Building an Oscillating Engine for my first engine

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For a simple bored cylinder, a reamer often achieves the accuracy required. But I DON'T use my lathe for parallel and round bores by holding the work-piece in the chuck, as it is not so accurate a process. My first couple of engines were made this way, on different old lathes, but I generated tapered bores due the the lathe alignment inaccuracy. I now bore with the mill-drill - mostly: as this means the tool describes a true circle, which then passes down the axis of the bore giving a true cylinder. On the lathe, it means the boring tool is mounted in the chuck/fixture in the main shaft - preferably between centres, and the work-piece is mounted on a fixture on the traverse (remove the tool post to mount a suitable bracket). Then the work-piece is traversed over the boring bar using the main carriage.
But this often means more work than using the mill-drill (making mounting brackets and aligning the part to DTIs set in the chuck or between centres), and I am lazy, so use the mill-drill as a boring machine. Perfect bores every time, with no taper, nor circular error.
And this is how true bores are made in industry.
It helps to have a good mill-drill... but my first bore was "corrected" this way using a simple pedestal drill.
K2
 
This is actually out of topic but here i go, how can i do tapered cuts on my lathe ? For pics of lathe click.
 
This is actually out of topic but here i go, how can i do tapered cuts on my lathe ? For pics of lathe click.
There are several different ways you can make a taper. You should tell us how steep the cut is and how long so we can advise you better. But there is another type of taper, it is a hand rolled cigarette, is that what you want? Just use scissors if you want to cut a cigarette.
 
search for lathe tail stock adjustment to cut taper on the lathe.
 
I made a taper-turning attachment for my tailstock for turning between centres :-
taper1.jpgtaper2.jpgtaper3.jpg
 
There are several different ways you can make a taper. You should tell us how steep the cut is and how long so we can advise you better. But there is another type of taper, it is a hand rolled cigarette, is that what you want? Just use scissors if you want to cut a cigarette.

Probably less than 45 degrees.

If the top feed-slide (with the tool-post) will rotate at an angle to the work-piece, that will cut a taper. It will have a base with degree markings on it...
K2

Nope, there is no rotating mechanism. It is a cheap chinese lathe, that's why probably.

I made a taper-turning attachment for my tailstock for turning between centres :-
View attachment 131705View attachment 131706View attachment 131707

How does it work?
 
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How does it work?
It's the same as any other turning between centres, except you deliberately introduce a difference between the headstock end and the tailstock end by offsetting one end of the workpiece away from the centre-line of the lathe. This results in the two ends turning different diameters, thereby introducing the taper between them.
 
Hi Malofix this is what Steamchick was referring to: Compound Slide – Chester Hobby Store

Called a top slide or compound slide, bigger lathes usually have them as standard but you would have to buy or make one.

On my lathe from I would use the top slide for a steep angle like 45deg
Cheers
Dave
 
Hi Malofix this is what Steamchick was referring to: Compound Slide – Chester Hobby Store

Called a top slide or compound slide, bigger lathes usually have them as standard but you would have to buy or make one.

On my lathe from I would use the top slide for a steep angle like 45deg
Cheers
Dave

That looks good, unfortunately many of the sellers dont ship to Turkey, not that there are many sellers that offer this compound slide. Maybe one day i'll try to make one myself.

Thanks.
 
Hi Malofix: I have been unable to view the "Mini-torma" Hobby lathe, to be able to answer your question.
The taper by tailstock displacement is good for a few degrees of taper on a long bar (such as Morse tapers, etc.).
The Compound slide rotation is much more suited to shorter taper - within the stroke of the compound slide.
I assume you do not have a compound slide.... (as I can't see the pictures).
K2
 
Hi Malofix: I have been unable to view the "Mini-torma" Hobby lathe, to be able to answer your question.
The taper by tailstock displacement is good for a few degrees of taper on a long bar (such as Morse tapers, etc.).
The Compound slide rotation is much more suited to shorter taper - within the stroke of the compound slide.
I assume you do not have a compound slide.... (as I can't see the pictures).
K2
Yes i dont i have one. I'm thinking to make one myself using a milling attachment(the one i talked before). If it is possible of course.

Buying a compound slide is half the cost lathe i own.

I'll be making the tools i need for years to come it seems.

Edit: I've decided to make the milling attachment and the compound slide by myself. I'll see if i can use the drill press to make light cuts to make the milling attachment and then i'll use the milling attachment i made to make the compound slide. This way i wont pay huge sums, but perpahs pay its equivalent amount of time. 😕

Edit 2: Or buy one of these Proxxon MF70s for the price of almost a compound slide.
 
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Yes i dont i have one. I'm thinking to make one myself using a milling attachment(the one i talked before). If it is possible of course.

Buying a compound slide is half the cost lathe i own.

I'll be making the tools i need for years to come it seems.

Edit: I've decided to make the milling attachment and the compound slide by myself. I'll see if i can use the drill press to make light cuts to make the milling attachment and then i'll use the milling attachment i made to make the compound slide. This way i wont pay huge sums, but perpahs pay its equivalent amount of time. 😕

Edit 2: Or buy one of these Proxxon MF70s for the price of almost a compound slide.
Well, I applaud you that you will make your own tools. After all, that is really what machining is all about: Making tools to make the tools that you will make the parts with. I wonder, however, what tools you already have? I know you are bootstrapping, and I always applaud someone who picks him/herself up by their own bootstraps and has the ambition enough to get off the go**amned couch and DO SOMETHING fun and useful! So, do you have a welder? That would help in certain situations. Or do you have a friend who has tools you may borrow? I know you have a drill press, that is almost an absolute necessity, altho' one could get away with a simple electric drill for most operations. How about a grinder? what kind of saw do you have?

Do you have access to a school or shop that has larger tools like grinders, or a mill?

Now for that Proxxon you are drooling over. I could not find the price for that in about 10 minutes of search--I am VERY wary about any company which hides the price tag. I have, in fact, had the experiecne, at least once, wherein a company kept the price hidden till you checked out, after you gave them your name, eddress, bank numbers--all that, and THEN you got the outrageous price! (The Chinese try this trick, to hide the price as long as possible sometimes.) I know those Proxxons are expensive, But they also have a very good reputation, even so, my recommendation is to build your own milling attachment. However, I would certainly NOT build that first--I would build the compound slide first. If you have a welder you can sort of follow the method in the utube vid in which the youngster builds his own clever lathe, carefully adapting his method for making the compound slide to the tools YOU have in which you could build one yourself. I thimpfks that the most difficult part to build would be a quality screw and nut. The bevelled parts would present a challenge also.

If you do not have a welder, you can certainly use screws or bolts.

HOwever, if you choose to build a milling attachment first, (really, it's sort of a toss-up which you choose to make first), there are some easy ones to make that use no bevels, just slides and bolts. One of the old magazines has a drawing of one. If you are interested, I will try to find it.
 
Well, I applaud you that you will make your own tools. After all, that is really what machining is all about: Making tools to make the tools that you will make the parts with. I wonder, however, what tools you already have? I know you are bootstrapping, and I always applaud someone who picks him/herself up by their own bootstraps and has the ambition enough to get off the go**amned couch and DO SOMETHING fun and useful! So, do you have a welder? That would help in certain situations. Or do you have a friend who has tools you may borrow? I know you have a drill press, that is almost an absolute necessity, altho' one could get away with a simple electric drill for most operations. How about a grinder? what kind of saw do you have?

Do you have access to a school or shop that has larger tools like grinders, or a mill?

Now for that Proxxon you are drooling over. I could not find the price for that in about 10 minutes of search--I am VERY wary about any company which hides the price tag. I have, in fact, had the experiecne, at least once, wherein a company kept the price hidden till you checked out, after you gave them your name, eddress, bank numbers--all that, and THEN you got the outrageous price! (The Chinese try this trick, to hide the price as long as possible sometimes.) I know those Proxxons are expensive, But they also have a very good reputation, even so, my recommendation is to build your own milling attachment. However, I would certainly NOT build that first--I would build the compound slide first. If you have a welder you can sort of follow the method in the utube vid in which the youngster builds his own clever lathe, carefully adapting his method for making the compound slide to the tools YOU have in which you could build one yourself. I thimpfks that the most difficult part to build would be a quality screw and nut. The bevelled parts would present a challenge also.

If you do not have a welder, you can certainly use screws or bolts.

HOwever, if you choose to build a milling attachment first, (really, it's sort of a toss-up which you choose to make first), there are some easy ones to make that use no bevels, just slides and bolts. One of the old magazines has a drawing of one. If you are interested, I will try to find it.

Thanks for the commends. No welder unfortunately. I got the lathe, drill press, grinder(also which i should make a tool rest for), taps and such other small or hand tools. Thats about it currently. I can have access to a nearby shop but that would be limited. Like i dont know how to operate a mill and they probably wouldnt let me use it without supervision, which might be a time problem.

The proxxon mill is about 310$ here. I'd prefer bolts and screws for simplicity's sake, but i'll see if i can use the shop for mill and welder. One thing i don't know is what are the critical points about compound slide. Probably the tool holder height, what else? Which material to use? I'd love to have dimensions for that sieg c1 compound slide if anyone got it.

It would be great if you can find that drawings.

Thanks.
 
Thanks for the commends. No welder unfortunately. I got the lathe, drill press, grinder(also which i should make a tool rest for), taps and such other small or hand tools. Thats about it currently. I can have access to a nearby shop but that would be limited. Like i dont know how to operate a mill and they probably wouldnt let me use it without supervision, which might be a time problem.

The proxxon mill is about 310$ here. I'd prefer bolts and screws for simplicity's sake, but i'll see if i can use the shop for mill and welder. One thing i don't know is what are the critical points about compound slide. Probably the tool holder height, what else? Which material to use? I'd love to have dimensions for that sieg c1 compound slide if anyone got it.

It would be great if you can find that drawings.

Thanks.
You have to have the strength, after all the removal of the inside material, that the remaining bed will be able to manage the stresses of machining. With that little lathe you have, you will not need all that much. The top of the compound has to have enough room to machine a method to hold the tool holder--you could use a couple of methods for that. AND the underside needs the room for the screw to travel and the placement of the nut. I'm sure you could find drawings for this, maybe not with dimensions but concept for sure. After all that, yuou want the thing to be as low as possible to be able to get a spinning work piece of the largest size over that compound. You have to balance all those concepts together to get your end result.
 
Thanks for the commends. No welder unfortunately. I got the lathe, drill press, grinder(also which i should make a tool rest for), taps and such other small or hand tools. Thats about it currently. I can have access to a nearby shop but that would be limited. Like i dont know how to operate a mill and they probably wouldnt let me use it without supervision, which might be a time problem.

The proxxon mill is about 310$ here. I'd prefer bolts and screws for simplicity's sake, but i'll see if i can use the shop for mill and welder. One thing i don't know is what are the critical points about compound slide. Probably the tool holder height, what else? Which material to use? I'd love to have dimensions for that sieg c1 compound slide if anyone got it.

It would be great if you can find that drawings.

Thanks.
1639164346319.jpeg
here is an examle that you could probably work from. I cannot find eithr the thread in HMEM in which I posted the 3D drawig of an attachmet which used no slanted cuts, it only bolted slides together. I was going to try to build this but ended up getting one by othr means. I thimpfks that the drawing I have is stuck in a dead computer.
 
View attachment 131807here is an examle that you could probably work from. I cannot find eithr the thread in HMEM in which I posted the 3D drawig of an attachmet which used no slanted cuts, it only bolted slides together. I was going to try to build this but ended up getting one by othr means. I thimpfks that the drawing I have is stuck in a dead computer.
Malofix There is a free plan for a vertical slide on the model engines website that you can download:

https://www.model-engineer.co.uk/news/article/free-plan-cross-vice-to-vertical-slide/22255/
 

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