The figure shows a magnet mounted to the inside of a wheel. Based on its placement, it looks like it could easily interfere with the guard rails for turnouts. Del?
Todd Brody said:
The figure shows a magnet mounted to the inside of a wheel. Based on its placement, it looks like it could easily interfere with the guard rails for turnouts. Del?
I didn’t see the article, but I know when I did my speed and distance car I just made sure the magnet lined up with the sensor, although I’m not sure how critical even that is. Once you put the magnet in place to clear a guardrail, you can rotate the axle and see if it trips the sensor or not. I don’t think I have had any problems with the guard rails and the magnet interacting.
Let’s see, that would be October issue which came a bit ago, and it happens to be within arm’s reach from here. 
Page 38, ah, there’s photo in question, top page 39.
Ah, yes, I see what you are getting at, magnet is on inside of flange and further from axle than the wheel tread is.
And in fact is at extreme edge of flange, which puts it below railhead height when that side of wheel tread is on rail.
Magnet in article photo looks to be pretty thin, but still, I have questions about it being below railhead height and its potential interference with guardrails, switch frogs, crossing diamond frogs, grade crossing flangeways.
Todd Brody said:
The figure shows a magnet mounted to the inside of a wheel. Based on its placement, it looks like it could easily interfere with the guard rails for turnouts. Del?
Todd - The placement of the magnet was more or less dictated by the wheel. Being a spoked wheel, that was just the best place to put it. As it turns out, the magnet is very thin and clears the guard rails in an LGB turnout. Any thicker and it would not.
Another potential problem with mounting the reed switch in parallel with the axle is side play. As the car rounds a corner, the reed switch can be (and was in this case) too far from the magnet to trigger. This is solved by adding washers as spacers on the axle to limit that side travel.
I would think adding spacers only on that axle would not impact the “compliance” of the that truck at all. Good solution.
Greg
Likewise I have not seen the article. Here’s my odometer/speedo installation I did about 5 years ago on an Aristo’ 20’ gon. Regular cheepo (Lidl, uk/european budget supermarket chain) cycle speedo. Just used a smaller magnet I had lying around to replace the oversize spoke mounting one supplied. Made sure everything oriented the right way and nothing fouls allowing for any axle play. Gives a nice steady reliable reading. Measured the wheel circumference X 1:20.3 (guess what I run most of the time) bingo scale speed and distance readings. Much like installing a chuff trigger on a tender wheel. P.S It also doubles as a track cleaner, fitted wit a set of LGB 50050’s.
I’m spoiled:
Electronics in a hopper:
If you have a model that has a scale 26" wheel, and tell the bike speedo your bike wheel is 26", won’t the readings already be properly to scale for both speed and distance?
makes sense on the face of it.
Russell Shilling said:
If you have a model that has a scale 26" wheel, and tell the bike speedo your bike wheel is 26", won’t the readings already be properly to scale for both speed and distance?
The cheap cycle odometer/speedometer I bought needs to have the wheel circumference programmed into it, not diameter - not all bicycle wheels are 26" and anyway a stated wheel size is usually just the wheel not the total diameter/circumference with the tire added. I just marked the gon’s wheel and rail and rolled it one turn then marked again and measured. Then multiplied up by 20.3 to give the scale full circumference of that particular wheel and inputted - so yes I have scaled it up so it reads as if it were the full sized article. Minimizes chances of any bad assumptions and resulting errors. I remember those old mechanical odometers with the striker on one of the wheels’ spokes, they assumed you had a 26/27" wheel and tire combined to give you an approximate reading. The modern electronic device as far as I can work out uses a reed switch to activate.
It also gives read outs for CO2 emissions (!) and calories your body burned up. If anybody has the conversion CO2 and calorific value rates for the type of coal used on a K-27 on powering up a constant 4% grade with (loaded) 2 reefers, 2 boxcars, 6 stock cars and a long caboose in tow I’d be most grateful. Then I can really have some fun.(http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-laughing.gif)
