Along with the airbrush set up I picked up Thursday, I also snagged a 1967 copy of an Arnold Rapido track plan book. Seen its better days however! Is there any easy way to convert the track plans to other brands of track, such as Atlas or maybe Kato? Or is Rapido track still available?
Arnold Rapido track production seems to have disappeared since the acquisition by Hornby. I don't see why you shouldn't be able to convert a plan to using other brands of track. Depending upon which types of turnouts were used, some adjustments might be necessary. Can you post a photo or a scan of any plans that interest you?
Get a (free) copy of XTrkCAD layout software. They have an Arnold track library. I see it as an option to load but have never tried it. You may be able to put the layout from the book into the computer and then see what equivalent Atlas, Peco, Kato, etc. tracks that may match the Arnold. Good way to do a "What If" simulation on the computer without the actual Arnold tracks.
I;ve never seen the Arnold plans, but is there a grid on the plan? You could transfer the grid to 1:1 on your plywood or foam and go from there. Or, just get some other track pieces and come close by eye. Nothing magic in Arnold's dimensions.
The only dimensional difference I have found with European track has been in the turnouts and a wider selection of them. There you tend to find the sharper turnouts that are not available in US brands and curved turnouts.
Book is in pretty sad shape! IF I can, I'm gonna TRY to salvage what I can, by attempting to scan things to computer.Have a page scanner, so i can scan extra long pages, with no problem! And hopefully, be able to print them out decently! May talk with Mom, about carefully ironing out the pages, to get them as flat as possible, before scanning.
Careful with an iron/heat. May accelerate the deterioration. I would just put some having objects on it like books, etc. and wait a week.