This is the sixth in our series of posts where we are sharing drawings for the White Horse CAD Wobbler Engine. This week we will look at the Wobbler Engine main support. The second part of the second sub assembly.
Next week we will look at the main bearing which supports the flywheel and counterbalance shaft.
Lets look at some of the supports features in a little more detail. If you would like to refer to the PDF engineering drawing it can be found by clicking here… P9999-13102_Rev1 you may notice this drawing has 2 sheets…
The main support is the backbone of the engine. It supports the piston block and the main shaft bearings. For the engine to work as intended it is important that the plate is flat and sits perpendicular to the base. We have controlled both of these features using geometric tolerances.
Flatness is important for smooth running. If this part is not flat, the piston will not slide freely in the piston block. The tolerance shown here allow the plate to have a MAXIMUM out of flat error of 0.075mm. This means that the entire front surface of the part must fall within 2 imaginary planes that are 0.075mm apart. If any part of the surface falls outside of these 2 planes the part is outside of specification.
The main support has been designed to be manufactured from ground flat stock, also known as gauge plate. The view on the right shows 2 “machining prohibited” surface finish symbols. If the correct material is used it will not be necessary to machine the front or rear face. We have also added a drawing note reference to the thickness dimension.