Mini 1948 Trials Southern Style

Having just replaced the magnet in my Wrenn unrebuilt BoB bulleid pacific with a Neo magnet I thought I'd do a haulage trial on my 1 in 28
helix. The Wrenn loco could haul an 8 car train up the helix but could not start it, would keep going with a push start. The unrebuilt modern BoB Hornby loco would just slip its wheels even with a push start would slip to a halt. The rebuilt Hornby BoB could start the train with a little slippage unaided and pull the train up OK.
Conclusions Hornby have managed to imitate life with better haulage of their rebuilt over the unrebuilt. Despite the weight advantage of the Wrenn over Hornby the Hornby rebuilt still has better haulage capacity. So must be down to a better motor and less losses in the transmission. Good to get the Wrenn performing well again though. As an aside I was surprised at the haulage capacity of the Hornby Q1 when I had done trials with that before, disappointed with the M7 though.
Test was conducted with 3 Bachmann bulleid coaches, 3 Hornby mk2a coaches, 1 Lima mk2b and 1 Airfix mk2d. All three locos were running on DCC at @ 18V AC on DVM.
Chris
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It's most likely down to torque, or more accurately torque applied *smoothly* at the right speed - just like the real thing really. Any "snatchiness" starts a slip, and once slipping you've had it.
It's always a good laugh at an off-road trial watching the new kids on the block with their fully tricked-up 300hp motors getting slaughtered by a 1949 56hp 1.6L Series One's until their drivers realise power has very little to do with it, a gentle right foot is always best, but if the vehicle does not have high torque at low revs they ain't going anywhere.
Cheers Richard
--
www.beamends-lrspares.co.uk snipped-for-privacy@beamends-lrspares.co.uk
I have become... comfortably numb
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 16 Jul 2008 08:13:38 +0000, beamendsltd

I once had a ride in a Stanley Steamer. Its starting torque was amazing. But that's steam for you.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Steam cars can be surprisingly fast, and quiet. They were a bunch of them at Camborne, Cornwall on Trevithick Day in April, along with a wide assortment of other steam-powered vehicles including a ex-GWR tank loco (in light steam and sitting on rails, but not mobile).
--
Martin S.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
beamendsltd wrote:

I'll try tweaking the dither settings on the Wrenn decoder to see if it makes a difference.
Chris
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.