And dad built three hot air engines, from various published designs.
My Dad's (Bob J's) Shop
- Thread starter GreenTwin
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As I mentioned previously, none of dad's engines were museum-grade, but it was a casual hobby for him, and he was in it for the fun of it.
There is no denying that dad had a blast riding his steam bikes, and his steam auto, at the various engine shows.
Dad's machining was very good on every engine, and they ran perfectly, but dad was a machinist for many years, doing repairs for the family lumber company.
One thing you could say about dad is that if he started a design, he would finish it, and in the end it would run well.
There is something to be said for finishing every engine you ever start.
I have made a number of practice engine pieces (most of them ruined when nearing completion), but only one complete engine (see photos below), and I must say it is quite a challenge to make an engine from scratch, and even more challenging to document it in 2D/3D.
This is my one and only engine to date, but I have so many in the design stage.
Unfortunately I am still a working stiff, and may remain that way for quite some time, baring a stroke-out or something like that.
Every machining step had to be made up in my head, and the majority of the machining steps were a first for me.
This engine basically picked up where my dad left off, but with the parts cast in 356 aluminum, and the flywheel cast in gray iron, in the backyard foundry.
It is a rather difficult task to come in behind someone who had built 38 engines, especially if you don't know how to build an engine, which was the case for me when I began this engine in 2012.
It was a steep learning curve to say the least.
There is no denying that dad had a blast riding his steam bikes, and his steam auto, at the various engine shows.
Dad's machining was very good on every engine, and they ran perfectly, but dad was a machinist for many years, doing repairs for the family lumber company.
One thing you could say about dad is that if he started a design, he would finish it, and in the end it would run well.
There is something to be said for finishing every engine you ever start.
I have made a number of practice engine pieces (most of them ruined when nearing completion), but only one complete engine (see photos below), and I must say it is quite a challenge to make an engine from scratch, and even more challenging to document it in 2D/3D.
This is my one and only engine to date, but I have so many in the design stage.
Unfortunately I am still a working stiff, and may remain that way for quite some time, baring a stroke-out or something like that.
Every machining step had to be made up in my head, and the majority of the machining steps were a first for me.
This engine basically picked up where my dad left off, but with the parts cast in 356 aluminum, and the flywheel cast in gray iron, in the backyard foundry.
It is a rather difficult task to come in behind someone who had built 38 engines, especially if you don't know how to build an engine, which was the case for me when I began this engine in 2012.
It was a steep learning curve to say the least.
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WOW! That is an extremely impressive "resume" of your Dad's work! Do you still have those? Would make a nice museum display!
That is a gorgeous work for a first one! Curiosity makes me ask: What is that white assembly in the background of the second picture?
I have never seen one like that before. Imagining how it works, "Vane" type oscillator. sure would like to see plans for it. Do you know what it is called?
I have the same 3D printer! Great choice. I added the MMU2 to mine, can print 5 different colors/materials. Colors easy, different materials can be a bit tricky.
I am a retired machine design engineer, but never heard of different ratio's with the same diameter gears! I will have to check that out.
I still have 16 of them and access to 2 that other family members have, so I can take 18 to shows.
It makes for a pretty nice display, and I run them all on (except the hot air engines) on compressed air.
Here is a display table I had at the Soule museum in Meridian Mississipi in 2017.
I have accumulated a few more, such as a Cretors No.1 and 2, and the castings for a No.6.
This dispplay is in the foundry where all of the Soule Speedy Twins were cast.
You can see the large cupola in the background.
I guess you are talking about the linear plastic bag dispenser.
It has narrow and wide continuous tubes on it, and to cover a roll of drawings, you just pull off a length, cut it off, and tie a knot on the ends.
I have been in the engineering business for 36 years, which is one of the reasons I went with Solidworks, since there were some projects that needed that level of 3D coordination.
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That is the Robertson Semi-Rotary.
Two square cylinders, each single-acting, in a horseshoe arrangement.
Dad made it from a couple of engravings published in a Lindsay book.
This was one of those engines that Tom Lindsay said to my dad "I bet you can't build one of these!".
Dad promptly built two of them, and returned one to Lindsay (the one below).
Below are my dad's sketches/drawings for the Roberston.
A bit rough, but effective.
You can see from the cutting oil that he probably had them out in the shop, using them to build the two he made.
I started toying around with this engine in 3D, but have not gotten very far with it.
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Here is my 3D attempt at the Roberstson Semi-Rotary.
I tried to keep the parts for this model at an accurate scale.
My dad's Roberston was free-lanced, like many of his engines, and so did not adhere very well to scale.
I generally insert an engraving of an old engine into AutoCad, draw a grid over it, and then draw the sketches for one part at a time, which I then import into Solidworks (this is what I did to create the green twin using only 3 photos of the original engine).
I tried to keep the parts for this model at an accurate scale.
My dad's Roberston was free-lanced, like many of his engines, and so did not adhere very well to scale.
I generally insert an engraving of an old engine into AutoCad, draw a grid over it, and then draw the sketches for one part at a time, which I then import into Solidworks (this is what I did to create the green twin using only 3 photos of the original engine).
I researched it online, and so far I can't find any reference to it, even from some very notable helical gear manufacturers who have a great deal of information on their websites.
As I recall, the gear manufacturers sell helical gears at 90 degrees with a 2:1 ratio, but one gear is twice the size of the other.
I assumed that the gears had to be 2:1 in size in order to get the 2:1 ratio, but looking at old photos of Frisco Standard engines, it appeared that the gears driving the vertical shaft were the same diameter.
Luckily my buddies across the pond (many thanks to JasonB) showed me how a 2:1 ratio can be achieve using two helical gears of the same diameter. It is rather tricky to model in 3D, and while the angles are close to 30 and 60 degrees on the teeth, the angles are not exactly 30 and 60 degrees, for reasons that I still don't fully understand.
JasonB and friend have it in a spreadsheet, which is how the exact angles are obtained.
The two helical gears that I 3D printed are from JasonB, and they mesh and operate flawlessly, and give the 2:1 speed ratio.
For those who make their own gears, as I understand it no special cutter is needed, a standard cutter will work fine.
I am going to cast mine.
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I like the Prusa, but I wish the bed was about twice as big.
I end up having to piece patterns together from multiple prints.
The Prusa is not perfect, but for the price break it is ok.
Here are the patterns I printed for a Dake.
My models tendo to be on the grand scale as far as model sizes go, which really helps me to see and machine engines.
The Dake I think was derived from a Roots design (it would appear that way when comparing the Dake patent drawings with the 20 years previous and almost identical Roots engine).
The Dake is a two piston engine in a common cylinder (chamber).
The pistons are flat, and one rides inside the other.
The porting for this engine is genius, and this is where Dake improved on the Roots design.
The basic design is Roots though.
I was 3D printing a part one time, and ran out of filament, so I just fed another roll into the carriage, which happened to be a different color.
So I discovered how to do multi-color with a standard Prusa.
This was a piece that started out as a belt buckle, but then got rather oversized.
It was something to cast during the pandemic/shutdown, and was just a quick sketch I threw together in AutoCad, and then imported into Solidworks.
They came out of the mold clean and bright, just as is seen in the video.
Cleaning off the sand after casting required only a light brushing with a dry paintbrush.
I think I buffed the top one in the last photo a bit.
Cast in gray iron.
This was fun, and gave me something to cast when all the foundry and engine shows were shut down (many still are shut down).
Two heavy for a belt buckle, unless you are a serious boss of a belt wearer (some folks are).
So I discovered how to do multi-color with a standard Prusa.
This was a piece that started out as a belt buckle, but then got rather oversized.
It was something to cast during the pandemic/shutdown, and was just a quick sketch I threw together in AutoCad, and then imported into Solidworks.
They came out of the mold clean and bright, just as is seen in the video.
Cleaning off the sand after casting required only a light brushing with a dry paintbrush.
I think I buffed the top one in the last photo a bit.
Cast in gray iron.
This was fun, and gave me something to cast when all the foundry and engine shows were shut down (many still are shut down).
Two heavy for a belt buckle, unless you are a serious boss of a belt wearer (some folks are).
Very nice work that your father did! Did he show any of his work at NAMES?
I am very interested in the Standard, I will be following you on that.
That's a mighty large printed model, Nice,Nice!
I am very interested in the Standard, I will be following you on that.
That's a mighty large printed model, Nice,Nice!
Yes, steel only. The basic procedure is to heat the part dull red hot, coat well with Kasenit, reheat to bright cherry red, quench. Alternately, you can make a container to hold the part with Kasenite packed around it and heat the whole thing up to the quench point, then quench.
Dad never displayed any of his engines at NAMES.
I have discussed with several people about displaying my dad's engines (at least displaying the engines that I still retain, about 18 of them) at NAMES.
One of the people I was discussing this with actually attended NAMES after the discussion, and when he returned, he said "Your dad's engines are not on the NAMES level".
I attended NAMES for the first and only time in 2019, and my friend was right in that generally the engines that are displayed at NAMES are museum-grade level, or above, and I consider many of them masterpieces, such as Rich's Monitor.
My dad's hobby was a casual one, basically to give him something to do after retirement.
Dad used a freelance approach to building models, and his drawings/sketches contained just enough information to get the geometry worked out, and to produce a functioning engine.
Often dad only had one or two engravings to go by, and he had to figure out how it all worked, and get the valve gear timing in the ballpark, which is no easy feat.
Some criticisms of my dad's work that I have seen on forums have been "He was a by-the-seat-of-the-pants designer", and this is absolutely true.
As I have stated before, there is no right or wrong way to build a model engine (many would disagree with this statement).
The right way to build a model engine is to use a way that makes you happy.
Nobody should be in the model building business only with the intent of making others happy, but deriving no joy of their own from the process.
Generally speaking, model engines often seem to be build by machinists, tool and die makers, and others with the skill set required to understand and complete the tedious process of building an engine.
I am not a machinist; have never done tool-and-die work, had never done any foundry work prior to 2012, and had never built a complete engine prior to the first (and only) engine I have completed.
So I sort of break the typical model engine builder mold, but am perhaps a good example of demonstrating that many things can be learned and mastered regardless of one's background or current technical skills.
There is really no limits regarding what a person can learn, if one has the desire to learn.
I had a professor one time who had some great jokes, and one of his jokes was "Do you know what is the best way to finish writing a term paper?".
We all looked at him dumbfounded. His response was, in a very loud voice "TO START THE TERM PAPER !!!!", while waving his hands wildly in the air.
And so it goes with model engine building.
The only way to learn engine building is to start with something simple, build it, master the steps, and then move on to a more challenging engine.
The key is to START, with the understanging that many mistakes will be made, and the frustration level at the beginning will be very high.
Dad's engines will never be featured in any model builder's hall of fame, but when taken as a group, they are an example of how you can build some fairly complex engines, and thoroughly enjoy doing so.
The level of work that someone seeks to attain is a personal thing, and everyone has their own motivations and objectives.
I don't judge others for their current level of work, but rather admire the learning road that they are traveling on, and and wonder how far they may go in the hobby.
Dad was criticized for his lack of rigourous design, but that was never his intent, and that is an artifical requirement for model engine building. Dad did exactly what he set out to do, which was build a lot of functional model engines, and have a tremendous amount of fun doing so.
I prefer a making more exact replicas of old engines, and deep diving into the technical aspects of a design, to identify, document, and preserve the original design intent and function exactly, but that is just my approach, chosen because I prefer it that way, not because that is the only way to build engines.
If I displayed the remaining engines of my dad's at NAMES, it would be as a group, with some sort of disclaimer that it was dad's casual hobby, all for fun.
While none of my dad's engines would be what I consider "great designs/builds" in the grand (NAMES) scheme of things, I find the span/breadth of dad's engine work to be interesting, and I think it serves as an illustration of what can be achieved on a hobby level, beginning with a very simple wobbler.
.
I have discussed with several people about displaying my dad's engines (at least displaying the engines that I still retain, about 18 of them) at NAMES.
One of the people I was discussing this with actually attended NAMES after the discussion, and when he returned, he said "Your dad's engines are not on the NAMES level".
I attended NAMES for the first and only time in 2019, and my friend was right in that generally the engines that are displayed at NAMES are museum-grade level, or above, and I consider many of them masterpieces, such as Rich's Monitor.
My dad's hobby was a casual one, basically to give him something to do after retirement.
Dad used a freelance approach to building models, and his drawings/sketches contained just enough information to get the geometry worked out, and to produce a functioning engine.
Often dad only had one or two engravings to go by, and he had to figure out how it all worked, and get the valve gear timing in the ballpark, which is no easy feat.
Some criticisms of my dad's work that I have seen on forums have been "He was a by-the-seat-of-the-pants designer", and this is absolutely true.
As I have stated before, there is no right or wrong way to build a model engine (many would disagree with this statement).
The right way to build a model engine is to use a way that makes you happy.
Nobody should be in the model building business only with the intent of making others happy, but deriving no joy of their own from the process.
Generally speaking, model engines often seem to be build by machinists, tool and die makers, and others with the skill set required to understand and complete the tedious process of building an engine.
I am not a machinist; have never done tool-and-die work, had never done any foundry work prior to 2012, and had never built a complete engine prior to the first (and only) engine I have completed.
So I sort of break the typical model engine builder mold, but am perhaps a good example of demonstrating that many things can be learned and mastered regardless of one's background or current technical skills.
There is really no limits regarding what a person can learn, if one has the desire to learn.
I had a professor one time who had some great jokes, and one of his jokes was "Do you know what is the best way to finish writing a term paper?".
We all looked at him dumbfounded. His response was, in a very loud voice "TO START THE TERM PAPER !!!!", while waving his hands wildly in the air.
And so it goes with model engine building.
The only way to learn engine building is to start with something simple, build it, master the steps, and then move on to a more challenging engine.
The key is to START, with the understanging that many mistakes will be made, and the frustration level at the beginning will be very high.
Dad's engines will never be featured in any model builder's hall of fame, but when taken as a group, they are an example of how you can build some fairly complex engines, and thoroughly enjoy doing so.
The level of work that someone seeks to attain is a personal thing, and everyone has their own motivations and objectives.
I don't judge others for their current level of work, but rather admire the learning road that they are traveling on, and and wonder how far they may go in the hobby.
Dad was criticized for his lack of rigourous design, but that was never his intent, and that is an artifical requirement for model engine building. Dad did exactly what he set out to do, which was build a lot of functional model engines, and have a tremendous amount of fun doing so.
I prefer a making more exact replicas of old engines, and deep diving into the technical aspects of a design, to identify, document, and preserve the original design intent and function exactly, but that is just my approach, chosen because I prefer it that way, not because that is the only way to build engines.
If I displayed the remaining engines of my dad's at NAMES, it would be as a group, with some sort of disclaimer that it was dad's casual hobby, all for fun.
While none of my dad's engines would be what I consider "great designs/builds" in the grand (NAMES) scheme of things, I find the span/breadth of dad's engine work to be interesting, and I think it serves as an illustration of what can be achieved on a hobby level, beginning with a very simple wobbler.
.
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As a former board of directors member of the NAMES organization I would say this is exactly the type of collection that should be displayed. Engine building is a hobby and all levels of models should be displayed. The devil is in the details and all these engines run (most without any detail drawings) and the gloss could always be added later if that was what the builder wanted. Just my opinion.
karl
Your Dad's engines are awe inspiring, very nicely made showing a real talent in machining and assembling. The real awe inspiring thing to me is the large amount of work done over a relatively short time in history!
This is good to hear, and I agree with you that there are all levels, and they should all be displayed.
I have always learned from all the models, even the simple ones, and the simple models can display some very creative things.
More importantly, I think that for the hobby to survive, there needs to be support at all levels, because without support of the beginners, there is nobody in the pipeline to move up to the more advanced work.
I have tried to leave a paper trail of everything I do and discover, so that others may perhaps follow down the path of engine building one day.
So far I have posted complete pdf drawings (open source for non-commercial use) for the Dake, and Bernay steam engines.
Complete drawings for the green twin have been posted in Live Steam this year, and at some point I will post a pdf of those drawings as well.
I am working on a complete set of drawings for the Speedy Twin, and have about four sheets completed.
The Speedy Twin is a very complex and compact engine, and those drawings are not easy, nor is the 3D model.
I am very grateful for those who publish drawings for their builds, since everyone can learn from this information, and more importantly, the information is not lost over time, as is so often the case.
I will try to get back to NAMES one day, and I hope that show can continue in a post-COVID world.
I could bring my dad's remaining 18 engines, and my green twin, along with various other engines such as a Cretors No.1 and 2.
This remains a challenging year for me and my family on many fronts, and so it is one day at a time.
I could also put on a very good casting seminar. They had a casting seminar in 2019, and it left much to be desired in my opinion.
Backyard casting has come a long way in the last 10 years, and many things are now possible on a hobby setting that were considered impossible (or too difficult for a backyard caster) not too many years ago.
A casting seminar needs to be comprehensive I think, and include manual pattern making, 3D modeling/3D printed patterns, molding, basic metalurgy, foundry equipment construction, and casting aluminum and gray iron.
Brass/bronze is sort of a special animal, and I leave that endeavor to others, although I have dabbled in.
The beauty of casting gray iron is that unlike brass, there are no zinc fumes to contend with, and no burnout of the zinc.
Aluminum 356 works well if you control the gassing.
Edit: While my dad's engine's drawings were on the light side as far as being traditional details drawings, they do capture the geometry of the engines exactly, and that is what is critical for an engine to function well.
All of my dad's engines run flawlessly, but they they could be improved upon with a careful analysis of valve gear design and timing.
Dad generally ignored cutoff, and used a model engine style valve with a late cutoff, in lieu of an exact valve and cutoff design.
I prefer to design the valve and cutoff exactly as it was on the old engine I an trying to recreate, but that can be tricky to machine accurately with an engine that is at a small scale.
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