Momentum Van Project

Keith S · Post by **Keith S** » Thu Apr 23, 2015 4:07 am

Here is the first test of my "momentum van" made to Zach Bond's (Mr. Bond of the DVLR) design. The construction thread is in "rolling stock". The wagon uses a little toy friction-car as explained in the February issue of Garden Rail. It provides more gradual stops and starts as well as restricting top speed!
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McRuss · Post by **McRuss** » Thu Apr 23, 2015 7:05 am

Hello Keith,

the acceleration and deceleration in the video is superb, but could
you make a short film, showing the difference when the same loco is running without the momentum van?

Markus

Keith S · Post by **Keith S** » Thu Apr 23, 2015 7:48 am

Yes, I suppose I'd better. That would be more useful information.

Dr. Bond of the DVLR · Post by **Dr. Bond of the DVLR** » Thu Apr 23, 2015 5:15 pm

Super stuff - looks like yours works even better than mine - how heavy is it with the drill bit set out of interest?

Keith S · Post by **Keith S** » Thu Apr 23, 2015 7:26 pm

Hi Zach, I don't have a scale at home, but I am planning on raiding the scrap-metal pile at work for some weights and I'll weigh it then.

I realized after posting the last video, that a perfectly-flat work bench isn't the best way to test a device that is meant to improve a train's performance on rough, bendy track. Therefore, I built up a "lump" in the middle of the test-track to simulate a bad piece of track. Here, we see the locomotive without, and then with, the momentum wagon. I placed the same amount of weight on the regular wagon as on the momentum wagon in order to remove that variable. Regulator setting is another variable, therefore each time I tried to open the regulator the same amount, to give the train enough power to climb over the "bump". Here are the results:

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Soar Valley Light · Post by **Soar Valley Light** » Thu Apr 23, 2015 9:00 pm

Keith/Zach,

This looks very interesting - and very effective too. Is it expensive and is much skill required to build it?

All the best,

Andrew

tom_tom_go · Post by **tom_tom_go** » Thu Apr 23, 2015 9:04 pm

Soar Valley Light:110377 wrote:Keith/Zach,

This looks very interesting - and very effective too. Is it expensive and is much skill required to build it?

All the best,

Andrew

Cheap:

http://www.amazon.co.uk/Kikkerland-1589 ... ords=zecar

Keith S · Post by **Keith S** » Thu Apr 23, 2015 9:13 pm

Easy:

All you need to be able to do is cut a rectangular hole in the deck of a wagon, and pull the road wheels off one of these "zecar" toys and replace them with railway wheels. If you order an IP wagon kit for 45mm, you'll get insulated wheels that you can pull off the axles (even if you intend to run on 32mm) The axles on the "zecar" are already the right length for 45mm, but you can slide the wheels in or out to suit either gauge. Use the axle boxes and bushings from the wagon kit, the "zecar" will just hang off the axles in the middle but the wagon's weight will still be on the original bushings.

I would say that making one of these momentum wagons would take perhaps half an hour to an hour longer than assembling the wagon kit itself.

Soar Valley Light · Post by **Soar Valley Light** » Thu Apr 23, 2015 9:15 pm

Thanks Tom,

Looks like a worthwhile investment. At that price it should be possible to have multiple vehicles fitted. Certainly one in a passenger vehicle and one in a freight. I guess fitting them in the brake vehicles would cause the train to behave in as prototypical way as possible. I do wonder if a light train between the friction vehicle and the loco might get pulled over sideways on even averagely tight curves.

Andrew

Keith S · Post by **Keith S** » Thu Apr 23, 2015 9:23 pm

I wondered that myself, I thought it would be interesting to outfit a brake van with one, but then I thought of all the slack between the wagons which might cause a lot of banging about on bumpy track, or like you say, might tend to derail lighter vehicles on corners. With the short trains he runs, Mr. Bond says he can put the wagon anywhere in the train. I can picture a horrible accident however with a moderately long train, and a wagon in the middle derails for some reason, the rear half of the train continuing along and shoving vehicles off the rails in front of it. Imagine if that happened on elevated track! I'd rather have the equipped wagon right behind the loco!

I decided to put mine in a panelled goods wagon, since even on a passenger train, it's not necessarily out of the ordinary to see a covered wagon at the front of the train.

With the £11 "zecar" and the £41 wagon kit, this project only cost £52, not including glue and paint of course.

tom_tom_go · Post by **tom_tom_go** » Thu Apr 23, 2015 9:23 pm

Having the wagon closet to the loco would be best.

McRuss · Post by **McRuss** » Thu Apr 23, 2015 10:40 pm

Hello Keith,

thank you for the second video. It shows the difference clearly.

Markus

Dr. Bond of the DVLR · Post by **Dr. Bond of the DVLR** » Thu Apr 23, 2015 11:13 pm

I've found that even at the back of the train the MV works quite well. That's not very far back on my line but it should allow a little flexibility with stock formation (there's a clip of it at the back of the formation in this video (which you've probably all seen already))
https://www.youtube.com/watch?v=vtIS5EvSaG8

The price on those zecars cirtainly fluctuates, only 4 weeks ago they where £15. Buy them quick while the Euro is down!

Post by **ge_rik** » Fri Apr 24, 2015 6:39 am

Mr. Bond of the DVLR:110384 wrote:I've found that even at the back of the train the MV works quite well. That's not very far back on my line but it should allow a little flexibility with stock formation (there's a clip of it at the back of the formation in this video (which you've probably all seen already))
https://www.youtube.com/watch?v=vtIS5EvSaG8!

What a clever and cost effective idea. I missed your article in GR - nicely described. The beauty is it could also be used on battery and track powered lines.

Rik

Alan P · Post by **Alan P** » Sat Apr 25, 2015 9:20 am

With Zachs assistance i have also built one of these, very useful for controlling skittish locos :-)

There is a page showing how i constructed mine here,

http://www.alspcs.com/MV.html

The page has a link to a video showing the van in use behind my Roundhouse Dylan. The video below shows it being used to tame an MSS Saddle Tank loco.

https://www.youtube.com/watch?v=wp6zAOWWmSc

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