Momentum wagon candidate?

DGE-Railroad

DGE-Railroad

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I have a momentum/inertia wagon on the "todo" list and had been thinking of using the ubiquitous Zecar (which now seems pretty expensive in the UK, incidentally)

I was playing with my 3yo son and some Lego this morning when I stumbled across what I think may be a possible alternative, assuming the final drive connection for the axle can be solved, which may be as simple as using a lego train axleset.

I do have a Zecar sitting in the cupboard and would say they're about equal in terms of flywheel action. The Lego offering may be a little stronger.
20200729_091832.jpg
 
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DGE-Railroad

DGE-Railroad

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My glamorous assistant and I tried a quick test of the unit with standard Lego friction-tyre wheels and no additional weight.

It manages a 26 degree incline on its own. Sadly the Lego wheels are a little on the small side though.

Still, interesting stuff!

Lego unit friction test
 
Fred2179G

Fred2179G

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20 Apr 2017
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OK- looks good. So what is its actual name/part number?
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
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Tamworth, Staffs.
DGE-Railroad

DGE-Railroad

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The part number I have on the blocks I have tried is 54802. They seem to crop up for around £5 or so. Several on eBay at the moment, but I suspect they're equally obtainable through somewhere like Bricklink.

I need to start my SRRL Bowaters Boxcar project and get it put in there to really try it out properly. I think I may look at getting some Slaters wheels or similar, to see how easy it would be to mate a lego shaft to them. The other option would be a steel axle with broached splines into it, which'd probably negate the cost, or to chain drive from the Lego shaft to the truck axle.
 
dunnyrail

dunnyrail

DOGS, Garden Railways, Steam Trains, Jive Dancing,
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Just had a look in bricklink and there appears to be lots of them for sale in quite a few different countries as well.
 
Fred2179G

Fred2179G

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I bought a couple of these lego blocks to play with - one was not working properly (as disclosed) so I took it apart. I could not find the joint so the table saw was used to get started!

It's just a simple wind-up spring, so I can't see how you'd make a momentum wagon out of it.

20200812_145211_lego-pullback.jpg
 
Fred2179G

Fred2179G

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There appear to have been 2-3 different versions of the same 'block'?
Given the video seems to suggest there is a flywheel, maybe I have one of the different versions.
 
Northsider

Northsider

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I had a quick look on Google when this thread started, and it looked like there were two basic types: a pull-back/let go version, and a flywheel/friction motor one. Clearly the latter is the one that would interest us...
 
dunnyrail

dunnyrail

DOGS, Garden Railways, Steam Trains, Jive Dancing,
25 Oct 2009
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St.Neots Cambridgeshire UK
I bought a couple of these lego blocks to play with - one was not working properly (as disclosed) so I took it apart. I could not find the joint so the table saw was used to get started!

It's just a simple wind-up spring, so I can't see how you'd make a momentum wagon out of it.

View attachment 271507
Oops I think you may have trashed that.
 
Fred2179G

Fred2179G

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flywheel/friction motor one. Clearly the latter is the one that would interest us...
Now you tell me. So how do we tell the difference?
Oops I think you may have trashed that.
I only paid $2.25 for both, plus $4 shipping (6GBP?) and I was told the grey one didn't work right. No sweat.

(I just started a new thread with pics of the serious inertia/drag car that I just acquired.)
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
26,524
Tamworth, Staffs.
So how do we tell the difference?
Of the Lego cars:

One is a 'pull-back' (that winds the spring), you let it go and it runs forwards until the energy is spent..

The one we are interested in; You 'scoot' it forwards a number of times, and that spins-up the flywheel inside.. Let it go, and again, it runs until the stored energy is spent..
It adds inertia into the system, taking energy to be spun-up, and then putting that energy back into the system, when slowing down.

How you work-out which is which (part number, perhaps) I do not know.. :(

I suppose you have to ask the Vendor?