Garden Railway Forum

I was reluctant to mention the use of glass as it is not the easiest material to cut accurately. Being a picture framer (retired) I have been cutting glass for years and there is a skill involved to get clean edges and precise measurements, certainly not a simple as cutting styrene.
A handy trick to know is to use White Spirit (Turps) on your cutting tool to ensure a good lubrication of the wheel. Also, NEVER go over the same cut twice, this will damage the wheel beyond use.

Peter Butler wrote: ↑Thu Aug 20, 2020 10:08 am I was reluctant to mention the use of glass as it is not the easiest material to cut accurately. Being a picture framer (retired) I have been cutting glass for years and there is a skill involved to get clean edges and precise measurements, certainly not a simple as cutting styrene.
A handy trick to know is to use White Spirit (Turps) on your cutting tool to ensure a good lubrication of the wheel. Also, NEVER go over the same cut twice, this will damage the wheel beyond use.

That's useful info, thanks Peter.
One of my holiday jobs many (many) years ago was in a builders' merchants. I was taught how to cut large sheets of glass on a flat table. We placed a couple of matches under the scored cut line and applied gentle pressure either side.

I must admit that cutting glass was probably my least favourite job, closely followed by unloading paving slabs by hand from the delivery lorry.

Rik

Still working on the roof of the Boneworks but, while waiting for the ridge tiles to print out, I put together the beam engine. . . .
I haven't bothered too much with the finish as it will be located inside the engine house and so only partially visible. Of course it still needs painting but I wanted to see how it worked with a motor. It's still a bit too fast, so I'm going to investigate slowing it down. I have one of those miniature geared motors so might remodel the motor housing to take it instead of the bog standard 3v motor.

.
Rik

Thats good Rik.
As you say, a bit fast, at that speed it lacks the 'majesty' of the real thing. If you are using a 3v motor, what is it like at 1.5v?

philipy wrote: ↑Tue Aug 25, 2020 6:20 pm Thats good Rik.
As you say, a bit fast, at that speed it lacks the 'majesty' of the real thing. If you are using a 3v motor, what is it like at 1.5v?

Hi Philip
I'm powering the 3v motor from a single 1.2v rechargeable cell ..... so not got much leeway left.

Rik

ge_rik wrote: ↑Thu Aug 20, 2020 12:32 pm That's useful info, thanks Peter.

Seconded. I'll bet the edges of my cut pieces were a bit painful to look at with experienced eyes.

Rik, that engine's coming up nicely. Must agree regarding the speed. I've seen videos of live steam beam engines running on air at such speed, that one half-expects them to fly apart. Looks very wrong, but I suppose is one way to test the build quality!
Looking forward to seeing your revised drive arrangement.

Regards,
Aaron

stupid question time...
I assume that big round vertical thing is the cylinder. If so how come it has a big hole in the side?

RE the motor speed, if the gearbox idea is too hard, how about an electronic solution? An esc or PWM using a Picaxe.

gregh wrote: ↑Wed Aug 26, 2020 6:25 am stupid question time...
I assume that big round vertical thing is the cylinder. If so how come it has a big hole in the side?

RE the motor speed, if the gearbox idea is too hard, how about an electronic solution? An esc or PWM using a Picaxe.

Yup, it is the cylinder. The designer of the kit seemed to think it was a good idea to make the cladding removable so people can see the piston going up and down. Not sure why.

I've sent off for a Pwm motor controller for £2.85, which seemed good value.

Rik

gregh wrote: ↑Wed Aug 26, 2020 6:25 am stupid question time...
I assume that big round vertical thing is the cylinder. If so how come it has a big hole in the side?

RE the motor speed, if the gearbox idea is too hard, how about an electronic solution? An esc or PWM using a Picaxe.

Rik,
I was just browsing Thingiverse and I noticed this comment on the beam engine, "Just for information, If you have an old Braun electric tooth brush laying around, the motor from it fits perfectly into this Beam Engine." Don't know if that might help?

philipy wrote: ↑Thu Aug 27, 2020 4:06 pm Rik,
I was just browsing Thingiverse and I noticed this comment on the beam engine, "Just for information, If you have an old Braun electric tooth brush laying around, the motor from it fits perfectly into this Beam Engine." Don't know if that might help?

Thanks Philip
I tinkered around with one of those tiny geared motors (I bought three of them a few years ago - just in case). I tried connecting it via a pulley to the end of the crankshaft but struggled to get the tension on the belt right - too tight and the friction on the shaft increased too much, too loose and it slipped.

In the end, I drew and printed a cradle to hold the motor inside the original motor clip. The speed from the motor shaft alone was too slow, so I found a wheel off a cheap plastic toy which gives a far better speed when bearing on the flywheel. I've had to move the position of the motor mount but I'm now much happier with the speed - slow and ponderous. I might increase the speed a little by adding another cell and then use the PWM controller to fine tune it.

I'm just painting the model, so will make a video when it's done.

Rik

What about a clock motor Rik? You might actually need to gear it up a bit!
https://www.ebay.co.uk/itm/154029066295

Lonsdaler wrote: ↑Fri Aug 28, 2020 7:07 pm What about a clock motor Rik? You might actually need to gear it up a bit!
https://www.ebay.co.uk/itm/154029066295

Thanks for the suggestion, Phil, but I've now sorted it out with the miniature geared motor. The ex-toy-car wheel I'm using as friction drive on the flywheel isn't the most elegant solution but I can hid that easily with a strategically placed barrel or step-ladder.

I think the speed is much more appropriate and with the PWM controller can tweak it. All I need to do now is finish the boneworks so it can have a home ..... . . .


Rik

Well done Rik, that has worked out OK with the new control system. Printing marks will go unnoticed once in position, perhaps some steam sounds could help to add atmosphere?

Lovely Rik, well done.
FWIW, I think the speed looks about right at the beginning, before the big hand in the sky twiddled the knob.

philipy wrote: ↑Fri Aug 28, 2020 8:51 pm FWIW, I think the speed looks about right at the beginning, before the big hand in the sky twiddled the knob.

I did wonder, still it's comforting to know I have a knob to twiddle when I get the urge.....

Peter Butler wrote: ↑Fri Aug 28, 2020 8:47 pm ........, perhaps some steam sounds could help to add atmosphere?

I was considering adding a sound module. I have one of those MP3 player cubes to spare. Just need to find the right sounds. If it's open, I might take a trip to the boneworks in Stoke - just need to find out when they're next firing up their engine...

Rik

ge_rik wrote: ↑Fri Aug 28, 2020 10:06 pm
I was considering adding a sound module. I have one of those MP3 player cubes to spare. Just need to find the right sounds. If it's open, I might take a trip to the boneworks in Stoke - just need to find out when they're next firing up their engine...

It looks as though he modelled the printed machine on a Stuart beam engine model? I found these videos on YT and it appears that the most noticeable noise is actually just a rythmic knocking. Don't know if you can copy a sound clip and just repeat it?

It also looks as though in practice they seem to run faster than we've been thinking, but that may not necessarily be the case if it was scaled up to real life?

https://www.youtube.com/watch?v=PIn1tG2WSeo
https://www.youtube.com/watch?v=pSXgm8AlniQ
https://www.youtube.com/watch?v=8IF7M1B7RN8
https://www.youtube.com/watch?v=6H-JYSp99eU
https://www.youtube.com/watch?v=JTZikEUzwLo


https://www.youtube.com/watch?v=FnHICHT2wZE

Knob twiddling aside, that's a very good solution Rik. Have you used one of the "12v LED dimmer switches" off ebay? Not bad value for about £2-3 each. I'm currently using 4 in a non railway related project. The last time I built one from a Velleman kit, and it was not that cheap!

ge_rik wrote: ↑Fri Aug 28, 2020 8:28 pm I think the speed is much more appropriate and with the PWM controller can tweak it.

The website for the Etruria Industrial Museum says the engine was built in the 1820s. Marine engines of the period are usually quoted as running at 20 rpm and the much older Whitbread beam engine in the Powerhouse Museum in Sydney is also quoted as running at 20 rpm. Easiest way to visualise that speed is the beam should take 3 secs. to move up and back down again.

As Philipy said, these old beam engines don't make much noise when running. They use a condenser, so there's no exhaust noise and the working pressure and speed is so low that there's little mechanical noise.

As I recall the only noise the one in Sydney makes when in steam is a quiet wheezing noise and there's a click from the valve driving mechanism as it reverses the valve at the end of the stroke.

Regards,
Graeme

GTB wrote: ↑Sat Aug 29, 2020 4:38 pm As I recall the only noise the one in Sydney makes when in steam is a quiet wheezing noise and there's a click from the valve driving mechanism as it reverses the valve at the end of the stroke.

I'll just record myself after I've been for a bike ride ......

Rik

Thanks guys
I really appreciate the effort you've all put in to research the background to this little beam engine. I must admit, I do like the ponderous nature of beam engines - the have a certain majesty .....

Rik