Building an Oscillating Engine for my first engine

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malofix,

The traditional, "precise" way to mark up a workpiece is with a scriber. You can buy one or grind a sharp point on some other piece of hard metal. The idea is that you scratch a mark right into the metal you want to work. To help with this process, you dye the metal first with a "layout dye" (like "Dychem" here in the US, or use a "Sharpie" marker to put ink over the metal.

Obviously, the sharper and more concentrtic your scriber is the more precise your mark will be. When you are ready to cut metal, the more closely you follow the lines or points, the more precise your point will be. Many use magnifying glasses to get their cutters on target to the marks.

Backing up a step: Locating the marks is a large part of the battle, and you do what you can to do that well. Here is where you study a drawing well to determine where to measure FROM, and in some cases you have to plan a multiple-step process to get where you want with the end result. Here is also where you might use a flat surface (a Surface Plate, or a piece of plate glass, or any known-to-be-flat surface.

Your approach using a paper pattern introduces the chance or accumulating more error, although sometimes it might be necessary. For actual measurement, you should have multiple measuring tools and use them as necessary. The ruler (sometimes called a "scale") is useful directly, but in some cases you might use it to set a pair of dividers to a dimension that you then transfer to your part. If you're measuring over from an edge, you might use hermaphrodite calipers and use the built-in scriber. You also might be able to scratch a mark with regular calipers, but I don't like that approach as it might wear or bend the calipers. To transfer measurements, you need machinist square(s).

Here is where I ask you not to take offense. I like to encourage your efforts and boost your enthusiasm, but it seems you might be "getting the cart before the horse." It might be beneficial for you to study some of the YouTube videos available where you can see projects of all types being completed and where the things you have been asking are addressed in the course of those projects. There are also many good books out there that provide a good background. I realize that you may have some issues seeing videos or buying books from your location, but I think you might be able to get at least some of what you want.

I don't have many of the books myself, as YouTube has a lot to see for free: It has been worth some of my time to spend a few hours a week online as well as in the shop.

Some YouTubers I check, that you might find useful:

TubalCain, aka mrpete222, aka Lyle Peterson (American, not to be confused with the British Tubal Cain) He is a former High School shop Teacher who covers a lot of background and includes several model-engine-building videos.

Oxtoolco, aka Tom Lipton. He supervises a development laboratory for his day job, makes inventions and does jobs out of his professionally-equipped home workshop, and has authored some books on metal shop and hobby metal shop techniques. With a scientific background, he has made some videos about achieving ultimate precision and extreme precision in measurement.

(I'll leave the list at this point, as I'm sure others have their recommendations.)

--ShopShoe
 
It may help if you also understand the difference between "Engineering drawings" and "manufacturing drawings". I worked (as an Engineer) in a Design Office, where drawings were made by brain and pencil. The design was worked out on drawings, based on many calculations (for strength of parts, etc.). But often the design would require dimensions from somewhere to somewhere else that you could not directly measure - e.g. hole centre to an axis of something like a big-end. But a manufacturing drawing (for the production engineers to define the factory processes) would start with the "first datum" - perhaps a precision machined surface? - From where a series of dimensions would be generated to all the significant features, or machined surfaces, or centres, ot secondary datum, etc.
Many modellers only see and use machining drawings. These are relatively easy to follow from the first datum to all the machined bits so you should find these easy to use. But Engineering drawings take "the skill" - expertise - of a Production Engineer to translate into the dimensions you will actually use to mark a part, or to use for setting a machine. E.g. This week I machined an old calibrated carburettor part to a new dimension. Not by marking and cutting, but by setting a datum on the part to the tool, setting th the feed-dial to zero, then taking cuts to the size I wanted by using the machine dials. After each progressive cut I checked the reference dimension from datum to cut edge on the part, so I could be sure the cut was what I wanted, and to be sure I was reading the machine correctly.
All this is just a part of the fun of modelling, machining, and engineering.

E.g. The datum of a base-plate may be the datum for many parts on the drawing, in engineering terms, but each part in a stack needs to be a certain size from the interface where it joins the others... A "manufacturing datum" that needs to be used for the part drawing. Hard to teach in just a "short" post, but may help you understand where we are coming from.
Advice from Shop Shoe is very good. So start there....
Enjoy,
K2
 
Status update - After spending the week trying to cut the stock to the size for flywheel using a hacksaw, today i'm finished cutting 😓.Any advices regarding cutting stocks to the size?

I started looking through the bill of materials and i came across an air fitting, what is it and where can i find them? Or do i make them?
 
It may help if you also understand the difference between "Engineering drawings" and "manufacturing drawings". I worked (as an Engineer) in a Design Office, where drawings were made by brain and pencil. The design was worked out on drawings, based on many calculations (for strength of parts, etc.). But often the design would require dimensions from somewhere to somewhere else that you could not directly measure - e.g. hole centre to an axis of something like a big-end. But a manufacturing drawing (for the production engineers to define the factory processes) would start with the "first datum" - perhaps a precision machined surface? - From where a series of dimensions would be generated to all the significant features, or machined surfaces, or centres, ot secondary datum, etc.
Many modellers only see and use machining drawings. These are relatively easy to follow from the first datum to all the machined bits so you should find these easy to use. But Engineering drawings take "the skill" - expertise - of a Production Engineer to translate into the dimensions you will actually use to mark a part, or to use for setting a machine. E.g. This week I machined an old calibrated carburettor part to a new dimension. Not by marking and cutting, but by setting a datum on the part to the tool, setting th the feed-dial to zero, then taking cuts to the size I wanted by using the machine dials. After each progressive cut I checked the reference dimension from datum to cut edge on the part, so I could be sure the cut was what I wanted, and to be sure I was reading the machine correctly.
All this is just a part of the fun of modelling, machining, and engineering.

E.g. The datum of a base-plate may be the datum for many parts on the drawing, in engineering terms, but each part in a stack needs to be a certain size from the interface where it joins the others... A "manufacturing datum" that needs to be used for the part drawing. Hard to teach in just a "short" post, but may help you understand where we are coming from.
Advice from Shop Shoe is very good. So start there....
Enjoy,
K2
I realized today that I have been dimming my drawings incorrectly, that is, as a machinist. I have been dimming the overall dim, then dimming the individual *sections*. What I should be doing is dim the overall, then the longest and first cut, then the second longest cut and so on. This will make it so I doesn't need the calculator to do my machining. What a retard I have been. Someon pleez kik me.
 
Status update - After spending the week trying to cut the stock to the size for flywheel using a hacksaw, today i'm finished cutting 😓.Any advices regarding cutting stocks to the size?

I started looking through the bill of materials and i came across an air fitting, what is it and where can i find them? Or do i make them?
Do you have a photo of the air fitting? I would not have any idea what it is without a better description.

As for cutting stock, don't be cutting your stock till you need it unless it is so large that it needs to cut for storage or handling. How large was this flywheel piece you cut with a hacksaw? Did you get any photos of you cutting it? I would like to see that. If the piece is not too large, you can cut it with a cut-off saw. Do you have a cutoff saw?
 
Do you have a photo of the air fitting? I would not have any idea what it is without a better description.

As for cutting stock, don't be cutting your stock till you need it unless it is so large that it needs to cut for storage or handling. How large was this flywheel piece you cut with a hacksaw? Did you get any photos of you cutting it? I would like to see that. If the piece is not too large, you can cut it with a cut-off saw. Do you have a cutoff saw?

airfitting.PNG
That is what plan show.

The stock i was cutting was about 65mm thick aluminum. What i have right now is just a hacksaw, i should buy a cut-off saw if i find with a good price.
 
Maybe you can buy suitable cutting discs for an angle grinder? I have 1mm discs for steel, but you need discs for aluminium that are a softer grit... like for cutting concrete...? And a frame to mount the grinder to use as a chop saw.
Otherwise, a branch saw (electric) with a hacksaw (metal) blade... I have a cheap Germany battery branch saw that will cut 2 in Aluminium, slowly!
K2
 
Here in the USA we have a place called HOUSE OF HOSE they sell any and all hose and fittings air, water, steam you name it. Hope you can find what you are looking for..
 
Richard, I am sure you have something like that in Seattle.? I get a lot of air fittings and air hose from them for my day job {HVACR} also McMaster-Carr.
The poster from Turkey malofix may not have a place like that to shop.?
 
Richard, I am sure you have something like that in Seattle.? I get a lot of air fittings and air hose from them for my day job {HVACR} also McMaster-Carr.
The poster from Turkey malofix may not have a place like that to shop.?
Actually I live in Moses Lake, I just put Seattle so international people would have an idea where I live without having to resort to a map. Yes, even in Moses Lake you can get stuff like that. I don't know where in Turkey Malofix lives, but Turkey is a very modern country and I'm sure he could find it in one of the big cities. Even in the philippines where I live a lot, yo can find that in the big cities and Philippines is NOT a modern country--at least in our sense of the word.

Maybe I mistook your meaning? Were you talking about the "naughty" sense of the "house of hose"? LOL Those are in EVERY city.
 
Malofix , your lathe is not cutting wrong , when you turn your dial .001 that means it's removing .001 from each side of the material being turned which turns out to be the .002 that your seeing . SO just remember that each time you turn your dial it's removing 2 times what the dial says . hope this makes sense .
animal
 
Things left to do:
-Bore the cylinder. Problem: i don't have 4 jaw chuck and the smallest boring tool is 14mm(at max width) which is bigger than the cylinder diameter. What should i do?

-Make the shafts.

-Drill the base and vertical plate and try to assamble it all. Do it over again if something doesnt fit.

Apart from that my lathe frequently stops when taking cut, mostly when doig big cuts, and an orange led lights(problem indicator i guess) i think motor can't handle. What should i do? Can increase tork by adjusting the gears etc?
 
malofix,

You need a smaller boring tool. If you can't easily buy one, you can grind one if you have a grinder. My first boring tool was made from a standard HSS square toolbit. Some people save old cutters of all types for grinding into specialized tooling. You should be able to copy the profile of your existing cutter in a smaller size if you study it carefully.

"...Make a tool to make a tool to make a part to make a project."

--ShopShoe
 
malofix,

You need a smaller boring tool. If you can't easily buy one, you can grind one if you have a grinder. My first boring tool was made from a standard HSS square toolbit. Some people save old cutters of all types for grinding into specialized tooling. You should be able to copy the profile of your existing cutter in a smaller size if you study it carefully.

"...Make a tool to make a tool to make a part to make a project."

--ShopShoe
Hey, that's MY line!
 
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