Elmers Mine Engine

[Bogstandard]

There has been a great lack of engines over the last week or so, so I thought I would show how I am getting on with my mine engine. I don't normally show until the end but even when this one is finished, there will be more to come.
The first pic shows the rough cut start with my new found skill in turning taking prominence.

This next one shows how far I am up to now. I bonded the two bottom plates together and machined it as one solid base, I think it gives a more 'casting' look.

I have decided to put as many ballraces in this one as I can, because this engine will actually be doing work. So a lot of the bearing areas will have to be modified slightly to accomodate them.

You will notice in the background a rough ali plate with what looks like circles on it. I am just experimenting with a new milling cutter and hope to use the technique on this engine at a later stage. Also I am not really happy with this lightweight flywheel and I feel a nice brass one coming on.
This one will be able to be used elsewhere.

John

 

[Bogstandard]

Because this engine is going to be used for the power supply for a much larger display, and will be running for 7 to 8 hours a day, I thought that the bottom end really needed 'beefing' up to allow it to run for extended hours. Here is a shot of the bottom end with the bearings installed. I am just working on the conrod bearing.

The valve eccentric took a lot of working out, and the rod isn't going to be going out at an angle, but straight up, then thru bellcranks to its original output position.
Also the valve eccentric isn't now directly coupled to the crankshaft, but driven off the back of the flywheel via a pin. The reason for this is it will be a lot easier to retime the engine to run in the opposite direction, by just slackening the flywheel screw and turning the flywheel thru 180deg. and because of the larger radius it will be more accurate in setting the timing.

John

 

[1Kenny]

Now....now, John

I see two different flywheels. Are you making two engines?

 

[Bogstandard]

Hi Kenny,
If you read the bottom of the previous post you will be brought right up to date.

John

 

[1Kenny]

I see that now John. That is what happens when I sleep between posts. LOL
Anyway, the brass flywheel looks great. Did you make the whole thing? I think it is very pretty.
Kenny

 

[rake60]

I was expecting something impressive John.
You have already past that expectation.
Looking great!
Keep us updated.

Rick

 

[Bogstandard]

Kenny,

The flywheel was turned from a lump of brass plate as described in my tips article then onto the RT to hack out the spokes.
Everything else came from plate or brass rod.
All materials were sourced from the scrapyard, or salvaged from old jig plates from a closed down factory. Bearings come from scrap printers and old machinery, donated by friends.
Material costs up to now, about $5 to $10.
Have been making the crankshaft today, The main problem was getting a bearing that would fit. I ended up surface grinding 15 thou off each side face to get it to the right thickness. I had to 'lose' the side shields, but thats what comes of being a cheapskate and not buying bearings.

Rick,

Thanks for the compliments. Had a couple of bad days at the hospital so haven't been able to get on as I should, but now sorted and blasting on for the weekend. I'll be glad to get away from the bottom end of the engine, but it had to be done.
The engine, if it has enough power, is going to be used for showing all different types of couplings and drive trains, a few of the ideas have been 'stolen' from posts on here, and I have the word out locally for miniature couplings and unusual gear systems. But that will be an ongoing project that can be added to as things become available.

John

 

[Bogstandard]

Here is an update on the build.
I managed to get on a bit today and finished the bottom end (at last).
Everything from now on should be as designed except for a couple of small items on the valve gear.
These pics are views of the engine as it now stands. The black paint is only the primer colour, it will eventually be high gloss black.
It is now starting to look like my original vision of what I wanted for this engine.

The main problem now is that I can't wait to get it finshed and see if it runs with my mods to the valve linkage.
I have been looking to see if the control gear from Elmers horizontal engine could be fitted to this one, but the space that is available is very tight. But I do have an idea that just might work. Any help on this issue gratefully accepted.

John

 

[Bogstandard]

If you read my article on a drilling jig in the hints and tips section, I actually got to use it today.
I have been making all the round bits for the cylinder and the final job was to drill all the mounting holes.
It worked like a charm, used in conjunction with a bit of superglue, all bits fit together perfectly. It has saved hours setting up the RT.

John

 

[mklotz]

Rotary table?! We don't need no steenkin' rotary table. That's why trig and coordinate drilling were invented. (And I don't even have a DRO.)

 

[Bogstandard]

Please be gentle with me Marv,
Up until I got my RT I used to use a program I got off your site to work out the co-ords. I have got used to being lazy and let the tooling do all the work for me, besides the fact the old grey matter isn't what it used to be. Even with a RT I found I was getting confused when I was making the flywheel trying to remember all the different cutter positions and offsets.
Some of us are slowly losing our faculties, whereas it seems like you are gaining on yours.

John

 

[Cedge]

John
I'm loving what I'm seeing. I'll have to agree with the others, you've got a marvelous engine going together there. I, for one am, enjoying the chance to see it come together, to the fullest. The spiral columns are a master stroke and you know how much I like shiny metal...(grin). You, sir, are proving to be one prolific builder.

I'm still looking at the Liney engine designs with an eye toward doing something a little different, but I'm nowhere near ready to put anything in metal yet. Lots of ideas still being sorted but not many chips.

Steve

 

[Bogstandard]

Thanks Steve, glad you like it.
I am rather prolific on the building side, but there is a reason for that, as I explained in my personal post to you. Just got to keep going.
I am also lucky in that I have 24/7 at my disposal in the workshop, plus a wife that, as long as I am still breathing, doesn't mind what I do.
I think I might have cracked the engine reversing problem, just a matter of getting it from my brain cell into metal, very accurately.
I was looking at the Liney Halo radial, but until he comes out with all the notes for it I won't bother. Apart from a very few bits it is just repetitive machining, which I don't mind.
Hope to have all the top end machined up today except for the valve gear.

John

 

[Bogstandard]

Right, here we go again,
Managed to get most of the top end made including standard and piston but then hit a slight problem of how I was going to ball race the top of the conrod. I have a theory about ball races, if you can't hide them, make a feature of them, so that is what I am doing.
Because there are a few extra bits going into this conrod, things needed to be kept exact, so when it came to mounting the bearing carriers I had to make a rough jig out of ali plate, a bit of ali tube and some silver steel. This is shown on the first pic.

If you look carefully you can just see the flux and minute loops of silver solder. Thirty seconds later it was all over and done with. The reason for the ali tube rather than solid was to try and keep the heat loss to a minimum.
This next pic shows it after a bit of polishing and having the bearings fitted, all line up perfectly.

In the background is the cylinder and standard, not painted but coloured up with felt tip to see what the contrast points look like, and I think I will be going with this scheme. The felt tip just washes off with a bit of spirits.

John

 

[LeChatNoir]

I love how you are giving as much effort to aesthetics as you are to the mechanics of this engine. Really a class act, sir.

I’ve got this old Singer treadle sewing machine, and along with all the other details, the tops of the rods for the presser foot and needle carrier both have these tiny little acorns on them… turned and knurled.

It seems there is so much lacking in the world today due to loss of art in the design of most things. I really believe such details touch us, even if only on a subconscious level, as we go about our routines, adding up to make our lives more pleasurable… more fun. Such things, to me, are an affirmation that I’m still human and still and alive.

Long many years from now, like my little sewing machine, your engine will still be ticking along giving great joy. Kudos and keep up the good work!!

LCN

 

[Bogstandard]

Many thanks for the compliments.
Here in the UK we are lucky in that a lot of our heritage is preserved, and a lot from the industrial revolution. When I look at these, everywhere you see little snippets of real caring craftsmanship. It seemed at that time if you did a job well you would add a little bit of embellishment, just to lift it above the norm. This is a thing that is missing in this modern day, everything is just clean lines with a minimalist look with no individualism.
So when I take on a special little project like this I tend to make it my own, and totally unique. Steve (Cedge) is another that seems to follow this line of thought, he has done a wonderful job of transforming a standard elbow engine into something beautiful to look at.
They don't normally run any better, just look different.

John

 

[Bogstandard]

A couple of up to date pictures.
This first one is showing how the conrod ballraces have been covered up and protected fom the 'elements'. I have also basically bolted the top end together to see if there is any binding, s-m-o-o-t-h as a baby's bum, so no worry on that score. Starting to feel happy now as most of the hard bits are done. I have even managed to squeeze my logo onto the centre of the crankdisc.

This next pic is just showing a side view. The flywheel is off for heavy engineering modifications, I have decided to go for a slip eccentric to allow easy reversing of the engine, and to upset Marv I am going to mount it into my RT and machine a 180 degree 2mm slot on the inside edge of the centre boss, this will allow me to turn off the air, turn the flywheel 180 degrees in the direction I want it to go, then when the air is turned back on the engine should start in the direction I want it to go, a very simple solution. To allow me to quickly turn off the air I was looking thru my salvaged stash and found a nice control valve (in the foreground of the second pic) so I am hoping to modify it to use on this engine. 180 degree turn full on/off with speed control over the range.

The remainder of the hard bits are now going to be taken on, the valve gear, plus trying to get it connected to my modified eccentric bits (I'm still talking about the engine, not me).

John

 

[rake60]

The basic design on this engine is incredibly smooth and friction free.
With the bearing and your skills I can't wait to see this one run!

I believe this will be your turbine engines 180 degree opposite.
The turbine was spinning fast enough to scare me. I have a feeling this
one will run slow enough to scare me even worse. :wink:

This is the first thread I check when I log on.
I want to see it DONE!!!! HOW SOON JOHN?
I can't believe I typed that!

Of course I'm kidding, but I AM a little anxious here......

It sure is looking great! Amazing craftsmanship!

Rick

 

[Bogstandard]

Hi Rick,
I have to disagree with you on the amazing craftsmanship bit.
It is just different from the norm. All the people on here have the ability to do something like this, you just need a bit of forward vision to get to where you want.
Where I am lucky is that I have the ability to design and make as I go along. A thing I picked up many years ago when in the computer peripheral business, everything was moving that fast in those days if you didn't do it that way you were left behind.
I started on the valve gear today, so hopefully, if all goes well I just might get a bit of air on it over the weekend, but I won't promise anything as I have a few appointments which might just put me out of it for a few days. To completely finish, that is paint, polish and mounting maybe another 10 days. Which has put it about right for my one engine per month build program.
What I really want from this engine is not slow running but POWER, if it means modifying the piston setup, I will do. If I have to resort to putting rings in the slow running characteristic with blow away with the wind as the friction involved means that it has to run at a higher speed just to keep it running. I will suck it and see before making any decisions.

John

 

[Bogstandard]

This valve gear bit took a lot longer than I thought, plus I had to take a full day out, but I am now catching up fast.
I will just explain what and why I am doing this modification to the valve gear drive train. The first main bit is that I want to easily reverse this engine. As built from the plan, it will only rotate one way, to get it to rotate the other way the eccentric has to be retimed in the opposite direction by 180deg.
The other reason is that I just didn't like the way it looked.
This sketch explains what I am about to do.

This next pic shows how far I have got to achieving this solution.

The main criteria when doing a mod like this is to eventually end up with the linkage operating at the steam chest in exactly the same way as the original, so all the drilling has to be spot on, so all the critical drilling is done first and then the bits shaped up afterwards. This is the stage I am up to. You will also notice that the flywheel has had a 180deg slot milled into it, this is for the slip eccentric. If you want to know what a slip eccentric is and how it works, it is explained here, it is shown for a model loco but it does explain it well.
http://roundhouse-eng.com/ss04.htm
I will be able to do the same thing but all I will need to do is stop the engine, turn the flywheel thru 180deg in the opposite direction and restart the engine.

John