After another long search of the web, I was unable to find a set of plans to make a reasonable sized model Horizontal Directional Drilling machine that was not too complicated. I decided to change that!
To keep the parts a reasonable size and scale, along with a model that would fit on a shelf, I settled for a HDD Machine in 1/10th scale.
Click on the images for a higher resolution photograph.
The model is built from plastic (expanded PVC) which is used in sign making. It has the durability of plastic and the machinability of wood, making it the ideal medium for prototyping.
Parts are cut on a CNC router and complex shapes are made up by layering pieces on top of each other, as seen with the gearbox and undercarriage.
The Tracks are made for motor vehicle timing belts that are freely availble as scrap from service stations.
Non functioning Hydraulic Rams are made from PVC water pipe, available in all hardware stores. The body of the HDD Machine is made from 2mm Plastic Sheet.
The rams are assembled with an 'O' ring to give a more realistic movement and to temporarily hold the position of the rod where placed.
All cylindrical parts are made from PVC pipe or wooden dowel, so no lathe work is required. The articulations are pinned with brass tubing or steel rod.
The parts are sanded down, assembled with CA adhesive and sprayed with automotive aerosol spray paint from cans.
The Gears and wheels are made from 6mm plastic sheet, cut to size and glued together
Once each sub-assembly is complete and painted, they are assembled together and the model starts to take shape. The detailing is the most time consuming part of the build.
The safety fencing is 2.5mm brazing rod, which is easily soldered together with a normal electricians soldering iron.
The service knuckle boom crane is borrowed from another project on this site - see 16th scale Palfinger Crane Plans