Re: Exhaust configuration [was; Re: Materials Compatability]
Trot Fox, A nozzle orifice can be too small or it can be too large! If it's too small there may be the velocity to create some pressure drop in the smoke box but not enought volume to be effective. Example, a 1mm orifice in a 1" scale loco wouldn't work very well!! The nozzle has to be just right to obtain the right blast and that is what Tony is writing about Geoff. Interesting... I thought I had read that you should increase the nozzle >size to decrease the blast? Larger nozzle means slower jet speed and >therefore less draught, not to mention less restriction on the exhaust >taking up power. > >Guys? What's up with that? > >Trot, the somewhat confused, fox... > >At 05:30 PM 3/31/03, you wrote: >>Hi Geoff, >>Yes, you are correct. I did mean the exhaust nozzles. They both have >> in fact already been reduced once by Mike, to reduce the fierceness of >> the blast, which had caused the previous high temps, and blistered >> paint!. This weekend, with the red coals flying, the casing temperature >> was reading 286F. So I guess I am getting up there again, and you may be >> correct about the load. >>My track has some tight radii and "S" bends, plus 7 coaches at 50lbs+, >> engine at 28lbs, >>and a thick coating of white hot anthracite certainly makes the blast >>pipes bark.. Whereas on a large plain oval track, with the same load and >>constant momentum, the blast is much quieter. As to be expected. >>I have concerns about fitting a mesh screen after firing up, what is >> the melting point of facial skin!??. I guess I have to learn when to >>back off!. >>Have a great day. >>Best Regards, >>Tony D. > > > /\_/\ TrotFox \ Always remember, > ( o o ) AKA Landon Solomon\ "There is a > >\_/< [EMAIL PROTECTED] \ third alternative." >
Exhaust configuration [was; Re: Materials Compatability]
Interesting... I thought I had read that you should increase the nozzle size to decrease the blast? Larger nozzle means slower jet speed and therefore less draught, not to mention less restriction on the exhaust taking up power. Guys? What's up with that? Trot, the somewhat confused, fox... At 05:30 PM 3/31/03, you wrote: Hi Geoff, Yes, you are correct. I did mean the exhaust nozzles. They both have in fact already been reduced once by Mike, to reduce the fierceness of the blast, which had caused the previous high temps, and blistered paint!. This weekend, with the red coals flying, the casing temperature was reading 286F. So I guess I am getting up there again, and you may be correct about the load. My track has some tight radii and "S" bends, plus 7 coaches at 50lbs+, engine at 28lbs, and a thick coating of white hot anthracite certainly makes the blast pipes bark.. Whereas on a large plain oval track, with the same load and constant momentum, the blast is much quieter. As to be expected. I have concerns about fitting a mesh screen after firing up, what is the melting point of facial skin!??. I guess I have to learn when to back off!. Have a great day. Best Regards, Tony D. /\_/\ TrotFox \ Always remember, ( o o ) AKA Landon Solomon\ "There is a >\_/< [EMAIL PROTECTED] \ third alternative."
Re: Materials compatibility
Tony, Interesting, JR May had some very good comments, J R?? is that James Robert, John Richard, Jack Roger or what?? Anyway, a friend and I often thought of a control valve to modulate the amount of steam that is admitted to the exhaust nozzle from the cyls, just as the blower can be controlled, this would really give one control and economy. If one wasn't too fussy about the prototype, the control valve handle or wheel could be at the exterior side of the smoke box.In fact, I believe this has been done on the prototype. Sir Art, Harry, Keith, JR-(not of Dallas!) and others I forgot to mention--what do you know about that--tell us. With heavy apologies to Mister Cole, I fired the Maisie GNR 3/4" scale loco today after several months. I wasn't aware of any cinders flying but the coal ashes were burning in the ash pan--another natural occurrence? Right JR? (not of Dallas!) . It does have a hell of a blast--I should steam it at nite for a fireworks display. With Steam, fire and now Brimstone, Geoff Hi Geoff, >Yes, you are correct. I did mean the exhaust nozzles. They both have in >fact already been reduced once by Mike, to reduce the fierceness of the >blast, which had caused the previous high temps, and blistered paint!. This >weekend, with the red coals flying, the casing temperature was reading >286F. So I guess I am getting up there again, and you may be correct about >the load. >My track has some tight radii and "S" bends, plus 7 coaches at 50lbs+, >engine at 28lbs, >and a thick coating of white hot anthracite certainly makes the blast pipes >bark.. Whereas on a large plain oval track, with the same load and constant >momentum, the blast is much quieter. As to be expected. >I have concerns about fitting a mesh screen after firing up, what is >the melting point of facial skin!??. I guess I have to learn when to back >off!. >Have a great day. >Best Regards, >Tony D. > >a At 12:17 PM 3/31/03 -0800, Geoff Spenceley wrote: >>Tony, >> >>Any discussion of coal, blowers and exhaust nozzles is always worth >>discussion. Firstly, I would hazard a guess that cinders (in pieces of >>eight?) from the chimney would be more likely be a problem with the >>smaller scales. You write blower, do you mean the exhaust nozzle too, or >>just the blower? >> >>I have a few problems with cinders on the 3/4" scale but only one >>occurrence of any significance was a few years ago with an OS Porter, the >>cinders caught my hair on fire and started a small grass fire--the engine >>was working hard and the nozzle blast caused the cinders to fly from the >>stack. It was great! >> >>The stainless steel mesh may work might work but I wouldn't bother--even >>the prototypes ( according to Steam World) would blow out cinders when >>working hard. It's probably those heavy J&M coaches you haul with the >>Duchess. On the other hand is the exhaust nozzle the right size--should it >>be enlarged--or reduced? >> >>One suggestion, if you can stand the departure from realism, would be to >>have a spark arrester you can insert in the chimney after steam is up, like >>a piece of stainless steel tube with a SS screen--the tube could be a tight >>fit--but would that interfere with the draught--( slurp)? Well time to >>experiment! You can Americanize a small pwrt of the Duchesss! >> >>In closing, I say: Let the sparks fly, or, "Let the FIRE Fall" as we said >>in Yosemite yesteryear when the fire was dropped from Glacier Point! >> >>Geoff >
Re: Materials compatibility
Perhaps these are the "screens" you refer too?. I have thought > of trying a temporary fireplate to my 10mm coal engines though. > Regards, > Tony D. > Tony, The screens J.R is refering to are located in the smoke box, and right in front of the tube sheet. It is a heavy coarse wire cloth, also refered to as "front end netting" and sometimes has a hole size of about 1/2". I think the whole idea was to not obstruct the flow of gasses, but those particles that hit the netting would loose some of their energy, and loose their incandescence. The netting I have seen usually runs from the top of the smoke box, down to a point about even with the exhaust nozzle, and "stirs up" the mix, without putting too much of a restriction in the flow of gasses. When cinders hit this netting, they usually fall down to the bottom of the smoke box, where they can be removed by opening a cinder clean out, or if they are still airborne, in a front end of the Hall-Slater self cleaning style, will not be glowing anymore, and hopefully less of a fire risk. Remember that J.R. said he was talking about full sized practice. I think this is another area where "you can't scale down mother nature!" In our No. 1 guage locos, the coal we use is smaller than the cinders stopped by the smoke box netting J.R. is refering to! Keith Taylor Keith Taylor
Re: Materials compatibility
Hi JR, I agree, I did not really want to have to put a screen inside the petticoat, unless a last resort, and already feared it may affect the path of the nozzle blast. So I just will have to back off on the blower a little, and just enjoy the sparks as opposed to the 1/8"+ size cinders. At 10mm scale, did the 1/1 scale engine really throw out 4" cinders if firebox screens were not fitted?. I do not recall having to duck from these, even when climbing Shap Summit and 18 coaches on. I do not recall seeing "screens" per se', inside the fireboxes either, only the arches or fireplates. Perhaps these are the "screens" you refer too?. I have thought of trying a temporary fireplate to my 10mm coal engines though. Regards, Tony D. At 04:24 PM 3/31/03 -0500, JR May wrote: The screening on a full size locomotive was not below the petticoat. That is just a bad place for it and would hinder draft way too much. In the smoke box there are screens and baffles that catch the cinders which gives more surface area for the screening. Check the Locomotive Dictionary for a picture or I can scan it for you. A diamond stack might be another approach which has a funnel like thing in the base of the diamond which catches many of the cinders and they fall to a collection spot in the stack. Bottom line? Cinders are a fact of life, even with baffles and screens. I'd risk a fire or two myself! It makes it more interesting. - Original Message - From: Geoff Spenceley <[EMAIL PROTECTED]> To: Multiple recipients of sslivesteam <[EMAIL PROTECTED]> Sent: Monday, March 31, 2003 3:17 PM Subject: Re: Materials compatibility > Tony, > > Any discussion of coal, blowers and exhaust nozzles is always worth > discussion. Firstly, I would hazard a guess that cinders (in pieces of > eight?) from the chimney would be more likely be a problem with the > smaller scales. You write blower, do you mean the exhaust nozzle too, or > just the blower? > > I have a few problems with cinders on the 3/4" scale but only one > occurrence of any significance was a few years ago with an OS Porter, the > cinders caught my hair on fire and started a small grass fire--the engine > was working hard and the nozzle blast caused the cinders to fly from the > stack. It was great! > > The stainless steel mesh may work might work but I wouldn't bother--even > the prototypes ( according to Steam World) would blow out cinders when > working hard. It's probably those heavy J&M coaches you haul with the > Duchess. On the other hand is the exhaust nozzle the right size--should it > be enlarged--or reduced? > > One suggestion, if you can stand the departure from realism, would be to > have a spark arrester you can insert in the chimney after steam is up, like > a piece of stainless steel tube with a SS screen--the tube could be a tight > fit--but would that interfere with the draught--( slurp)? Well time to > experiment! You can Americanize a small pwrt of the Duchesss! > > In closing, I say: Let the sparks fly, or, "Let the FIRE Fall" as we said > in Yosemite yesteryear when the fire was dropped from Glacier Point! > > Geoff > > Hi Geoff, > >Of course, they were "pieces of eight". Just using a little poetic > >licence relative to the correct lapping method you described. > > > >Question:- If I start getting 1/8" size red hot coals being thrown out > >of the "chimney", of the Duchess, does this mean the blower draught is a > >little strong!?. (Joke, but true). > >I now think I may need to place a piece of stainless steel mesh inside > >the bottom of the petticoat, primarily to keep such sparkies inside the > >smokebox, but it also needs to sit below the suction fan nozzle at fire-up. > >However, the mesh may also affect the path of the blower jet and disperse > >it before it enters the petticoat, thereby minimising its intended affect. > >Have you experienced a similar problem from your "large scale", > >Britannia?, or are you waiting to set your real estate on fire yet first?. > >Any thoughts?. > >Regards, > >Tony D. > > > >At 03:06 PM 3/28/03 -0800, Geoff Spenceley wrote: > >>"Ello Tony, > >> > >>Trust you to be a "smart alec"--I thought they were pieces of eight!! Well, > >>you have the Duchess and the Britannia, so you must know! > >> > >>Cheers, > >> > >>Geoff. > >> > >> > > > > > >
Re: Materials compatibility
Hi Geoff, Yes, you are correct. I did mean the exhaust nozzles. They both have in fact already been reduced once by Mike, to reduce the fierceness of the blast, which had caused the previous high temps, and blistered paint!. This weekend, with the red coals flying, the casing temperature was reading 286F. So I guess I am getting up there again, and you may be correct about the load. My track has some tight radii and "S" bends, plus 7 coaches at 50lbs+, engine at 28lbs, and a thick coating of white hot anthracite certainly makes the blast pipes bark.. Whereas on a large plain oval track, with the same load and constant momentum, the blast is much quieter. As to be expected. I have concerns about fitting a mesh screen after firing up, what is the melting point of facial skin!??. I guess I have to learn when to back off!. Have a great day. Best Regards, Tony D. a At 12:17 PM 3/31/03 -0800, Geoff Spenceley wrote: Tony, Any discussion of coal, blowers and exhaust nozzles is always worth discussion. Firstly, I would hazard a guess that cinders (in pieces of eight?) from the chimney would be more likely be a problem with the smaller scales. You write blower, do you mean the exhaust nozzle too, or just the blower? I have a few problems with cinders on the 3/4" scale but only one occurrence of any significance was a few years ago with an OS Porter, the cinders caught my hair on fire and started a small grass fire--the engine was working hard and the nozzle blast caused the cinders to fly from the stack. It was great! The stainless steel mesh may work might work but I wouldn't bother--even the prototypes ( according to Steam World) would blow out cinders when working hard. It's probably those heavy J&M coaches you haul with the Duchess. On the other hand is the exhaust nozzle the right size--should it be enlarged--or reduced? One suggestion, if you can stand the departure from realism, would be to have a spark arrester you can insert in the chimney after steam is up, like a piece of stainless steel tube with a SS screen--the tube could be a tight fit--but would that interfere with the draught--( slurp)? Well time to experiment! You can Americanize a small pwrt of the Duchesss! In closing, I say: Let the sparks fly, or, "Let the FIRE Fall" as we said in Yosemite yesteryear when the fire was dropped from Glacier Point! Geoff Hi Geoff, >Of course, they were "pieces of eight". Just using a little poetic >licence relative to the correct lapping method you described. > >Question:- If I start getting 1/8" size red hot coals being thrown out >of the "chimney", of the Duchess, does this mean the blower draught is a >little strong!?. (Joke, but true). >I now think I may need to place a piece of stainless steel mesh inside >the bottom of the petticoat, primarily to keep such sparkies inside the >smokebox, but it also needs to sit below the suction fan nozzle at fire-up. >However, the mesh may also affect the path of the blower jet and disperse >it before it enters the petticoat, thereby minimising its intended affect. >Have you experienced a similar problem from your "large scale", >Britannia?, or are you waiting to set your real estate on fire yet first?. >Any thoughts?. >Regards, >Tony D. > >At 03:06 PM 3/28/03 -0800, Geoff Spenceley wrote: >>"Ello Tony, >> >>Trust you to be a "smart alec"--I thought they were pieces of eight!! Well, >>you have the Duchess and the Britannia, so you must know! >> >>Cheers, >> >>Geoff. >> >>
Re: Materials compatibility
The screening on a full size locomotive was not below the petticoat. That is just a bad place for it and would hinder draft way too much. In the smoke box there are screens and baffles that catch the cinders which gives more surface area for the screening. Check the Locomotive Dictionary for a picture or I can scan it for you. A diamond stack might be another approach which has a funnel like thing in the base of the diamond which catches many of the cinders and they fall to a collection spot in the stack. Bottom line? Cinders are a fact of life, even with baffles and screens. I'd risk a fire or two myself! It makes it more interesting. - Original Message - From: Geoff Spenceley <[EMAIL PROTECTED]> To: Multiple recipients of sslivesteam <[EMAIL PROTECTED]> Sent: Monday, March 31, 2003 3:17 PM Subject: Re: Materials compatibility > Tony, > > Any discussion of coal, blowers and exhaust nozzles is always worth > discussion. Firstly, I would hazard a guess that cinders (in pieces of > eight?) from the chimney would be more likely be a problem with the > smaller scales. You write blower, do you mean the exhaust nozzle too, or > just the blower? > > I have a few problems with cinders on the 3/4" scale but only one > occurrence of any significance was a few years ago with an OS Porter, the > cinders caught my hair on fire and started a small grass fire--the engine > was working hard and the nozzle blast caused the cinders to fly from the > stack. It was great! > > The stainless steel mesh may work might work but I wouldn't bother--even > the prototypes ( according to Steam World) would blow out cinders when > working hard. It's probably those heavy J&M coaches you haul with the > Duchess. On the other hand is the exhaust nozzle the right size--should it > be enlarged--or reduced? > > One suggestion, if you can stand the departure from realism, would be to > have a spark arrester you can insert in the chimney after steam is up, like > a piece of stainless steel tube with a SS screen--the tube could be a tight > fit--but would that interfere with the draught--( slurp)? Well time to > experiment! You can Americanize a small pwrt of the Duchesss! > > In closing, I say: Let the sparks fly, or, "Let the FIRE Fall" as we said > in Yosemite yesteryear when the fire was dropped from Glacier Point! > > Geoff > > Hi Geoff, > >Of course, they were "pieces of eight". Just using a little poetic > >licence relative to the correct lapping method you described. > > > >Question:- If I start getting 1/8" size red hot coals being thrown out > >of the "chimney", of the Duchess, does this mean the blower draught is a > >little strong!?. (Joke, but true). > >I now think I may need to place a piece of stainless steel mesh inside > >the bottom of the petticoat, primarily to keep such sparkies inside the > >smokebox, but it also needs to sit below the suction fan nozzle at fire-up. > >However, the mesh may also affect the path of the blower jet and disperse > >it before it enters the petticoat, thereby minimising its intended affect. > >Have you experienced a similar problem from your "large scale", > >Britannia?, or are you waiting to set your real estate on fire yet first?. > >Any thoughts?. > >Regards, > >Tony D. > > > >At 03:06 PM 3/28/03 -0800, Geoff Spenceley wrote: > >>"Ello Tony, > >> > >>Trust you to be a "smart alec"--I thought they were pieces of eight!! Well, > >>you have the Duchess and the Britannia, so you must know! > >> > >>Cheers, > >> > >>Geoff. > >> > >> > > > > > >
Re: Materials compatibility
Tony, Any discussion of coal, blowers and exhaust nozzles is always worth discussion. Firstly, I would hazard a guess that cinders (in pieces of eight?) from the chimney would be more likely be a problem with the smaller scales. You write blower, do you mean the exhaust nozzle too, or just the blower? I have a few problems with cinders on the 3/4" scale but only one occurrence of any significance was a few years ago with an OS Porter, the cinders caught my hair on fire and started a small grass fire--the engine was working hard and the nozzle blast caused the cinders to fly from the stack. It was great! The stainless steel mesh may work might work but I wouldn't bother--even the prototypes ( according to Steam World) would blow out cinders when working hard. It's probably those heavy J&M coaches you haul with the Duchess. On the other hand is the exhaust nozzle the right size--should it be enlarged--or reduced? One suggestion, if you can stand the departure from realism, would be to have a spark arrester you can insert in the chimney after steam is up, like a piece of stainless steel tube with a SS screen--the tube could be a tight fit--but would that interfere with the draught--( slurp)? Well time to experiment! You can Americanize a small pwrt of the Duchesss! In closing, I say: Let the sparks fly, or, "Let the FIRE Fall" as we said in Yosemite yesteryear when the fire was dropped from Glacier Point! Geoff Hi Geoff, >Of course, they were "pieces of eight". Just using a little poetic >licence relative to the correct lapping method you described. > >Question:- If I start getting 1/8" size red hot coals being thrown out >of the "chimney", of the Duchess, does this mean the blower draught is a >little strong!?. (Joke, but true). >I now think I may need to place a piece of stainless steel mesh inside >the bottom of the petticoat, primarily to keep such sparkies inside the >smokebox, but it also needs to sit below the suction fan nozzle at fire-up. >However, the mesh may also affect the path of the blower jet and disperse >it before it enters the petticoat, thereby minimising its intended affect. >Have you experienced a similar problem from your "large scale", >Britannia?, or are you waiting to set your real estate on fire yet first?. >Any thoughts?. >Regards, >Tony D. > >At 03:06 PM 3/28/03 -0800, Geoff Spenceley wrote: >>"Ello Tony, >> >>Trust you to be a "smart alec"--I thought they were pieces of eight!! Well, >>you have the Duchess and the Britannia, so you must know! >> >>Cheers, >> >>Geoff. >> >>
Re: Materials compatibility
Hi Geoff, Of course, they were "pieces of eight". Just using a little poetic licence relative to the correct lapping method you described. Question:- If I start getting 1/8" size red hot coals being thrown out of the "chimney", of the Duchess, does this mean the blower draught is a little strong!?. (Joke, but true). I now think I may need to place a piece of stainless steel mesh inside the bottom of the petticoat, primarily to keep such sparkies inside the smokebox, but it also needs to sit below the suction fan nozzle at fire-up. However, the mesh may also affect the path of the blower jet and disperse it before it enters the petticoat, thereby minimising its intended affect. Have you experienced a similar problem from your "large scale", Britannia?, or are you waiting to set your real estate on fire yet first?. Any thoughts?. Regards, Tony D. At 03:06 PM 3/28/03 -0800, Geoff Spenceley wrote: "Ello Tony, Trust you to be a "smart alec"--I thought they were pieces of eight!! Well, you have the Duchess and the Britannia, so you must know! Cheers, Geoff. Hi Geoff, >As Punch said to Judy, (or the Duchess to Britannia), and Long John >Silver's parrot. >"That's the way to do it, figures of eight, figures of eight"!. >Regards, >Tony D. > >At 12:24 PM 3/27/03 -0800, you wrote: >>Royce, >> >>Based on my experience in the compressed air industry, I would suggest the >>following: >> >>The valve block surface and the valves should be finally finished with >>1000 grit on a properly precision machined steel plate , then on a piece >>of "real" plate glass using a very light lapping compound such as bon-ami, >>to the extent where a high polish (like a mirror) is obtained indicating >>that there are no scratches or burrs. The parts should be moved on the >>glass in a figure eight movement, preferably to a back and forth or >>circular movement. This will help insure that the surface of the parts are >>polished evenly. Intensive washing of the parts to remove all the abrasive >>materials and metal is essential when all is done. Before all this make >>sure the ports are clear of burrs and wash thoroughly--you don't want chips >>of metal to be around as you start the lapping procedure. >> >>Geoff. >> >>Hi Phil. Thanks for responding to my dilemma. On initial installation, >> >I think I hit the valve face and port face with 600 grit wet or dry & >> >oil before the first run. But I didn't break the sharp edge on the >> >bottom of the valve. On the first run, it may be that the assembly oil >> >( read that turbine oil) may have run "dry" (although I would be >> >surprised if that happened within 5 minutes of running). However,the >> >scratches (which I am assuming are the result of galling) reappeared >> >after removal of the inital scratches by re- honing. The plans call >> >for both parts to me made of brass, so I am beginning to think that >> >there is a problem with the "bronze" that I used to make the valves. >> > Some impurities may be causing the problem. >> > >> >royce in SB >> > >> >Phil Paskos wrote: >> > >> >>Hmm. >> >> If the materials are finished well, no sharp edges etc and you're using >> >>steam oil that is getting to the ports, I'm surprised that is happening. >> >> >> >>Phil P >> >> >> >> >> >> >> > >> > >> >> >> >
