This module is based on a 33" square with the fascia outside of this dimension. The original used 1/4" plywood for the fascia and the deck, making for a very light, yet sturdy, construction. You might want to vary your size slightly to fit your own purposes.
Both tracks on this module are O-42 (21" radius), one of which ends at the edges of the module and the other requiring some straight track, either going to the edge of the module, or all the way to the connection 5" inside your neighbor's module (which means fewer track sections and better electrical transmission).
If you're using this corner with 24" wide modules, cut off the dotted
rule and you'll have a module 30"x47" on the diagonal -- the longest dimension.
If using 30" wide modules, just nip off the upper right-hand corner and
your dimensions will be 35"x47".
An O-72 Corner
If you like wider curves and have the space to carry and use them, you'll want to try some O-72 corners. Construction can follow those detailed in Section 1: Construction of this manual, or can be of your own design. We suggest that you keep it simple, and by all means, keep it light.
The illustration at the right should give you all the information you need for these corners. The inside track ends at the edges of the module, so remember to supply two connecting 5" tracks to bridge to the next module. The outside track ends 5" from the edges of the module, so your standard 10" track pieces will bridge the gap.
Howard Packer doesn't like regular Lionel O-31 curves because they're too sharp for good operating and appearance. The wider the better for him. He does, however, understand the need for portability as much as the next fellow, so he devised the corner module diagramed and discussed in this section. He has used an O-72 curve for the front (outside) mainline and combined O-42 and O-72 curves for a second mainline in a module only 39" square.
Now before you say that this doesn't fit our 48" measurement (or multiples thereof), we'll agree, but a corner module doesn't necessarily have to be confined to the 48" measurement. Whwere you will have trouble is when several people bring corner modules and they're not all the same dimensions. You need matched pairs diagonally from each other. For example, if you used two of Howard's and two of the smaller corners diagonally across from each other, you still achieve a working rectangle.
Another place where this odd dimension will cause trouble is in making
an S-shape within a basic rectangle, or if you have two T-modules and want
to connect the two sides of a rectangle through the middle with a series
of modules. If you're using two return loops for an irregular point-to-point
layout, no problem.
Varying Construction
We think the accompanying illustration is self-explanatory, but will add that Howard has used the alternate construction method with side members of 1"x4" material around the perimeter of the module; and in his case he ripped his own boards so the actual dimensions are 3/4"x4"; but we prefer the narrower 3 1/2" ( or 3"), which is just as strong, but a tad lighter. He used 1/2" plywood for the deck so he needed no additional joists. This is very strong, but it's also a little heavy. We've found that experience has taught us a very strong lesson that lighter is better!
Howard can give you his philosophy and construction methods in his own words.
Packer's Compact Corner
By Howard Packer
The reason I designed this particular corner module was to allow for the wide radius curces on the smallest possible table surface. Also, that the module would mate neatly with adjacent two-foot wide modules, and still have at least 3" (the standard is 3 1/2" -- plan accordingly) from the edge of the plywood to the first center rail.
I took a little license with track radius because Lionel uses the outside rail to determine diameter. I used the centr rail because it's always in the center and is a very logical way of determining the diameter of such a circle. (Editor's note: most track plans are geared around the track centerline in determining a curve's radius.)
Because of the variable tolerance in quality controls where the track is made, some of the measurements have to be fudged and some of the track bent ever so slightly.
From one 4'x8' sheet of plywood I was able to make two corner modules and had enough material left over for a T-module top.
My Procedure
These legs cannot be at the interfaces. We've tried that and it makes for unsteady modules. Fasten your legs (module legs, of course) to the frames or strong fascias so they will extend perpendicular between the two edges.
All legs, of course, must meet the same height adjustment requirements of standard modules -- i.e., plus or minus 1" by means of bolts and T-nuts in their bottom ends.
by Matt Jackson
Some of the modern Hi-Rail equipment barely makes it around even the O-72 curves. And those 72' and 80' passenger cars have quite a bit of overhang. Fortunately, with more manufacturers entering the three-rail sectional track market, a wider-radius corner using sectional track has become viable. The track used in this module is the new GarGraves sectional track -- specifically O-72 for the inside mainline and O-88 (with a small fitter section in the middle) for the outside. If you are familiar with the construction techniques involved with Howard Packer's corners and the full O-72 corner mentioned above, this wide-radius version should be easy.
Basically, you start with a the same platform as the full O-72 corner which is a 4'x4' half-sheet of plywood with two diagonal cuts, each 24" off opposite corners. Next, you lay the O-72 Gargraves on the inside main which will be 12" in from the edge; the O-89 curves will be exactly 8 1/2" from the inside mainline and will be 3 1/2" from the module edge -- perfect. Leg and fascia construction are identical to those in Howard's corners, but will obviously be enlarged to handle the larger module deck size. Construction costs will be similar to the compact corner, but the track cost will be higher -- approximately $160 for two loops of track ($40 per module).
You should also be aware of a couple of other items.
First, the module will occupy more space and might not fit in some small vehicles. Of course, with the added size (48" square as opposed to a 39" square), comes additional weight.
Second, some considerations have to be taken for adapting to conventional Lionel/K-Line O-Gauge track (GarGraves on standard cork roadbed is approximately the same height as Lionel O-Gauge). Using GarGraves bridge tracks with adapter track pins would probably make the transition into the corner module smoother.
If you like a wider curve for larger equipment, plus the benefit of being able to run your equipment on either mainline, this might be a good alternative. Remember, however, that you need to bring enough bridge tracks (4 per module), and if you plan to mix these corners with the conventional compact corners, you need to bring two corners with you.
RETURN LOOP MODULES
A Compact Loop
We discovered the return loop module to be one of the handiest of all special modules. Two return loops permit a continuous run of any length, depending on the number of straight sections added in between. Four corner modules are not needed in this case.
Flexibility Adds to Uses
A return loop using 42" diameter track would require a module four feet wide by almost six feet long, awkward to handle and needing a large van or station wagon to transport. They have many advantages, however, and we'll show you plans for one later on in this Manual.
We've also had to bring the curve entering the loop (on the left of the diagram) right to the edge of the module. The proper 5" clearance has been met on the straight section. But the fudging works, and we've enjoyed many hours of operation without derailments, using many sizes of cars and locomotives.
The pieces of track used are probably self-explanatory in the diagram. The short sections ("B") are cut from O-31 curved track and those marked "D" are cut from straight track. Once you're into modules, you'll accumulate short pieces that might be used.
Wiring Tips
Solution: If you're using two throttles, one for each track, we suggest that the track pins connecting the rails at point "x" in the diagram, be insulating pins to keep the two main lines on separate throttles.
If you want to operate both tracks as one, merely connect both the white and red wires to the same terminal, or in the alternative, add a jumper between the two with a switch so you can have the best of both worlds.
The basic wiring is described in Section 3 of the Manual, so there is no need to go into it extensively here. However, since this return loop is used at the end of a modular setup, without being attached to another module at its loop end, you won't need a four-pin socket at the loop end. But wait a minute! We've found that sometimes a loop module is close to another module in an imaginative serpentine arrangement and it can be helpful to connect the two electrically so the bus wires can provide a better circuit. Always plan for the unknown and unexpected.
As shown in the illustrations above and below, a smal yard can be formed with an elongated O-31 return loop. The siding shown branching from the mainline in the set on the left could be created using an O-72 turnout, or one of the new Lionel O-31 turnouts with the detachable half-curve section. The one on the right also provides reversing capabilities, plus a run-around track for the locomotives.
Packer O-42 Return Loop
by Howard Packer
Both the compact and extended compact loops have some problems with some equipment. Trains made up of cars with pre-MPC trucks sometimes fall over to the inside as they go around the loop, especially if they are stopped on the curve and then re-started. If the operator's attention is diverted and a train moves too fast through the loop, the engine and heavy cars may find their way to the floor.
Compromising With O-42 Track
After operating some time with these small circles, I devised a way to make a larger diameter return loop. Of course, O-72 was out of the question -- a 6 1/2-foot wide module is a bit too much to handle easily. On the other hand, O-42 curves represent a good compromise, making a 48" wide module when you add three inches from the center rails on both sides. Conveniently, this also happens to be the width of a standard sheet of plywood.
As the drawing shows, a return loop using O-42 curves can be assembled on a 4x6-foot sheet of plywood. Two people can handle this module (have your medical insurance paid up), but it will require a good size van or station wagon to move it to your meet.
A better way is to make the return loop in two sections so it will be more manageable. Place six sections of the curves that make the first 180 degrees of turn on a separate 2x4-foot module and the balance of the track on a 4x4-foot module. This configuratino can be loaded and brought to the meet by one person (keep your insurance, though), but two people will be necessary to set it on its legs.
The 2x4-foot section needs only two legs at the end. The facing that joins the large section needs only to be firmly clamped to its partner. The 4x4-foot section needs the usual four legs.
It is suggested that controllers for the turnouts and accessories be in a separate box at the end of a pigtail long enough to allow them to be operated from any position around the complex of modules, especially if they are used in an extended loop situation. Otherwise they could be mounted on the 4x4-foot section.
An insulated track pin will keep the white and red power separate and allow for preset controls. Enter the curve slowly, then increase power as more cars arrive on the curve.
A module that lends itself to many flexible track plans is the T-module.
For example, if you want a staging yard, a yard for extensive switching activity, or an engine service area, the T-module placed somewhere in the layout will lead to it. This can lead into or out of a rectangle, or if you're using two return loops, in a "water-wings" arrangement. It can be made to lead off to either side.
By placing a return loop at the end of whatever tracks the T-module leads to, you can set up an alternate route for your trains. Your imagination can conjure other uses.
Construction
We'll leave the construction up to you. You can choose our lightweight
plywood method, the heavier construction, or some design of your own. And
you can use bolt-on, folding, or tubular legs. But whatever construction,
these plans require a module at least 30" wide by four feet long, one of
our standard sizes.
Crescent Model Railroaders
One club that has taken the Tracker module standard further is Crescent Model Railroaders. They have added a third mainline down between the main and secondary, and have substituted Gargraves track for standard tubular. They have also adopted a larger corner module design. More information can be found at the club's website which is linked above and on the Angels Gate Hi-Railers web page.


Track
The original standards call for Lionel Standard O-compatible track (Lionel or K-Line). However, with the advent of the new Atlas-O solid rail track, MTH Real Trax, and MTH ScaleTrax, the tubular requiment has probably long passed. You should build to the standards chosen by your particular operating group and should have plenty of adapter pieces should you link up with other grops.
By changing dimensions slightly, you can use O-42 turnouts, such as those made by K-Line (Editor's note: Watch for inside clearance problems when using longer equipment through K-Line turnouts.). If you want to go the O-72 route, you'll need to follow different dimensions and a different design, such as was done by Woody Gillis in his T-modules.
The dimensions shown are approximate, so you may have to improvise a little here and there. For Howard's plan you'll need two full sections of O-42 curve, plus part of another one, and the track will end at the edge of the 30" width.
The front track ends the specified 5" from each end of the module. You provide one 5" and one 10" bridge track to connect to the module at one end of yours; the person at the other end should have similar bridge tracks to connect with your module.
The second track leaves an odd dimension between the turnout and the module edge. Bridge this with a section that length, ending your track at the module edge, plus a separate 5" piece to complete the connection to the track on the next module. The preferred method is to combine both of thes lengths in one piece of track, which would eliminate the shorter section, reserving the short section to match up with "non-bridge" modules..