 wood screws ( five was overkill). I fitted the large flywheel and it all runs well.
Tomorrow I will glue the wooden lagging to the cylinder. That large bare space on the cylinders always looks a bit odd to my eye. I was going to file a flat on the crankshaft for the eccentric grub screw but then I realised that I would not be able to make any fine adjustments to the timing if I did that. Any thoughts on this ?
NOTE : I did think about painting the Al plate brunswick green but decided against it. And the same with the engine frame... it's really not worth it. The wooden lagging will give it a lift.
Edited By Brian John on 26/08/2017 11:41:56
Edited By Brian John on 26/08/2017 11:43:14
Edited By Brian John on 26/08/2017 11:48:23
Duly noted but I have already spent a few hours fidddling around with the aluminium plate and working out how it will fit. I have had a dry run and put it all together without drilling any holes and I don't think it looks too bad at all. The aluminium plate sets off the brass quite nicely.I will be glueing wooden lagging to the cylinder too ; that always looks good even though it serves no purpose. I have some small strips which are already varnished left over from a previous build.
To be honest, I think the supplied cast iron flywheel is too large for this small engine. The small brass flywheel I used in the video looks a more suitable size to my eyes.
You have a good point about using the wrong tool for cast iron. Can you post a photo of the tool you use when turning the flywheels ?
I am all astonished : it works !
I made two more control valves using some 6mm bronze bushes fixed to a 4mm steel rod. You can see the old steel control valve beside a new one in the video. I used CHEMTOOLS 8609 retaining compound. It should stand a constant temperature of 150 degrees Celsius. How hot does the steam chest get ? At least I know that the steam chest/cylinder assembly is correct and I do not have to remake that. I can now have another go at making an all steel control valve in case the retaining compound fails.
I still have to fit the larger cast iron flywheel by raising the engine mounting block by 5mm. I quite like the smaller brass flywheel though. Some screwed parts must be fixed in place with low strength Loctite as per the instructions. The engine runs very well first time ; it self starts as long as it is not on BDC.
NOTE : that 8609 retaining compound grabs in less than 5 seconds so be warned. Forget about the 10 minute fixture time as per the website !
Edited By JasonB on 24/08/2017 08:59:36
I made another control valve cover today but I still have the same problem. It could mean the bore for the control valve is not perpendicular to the end of the steam chest. That could be due to the quality of the drill press or the ineptitude of the operator....or both !
What to do next ? I think I will have to use the Teflon packing arrangement that PM Research use on their engines. That should allow for a bit of error. I can't quite remember how they did it but I will look closely at online photos.
You can see the parts 29, 4 , 30 and 18 in the exploded diagram below. They use this arrangement for the piston rod but I should be able to use something similar for my control valve.
Edited By Brian John on 22/08/2017 14:38:33
|Thread: Would you buy a second hand laptop computer ?|
I have decided to buy a new computer but nobody is doing any good deals on new laptops in Cairns at the moment so I will have to take what I can get. JB HIFI have two HP laptops. Both run Windows 10 : the 14'' costs $500 and has 4GB RAM, 1TB HDD and a 2.0 GHZ processor. The 15'' costs $600 and has 8GB RAM, 1TB HDD and a 2.5 GHZ processor. I spent an hour in the store today doing various things and the larger 15'' is definitely faster. I wanted a 14'' screen but I will have to go with the larger and faster computer.
Neither computer has a DVD reader/burner so I will have to buy an external device.
Edited By Brian John on 21/08/2017 10:20:31
Edited By Brian John on 21/08/2017 10:21:48
|Thread: Has anybody built Beng's Danni Steam engine.|
Jason : it was not screwed down when I took the photo hence that gap. I have measured all the holes and they are in the correct positions. The control valve is also the correct dimensions so I am not sure what the problem is. The front hole is being fully covered and the rear hole is being partially covered so something is wrong. I think I need to desolder the steam chest from the cylinder. The remelt temperature of the solder paste is about 340 degrees so it should not be too difficult. I do not know what sort of a mess I will be left with once the two pieces are pulled apart.
Lawrie : what is happening with your control valves and the steam holes ?
NOTE : I thought this engine build would be on par with the their Stirling engine kit !
I have removed the steam chest cover to observe the operation of the control valve as it moves back and forwards. When it is in the forward position should the steam hole on the right be open or closed ? And when it is in the rear position should the steam hole on the left be open or closed ?
I have measured the hole positions and the control valve but something is not quite right. I may have to desolder the steam chest and start again.
Edited By Brian John on 21/08/2017 08:07:25
Edited By Brian John on 21/08/2017 08:08:44
I have re-read the instructions concerning the control valve cover and watched that instructional video again : I had the cover on the wrong way ! The spigot goes inside the steam chest not outside as I had it positioned. Thinking I had solved the problem, I then tried it in the new position...just the same. I also tried the other steam chest and the other cover...just the same.
I am really not sure what is going on here now. There is nothing else to do but make a new control valve cover and see what happens. The engine is 98% complete but unless I can get this part to fit properly then it will not run.
Weary : thank you for that video. I may as well start with that ; it looks good. Yes, adjusting the eccentric will be a nuisance due to the hidden grub screw. I realised that yesterday when I was putting the engine together for the first time.
I just had a disconcerting thought : what if the problem is not the rear control valve spigot but the bore for the control valve is off centre by a few degrees ? I think the PM RESEARCH engines use a Teflon packing arrangement in this area. I have sold those engines so I cannot have a look at it now but that is something to consider if all else fails.
Edited By Brian John on 20/08/2017 00:59:27
I had intended to place that Al. plate under the small block of wood so that the existing holes would not be visible. I have plenty more Al. that I can cut to that size so a new plate could be made to fit on top of the small block and under the engine frame as suggested. At this point , I am not sure which would look better.
Bunnings have some Tasmanian Oak which is 25mm thick so I could also cut and varnish another block of timber. It would probably look better than the block of plywood supplied with the kit.
Lawrie : machining cast iron on my small machine is a real pain. I do not get a good finish so I have to spend a long time polishing it up using 120 to 1500 grit wet and dry. It is far easier to raise the engine a few mm. This is why I prefer brass flywheels ; I get a good finish with little polishing necessary.
Do you intend to add timber lagging to the cylinders at some point ? I have found that looks quite good. I use JB WELD to glue the timber strips in position. The strips are varnished first on both sides with three coats of matt clear.
Edited By Brian John on 19/08/2017 17:50:47
Yes, that makes sense but I am not sure how that could have happened. I made two of everything and the other one is no better. I need to work out what I did wrong before I try making another. (The other side is flat.)
I have gone ahead and assembled the rest of the engine without that rear cover. There was a problem with the eccentric being too thick but I have machined that down and everything now runs smoothly.
Setting the timing : where should the control valve be with the piston is at TDC ?
Edited By Brian John on 19/08/2017 12:03:50
Edited By Brian John on 19/08/2017 12:11:08
I have found some 5mm thick aluminium plate which will fit under the small wooden block. There is a piece of it in the photos below already cut to the exact size from another job. I will fit that later and in the mean time I will use a smaller flywheel from the spare flywheel box.
I got the main piston moving smoothly in the cylinder ; that did not take too long. But the big problem is the control valve (21) and its rear cover. I have spent over an hour filing, fiddling and fettling but I cannot get the control valve to move once the rear cover is tightened. Just that last little bit (1/8 turn) to tighten the screws will jam it stuck. I am out of ideas for the moment. I may have to make another control valve although I am not confident that will solve anything. I have already widened the holes through which the screws pass from 2.2mm to 2.6mm.
Edited By Brian John on 19/08/2017 07:39:22
Edited By Brian John on 19/08/2017 07:40:06
Edited By Brian John on 19/08/2017 07:41:08
There will be a bit of fettling required tomorrow to get the piston to run smoothly in the cylinder for the full stroke. I think I know how to fix that. But the unexpected problem is that the flywheel cannot be fitted on the axle : the supplied small block of timber on which the engine frame sits is 18mm thick and this is not high enough to allow the flywheel to be fitted. It needs to be at least 20mm thick to give enough clearance for the flywheel. I don't have anything to hand at the moment so I will have a look in Bunnings scrap bin tomorrow.
Lawrie : how thick are your supplied small blocks of timber ?
DOH : I did not take enough off the flywheels when I machined them. Diameter should be 80mm but mine are 82mm. I was not thinking of clearance when I machined them.
Edited By Brian John on 18/08/2017 12:45:51
I finished the piston today and fitted it to the piston rod using two M3 X 5mm grub screws. I filed two flats in the piston rod as discussed above. I also put low strength Loctite down each screw hole before tightening everything up. I just realised that all the parts are made..... it is actually finished ! All I have to do now is assemble it and hope it works. If it doesn't then I will have a very interesting paperweight.
Edited By Brian John on 18/08/2017 08:06:17
Edited By Brian John on 18/08/2017 08:08:13
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