Tuesday 18 December 2012

Sleepers

The model is of a secondary main so the installation of tie plates and the prospect of having to install a thousand was something that keeps one awake at night. The key to salvation was the flexible track bases produced by the Aust 7 Modellers and pioneered by Trevor Hodges. These consist of a laser cut ply base that the timber sleeper sleepers are affixed to allowing O scale flex track to be produced by spiking down the rail.

Sleeper Base Jigs.

After much thought it was decided to develop a jig system to allow the production of sleeper base ready for track using the tie plate as the assembly key.

The jig consists of 3 separate pieces. The lower jig holds the laser cut tie base in its correct shape while the second jig or comb allows the Kappler ties to be fitted accurately so that the third jig can position the Right-O-Way tie plates onto the top side of the sleepers. The jig assembles the sleeper base with tie plates in 450 mm lengths of flexible track base ready for installation of rail using the tie plate to gauge the rail.

Sleeper Base Assembly.

Install two of the laser cut tie strips into the two halves of the lower jig assembly and then position the two halves of the second jig [comb] onto the first jig using the 1/8'' [3.2 mm] locator's pins. Fix the ties to the exposed side of the laser cut sleeper base, remove and allow adhesive to dry. The ties you use are 4'' x 9'' x 8'-6'' plain ties available from Right-O-Way or Gywder Valley Models

The adhesive used is the acrylic sealant applied with a scrap piece of styrene. Once complete remove from the base jig using a dental pick. Use extreme care as the glue will not have dried at this point - place aside and allow to dry.








One dry reinsert the assembly into the first jig and using a flat block with 180 Garnet paper sand smooth. Guide this operation by scribing a line's with a HB pencil line down the both sides and  sand until all ties have been touched by the sanding block and 90% is fully removed. 




Detailing is achieved in a time honoured manner by using a 52 or 42 tpi Zona razor saw, X-Acto No 17 blade and dental pick. These detailing methods are covered in great detail in the OST Publications on track mentioned in a previous blog.

Once this operation is complete stain the ties using the "Classic Grey" MinWax stain. This procedure is outlined in full detail on the The Route of The Arrow  article so it will not be covered here.

For more details on sleeper preparation and weathering see the article on sleeper weathering.





Re-install the tie assembly into the base jig and then reinstall the middle jig [comb] ensuring the comb is hard against the tie ends and finally install the top tie plate jig. Clip off 3 pre-painted sprues of Right-O-Way tie plates and begin installation. The tie plates are picked up with a sharp needle - apply a drop off ACC to the base on its centre and install through the opening in the tie plate jig ensuring that the short end [the side with the holes not slots] faces to the outside. Remove the completed assembly from all the jigs and it provides 450 mm [18''] of flexible track base with tie plates ready to install on the layout and ready to accept rail,

Failure to do this will effect gauge of installed track.....!


 

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