Tuesday, January 22, 2013

Make A Jig

A "Jig" is a type of custom-made tool used to control the location and/or motion of another tool or item.  A jig's primary purpose is to provide repeatability, accuracy, and interchangeability in the manufacturing of products.
In modeling we often spend much time trying to achieve consistency when we build multiples of items . This can be done by using a Jig which is made to suit the application, in our case, it may be bending wire for handrails or assembling bogies or to assist with difficult fitting of parts, a jig will often provide the answer to a multitude of problems.
Most modelers have at some time found a need to make a jig to achieve a result with their projects and so there must be a whole heap of ideas amongst our group which can be shared to hopefully assist newcomers and even old hands.
I would like to encourage  all contributors on our Blog to share their "Jig" ideas under this theme of
"Make a Jig"  
To kick off, here is a simple little Jig I use for applying the End Bargeboard to Double Skinned Roof carriages.

This little jig is made simply from some styrene strip of .75mm thickness. It is designed to work as a spacer which is placed on the end of the coach to assist with  gluing the bargeboard into place, leaving a gap as per the real carriage. 
To explain the situation  - In picture A below, the brown carriage is modeled to represent a Double Skinned Roof version with the large End Bargeboard. The Green carriage is modeled to represent the carriage after the double skinned roof has been removed. Picture B shows the side view and it can be seen that the double skinned roof (circled) on the AZ carriage extends a bit beyond the end of the carriage to allow for air to flow under the protecting bargeboard and between the roof space. The carriage on the right is the modified single skin roof version and it can be seen that the roof is somewhat shortened. 

To make the Bargeboard Jig - Take a straight section of .75mm Evergreen strip styrene and cut it to fit between the roof and side walls of the carriage, then add extensions to reach upwards to the curve of the roof. Glue it all together on a sheet of glass or flat board to achieve a flat Jig.
The Bargeboard Jig is put/rested in place on the end of the assembled carriage body after the roof has been fitted. I then apply small drops of glue to the under side of the roof "between" the extensions, taking care not to glue the jig to the carriage body.
 Then slide the curved end bargeboard on top of the jig and press it up under the roof. Once the "tack" spots of glue have dried, remove the jig by carefully sliding it out, then a bead of glue can be applied to the bargeboard and the roof trimmed to match. 
The end result should look something like this!

 Store your Jig so that it may be used again on a similar project.

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