Thursday, April 30, 2009

Scale Conversion Chart

Here are the percentages I use when converting between common model railroad scales:

O to S = 75%
O to HO= 55.2%
O to N= 30%

S to O= 133%
S to HO= 73.6%
S to N= 40%

HO to O= 181.3%
HO to S= 136%
HO to N= 54.4%

N to O= 333.3%
N to S= 250%
N to HO= 184%

Thursday, April 16, 2009

Turnout Construction Lessons

Building my first 3 CVTs was a learning experience to say the least. I have a few tips that really made thing fall together more easily once I figured them out.

Use track gauges to hold the rail in alignment as you solder and use the NMRA track gauge to check clearances as you go. 




When bending the diverging stock rail there are 3 locations that are key to a good fit.
1. Kink the rail slightly just before the throw bar to get it going in the diverging direction.
2. After the kink the rail stays straight through the length of the points.
3. Begin the curve of the diverging route just after the point.




When it came time to solder the points to the throw bar I did not want to take a chance of soldering the throw bar to the stock rails as well. To prevent this, I wrap both stock rails with tape in the throw bar area before soldering. (photo only shows one rail taped for clarity)

I align the pints in the main route position, then put a PC tie between the diverging point and stock rail. This will give the right gap for the flange-way. Solder the points to the throw bar.
 
These were the biggest lessons I learned from my experience building the CVTs.

Central Valley Turnout Refinements

After my first attempts building Central Valley Turnouts, as documented earlier in the blog, I was a bit disappointed both in my work and some of the kit components. 

The major problem I was having was with the points of the turnout. I liked the stock pivot and the points supplied in the kit but the method the kit used to attach the points to the throw bar left a bit to be desired. I tried to use a PC tie as the throw bar, soldering the kit points to it, and using the stock pivot in the plastic tie strip. After several attempts I could not seem to get a good solder joint between the points and the PC tie.

I let the project sit for a while until I could come up with a better solution. The solution came two weeks ago when I found Joe Fugate's blog on building CVTs; I had found my answer. I have included a link to his blog in my Model Railroading Links sidebar. (Note: I still build my frogs as I did in my previous posts.)

He uses a combination of  CVT tie strips, PC ties, and Fast tacks filing jigs. I did not invest in the filing jig but can see where it would be handy to have if building many turnouts of the same size.

I have now built the 3 turnouts (#6, #7, #9) needed for the main line of my module set, and could not be happier with the strong and functional results. Now work can begin on getting the main line in place.