Are both O31 and O36 switches compatible with FasTrack O36 oval?

Yes and Yes. All of the Lionel fastrack switches are compatible with your layout. The only difference is the diameter of the circle they make.

So, for your purposes of creating a siding, either one will work - it's just that the O-31 will make a sharper turn/curve than the O-36 and so forth.

The longest siding you could make would generally be a diagonal so, if you're trying to make the longest siding possible in the interior of your oval, you might want to go with an even larger diameter switch so you don't have to use S curves, although they may not be made in a manual switch. On the other hand, if you're trying to squeeze in a short siding between roads and buildings, you may be better off with a smaller diameter.

Try experimenting with SCARM to plot your layout and see how the various switches look.

Thank you. I have created a layout in SCARM using the O36 oval that I have and two O31 switches. Looks like it is a good fit.

You're right - looks great ! You could use a 30" straight piece of Fastrack on each siding instead of three (3) 10" pieces and save a little on cost and eliminate potential continuity issues.

Richie C. posted:

...30" straight piece of Fastrack on each siding instead of three (3) 10" pieces and save a little on cost....

The 30" sections are usually priced more than 3 10" sections on the street - Amazon - 17.59 vs 16.50 for example.

BTW, Fastrack is identified on the underside. 

An exception is this O36 manual track switch:

Are most O gauge that can traverse 036 also able to handle 031 ??

ADCX Rob posted:

Richie C. posted:

...30" straight piece of Fastrack on each siding instead of three (3) 10" pieces and save a little on cost....

The 30" sections are usually priced more than 3 10" sections on the street - Amazon - 17.59 vs 16.50 for example.

You're right …. $13.80 versus $14.95 at my LHS, but worth the extra buck IMHO if it's going to stay in place for awhile.

geysergazer posted:

BTW, Fastrack is identified on the underside.

         

        

What does it say on the bottom of the 30" pieces?

GVDobler posted:

Are most O gauge that can traverse 036 also able to handle 031 ??

No.  There are several locos which require O36 and will not run on O31.  @drabina I wouldn't use O31 switches, you're not going to save that much space.  Keep everything O36 minimum in case you want to get a loco that requires the broader curve.  If you ever get tired of hearing all the noise from Fasttrack, you can upgrade to Atlas O.

Also: many locomotives that MTH claims will run on O31 work much better on O36.  I personally wouldn't build a new layout with O31 today.  My $.02.

Why not use 036 for the sidings. That way if you ever change the layout the 036 will fit right in with making an oval. 

I read this topic and opened  to play with it to see the effect of o-36 vs. o-31 switches.

I noticed that SCRAM has the length of the o-31 as 11.38", but Lionel Catalogs state they are 10". I know that o-36 are actually 10".

I am writing this because this will effect the actual length of the sidings. If they are 10" length, then the sidings can't use 30" pieces unless the oval is expanded.

This may or may not matter to you.

Mark W.

ADCX Rob posted:

geysergazer posted:

BTW, Fastrack is identified on the underside.

         

        

What does it say on the bottom of the 30" pieces?

They are not marked with the length (at least on mine). They simply say "Fastrack" - "Lionel" and "Patent Pending" in different locations.

The OP stated he wanted to use manual switches and, AFAIK, the only manual switches Lionel makes right now are O-31. There are manual O-36 switches on the secondary market or he'd have to find an LHS with some O-36 NOS manual switches, but I agree that O-36 is the way to go.

The oval could be expanded slightly by using a small (4.5") straight section or possibly O-36 quarter curve pieces in the middle of the existing curves to fit the 30" straights, if necessary.