Based on discussions the first round of tests, there was significant interest in examining features to improve the maximum train length at grade. This discussion pertains to assessing the impact of clean, adjust & tune process, here after referred to as CAT.
Definition of CAT
I have examined this process before. Previously it was summarized here:
Specifically, CAT is as follows:
1- Clean electrical contacts, clean out old lubricant from gears & bearings & clean wheels
2- adjust motor position to insure it is properly aligned, adjust drive shaft elements to seat properly with no binding, adjust, eliminate any flash from gears or gear box and adjust wheel gage. These are generally as required.
3- tune, lightly lubricate motor bearings, truck gears & tower bearings.
The experience from the above link showed the most benefit from the motor bearings & the wheel cleaning. For this exercise, all three steps were applied. The condition of the old lubricant was good, but was cleaned anyway.
List of engines
For this testing two new engines were added the the data base. Then five engines from the sample were chosen to be carried into this activity. All of these engines are diesels. Additional steam engine activity is planned for a later series. Of the five engines, two are new releases with limited previous running. Two are well used. And one has seen limited use, but was designed more than ten years ago.
The engines are as follows:
1- ScaleTrains “Operator” BNSF SD40-2 in factory new condition
2- Atlas Kato NP RS-11 in well used condition
3- Rapido RS-18, basically factory new subject to my tests over the last five months
4- Atlas China SP&S RS-3 old release with limited use
5- P2K NP SW1200 in well used condition
Why five? While not statistically significant, the average of five will indicate if there is a benefit for doing the CAT activity. The engines were selected with randomness relative to the activity so the results should not be biased.
Standard DC test impact
Show before & after results
Velocity vs voltage
Current vs voltage
Draw bar force vs weight
Performance characteristics vs weight
12 volt velocity vs weight
Summary
G&TL tests impact
Maximum cars vs grade
Weight ratio vs grade
Increase in cars vs grade
Percent change in train length vs grade:
Power vs grade
Show cars vs weight
Summary
1- These results indicate that the CAT benefits are largest at low grades. At the highest two grades the car number increase is small, but the percent increase is modest because the train lengths are low to begin with.
2- the engine that showed the least impacts is the well used P2K NP SW1200. This engine may have been previously worked. It’s draw bar force was good for its weight before the CAT was applied.
3- the two engines that showed the most benefit are the RS-12, well used, and the RS-18, new in the last 5 months.
4- current impact Shows a significant impact on several of the engines. The RS-18 current increases. Interesting. because it has a significant increase in train length.
Conclusions
1- CAT matters. All further testing will be done after CAT is applied.
2- Applies to new & old engines
3- Largest impact is below 4% grade
Next steps
At the same time as the CAT testing, these five engine were run with increased weight increments. These results will be posted in the next few days.
On several of my engine only motor testes in the same test bead engine, the measured draw bar force increased like was seen on the RS-11 & RS-18. It is interesting enough to repeat those tests. The focus will include some pre measurements of motor RPM and Torque calculations on several motors in the same Athearn BB test bed engines. Likely will run two or three to make it a sample of more than one.
Thanks for reading. Come back often.
