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View Full Version here: : Centre Spotting Tool

Sausageman
23-09-2005, 04:00 PM
I have been reading about all the different techniques used to centre spot your mirrors.
Perhaps those of you with the skills can make a better one.
Here is my design for your evaluation.
I haven't tried this yet, I will wait on your comments.

Mike
square_peg114GT
23-09-2005, 04:14 PM
I suppose it would work. I just question the need for such a tool. Also keep in mind that not all mirrors of the same size are really the same size. I've seen them vary by an 1/8". Your callibrated line needs to determine the true diameter of the mirror.
Sausageman
23-09-2005, 04:17 PM
Ahh well, that would be up to the individual to measure the exact diameter of thier own mirror wouldn't it?

Mike
janoskiss
23-09-2005, 05:06 PM
Seems unnecessarily complicated to me. And there is that word "exact" appearing more than once in the diagram, which is a bit worrying. A compass with a felt tip pen and a small wooden block that hugs the mirror is all you need; like I posted on the Centre Spotting Discussions (http://www.iceinspace.com.au/forum/showthread.php?p=46807#post46807) thread.

The point of using a compass is that nothing needs to be exact. You keep the compass opening at just approximately half the mirror diameter, and then draw three arcs at approx 120 degrees apart, and this will show very accurately where the centre is. And for extra precision, you simply repeat the steps with the compass opening readjusted so the pen tip strikes closer to centre. Then you can place the sticky-backed spot carefully with tweezers. (The drawings may be a bit misleading, with the spot fitting so neatly inside the triangle. No need to be precise. But you do need a reasonably good compass without any backlash.)
RAJAH235
23-09-2005, 08:42 PM
Why so complicated? A cardstock or paper disc is all you require. Takes 5 mins to do. :shrug: :D L.
ps.KISS.
janoskiss
24-09-2005, 12:30 AM
L, Who are you calling stupid? :mad2:
:nerd:
RapidEye
24-09-2005, 01:11 AM
Yup - seems like an aweful lot of effort to go through for something so simple to do.

Sort of like buying an airline ticket in order to get free peanuts :doh:
Roger Davis
24-09-2005, 07:44 AM
Yep, KISS is the best, after all unless you have to do 100's of them you only have to centre dot your mirror once in every 15 years or so!
Sausageman
26-09-2005, 05:38 PM
OK, I get the message :poke:
I'll forget the World wide patent and making my fortune then. :doh:

See I told you I wouldn't make one until you peepul had your say, saved myself hours of work. :rofl:

Mike.