What is the difference between a #4, #6 or a snap track turnouts. I have been doing some seaching and I have found this that say #4 turnout, and I’m not sure what they mean. Can someone please help me?
it refers to the distance and the angle of the curved section of the track in relation to the length of the turnout…so in other words a #4 turnout has a sharper angle in the curved section of the turnout then a #6 turnout…(there is a math formula for calculating it but i’m no Einstein and somebody else is going to have to explain that part to you) I use a lot of #6 turnouts but you have to keep in mind that they take a lot more space to install them…I use #4’s in yard areas or small spaces and #6’s on mainlines so that the diversion is not so sharp of a radius for higher speed trains, which lessens the chance of derailment…a snap turnout is basically the same as the mark 3 except that they have plastic frogs instead of metal frogs…they are an "all power “type of turnout (insulated frog)…the mark 3 is an 'all power” turnout except that it can be wired for select control with using the metal frog instead of the plastic one on the snap type …if you are starting out in the hobby, the “all powered turnouts” such as the snap or mark 3 will be good because they don’t require special wiring like a select control turnout needs…the snap turnouts also have the turnout mechanical throws mounted on the side of the turnout which replaces the under -the -table type mechanical switch throw needed for the mark 3’s… if I were you i would purchase the mark 3 type and use the atlas under -the -table switch machine, or a tortoise under the table machine or any other brand as long as it’s an under the table type…it looks more prototype than that big black turnout throw located above the table and on the side of the snap turnout…Chuck [:D]
Another difference is that the Atlas Snap Switches have an 18" radius on the turnout side, so it’s easier to use at the beginning of a curve. Of course, that means the turnout IS curved, rather than running at a tangent off the main track like a regular turnout. So if a plan calls for a snap switch, you can’t substitute a #4, or vice-versa.
FYI…i made a big mistake when i built my layout, i used #4’s on my mainline and because of that i have a heck of a time running a 6 axle locomotive through the #4’s without derailing.
Ok so basically, it all depends on wheather I want the turn out to curve or run tanget. And use the right turn out for the right job. Thanks eveybody for the quick rreplies.
The difficult math formula is that the rail at the frog separates 1 unit in N units of length, where N is the turnout #.
This only applies to where the rail goes straight through the frog.
I would say it basically comes down to how sharp you want the “curve” of the diverging track part of the turnout to be. The higher the frog number, the less the “sharpness” of the “curved” part is, in a short-n-sweet manner of speaking, that is. [:)]
Hope this helps…
Keepin mind that if you use #4 or “snap” turnouts that you will be limiting yourself to 4 axel diesels, steam switchers, and 50’ or less cars. If you want to reliably run longer equipment you will NEED #6 and #8 turnouts.
I used all #6 Atlas turnouts and I have occassional problems with an SD24 with 6 axle. In fact if I did it over I would use Atlas Customline Turnouts since they have a larger curve on the layout . I intend to change a couple of my #6 snaps.
You may be interested in that Atlas sells track templates of various track items for $4.10US. The customline are longer but still my choice for minimum problems.
Ken Ison