Im talking about laying out flextrack, not hand laying track. I think I know how to draw out a curve to the radius you desire using a yardstick. Question, how do you draw out a turn on a shelf layout? The shelf is too narrow to put the pointer on. Its hard for me to properly describe what Im trying to say, I hope you understand what Im trying to say.
There are several ways of doing what you are asking. One is to have a dead end type transom. A stool or something that is the right height for the point of your compass trammel would be one. Another is to make some radius templates on some stiff card board or even some scrap Masonite. Another less accurate way is to use a sting tied to a pencil and held taught at the right radius and swung in an arc.
The template would be your best bet. if done right you can even lay out the easement into and out of the curve on one end. Mark the end of the easement for continuing the curve and flip it over for the easement out of the curve.
Pete
If you have a camera tripod, you could use that to mount one end of the trammel.
Dante
I just cut out cardboard templates of my minimum radius. I wasn’t too fussy about my curves being a set radius just so long as they didn’t go below my requirements. I used a bunch of these to check as I went.
Brent[C):-)]
Invest a few bucks in a metal track alignment gauge from Ribbonrail. I have the 10" version but you can also purchase a 5" version. These little gauges are invaluable. Does away with all of the guess work and all of the homemade devices which leave a lot to be desired.
Rich
To draw the lines I used a scrap of wood and my camera tripod. To keep the alignment I hace the Ribbonrail gauges, although with Atlas flex it’s easy to get a smooth curve without kinks because it is easily flexed yet wants to spring back - like bending a thin stick.
–Randy
An electrician’s conduit fish tape is perfect for something like this, because it will automatically form the transitions at each end of the curve.
Pin one end in place, then push or pull the other end until you get the degree of curvature that will fit in the allocated space. Then simply draw along the curvature of the fish tape.
Depending on the radius you want, a section or two of sectional track can be use as a template. I have used this as a check gauge after locating flex where I suspected I might have formed a kink.
Chuck (Modeling Central Japan in September, 1964 - Atlas flex, hand-laid turnouts)
I just went out and got some poster board. Cut out a few different radius on a few boards and used them as templates as needed. Like “batman” but not as thin. Used push pins to hold them in place while laying out the curves till I got them set like I wanted.
For outside corners, I simply used the largest radius sections of pre-cut roadbed that would fit.
For inside corners, I guess-timated roughly where I wanted the curves to begin/end, then clamped a board to the top of the benchwork at the approximate mid-point, its free end extending out into the aisle. I then used a “yardstick” with holes drilled at 2" centres from 30" to 48" to select the most suitable radius. You can re-position the “free” end of the clamped board as necessary, or re-locate the clamped end to alter the proposed end-points of the curve.
Wayne
Ribbonrail also makes Epsom board roadbed pre-cut to specific curve radii. You could get a four-pack of your intended radius curve and use them as templates to draw the outline of the cork or whatever roadbed you’re planning to use. Or of course, you could just use the Ribbonrail roadbed !!
This is what I’ll be doing for the CR&T as a starting point. So, it will be a combination of moving the tripod, and adjusting the trammel/radius inch-by-inch until the appropriate radius is discovered.
A template method will also be employed, along with some sectional track used as a template. Not everything, due to benchwork location, may be accessible by the tripod/trammel. In fact, the “bent-stick” method along with the flexibility of Flex Track may be the easiest solution. Thus, whatever works is really the modus operandi.
In high school, I was an all afternoon major in Vocational Drafting. You would be surprised to learn how many machinery/part blueprints and architectural perspective plans have a radius center-point that begins many inches off to the side of the drawing itself – The architectural radius can be many (many) feet off of the actual drawing.