Page 1 of 1

Datum Points

Posted: Thu Aug 12, 2004 9:48 pm
by 912126
Hi

I have a question regarding datum points, and the only topic mentioning them was in the Picture Gallery; hence a new topic.

I have the FSM (for a '90 Legacy wagon), and it has drawings of and distances between the "Datum Points" (Master Repair Locators, Guide Holes, Locators, and Indents).

But I can't find them on my car. I expected some indicator. Little numbers would be nice.

Am I to assume that, for example, Datum Point 2 is the hole where the hood bumper mounts?

Number 9 is on the strut tower, but I don't see any hole or indent.

Thanks for your guidance.

Dale

Posted: Fri Aug 13, 2004 4:01 am
by THAWA
what is a datum point?

Posted: Fri Aug 13, 2004 4:56 am
by LaureltheQueen
i was thinking the same thing

Posted: Fri Aug 13, 2004 5:17 am
by Yukonart
Sounds like reference points used by body shops to realign body parts to OEM tolerances.

Posted: Fri Aug 13, 2004 5:26 am
by vrg3
THAWA and Laurel - Datum points are points on the body of the car that you use to do collision repairs and such. The service manual defines distances between datum points, so you can measure and see just how bent the car is.

Dale - My 92 FSM says, "All dimensions refer to the distance between the centers of holes when measured in a straight line," which would seem to imply that all the datum points themselves are holes. Perhaps they're holes that normally have bolts threaded into them?

On the 92, point 2 does appear to be the hole for the hood bumper. And point 9 appears to be the frontmost of the three holes that the strut top mount attaches through.

Datum Points

Posted: Sat Aug 14, 2004 5:16 am
by 912126
vrg3 - I posted via "Quick Reply" earlier but apparently it was too quick for me.

I will now try to "Post a Reply" .

Despite the FSM's statement that datum points are "Master Repair Locators, Guide Holes, Locators, and Indents", it looks like mostly they are holes for something else, as you said.

Thanks for your input.