Garden Railway Forum

I've finished moving into my new house and building a proper work-bench in the basement, and ready to start a new project.

I was pretty impressed with Mr. Bond's little "momentum van", especially when I saw it in action in a couple of videos. His track has lots of bends, and the little wagon almost made it look like his manual-controlled locomotive were being driven by someone.

I've decided, for fun, to make one as my next project. After contacting Mr. Bond (of the DVLR) I found out how he did it, and I've ordered a "Zecar" flywheel-toy as well as a IP engineering generic goods van.

Stay tuned as I document the construction of this wagon. Unfortunately I don't have much of a railway (about 15 feet of track on the workbench at the moment) to test it on, but I am hoping to make a before and after video so we can see how it all works out!

Have you got a link to Zach's original post about the momentum van? I've tried a search but not been able to uncover it.

Rik

Hullo,
It is mentioned in the DVLR thread and in the test video I did but not much more than that on here as I wrote it up for Garden Rail.
http://gardenrails.myfreeforum.org/ftop ... sc-555.php

Has it been published in Garden Rail yet? If so, which issue? I have a subscription but I'm still wading through all the past issues!

246 page 30.
http://www.exacteditions.com/read/garde ... 41274/30/3

I wonder how I missed that. I have that issue right on my iPad. I was in Switzerland doing flight training at the time it came out, so I must have missed the entire issue. Good- I have a whole magazine to read that I didn't know about. Bonus!

Thanks Zach, looks great, I my have to try it myself sometime - my tight-ish curves and steep grades don't always make for smooth running...

Whilst looking through the GR in your attachment I came across a review of a little £3 booklet about preparing CAD drawings for laser cutting too - result! I've placed an order already...

Cheers,

Andrew.

Well men, I've got some work done on the momentum van, I'm afraid I've done my usual slap-dash job of assembling kits...

Mr. Bond, on his wagon, made the wagon's original journal-boxes functional, with only the weight of the flywheel device being carried by the device's bearings. The weight of the wagon itself is still on the kit's bearings, which are much better bearings. I found it a challenge to mount the axle boxes so that they were perfectly in line with the bearings on the flywheel device, and were as free-running as possible. I finally got it all lined up OK after lots of cross muttering and pulling things apart and re-gluing them:





Cutting the hole in the wagon floor was really the only modification to the kit. I'm not sure how I feel about this new MDF stuff: it's much easier to cut, but even after drilling pilot holes and using a new sharp saw, the hole looks like it was chewed out of the floor by a beaver.

The axles on the "Z-car" toy are almost exactly the same length as the original IP engineering 45mm gauge axles. I ended up however, gluing the wheels to the axles first, so I could use my Roundhouse back-to-back measuring gauge to make sure they were exactly the right distance apart on the axles. Then, I fitted the sole-bars with pre-glue axle boxes to fit. They are perhaps half a millimetre farther apart than they would be on the un-modified wagon.

Next, I fitted the centre buffers and piled up some wood on the wagon to create a little platform. I'll use this to test the wagon behind the engine, in order to figure out how much weight is best before I build the van body.

Well, I've just completed testing the basic chassis. I can say right now I am AMAZED at how well it works. I weighed the wagon down with a drill-bit set, and at this weight the loco can get it going without any wheel-slip. The locomotive can just about overpower the flywheel, but not quite, so when the van wheels actually slip on a bit of greasy rail, the train only lurches forward a tiny bit before the wheels grab again. Same with when the locomotive's wheels do slip, it only slips a quarter turn or so and then gets to work again.

I am very impressed. The engine's performance on my little test-track is completely different with this wagon attached. It doesn't make very much noise, what whirring sound it does make is masked by the engine's chuffing, and what amazes me the most is that you can set the regulator once and the engine will just slowly accelerate to whatever speed the regulator setting equates to. The flywheel also seems to limit the speed, so the engine just chuffs along steadily without accelerating to that speed where the exhaust beats all blend together into a buzzing sound. This is incredible. Zach you should make and sell these for profit!

I posted the video in the "videos" section, but here is the link:

http://gardenrails.myfreeforum.org/about9670.html

Hi Keith,

Mr Bond's wagon looks like a great idea, I must try one. For anyone here in the UK the B&M Discount stores are selling Postman Pat Greendale Rocket toys for £6.99 which are friction powered and will be a lot less work to convert that the electric version I altered. I bought this one yesterday.



Their motor is screwed together and just 24 mm wide and has mounting brackets! Two projects in one?



Regards Tony.

Looking at both the wheelbase and the small size of the mechanism it seems possible that a slate wagon or 2t mineral wagon could become a "momentum vehicle" - I guess the issue would be how much weight is required and whether it could be achieved using a smaller vehicle... Any thoughts?

Thanks for the video Keith - I'm increasingly tempted!

Andrew.

Hi guys,

Is this the product we are talking about?

http://www.amazon.co.uk/Kikkerland-1589 ... B000L2JVKW

That's the one.

Thanks Keith.

I have all the bits needed to have a go at one of these so will give it a try before investing in SSP slomos

Obviously the "slomo" device is higher-quality and higher-performance. You can put one of them in a wagon or tender as well as on the locomotive itself, as Chris Bird has demonstrated in his video series.

For me the decision to be made is whether to have the device mounted on an engine or in a wagon, with various pros and cons to each approach.

If it's mounted in a wagon, then it's the train itself that has the "momentum", not just the locomotive, so, especially if you have radio-control, I would think the driving experience might actually be more realistic, since you would now have to contend with wheel slip, and take into account all the other factors that real driver would with a "heavy" train.

If it's on the engine itself, then the momentum effect will be present no matter what you have coupled behind. Also I suspect the flywheel mechanism itself would be quieter mounted to the engine, with all the solid metal and a boiler full of water to dampen vibrations. Also the mechanism's performance would be more consistent mounted to the locomotive, since you wouldn't need to be concerned with wet rails or the adhesion of the wagon's wheels.

Clearly one advantage to having a separate wagon is that now with one device you can experience the effect with all of your engines.

I don't think the performance of this little wagon can be expected to be quite as good as the "slomo" device, but it certainly has demonstrated to me that a device like this has the ability to make locomotive operation more realistic, and I think it might alleviate some of the disadvantages of manual control, as Zach demonstrated in his video, where we see his "Millie" happily trundling over bumps and around corners without stalling or speeding away.

Good to hear that it has worked well. I was amazed, as you where, by the difference. Of course the idea has been around for as long as 16mm modeling has but this little German toy has made it an awful lot easier - the axles are the right length and dia and the wheels a straight swap for IP ones. The only down side is the very short wheel base.
With regards product I've often thought this would be the sort of thing HGLW would produce.

I've just posted another video on my thread in the video section. I realized that on my perfectly-flat workbench, it was difficult to see the difference, because even with the regulator just nudged open, the locomotive does not encounter any obstacles. Therefore, other than a slightly faster acceleration, it is possible for it to perform almost as well without the momentum wagon.

Therefore, I built up a "lump" in the middle of the test track, to simulate some uneven terrain or poor track, or what have you.

In the second video, it is easier to see what the momentum device is doing.

I follow this with great interest. I bought a Zecar in September after reading Mr Bonds first post about it, but it just collects dust on the shelf.

Mr. Bond of the DVLR:110370 wrote:The only down side is the very short wheel base.

Why keep the wheel base? The flywheel works on one axle only.

rebelego:110386 wrote:Why keep the wheel base? The flywheel works on one axle only.

That's interesting as that is the only thing that puts me off this idea as the wheelbase is very short.

When I get mine I will see if it's possible.