Hi guys! Is someone here can help me? I don't remember how to calculate the number of a turnout... I know the number tells a relation between something and something... That's all! Yvan-Martin http//www.trainweb.com/montreal/g-scale
Ivan - welcome to trainboard! To answer your question, the turnout number is the ratio that expresses the angle of the turnout. It's the number of units (inches, cm - it does not mater) that it takes the routes to diverge one unit. The larger the number (6, 8, 10,) the more gradual the angle. It's hard to describe without a picture. Does anyone know of a good diagram on line to illustrate? BTW - the small turnouts that come with model train sets are usually much sharper than number 4 - they have a diverging route that matches an 18" radius (in HO) curve to allow them to interchange with the very sharp curves that come with the set.
Sorry it has taken so long for you to get a reply to your question. The number of a turnout relates to the angle formed by the frog. If you extend straight lines from each side of the point of the frog, at some point the lines are one foot apart measured perpendicular to one of the lines. The turnout number is the number of feet between the point of the frog and that one foot mark. I used the unit "foot" but the measure is independant of unit size. Meters, ax handles, or whatever will work as it is a proportion rather than an absolute measure. The larger the number of the frog, the smaller the angle in degrees. A number 24 frog forms a right triangle with one side of one unit and one side of 24 units. Chuckles
Perhaps easier expressed as 1 inch to the side for every 4 inches forward is a number 4 turnout. 1 inch to the side for every 6 inches forward is a number 6 turnout. 8 inches straight and 1 inch to the diverging route is a number 8 turnout and I wish I had the room to use number 8s. As said above, it is the angle expressed in terms of distance rather than degrees.
Hi Yvan, I guess that your question is in relation with the trackwork on your superb 1.29 garden layout (has the snow melted in the "belle province" ?) I know a British brand called "Tenmile" which makes beautifull turnouts.They are closer from prototype than any G-track stuff I know. In comparison, Aristo or LGB turnouts look like toys... Their prices, at least in Europe, are quite reasonable and the track is compatible with other brands.I thinks they also offer a kit version.If you are interested, I suppose you can find their stuff somewhere on the web. I know a French dealer who carry that brand, but I suppose you can find them nearer to your place... Your SD 40-2 deserve better turnouts Makes me feel strange to write to you in English, but after all, Train-board is born in the USA, isn't it ? A bientot, Marc