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Post by delaplume on Aug 28, 2019 21:52:14 GMT
Quote}---------" and who cares about what judges say! Mine have had good words said about them by you good folk on this forum and by fellows in my local club, and that says it all to me."
Exactly !!!
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Post by Roger on Aug 28, 2019 21:57:15 GMT
A bit of a diversion again today, I like to play with different things to keep me interested and engaged with the project. This time it's a novel design for a blower to be used for raising steam. Yes, I know there are a simpler ways to do this, and yes, I'm sure there's no need to re-invent the wheel etc etc.... but... you know what I'm like! I have an intense disliking for the usual ones that get absolutely roasted while sitting on the chimney. I know they seem to last, but it just seems a horrible thing to do to a motor. You also need oven gloves to take the damned thing off when you're finished with it. So here's a little experiment that has had a few iterations already and one rather premature attempt to raise steam on a friends locomotive with an all plastic one protected in tin foil, just to see if it had enough suction. It didn't, but this one is similar but way more effective. The idea was to 3D print as much of it as possible, partly so I could easily experiment with changes in design, and partly because it's a challenge. Assembly by Timothy Froud, on Flickr So here's how it works. The motor has a 3D printed fan pushed onto the gear of the 12V motor which is slid into a 3D printed housing with a 3D printed spacer around it to allow air to pass over the motor. It also makes it easier to withdraw the motor with the fan in place. The fan also draws air through the four slots in the housing and this pressurises the chamber around the Bronze coloured Steel tube. Most of the air goes upwards to create a venturi which draws air through the tube and ejects it upwards. The cold air is surrounding and mixing with the smoke, so the plastic doesn't come into contact with hot gasses. A little of the air is allowed to escape through the thin Steel Grey coloured sleeve on the bottom via a series of 1mm holes. This reduces the cross sectional area of the Steel sleeve so as to reduce the heat transfered from the tapered Steel Light Blue bung that goes in the Chimney. The cold air is passing along the Steel sleeve and then out through the holes, keeping it cool enough so as not to melt the plastic. Sectioned assembly by Timothy Froud, on Flickr Here's what the Steel assembly looks like. The sleeves are tack welded to keep them in place. Steel assembly by Timothy Froud, on Flickr This is the central tube being made from 25mm Mild Steel Bar... 20190828_210732 by Timothy Froud, on Flickr ... and this will be the sleeve with the perforations. I could have made this from solid, but I thought it was easier to add the holes this way since I don't have a 4th axis and I didn't fancy drilling all of those by hand! 20190828_210740 by Timothy Froud, on Flickr This is the chimney bung... 20190828_220506 by Timothy Froud, on Flickr ... and the Steel and prototype parts together. 20190828_222628 by Timothy Froud, on Flickr The black 3D printed parts are made from ColorFabb HT which is a high temperature filament. It's going to have to sit in the Sun as well as being used on the locomotive, so PLA isn't really suitable. Hopefully this will be ready for another test soon, hopefully there will be enough suction this time.
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Post by simplyloco on Aug 28, 2019 22:13:55 GMT
A bit of a diversion again today, I like to play with different things to keep me interested and engaged with the project. This time it's a novel design for a blower to be used for raising steam. Yes, I know there are a simpler ways to do this, and yes, I'm sure there's no need to re-invent the wheel etc etc.... but... you know what I'm like! SNIP Agreed!
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Post by silverfox on Aug 28, 2019 22:43:45 GMT
Roger
I sometimes cannot keep up!!!
That is brilliant
Ron
( waiting fro the first 'Ahh but blowers are not made of plastic' comment)
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twombo
Seasoned Member
Posts: 120
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Post by twombo on Aug 29, 2019 1:50:41 GMT
Superb, Roger!
Bernoulli’s law in action. I dare say, the currentt. Discussions of drafting, blowers, blast pipes, petticoats, etc are causing some real intellectual ferment, here-abouts! If anyone in our illustrious group has the software, and, skills re: Solidworks plus, the flow simulation utilities, this may be a very good candidate for some long needed experimental physics!
Sir, this is some hare being “pulled from your Hat.” Very exciting! “Nothing up my sleeve” Presto!! Said the Prestidigitator!
Egads!!
Mick
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twombo
Seasoned Member
Posts: 120
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Post by twombo on Aug 29, 2019 2:23:33 GMT
Roger, Something like this; www.amazon.com/CRC-2105-Liquid-Detector-Aerosol/dp/B001B3BL0S. And a simple manometer might provide. Some simple means to show the desired differential pressure has been achieved. Having tuned SU carbies the last 40 years, My trusty Uni Syn comes to mind! “One point twenty-one Jig-a-watts”, a De Lorean, and, H.G. Wells, Here we come! Mick ... Your local Mad Scientist!
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Post by Roger on Aug 29, 2019 6:48:18 GMT
Superb, Roger! Bernoulli’s law in action. I dare say, the currentt. Discussions of drafting, blowers, blast pipes, petticoats, etc are causing some real intellectual ferment, here-abouts! If anyone in our illustrious group has the software, and, skills re: Solidworks plus, the flow simulation utilities, this may be a very good candidate for some long needed experimental physics! Sir, this is some hare being “pulled from your Hat.” Very exciting! “Nothing up my sleeve” Presto!! Said the Prestidigitator! Egads!! Mick Hi Mick, Some sort of Finite Element Analaysis of the whole arrangement would be really useful, it's surprisingly hard to get the proportions of these things close enough to get the desired suction. Small changes have huge effects, usually in the wrong direction! I increased the diameter of the fan since the first iteration and changed the blade design, all by eye, and it now moves a lot of air. I've tried several different tube sizes, experimented with the position of the inner tube and also the length of the outlet. All have a huge bearing on how well it works. My measurements have been no more than having different sized squares of cardboard to see how big a piece the suction will support. At present, it will support something around the size of a postcard. My first attempt struggled to hold a postage stamp, yet it almost got the locomotive into steam before my friend found his blower and we switched over to that. I don't think it needs a lot really. In the event that it's too strong, killing the suction couldn't be easier. I'll have a little rotary valve on the side to spill out some of the air. No need for motor speed controls. I've never seen that 'smoke in a can' before, what a strange product.
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oldnorton
Statesman
5" gauge LMS enthusiast
Posts: 717
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Post by oldnorton on Aug 29, 2019 9:32:13 GMT
Hi Roger
Yes I like the concept of a 'cool running' steam raiser. My only concern is the weight of the motor off to one side. The 'bung' fittings, if slack, seem to need a centralised motor mass otherwise it tips over.
Parallel thinking: what about a floor standing 12v compressor that connects by a length of flexible piping to one or more blower jets in an add-on chimney extension? I am not sure what pressure would be needed (20 psi ?) and how small and efficient such a compressor could be?
I think I have seen a length of small bore metal pipe bent and arranged to poke down a chimney, and presumably do the blowing task up the engine's own chimney.
Norm
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Post by gwr14xx on Aug 29, 2019 10:16:22 GMT
Hi Roger Yes I like the concept of a 'cool running' steam raiser. My only concern is the weight of the motor off to one side. The 'bung' fittings, if slack, seem to need a centralised motor mass otherwise it tips over. Parallel thinking: what about a floor standing 12v compressor that connects by a length of flexible piping to one or more blower jets in an add-on chimney extension? I am not sure what pressure would be needed (20 psi ?) and how small and efficient such a compressor could be? I think I have seen a length of small bore metal pipe bent and arranged to poke down a chimney, and presumably do the blowing task up the engine's own chimney. Norm Almost parallel thinking: Why not do what I have done - 'tee' off the blower pipe to a Schrader connector (from a car tyre) mounted on the main frames, and connect the compressor to that. The loco's own blower then does all the work.
Eddie.
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Post by Roger on Aug 29, 2019 11:19:54 GMT
Hi Roger Yes I like the concept of a 'cool running' steam raiser. My only concern is the weight of the motor off to one side. The 'bung' fittings, if slack, seem to need a centralised motor mass otherwise it tips over. Parallel thinking: what about a floor standing 12v compressor that connects by a length of flexible piping to one or more blower jets in an add-on chimney extension? I am not sure what pressure would be needed (20 psi ?) and how small and efficient such a compressor could be? I think I have seen a length of small bore metal pipe bent and arranged to poke down a chimney, and presumably do the blowing task up the engine's own chimney. Norm Hi Norm, The floor standing compressor solution is one that my friend Paul Tomlinson uses and it works really well. I've also seen the arrangement you describe for the bent pipe. All these things work, I just like to expore ideas, it's more fun. The bung is long and a good fit in the chimney, so having the weight to one side isn't a problem. I could see it being an issue if you didn't have a good adaptor though. I counterbalance weight could always be attached to the other side I suppose if you wanted to even it out.
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Post by Roger on Aug 29, 2019 11:24:47 GMT
Hi Roger Yes I like the concept of a 'cool running' steam raiser. My only concern is the weight of the motor off to one side. The 'bung' fittings, if slack, seem to need a centralised motor mass otherwise it tips over. Parallel thinking: what about a floor standing 12v compressor that connects by a length of flexible piping to one or more blower jets in an add-on chimney extension? I am not sure what pressure would be needed (20 psi ?) and how small and efficient such a compressor could be? I think I have seen a length of small bore metal pipe bent and arranged to poke down a chimney, and presumably do the blowing task up the engine's own chimney. Norm Almost parallel thinking: Why not do what I have done - 'tee' off the blower pipe to a Schrader connector (from a car tyre) mounted on the main frames, and connect the compressor to that. The loco's own blower then does all the work.
Eddie.
Hi Eddie, That's a neat solution, that's what they do with the 10-1/4" gauge locomotives I was playing with the other day. I suppose the only drawback on 1501 is that the connection would presumably have to be made inside the smokebox. I suppose you could use the steam lance fitting on the front for that! Does anyone pressurise the boiler itself with compressed air and then use the blower from that supply? I can see why you wouldn't want to do that on a Steel boiler, but I can't see it being an issue on a Copper one. That way you could back feed pressure into the Injector overflow so you wouldn't need any additional blumbing.
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Post by Cro on Aug 29, 2019 14:44:42 GMT
Almost parallel thinking: Why not do what I have done - 'tee' off the blower pipe to a Schrader connector (from a car tyre) mounted on the main frames, and connect the compressor to that. The loco's own blower then does all the work.
Eddie.
Hi Eddie, That's a neat solution, that's what they do with the 10-1/4" gauge locomotives I was playing with the other day. I suppose the only drawback on 1501 is that the connection would presumably have to be made inside the smokebox. I suppose you could use the steam lance fitting on the front for that! Does anyone pressurise the boiler itself with compressed air and then use the blower from that supply? I can see why you wouldn't want to do that on a Steel boiler, but I can't see it being an issue on a Copper one. That way you could back feed pressure into the Injector overflow so you wouldn't need any additional blumbing. Only that when things start to boil you have no idea what pressure you are at and then is there an issue of introducing compressed air in whilst creating steam??? We have an Aux blower much like Eddie on the club loco hidden behind a set of steps and uses the loco blower. Adam P.S think you'll find the scale steam lance is a bit diddy in 5" for anything other than being aesthetic!
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Post by Roger on Aug 29, 2019 16:20:17 GMT
Hi Eddie, That's a neat solution, that's what they do with the 10-1/4" gauge locomotives I was playing with the other day. I suppose the only drawback on 1501 is that the connection would presumably have to be made inside the smokebox. I suppose you could use the steam lance fitting on the front for that! Does anyone pressurise the boiler itself with compressed air and then use the blower from that supply? I can see why you wouldn't want to do that on a Steel boiler, but I can't see it being an issue on a Copper one. That way you could back feed pressure into the Injector overflow so you wouldn't need any additional blumbing. Only that when things start to boil you have no idea what pressure you are at and then is there an issue of introducing compressed air in whilst creating steam??? We have an Aux blower much like Eddie on the club loco hidden behind a set of steps and uses the loco blower. Adam P.S think you'll find the scale steam lance is a bit diddy in 5" for anything other than being aesthetic! That's a fair point, you would know the pressure, but not the temperature if you used compressed air up near the working pressure. You would only know when it blew off. I can't see anything wrong in principle with adding compressed air to a copper boiler though, unless I'm missing something? Ok, it would cool it down slightly, but that's not a deal breaker. It's just that if you can do that, there's no extra plumbing required. There's nothing stopping you using say 50psi though. When it's hot enough, the pressure will show the excess on the gauge. Yeah, the steam lance comment was a bit tongue in cheek, it's probably nowhere near big enough. I suppose the aux inlet to the blower could have a non return valve so you just have to plug in.
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Post by silverfox on Aug 29, 2019 16:35:55 GMT
Roger said
Yeah, the steam lance comment was a bit tongue in cheek, it's probably nowhere near big enough.
I am off to the bookies right now as i fully expect a working one on here in about a week! ( but wouldn't it be nice?)
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uuu
Elder Statesman
your message here...
Posts: 2,849
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Post by uuu on Aug 29, 2019 17:10:43 GMT
I suppose your injector wouldn't work until you'd purged the air?
Wilf
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Post by simplyloco on Aug 29, 2019 17:15:49 GMT
My MB came with a pretty powerful tyre inflator not much bigger than two fag packets : small and very handy! I wonder if that would be up to the job if routed through the blower jets? John
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Post by Roger on Aug 29, 2019 17:16:08 GMT
I suppose your injector wouldn't work until you'd purged the air? Wilf An interesting thought, I honestly don't know if that would be a problem or not. It might work anyway since the water impinging on the delivery cone probably doesn't care what it's pushing against. It would be interesting to try it out and see.
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jem
Elder Statesman
Posts: 1,072
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Post by jem on Aug 30, 2019 15:01:13 GMT
Its a bit sad to say bronze is wrong but stainless steel is ok, when it should be steel anyway,
what is the world coming to, perhaps someone should grow up?
an annoyed Jem
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Post by chris vine on Aug 30, 2019 17:38:49 GMT
Hi Roger,
I often used to steam up Bongo with a compressed airline connected to the injector overflow pipe. I would just put 20 psi in and the blower worked a treat.
Air didn't seem to stop the injector. I guess the steam had taken over from the blower long ago, so the air had been purged
I also made a small blower from a small plastic computer cooling fan. It just ran in all the smoke and hot gases. Obviously it wouldn't work, but it did. Lasted for ages too!!! Very quiet as well.
Chris.
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Post by terrier060 on Aug 30, 2019 19:08:36 GMT
An excellent aside if I may say so Roger. Now I want to see active suspension!!!
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