What is a car grid ?

[sahir]

Hi...

i wanted to know what is a car grid /grid lines....and how are they different from work lines..? I m newbie to fixture design for automotives...so start from the basics...Thankz..

Have good-day..

 

[GregLocock]

In the old days it was a 4 inch grid, in all 3 dimensions. Full size drawings of the car were layed out on these grids.

The origin was somewhere in front of the car, car centre line, , and somewhere below ground level, in at least one car company.

Nowadays the location of the origin is still anybodies guess, but at least we've settled on x as longitudianl, y as lateral, and z vertical, with a 100 mm grid, although of course the grid as such is much less important now.



Cheers

Greg Locock

 

[sahir]

Thankz Greg...

Also i wanted to how work lines are different from grid lines...And how to show them in the different views with respect to car grid/grid lines.?

Thankz Again...

Chao.. <

 

[carefully]

In the REALLY OLD days, we used a five-inch grid. Went to 100 mm (about 4 inches) with the advent of the metric system. A workline is what the draftsman draws/uses in order to accomplish some kind of special projection - true view, radial section, etc. Nowadays the 2000 mm X gridline is located at some point on the dash panel. I believe the dash was X=0 in the old inches system. I have a Fisher Body background. Other companies may have been different.

I know GM had at least three XYZ coordinate systems. Fisher body was L=X, H=Y, W=Z. That was because we started a design with a blackboard drawing to make sure all the chassis components and people would fit inside the styling. XY for the side view made sense. The motor divisions used XYZ=LWH because a lot of their chassis layout was done in the plan view. Chevrolet used +X pointing towards the left. We settled on the motor division convention so that we could share FE modeling easily. / dave

 

[GregLocock]

Thanks for the details. In this office I work with people who used to 'draw' body panels with scalpels on aluminium sheet! Now they use IDEAS.



Cheers

Greg Locock