Center Finder
When it’s time to stake out some middle ground.
I was trying to find the exact center of the root rib on an Aquila XL so I could replace the tiny 1/4" rods with a decent 1/2" carbon joiner. Trying to get the measurement just right with just a rule, wasn’t that easy. I had a Robart center finder that has really helped me find centerlines for hinges and such. The only problem is that it is too small for a lot of my needs.
Soooo…I made a quick and simple center marking gauge large enough to fit the thicker ribs on many of my planes.
Materials
- (2) 1/4 inch by 3/8 inch by 3 inch block (you can vary the sizes however you want)
- (1) 5/8 inch by 3 inch block (the longer this block the thicker the thing you want to find the center of can be)
- (2) Machine screws ( I used 8–32 stainless because that’s what I have handy)
- (2) Nuts
- (2) ‘O’ rings (optional)
- (1) Scribe insert (optional)
- Cut out the blanks and mark for the holes.
- Drill the appropriate end holes in the three blocks. I counter sunk for the screw heads, but it is not necessary.
- Assemble the unit (I chose to use knurled nuts and “O” rings to make it work like I wanted).
- This is a critical step to get the exact center. Take and push the blocks together and scribe a line on the main block. Flip the outer bocks the other direction and scribe again. This gives you an “X” right in the center of the block.
- Drill the center hole. I chose to use a center scribe insert, since I had several in my tool chest, but you can drill a small hole for a pin or a larger one for a pencil.
Thanks for reading. Please let me know what you think or if you have any questions, feel free to write a response below.
©2021 Tom Broeski
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