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Toymaker

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Bentwings

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I realy don’t know what to expect from these two turbines I’ve already seen others like them with gear boxes that came apart both tried to put heavy grease or oil in the gear train and met with a mess. I’ve got a Hand full of small Electric high speed motors that could possibly convert to mini generators . Actually I got them for something to keep me busy .

byron
 

ajoeiam

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blank (like some others I've noticed)
I realy don’t know what to expect from these two turbines I’ve already seen others like them with gear boxes that came apart both tried to put heavy grease or oil in the gear train and met with a mess. I’ve got a Hand full of small Electric high speed motors that could possibly convert to mini generators . Actually I got them for something to keep me busy .

byron
I wish you were closer - - - I'd have lots of ideas for you to 'keep busy' with - - - grin!!!!!
 

Bentwings

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I just about finished assembly last night. Mostly just the intake and exhaust parts left. Lots of purse anyway.
I did look at th piston ports in the cylinder chest. They are small I didn’t measure them but another 1/8” dia at best . For now I’m goingvto just leave them alone . There will be far more pressure available if needed. I’m considering this in automotive terms. We talk about boost getting 40 psi boot is huge. In auto terms. Steam it could be 140 psi and not even be excessively hot I don’t plan on stressing this little engine like that however. 40 is supposed to be normal pressure. Assembled there is a lot more friction than I thought. But with pressure on the pistons and fresh supply of oil I think it will stabilize nicely . There is huge amount of flywheel weight two 3” main plus an smaller but pretty heavy for it’s size steel flywheel I haven’t weighed them yet but the should smooth ou piles nicely . I need a short hose and a couple fittings so I YHINK I’ll walk up to the auto parts store and get them . Of all the really dumb things I’ve done I put my brand new 1/4 40 TPI me tap an die set some where unknown I still have 1/4 in brake pipes so all is not lost. It’s somewhere I just can’t find it . I need my daily walk anyway we have been snowed in again so it will be good to get out. I ordered a flex coupling today so the main flywheel won’t have to connect bot engines . I will reside on the short part of number two crankshaft so it won’t be hanging on a single bearing . Hopefully I can test run tonight.
byron
 

mrehmus

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I just cannot resist this cartoon as it seems to apply to many of us:
275192345_5262530337093249_2859606048966787052_n.jpg

And I have lost a few of the 40 TPI set pieces anyway.
 

Bentwings

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I just cannot resist this cartoon as it seems to apply to many of us:
View attachment 134830
And I have lost a few of the 40 TPI set pieces anyway.
Haha, how true. I just went through my wor desk and found a couple things I might need later. I put them where logic says would be a good place easily remembered . Yeah right I’m not a Vulcan.
Still can’t fine that valuable pair of tools my cat would not even snif them so she didn’t run off with them . I getting desperate as I need both to go much farther . I’m about to install the eccentrics I’d like to put a flat on the crank so the mount screws coil dig in . I found u carbide spotting drills on McMaster this would allow exact location. There are sizes that allow them to act like a drill but very short dull flutes so the can be run down a threaded hole without damaging the threads. I’d like to power up the engines so I can get the timing exact then spot drill do I can grind a flat or drill point. I’m going to see what the screw thread really is before doing any thing . That’s the next step then I’ll install the intake and exhaust parts. I had a big interruption to day so I’m getting a late start.
byron
 

Bentwings

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Hi Byron,
  • 1/4" wall x 3" OD aluminium tube (Welded end plates??) should be OK for 100psi.
  • NWP, safety-valve full blow before 104psi.,
  • Hydraulic test at 200psi. (compensating for the change of permissible tensile stress between temperature of hydraulic test and temperature at Boiler steam pressure).
  • You must reinforce all tube wall penetrations with at least double the cross-sectional area of aluminium reinforcement. - Often standard bushes are way undersized to do this properly! Not sure how you do this on a welded boiler? - (Fillet?) Weld-section greater than tube wall-thickness? - Ask a man who makes ASME certified pressure vessels in aluminium...
  • End plate minimum thickness depends on flat or dished, joining method to the tube, what holes and where positioned, any fillets for reinforcement, any stays, or flue tubes connecting both ends, etc.
Enjoy the design work!
K2
im new at boile design and new to steamers. To prevent end cap blow out I died a tension rod between end caps the rod will hold more in tension than i could ever pressurize the boiler to except a runaway. There seems several relief valves planned for various things the boiler itself will probably not see much over 150 psi. The upper heater will have capability of a lot more if I can get electrical power.. I came up with an idea today for power. I have a 10k watt portable generator that has 220 vac outlets it may need carb work as I haven’t used it I n some time Its electric start and would barely fit in my storage shed . It would be limited to occasional running I think . It would provide a big boost in electric power without over loading my home . I may still have the 220 extension cord too. It has both 220 and 120 outlets so might even be enough to power the boiler and superheater . It’s at a friends shop in a dark corner . I’m sure he woul like to see it leave , maybe even bring it over for me. . I have to give more thought to this.
byron
 

Bentwings

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Haha, how true. I just went through my wor desk and found a couple things I might need later. I put them where logic says would be a good place easily remembered . Yeah right I’m not a Vulcan.
Still can’t fine that valuable pair of tools my cat would not even snif them so she didn’t run off with them . I getting desperate as I need both to go much farther . I’m about to install the eccentrics I’d like to put a flat on the crank so the mount screws coil dig in . I found u carbide spotting drills on McMaster this would allow exact location. There are sizes that allow them to act like a drill but very short dull flutes so the can be run down a threaded hole without damaging the threads. I’d like to power up the engines so I can get the timing exact then spot drill do I can grind a flat or drill point. I’m going to see what the screw thread really is before doing any thing . That’s the next step then I’ll install the intake and exhaust parts. I had a big interruption to day so I’m getting a late start.
byron
Yeah we’ll keep laughing . I still have not found the tap or die. They are in a small plastic bag it’s in my steam stuff. This little engine assembly has taken my entire build area. About all that got done today Ed polish the marks out of the crankshafts an remove the grub screws from the flywheels an install M3 socket head screws. At lest the engines turn over with out binding I walked up to the auto parts store and got the connection hose fittings and clamps. I’m going to have to make some special service tools as I have various Allen wrenches all over. I need long skinny ones withou much hex drive on the end. Ball ended I desperately need a demagnetized. The screws are stainless but there are steel an cast iron parts the wrenches stick to.
byron
 
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Hi Byron. Did you manage to align the main bearings of the 2 engines nicely? I have been thinking about the coupling.... it will take all the torsional variation of the 2 engines working against each other at different parts of the stroke, unless exactly aligned so TDC on one is TDC on the other. Then the torsional input from one will be at the same time as t'other, so torsional variation across the coupling will only be flywheel input and output, from remote engine to flywheel. ( I think?). What did you think?
K2
 

Bentwings

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Hi Byron. Did you manage to align the main bearings of the 2 engines nicely? I have been thinking about the coupling.... it will take all the torsional variation of the 2 engines working against each other at different parts of the stroke, unless exactly aligned so TDC on one is TDC on the other. Then the torsional input from one will be at the same time as t'other, so torsional variation across the coupling will only be flywheel input and output, from remote engine to flywheel. ( I think?). What did you think?
K2
I used a 6mm stainless steel rod to alight bothe engines then slight each other . I’m jus moving one engine so I hav more room for the flywheel . I also ordered a flexible beam coupling rather than just use the fly wheel. I’m going to counter bore the coupling and use the clamping feature to hold and locate the flywheel. I too was concerned about the vibration between the engines. I also came up with a better way to accurately adjust and set the timing. I found the the depth end of the “ very near” caliper will go in the port on the piston valve so I can measure it’s exact osition and change it as needed. Just like setting the timing on the race cars . Carting this farther we use heavy duty clamps to hold the ignitions in place so I found I can machine a counter bore in clamp shaft collars that will cover the grub screw. Thi will hold the eccentric much better than the grub screw . I’ll also make up a spacer to replace the eccentric hub. This way I can turn the eccentric around on he crank so I can secure it better but still be ale to adjust it. I have four of them to prepare . Shaft collars and coupling should be here Thursday then I give them to my grand son to prepare . With gas prices so high I just can’t get out to the shop myself but son and grand son come by once or twice a week on errands . I looked a long time for couplings . I really wanted a disc coupling as they are shorter but I have enough shaft for the one I purchased. I might have got carried away with the shaft packing as the crank is stiffer now. Both spun nicely especially with the flywheels. They actually turn fine with the main fly wheel . I just don’t like the set screw or now socket head screw as it Mars the crankshaft. I’ve already sanded it couple times. The split shaft collars will allow tight clamping with no damage I did consider a shear pin but even 2mm hole in the crank is too much weakening.
min just putting the manifolds together now they are ugly and very inefficient. Plus quite complicated with all the screws and threaded fittings. As I’m doing this I’m rolling around a nice header exhaust and similar intake. I can do it in either copper or stainless. I like the stainless as I can cut lengths and polish them before bending and cutting they will be ultra clean so easy to silver braze . I’m thinking about a 4 into one collector like we use on the racers. . This would exit into the condenser. I’m not sure about the super heater t I’m still learning about this end of he system . I’ve gone backwards today as I have to move one engine so everything’s separated. Fortunately the fly wheel has a long center so it aligns the crankshafts crankshafts nicely. I’m goingvto see if I can at least test the engines tonight I’ve got the stuff for hook up but I just have to get it together . Later
Byron
 
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Hi Byron, please don't forget 3 things about steam boilers.
  1. Your Normal Working Pressure (NWP ) shall be not exceeding the max working pressure for the engine.
  2. The boiler design shall exceed 8 x the NWP without over stressing any material or component. (That's the law everywhere if you want your insurance to be valid).
  3. The safety valve shall fully lift at NWP plus 4% and that's on full heater power. If the pressure rises higher you need a bigger or additional safety valve.
There are laws covering what you should do, created by the best Engineers, so please follow the guidance, and don't go off on your own ideas.....
We can only advise on this site, so give our best advice.
You can still feel free to do something else if you think you know better, so I am simply advising from my own knowledge and experience.
K2
 

Bentwings

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When I can't find a tool and buy a replacement, I usually go to put the new one away in its 'logical place' and find the old one already there...
that is so true. . I have lots of double tools. What then happens is I think we’ll I have extra ones of these so I modify one for a special purpose then find I just used my only one for a modified tool now I don’t have a standard tool . I have a box of special tools. I pick one modified one up an ask” what’s this for?” No idea. LOL

BYRON
 

Bentwings

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Hi Byron, please don't forget 3 things about steam boilers.
  1. Your Normal Working Pressure (NWP ) shall be not exceeding the max working pressure for the engine.
  2. The boiler design shall exceed 8 x the NWP without over stressing any material or component. (That's the law everywhere if you want your insurance to be valid).
  3. The safety valve shall fully lift at NWP plus 4% and that's on full heater power. If the pressure rises higher you need a bigger or additional safety valve.
There are laws covering what you should do, created by the best Engineers, so please follow the guidance, and don't go off on your own ideas.....
We can only advise on this site, so give our best advice.
You can still feel free to do something else if you think you know better, so I am simply advising from my own knowledge and experience.
K2
im working with in guidelines . This is why I can’t have a fired unit in my home I realy don’t like my soldering torch it’s tiny but if I had not used them for years in work I wouldn’t even have that either. I’ll have a pressure gage right at the engine inlet so I’ll know exactly what the engines are operating at to give the desired performance this will allow of any losses due to cooling in the inlet line, so boiler pressure, temp will have its own gages so this can be monitored the super heater will also have its gages. It probably would be more accurately callus super warmer as that will be its real purpose . I really don’t think it’s necessary to have super hot steam . It’s purpose will be to expand and cool as the gas it is used like a conventional air tank . I it may sound a little far fetched but I’m severely lacking in high pressure steam knowledge I understand strength of materials and I’m aware that heat can affect them . I do appreciate input. Once this assembly is completed I’ll have time to sit down and do some cad work the coupling I ordered from Amazon won’t be here untill mid May so I found another that I should have Fri along with the shaft collars. I’ll get the minor modifications done right away so I can finish up the full assembly. I thought it important to create accurat timing so it’s repeatable after service it’s a relatively easy clamping method so I don’t have to deal with grub screws or odd socket head screws. Timing should be a matter of measurement with dial calipers rate than an “ about centered” system . After that maybe somebody can come up with optimation . There is not much to work with the eccentrics have a maximum lift and the ports are fixed so really any radical changes will mean new piston slide valve cylinders maybe special is ton valve this is not a race engine so I’ll just leave as best it can be made for what it is. After all it is super charged as it is so more pressure is like more boost there just isn’t detonation to deal with and burned pistons and parts it’s really not going to
Byron run faster than a blown top fuel motor idles at .
 

Bentwings

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im working with in guidelines . This is why I can’t have a fired unit in my home I realy don’t like my soldering torch it’s tiny but if I had not used them for years in work I wouldn’t even have that either. I’ll have a pressure gage right at the engine inlet so I’ll know exactly what the engines are operating at to give the desired performance this will allow of any losses due to cooling in the inlet line, so boiler pressure, temp will have its own gages so this can be monitored the super heater will also have its gages. It probably would be more accurately callus super warmer as that will be its real purpose . I really don’t think it’s necessary to have super hot steam . It’s purpose will be to expand and cool as the gas it is used like a conventional air tank . I it may sound a little far fetched but I’m severely lacking in high pressure steam knowledge I understand strength of materials and I’m aware that heat can affect them . I do appreciate input. Once this assembly is completed I’ll have time to sit down and do some cad work the coupling I ordered from Amazon won’t be here untill mid May so I found another that I should have Fri along with the shaft collars. I’ll get the minor modifications done right away so I can finish up the full assembly. I thought it important to create accurat timing so it’s repeatable after service it’s a relatively easy clamping method so I don’t have to deal with grub screws or odd socket head screws. Timing should be a matter of measurement with dial calipers rate than an “ about centered” system . After that maybe somebody can come up with optimation . There is not much to work with the eccentrics have a maximum lift and the ports are fixed so really any radical changes will mean new piston slide valve cylinders maybe special is ton valve this is not a race engine so I’ll just leave as best it can be made for what it is. After all it is super charged as it is so more pressure is like more boost there just isn’t detonation to deal with and burned pistons and parts it’s really not going to
Byron run faster than a blown top fuel motor idles at .
inreceived 6 beam shaft couplers today , all wrong not what unordered st all. I spent an entire afternoon trying to get these ordered correctly every time I went back to check wat was ordered it had changed I noted this to Amazon and that I was unhappy.
Now I’m goingvto have to alter parts to be what I wanted and paid for . I could send them back but I already have too much time in them . The mods are relatively easy but still more of my time I can use extra couplings , I just did not wantvtonhavecto alter them to what I should have received. If I had machineryvat home I’d fix them myself, but now I have to wait untill tomorrow to get out to my sons shop then get these fixed up . It’s an entire afternoon fooling around. The only thing I can say isI’ll have a solution to a problem fixed for good. Plus I can check on my boiler progress. I did find my missing 1/4 40 TPI me tap and die set about an hour before I was going to reorder them .
byron
 
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Hi Byron, re"superheat": the prefix means "more than", or in this case "above", meaning "more temperature than the boiler", or higher temperature than the boiler. 1 degree, or 1000 degrees is "more than", but I bet you'll achieve 10 or 50 degrees "above boiler temperature" without too much bother, and this will dry the steam (not cool it!), won't destroy the lube oil inside the cylinder and significantly improve the performance, without increasing the boiler pressure above NWP for the boiler. (SO the boiler stays safe, engine performs better, and you are happier!).
Ok?
K2
 

Bentwings

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Hi Byron, re"superheat": the prefix means "more than", or in this case "above", meaning "more temperature than the boiler", or higher temperature than the boiler. 1 degree, or 1000 degrees is "more than", but I bet you'll achieve 10 or 50 degrees "above boiler temperature" without too much bother, and this will dry the steam (not cool it!), won't destroy the lube oil inside the cylinder and significantly improve the performance, without increasing the boiler pressure above NWP for the boiler. (SO the boiler stays safe, engine performs better, and you are happier!).
Ok?
K2now we are getting closer to what I’m after . I’ll obviously monitor pressure and temp especially as it comes on line the super heater or “ super warmer” will be to remove the water vapor by heating and pressurizing according to tables I really don’t know what to expect as far as humidity or dryness . Certainly better dryness than the air compressor. And yes I don’t want to run so hot the oil breaks down and I start getting coorosion of brass as there is lots of it in this little engine I’m hoping the anodes I have will help as they did in the boat .
I don’t intend to run excessive temps or pressure. I’llhave a gage to monitor actual operating pressure the engines are running at. I’m sure this will vary as loads change.
I got the beam coupler I ordered except Amazon got it all wrong . I got 6 instead of two. No shaft collars the couplings were supposed to be split but they are set screw locked. So I’ve come up with a modification to split the mount as I wanted then counter bore the ends so I can lock the flywheels and the eccentrics to the crankshafts without marring it . It also will allow micro adjusting the timing as I found a way to measure the exact location of the piston valve . Once I get the manifolds connected I’ll be able to do a test run. My grand son will do the minor machine work as it’s impractical for me to get to the shop now with the ridiculous gas prices . If I can make a day of it I can get a lot done as I think I have all the parts and materials. Need. Maybe a couple of lathectools but those are available locally. I found my 1/4 40 TPI tap and die plus I just got the 1/16” npt tap and die set and another small metric tap and drill set. I’ve got some shaft collars coming tomorrow. If they gethere in tim I’ll get them made into locking collars like I originally wanted . I’ll be able to do a couple different configurations.
the intake and exhaust system is just a big night mare . There are a bunch of m2 screws that are to just see even with lighted msg glass there are hex nuts that I don’t have a skinny wrench for yet so I’ll have to use the needle nose for now . Of all things thes nuts are custom size so I discovered last night that I’ll need more of them so something else to make fortunately Ifound some hex standoffs that I YHINK can be drilled tapped and cut off for the right thickness I’ll make a custom headers and intake manifold after I get the system up and running

byron
 
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Hi Byron. Superheater is the correct technical term. If you study how and what they do, there is a pressure gradient - according to Gas Laws, rising from boiler pressure according to how much heat (not "warmth") is being added to the steam, once all the vapour (wet mist) has turned into steam (a gaseous version of H2O = water molecules). But while there is any vapour present, the heat added is taken up by the vapour and converts the vapour into steam, according the the latent heat part of the steam tables. So while there is any vapour present, the pressure and temperature changes do not comply with the Gas Laws. Hence the need for the steam tables that have been derived, by experts, empirically.
Does this help your understanding?
K2
 

Bentwings

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Hi Byron. Superheater is the correct technical term. If you study how and what they do, there is a pressure gradient - according to Gas Laws, rising from boiler pressure according to how much heat (not "warmth") is being added to the steam, once all the vapour (wet mist) has turned into steam (a gaseous version of H2O = water molecules). But while there is any vapour present, the heat added is taken up by the vapour and converts the vapour into steam, according the the latent heat part of the steam tables. So while there is any vapour present, the pressure and temperature changes do not comply with the Gas Laws. Hence the need for the steam tables that have been derived, by experts, empirically.
Does this help your understanding?
K2
yes it does help. I have a set of steam tables I’ve been looking at. I think I’m beginning to under stand the various stages or conditions of steam. Pressure and temps are related. It will be interesting to see all this in action . I won’t be at the limits by any means but I think I’ll know the condition of the steam as I create and use it .
I do have an unanswered question I did a lot of searching to find origins of steam oil and it’s composition even though I’ve used steam cleaning to clean things all the way back to when I was about 12 yr old washing milk cans . Can you believe I was given insulated gloves and about a 1” I’d live steam hose to clean these things as well as the room and he tanker truck. There was about a foot of invisible steam befor there was vapor . I don’t think OSHA existed back then It definitely cleaned stuff. Even in the auto shop we had a live steam cleaner . I cleans those car and truck engines like new. Most of the paint went down the drain with the road grime .
Anyway as I got into really high performance Rc airplanes oils became important. Initially castor oil was the go to then synthetics. Of late the silicone oils have become popular in high performance Rc cars and in some of our Rc aircraft . 2 stroke gas engines like 50:1 or more oil ratios. There are high temp and very high film strength silicone oils coming along I experimented with some a while ago but it was hard to develope a baseline then add tests . It either worked or resulted in seized engines. The silicone plastics don’t seem to do well at higher temps but the gear oil really does work in differentials and miniature transmissions .
So if I use compressed air temporarily the silicone oils might be ok. But I think some testing with real steam might be in order.
I’ve got several viscosities so I thought maybe just pour some on clean silverware from the kitchen then take the boiling water from my coffee pot and see if it washes off with out soap of course . The top of my new pot is right at 200 degF and even the carfe is 200 some times a little more if I let it sit. I know this is far below what real steam might be but there would be some indication I think just wiping the piston rod where it comes through the packing gland sure made a difference in friction. None of the crankshaft bearings will see very high temps . I think maybe a little heavier oil might be better there but I’ll need to actually get this thing running. I finally got all the intake and exhaust parts put together. Those m2 screws are really tiny and there are a lot of them . Once I get the modified shaft collars and beam coupling installed I YHINK vibration will be minimum. I found Teflon tubing with the correct I’d so I can now make prongs for the packing instead of the messy tape .
 
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