My First Stationary Engine

[Ron LadenParticipant @ronladen17547]

Thanks Geoff/Jason, up early this morning and I lapped in the faces.

Something that has surprised me is the recommended compression spring, its quite a strong little spring 4.3mm i/d 0.7mm wire with 10 coils in 12.7mm length. Anyway I dont have one to that spec but I have one which matches the diameter and the wire but is more open with 7 coils per 12.7mm, I will give that a go it is adjustable of course.

Ron

[JasonBModerator @jasonb]

A lot will depend on what you do with the engine, if just running for display on a few psi than a light spring will be OK. Once you start to put the engine under load which required a higher pressure there is a greater risk of the air taking the easy option and lifting the cylinder off the portface rather than pushing on the end of the piston so a stronger spring will keep it held in place.

[Ron LadenParticipant @ronladen17547]

Thanks Jason, it will only be running for display so I think the spring I am using should be ok.

I turned up a temporary plinth/work stand to save it lying around or having to prop it up on the bench.

[Ron LadenParticipant @ronladen17547]

Impatient as I am and having not yet received the steel for the flywheel as well as being mad keen to see if the engine would run, I searched the shop for something to fashion a temporary test wheel. The only thing I had was a short piece of 3 inch diameter 6082 so I used that, its not very true but as it turned out it served its purpose.

The good news is the engine ran straight away with no problems and I have made no adjustments to it, as it is in the video is how it ran from the start. I havnt shown it at its top end speed as it would take a walk across the bench with out it been held down. This is all new to me but I was surprised at the bottom end speed which I thought quite slow for a aluminium flywheel, it will be interesting to see if that changes with a steel wheel.

Anyway it goes without saying I am really pleased with it.

p.s Apologies for the poor quality video, the original is much better dont know what happened there. 

 

 

Edited By Ron Laden on 10/02/2020 13:33:17

[geoff walker 1Participant @geoffwalker1]

HI Ron,

Looks great to me and running well.

Mine dances around at high speed, needs a heavier base.

Next engine I made had a large 1/2" steel plate base, no chance of that going for a walk!!!!

Post again Ron with new flywheel

Atb Geoff

[JasonBModerator @jasonb]

Runs well Ron though next time put the sound on so we can hear the chuff, chuff noise.Another option to stop the engine jumping about would be to add some counter balance to the crank of flywheel, maybe something to consider for your second engine now you have got the bug

[Ron LadenParticipant @ronladen17547]

Thanks Geoff/Jason and thanks for your help, much appreciated.

I am really chuffed with it I imagined a lot of fiddling and adjusting so it was a surprise when I turned on the air, gave it a flick and off it went..

I would like to build in some counter balance to the steel flywheel if possible but how do you calculate how much or is there an element of guesstimation..?

A video below with some sound, excuse the sound of someone taking their last breaths its the airbrush compressor which is an on demand type. Although it provides a constant air pressure it switches itself on and off constantly.

 

Edited By Ron Laden on 10/02/2020 17:07:51

[Ron LadenParticipant @ronladen17547]

Jason you mentioned a second engine well I think there will be.

The class 22 body I am going to build in the old workshop but not until the weather picks up so at least a month I guess. I could do more on the T/E but I really want the 22 finished first then concentrate on the traction.

So I am looking for a project any suggestions would be welcome.

I am thinking something a bit more advanced than the little oscillator but not too complex or long winded. Made from bar stock with the exception of the flywheel of course. Maybe a bit larger, would even consider scaling something up and obviously something that will fit the lathe and the little mill.

Ron

Edited By Ron Laden on 11/02/2020 06:11:19

Edited By Ron Laden on 11/02/2020 06:12:35

[JasonBModerator @jasonb]

It is possible to weigh the various moving parts and work out what the balance weight should be but on something like this trial and hopefully not too much error will do. If you are making the flywheel as per drawing then I would think about leaving one of the holes smaller and then testing the engine gradually opening it up until you get the balance. This may not suit the eye so the other option would be to add some weight to the rim much like you do a car wheel and then blend it in with filler and paint over the top.

I should think you could manage my Jowitt described on here or even the Muncaster, or there are Stew Harts "Potty" series of engines.

[DanielParticipant @daniel]

A superb and inspirational thread Ron.

Well done,

ATB,

Daniel

[geoff walker 1Participant @geoffwalker1]

HI Ron and well done'

With regard to balancing the engine.

The flywheel needs to be as balanced as possible but without a balanced crank as well I can't see how you will ever have a good static balance and without that never have a good dynamic balance.

To aid balance the crank is better with a crank web such that when you rotate the engine by hand it will NOT settle in the same place every time. The web can be adjusted for size by making it larger or smaller or adding weights to the web

Three of the simpler muncaster engines have no balanced crank.?

Just my thoughts Geoff

[Ron LadenParticipant @ronladen17547]

Thanks Daniel, I surprised myself how well it has gone, especially the running, still got the flywheel and plinth to make to finish the engine.

Geoff, thinking about the balance I dont think I will worry too much about it, I will get a bit of weight into the plinth and I wont be running the engine flat out. I think it better run at just below mid speed or slower and the engine is quite stable at those speeds even on the temporary lightweight plinth.

Ron

[Ron LadenParticipant @ronladen17547]

Jason,

Once I have the oscillator finished I am going to have a go at the Jowitt engine, I really like the look of it especially the cylinder.

I have been through your build thread and the drawings and I am happy with it and I think I have most of the tooling thats needed.

I happen to have some 2 inch x 1/2 inch 6082 for the side frames so thats a start. I am thinking aluminium for the cylinder which I think you said is an option and the faceted cuts method went well on the T/E cylinder so I should be ok with the shaping.

Looking forward to making a start.

Ron

 

Edited By Ron Laden on 11/02/2020 10:40:38

[JasonBModerator @jasonb]

Yes aluminium will be OK. There is also the option to make it smaller, I did one at half size and 3/4 size would be about what the original was.

Most if not all of the hit and miss engines that I have made don't have any form of balance to the crank and even my 2" Fowler does not all as per full size but they do have balance weight or hollowed out parts to the flywheel to provide the counter balance.

Edited By JasonB on 11/02/2020 13:02:07

[Ron LadenParticipant @ronladen17547]

Thanks Jason,

I think I will go with the size as per your drawings and build thread.

Watching the video it does look a very good runner and the sound is nice to, I checked on Reeves website and the Perseus flywheels still seem to be available.

Ron

[Ron LadenParticipant @ronladen17547]

Change of plan for the flywheel I am not going with machining up a steel version I think the engine deserves better than that. I have ordered a 3 inch x 1/2 inch 6 spoke cast iron wheel from Stuart, will look much better I think. Also I am not much of a fan of engines mounted on a wooden base but that's just me. I know numerous engines have been presented like that over the years and it was probably the excepted method but I much prefer to see a nicely shaped/finished metal plinth/base. I will probably get shot down in flames now.. but its just my preference.

Ron

Edited By Ron Laden on 12/02/2020 06:38:15

[PeroParticipant @pero]

There is no right or wrong.

I like wood … and metal. It's a matter of personal preference and what the builder thinks suits the particular model best.

A well finished base adds an enormous amount to the presentation of a model engine.

Pero

[JasonBModerator @jasonb]

I was thinking about the question of balance and having just watched the video again that has confirmed what I was thinking. The movement is not so much caused by the piston going up and down but by the cylinder moving from side to side, you can see the base of the engine moving in one plane when it speeds up about half way through the video.

More weight in the bottom would help such as changing the aluminium base to steel or iron and then punch out a couple of thin rubber discs and glue to the underside so it is less likely to slide about and also saves marking the shelf/table/display case.

Good call on the cast flywheel

[Ron LadenParticipant @ronladen17547]

Thanks Jason,

Yes watching the video I see what you mean, I am thinking of a 100mm base probably round in shape and a reasonable thickness to elevate the engine so steel I guess should be heavy enough.

I am hoping the Stuart flywheel is like their website picture, it looks a very clean casting but we will see.

Out of interest I made a materials list from the drawings for when I start the Jowitt and its not too bad, I have most it. Need some bronze, the flywheels, O rings and a lump of alu for the cylinder and I should be about there.

[JasonBModerator @jasonb]

I've used the Stuart 10 series flywheels for a few engines and they have all been quite good castings.

[Former MemberParticipant @formermember19781]

[This posting has been removed]

[Ron LadenParticipant @ronladen17547]

Posted by Bill Chugg on 12/02/2020 15:24:29:

You should be pleased with it Ron.

In the clearout of all my models, I recently passed on an original Chelston Model Engineering version, and it went really well. Made from a kit of parts by someone other than myself.

Bill

Edited By Bill Chugg on 12/02/2020 15:25:51

Hi Bill, yes I am pleased with it, turned out better than I expected, will be good to see a nice flywheel on it.

Ron

[geoff walker 1Participant @geoffwalker1]

Hi Ron,

Yes 10/10 for the flywheel, stuart castings are ex quality, machine beautifully and will look great on your model!!!

Nice work, looking forward to final pics and video.

Geoff

[geoff walker 1Participant @geoffwalker1]

Hi Jason

Most if not all of the hit and miss engines that I have made don't have any form of balance to the crank and even my 2" Fowler does not all as per full size but they do have balance weight or hollowed out parts to the flywheel to provide the counter balance.

The above paragraph, interesting, what I would describe as lateral thinking.

Are you saying that if one component is out of balance, the crank, you also make the flywheel out of balance to counteract? Would the weights/hollows on the flywheel be at roughly 180 degrees to the crank pin and big end.

I can see the logic and how it would work, but like I say lateral thinking and very interesting.

Geoff

[JasonBModerator @jasonb]

That's it. The hollow is on the crank pin side of teh flywheel and the weight on the opposite side, couple of examples

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