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MrIdaho
01-24-2014, 11:56 AM
Here is a jig that is common to woodworkers but has proven invaluable in locating exact center of frame so axle drop outs and front steering axles etc. can be welded in correct relation to frame center. Yes a tape measure is used but it is ATTACHED to the center peg on this jig. Just pushing against peg is not as accurate as actually attaching so tape can be swiveled. Place jig (clamp) on frame as far as possible away from parts being centered for better accuracy. This jig can determine any center of stock from 2.50 to .5 inches but the peg must be centered between the two outer pegs.
http://i992.photobucket.com/albums/af44/MrDEB/centerjig_zps2ae6f29e.jpg (http://s992.photobucket.com/user/MrDEB/media/centerjig_zps2ae6f29e.jpg.html)

Twinkle
01-24-2014, 12:09 PM
OH how simple yet effective

Must put on my make list

regards emma

DannyC
01-24-2014, 04:28 PM
Excellent! :-)

Thanks for sharing.


Dan.

stormbird
01-25-2014, 04:31 AM
Hi all

Something I have been meaning to ask you engineer types but this may be the answer ?

How do I ensure when I am drilling a hole it is in the centre of the tube , especially difficult if the tubing is round ?

I assume if I us the above with a small hole in place of the peg it will allow me to centre punch the exact middle of the tube ?

Is there a reason the left leg is shown longer than the right ?


Yes a tape measure is used but it is ATTACHED to the center peg on this jig

How do you do this ?

MrIdaho
01-25-2014, 10:05 AM
A sketchup boo boo. I whipped out that drawing in 3 minutes with little or no editing. Just be sure the two outside pegs are correct in relation to the center hole or peg. I have one or two made from 3/4" wood as well as a PORTALIGN whiuch is perfect for drilling a hole in tubing. I do woodworking as well.
Not even sure the PORTALIGN is even being made?? It holds your drill and now you have a mini drill press.
Another trick to locate center is = using a ruler align an inch mark on one edge of your material then align another inch mark on the opposite material edge (your ruler is now at an angle in relation to the two edges of the material). Your center is half way between your two inch marks. I used this method for designing irrigation system layouts for head to head sprinkler coverage.