# Aristo Heavyweights Tracking problems



## Dougald (Jan 2, 2008)

There have been many threads over the years concerning the problems of keeping the Aristo heavyweights on the track, particularly the 3 axle versions. A great many folks seem to have attempted a solution by removing the middle axle or by taking the flange off the middle wheelset. 

Unfortunately, heavyweights almost always rode on 3 axle trucks so these solutions are detrimental to the model's appearance. In addition, the talgo mounted couplers look well ... like crap ... and operate even worse in backing movements. 

Last winter, our friend Greg Adams moved to North Carolina and left the OVGRS the use of his heavyweights. One quick run confirmed that work was needed. The first step was body mounting Kadees which of course only exacerbated the tracking problems of these fairly long passenger cars. 

A quick experiment showed that Aristo's use of a bolster off centre on the truck (to get around sharper curves?) placed all the weight on the axle furthest toward the car end causing the other axles to lift slightly with a propensity to derail. And clearly, 3 axled trucks did not like 4 foot radius curves even if body mounted couplers might somehow snake around. First step was to firmly resolve that these cars should be kept clear of the few 4 foot radius curves on the IPP&W and restrict them to the 5 footers. Next was to remove the bolster and fabricate a new mount for the trucks centred over the middle axle. Fairly stiff springs were used in the truck sideframe to hold the front and rear axles down for better riding over dips or GENTLE undulations in the track. Anything rough will lead to derailments. 

Operation was now much improved but not bulletproof. These cars had an annoying habit of derailing seemingly at random so they were not put in service. Yesterday, as rain washed out our operating session yet again for the umpteenth time this year, Fred Mills, Gord Bellamy and I had a go at making these cars more reliable. The gauge was checked carefully on each wheelsets and precise adjustments made so they were exactly in accordance with the Aristo gauge. Operation improved but still a few random derailments at some switches and at times just on the mainline. 

The Aristo #6 switches were each wideneed ever so slightly at the points by chiseling a bit of the tie spike ... all the flangeways were also checked and the checkgauge at the frogs examined. After tweaking the switches operation again was improved but still not quite bulletproof. 

Lastly Gordie hit on the idea of adding 6 rubber mounts on the underside of each car above the truck sideframe ends to limit the rock in the car as it moved something akin to a sway hanger. Bingo ... problems resolved. 

A 4 car train ran for a long time in the rain without a single derailment going easily through wide radius switches and #6's and traversing 5 foot radius reverse curves. 

It took a lot of tweaking but the cars now look fairly good and operate well. They will inaugarate passenger service in our standard gauge ops just as soon as it stops raining! 

Regards ... Doug


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## toddalin (Jan 4, 2008)

I've been running my heavyweights through 4' radius curves and even back-to-back LGB 1600 turnouts for years without incident. 

I did change the 6-wheel truck on the dining car to a 4-wheel truck (all other SP cars came with 4-wheel trucks). And I do mount Kadees "close coupled" on the talgos (as shown in George Schreyer's web site). Previously I had them on the talgos, but about 1/4" further. This "closer coupling" also helped. 

The worst problem I had was where they would traverse from a 5' radius curve to a 1600 turnout with the straight path then going into another 5' radius curve in the opposite direction (S-curve with a turnout in the center.) As the engine would pass through the turnout, then curve in the opposite direction, the combination of the engine coupler and long talgo on the first heavyweight would push the heavyweight onto the diverging path continually causing a derailment. The brass strip shown below helped to some extent, but was still not 100%. 










Eventually, I redid the section to include a 6" straight section after the turnout but before the 5' radius "S" and this totally fixed the problem. 

I still wouldn't push them through back-to-back 1600 turnouts. That's just asking for trouble. /DesktopModules/NTForums/themes/mls/emoticons/ermm.gif


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