In this edition, we explore one more of our new C-19 release, discuss upcoming appearances, and for our Tech Tip, delve more into speed settings.
In other big news…
Blackstone Models C-19
Included in the newest C-19 lineup is D&RGW No. 342. This interesting loco traveled throughout the narrow gauge in Colorado in her lifetime. Number 342 was operated out of Durango in the early to mid 20s and out of Salida, Colorado in late 20s and early 30s, primarily as a switcher.
B310209-S D&RGW C-19 No. 342 http://www.blackstonemodels.com/new/c19/342.php
B310209W-S D&RGW C-19 No. 342 Weathered http://www.blackstonemodels.com/new/c19/342w.php
Next up is the National Narrow Gauge Convention in Seattle, Washington from September 12th through the 15th. We will be attending and giving clinics and demonstrations throughout the week. If you are in the area, be sure to come by and see us and say “Hi!”
Tech Tip: Speed Tables
Setting up speed tables can be quite an undertaking, but by following a few easy steps, it can be much less of a hassle. Following up from our last post, we’ll use the speed table to limit top speed, and then to speed match locos. First, let’s look at the affected CVs. CVs 67 through 94 correspond to each of the 28 steps in a 28-step table (CV 67 is step 1, CV 68 is step 2… CV 94 is step 28). As we learned in the last post, the decoder calculates the in-between steps when in 128-step mode. CV 66 and 95 are trim CVs that adjust the entire speed table (default of custom) up or down to compensate for mechanical differences in forward or backward respectively.
When setting top speed, first you have to decide how fast is too fast. Many times, you can use a scale speedometer, or a foot per second rule to determine the speed of a loco. Once you determine top speed, to get an even, linear speed table, we’ll do a bit of math -- don’t worry it’s not difficult! Let’s say you desire the top speed of your model to be the same as it when set to ¾ throttle. Each step CV can be set from 0 (0% throttle) to 255 (100% throttle). So for ¾ speed as top speed, CV 94 should be set to 192. But how can we determine the values of CVs 67-93? Simple math. Divide 192 (Value in CV 94 as determined by top speed) by 28 to determine the number by which to increase and decrease each step. This yields 6.8, which rounded off is 7. Set CV 93 to 185, CV 92 to 178, and so on until CV 67 is set to 6. Run the loco, and the top speed, step 128, will produce a ¾ top speed.