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ABS Legs for Modules
In my quest to find a stable leg system for my modules, I looked into the use of ABS rigid plastic pipe that is used in plumbing.  I found the advantages of ABS were many - cost, fabrication, simplicity, standardization, availability of components, easy to cut the pipe to any length, easy to glue the components together, no fancy power tools required.  And, most important, a very sturdy, stable, simple system!

End-Caps
The ABS end cap
The ABS end cap.
The first hurdle to overcome was how to fasten the legs to the module.  This was solved by an ABS component called an "end-cap".  One end is the typical union which glues onto ABS plastic pipe.  The other end is a threaded female connector, with a matching male plug that has a square nut on the end.  These are typically used as an access to clean the plumbing system when it gets plugged up - simply unscrew the male part and do your work.  The leg simply unscrews from the end-cap which is now fastened securely to the module. 


But how to fasten this end cap to the module?  Very simple!  Cut a short piece of 1"x 4" wood about 6" long.  Cut a square hole in the wood the same size as the nut on the end-cap and glue the end-cap into the wood.  Then fasten this assembly with 4 woodscrews to the cross member at the end of the module.  For extra security, put a nut and bolt through the end-cap to the cross member.  The leg simply unscrews from the end-cap which is now fastened securely to the module. If your club wants to change the length of the legs, simply saw the leg in half, glue two unions to each end, and glue a short piece of ABS pipe that will bring your leg to the new height.  First problem solved. 

Leg Levellers
The assembled leveller.
The second problem was to figure how to adjust the length of the legs so that one module of different height could connect to another module.  As I wandered the aisles of my local building supply store, I came across an ABS component that is used to connect dishwashers to the plumbing system.  One end is the typical union which glues onto ABS plastic pipe.  The other end is a threaded hole 3/4" in diameter. I picked up this dishwasher adapter, walked over to the section where the bolts were, found the right size of bolt and screwed it into the threaded end of the dishwasher adapter.  Voila!  Second problem solved!  I quickly purchased the necessary components, loaded them in my car, went home and started sawing and gluing. 

However, when I stood the module up with my newly fabricated plastic ABS plastic pipe legs, the module wobbled like a new born baby deer.  While the wobble was less than with the typical wooden legs I had previously made, I still wasn't happy.  I needed a good bracing system - one that would pass the "cement block" test. 

Fibreglass Bracing System
So back I went to the building supply store and started wandering the aisles in search of a solution.  By mistake, I turned down the aisle where they had the chain link fencing.  There staring me right in the face was the answer.  Chain link fence is fastened and tensioned to the end posts by a very strong but light-weight fibreglass "tension bar".  If I cut and drilled the tension bars, I would have a simple system for stabilizing the legs.  There was just one problem.  How could I fasten the tension bars to the legs?

Hose Clamps To Tie It All Together
 
The modified clamp
This took a lot of thought but each time, I kept returning to the aisle where they sold the flexible plastic pipe.  I just happened to look up and there the solution was staring me right in the face - Hose Clamps.  The kind you use to fasten flexible rubber hoses or the PVC plastic pipe.  I bought the number that I figured I would need, quickly went home, down to the workshop, fired up my drill press and drilled a hole in each of the clamps.  I inserted a bolt and nut into the hole, loosely attached the clamps to the ABS legs, screwed the legs onto the module, attached the tension bars to the bolts on the clamps (and to the module), adjusted and tightened everything up, and put a cement block onto the module.  Eureka!  It worked!  It would take a major tornado to collapse this setup. 

Now, if you're interested, we give you the details below.  If you try it and you like it, let me know.  If you try it and you can improve on it, also let me know.  I might be able to get 3 cement blocks onto the module. 

The Details
The ABS end cap.

The legs for the modules are 1½" ABS rigid plastic pipe.  The pipe is fastened to the underside of the module using a threaded end-cap. Cut a short piece of 1"x 4" wood about 6" long.  Cut a square hole in the wood the same size as the nut on the end-cap and glue the end-cap into the short piece of wood.  Then fasten this assembly with 4 woodscrews to the cross member at the end of the module.  For extra security, put a nut and bolt through the end-cap to the cross member.  (Use a T-nut drilled and epoxied into the top-side of the cross member.) 


Leg Levellers
 
The assembled leveller.
For levelling the leg, a threaded ABS "dishwasher" adapter fits the bill. A 2" long bolt is screwed into the bottom of the dishwasher adapter (this requires a little persuasion the first time you thread the bolt into the adapter but is very sturdy).  This means that you can increase or decrease the height of your legs by about 1" - more than enough room for setting up your modules on the roughest of ground. 


Using some ABS glue and a Q-tip to apply the glue, glue the ABS end-cap onto one end of the ABS pipe, and the leg leveller onto the other end.  If you had your 1½" pipe cut at your building supply store, there's no cleanup required.  If your club changes the height of the legs, it's a simple matter of sawing the leg in half, cutting off or adding some extra pipe, and glueing it all back together with a couple of couplers - ABS couplers, that is. 


Fibreglass Tension Bar Braces
Bracing is fiberglass tension bars  used to hold the ends of chain link fencing.  The bars are 1/8" x 3/8" and come in lengths of 4' and 6'.  I used the 6' size.  Each set of 4 legs will require five 6'-long tension bars. For sway-bracing, cut one tension bar in half producing 2 pieces 30" in length.  For the X-part of the cross bracing cut one tension bar in half (producing another 2 pieces 30" in length).  For the horizontal member of the cross bracing, cut one tension bar about 21" in length (this length will depend on how far apart you position the ABS legs).  Drill 3/16" holes in each end of the tension bars (to take 3/16" diameter threaded screws). 
All Fastened Together With Hose Clamps
To fasten the tension bars to the 4 legs requires 12 hose-clamps - the kind used to connect flexible PVC pipe or rubber hoses together.  The clamps can be easily fastened and adjusted to the ABS legs using a screwdriver or a wrench.  Once in place, the clamps don't have to be removed from the legs.  Accuracy in the length or placement of the tension bars is not critical.



Modifying the Hose Clamps
Now here's the secret.  Drill a hole in each of the clamps, insert a threaded flat-head screw (head on the inside), keep the screw in place with a nut and, voila, you have your fastening system. 
The modified clamp
More specifically, drill a hole that is slightly over 3/16" in each of the clamps.  (This may require cobalt drill bits as the clamps are stainless steel.)  To help with the drilling, fasten the clamps to a short scrap of ABS pipe.  This will serve as a jig to hold the clamps in a vise as you drill. 

You will need 3 different lengths of 3/16" threaded screws - ¾", 1", and 1¼".  The bottom clamp requires a screw 1" long.  The middle and top clamps require screws that are ¾" long.  The module-end of the sway-bracing requires 1¼" screws. 

Insert a 3/16" threaded flat-head screw in the hole you just drilled (flat head is inside the clamp).  Thread a nut onto the screw.  A total of 3 clamps are required for each leg (3 clamps x 4 legs - 12 clamps in total). 

Assembling the Cross Bracing
Slide 3 clamps onto each leg (top and middle clamps have ¾" screws, bottom clamp has 1" screws).  The tightening nut for the top and bottom clamps should be on the outside of the leg.  The tightening nut for the middle clamp should be on the outside end of the leg. 

For the cross-bracing, insert the 21" length of tension bar over the screws on the bottom clamps (make sure the nut to tighten the clamp is on the outside).  Next, insert the ends of two 30" tension bars over the screws on the bottom clamps and fasten with nuts.  Insert the other ends of the 30" tension bars over the screws on the top clamps (again, make sure the nut to tighten the clamp is on the outside) and fasten with nuts. 
Assembling the Sway Bracing

For the sway-bracing, drill a 3/16" hole on each side of the module about 20" in from the end of the module.  Insert a 3/16" threaded screw (about 1¼" long) and fasten in place with a nut.  Insert a 30" tension bar over the screw on the middle clamp and fasten with a nut.  Attach the other end of the tension bar over the screw in the module and fasten with a nut.
The assembled legs.

Tighten It All Up
Adjust the bars and clamps as required and tighten the clamps.  Once the clamps are tightened, you have a most sturdy module.  All swing and sway has been eliminated.  This photo shows what the assembly looks like. 


Disassembly
For disassembly, loosen (but don't remove) the clamps.  Using a plumber's trick, the tension bars can be stored in one (or more) of the legs.  An extra threaded end cap will stop them from wandering.
I hope you've enjoyed this tour.  If you'd like to see a bit of the history of some of the railways in Eastern Ontario, click on the "Home" button.   Or, if you'd like to see how we installed the Atlas 341 DMD decoder into our Atlas GP7s, complete with headlights, click on the "Next" button. 
 
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