Continued Assembly of MIDS and FDS Frame Sections

     The temporary cross brace (white PLA) above had been fabricated previously.  It was used near the joint to maintain proper side frame spacing during glue cure.  It was held in place by friction and a crossed rubber band shown in a previous blog posting.  After glue curing the part was removed.

    The combined MIDS-FDS frame assembly is approximately 8.5" long.  It spans the locomotive driver section from the Front, through the Intermediate and Main drivers.  The three cross braces are built integrally with the side frames along with the four brake hangers visible protruding out from the side frames.  The brake hangers are for the Front and Intermediate drivers.  The correct 67" scale center to center spacing of the driver bearing slots has been verified.  Minor adjustments to the joint were made to put the spacing for the Front driver in correct position and to keep the frame straight and square.

     The rear view shows the residue of the green ABS on the cross frames.  Since they are rather thin, most of the material was left in place and will be painted.  That will result in a corrugated look on the rear of the spacers which is not true to prototype.  The material might be removed with a very small cutter on a Dremel tool, but since the parts will essentially be buried deep inside the locomotive, they will be left as is.  

    Three sets of drivers, bearings and axle are shown alongside the MIDS-FDS frame portion.  From left to right they are the black ABS Main, black ABS Intermediate and green ABS Front (or Back).  The Main and Intermediate will be used on the model while the green Front or Back will be replaced with a black set.

    The frame is placed inverted to permit insertion of the Main driver set by sliding the bearings into their respective slots.

    While still inverted, the Intermediate driver set is slide into position in a similar manner.

     Finally, the Front driver bearings are slide into their respective slots.  At this point the pedestal binders would normally be installed with screws.  They bridge across each slot and retain the bearings within the slots.  They have not yet been built and will be built following build of the black Front driver set.

    With the pedestal binders in place the frame can be handled without the wheels falling out.  The temporary assembly was carefully rolled over while manually holding the wheels in place so the photo could be made.  The drivers have different size counterweights and the main driver has a much larger side rod shaft.  The insides of the main drivers still need to have residue removed to make them ready for painting.