# Laser center finder



## Johnwa (Jun 20, 2021)

I came across this recently  and thought it was a good idea.  https://www.centerquic.com
The price tag of $168 floored me though so I made one,




Here‘s a picture with the spindle turning.  The naked eye sees it as a complete circle.





The best repeatability I could get was about 0.01” for a center punch mark.  I was consistently within 0.003” when centering between two lines about 1” apart.


----------



## RobinHood (Jun 20, 2021)

Always wondered about the accuracy, now I know. What do you think is the limiting factor? Beam width?


----------



## Johnwa (Jun 20, 2021)

I think the width does have an effect.  The laser I have isn’t focusable  so I couldn’t change that.  I think that was why it was a bit more accurate when centering between two lines as it was easier to tell when the beam just touched the line.  A magnifying glass might have improved it a bit.  It’s also a matter of where you’re looking from.  I had the best results when lined up parallel to an axis.  Also my laser didn’t intersect the axis of the spindle so the smallest circle i could get was about ½” D.  A smaller circle might have improved the center punch test.


----------



## YYCHM (Jun 20, 2021)

I fail to see the principle of this?

I have a laser pointer on my drill press.  Horrible thing, I gave up on it.


----------



## Johnwa (Jun 21, 2021)

@RobinHood centerquick‘s video claims an accuracy of 0.002” so mine isn’t wildly off.
I also found this video of a fairly nice DIY version. He uses a focusable laser from a laser level and says he can get a finer line.   I’m going to have to check the one in my junk box.


----------



## DPittman (Jun 21, 2021)

Nice job.  Yes I thought those gadgets looked useful but terribly over priced too.


----------



## combustable herbage (Jun 21, 2021)

I think if you had one that focused you could change that focal point and sharpen up the line, I am also curious of what angle you drilled the hole for the laser I am thinking if it is a smaller angle it would be better for keeping the circle smaller and a bigger angle would make the circle larger.  I think with a little playing you could find something that would work well in the normal range that you drill/mill, The one they are selling is universal so I think thats why they want so much but to me it would be more cost effective to make one for each machine you have.  It is definitely a handy idea.


----------



## Tom Kitta (Jun 21, 2021)

Best part is you can freely make copies and even sell them - they cannot patent it and if they did you can easily kill it with previous art. I.e. they themselves copied someone else's idea. See for example: 




and there are even detailed instructions how to make one:  https://www.instructables.com/Laser-Centreedge-Finder-for-a-Mill-or-Drill/

Here is actual inventor (probably) - 




I.e. its been around almost 10 years!


----------



## Johnwa (Jun 21, 2021)

I tried to drill the hole for the laser at about 14 degrees.  That would give me the smallest circle about 6-7 inches down.  Unfortunately the beam misses the spindle axis by about ¼” so the smallest circle is ½”.   If I make a final version I’ll make the angle adjustable.


----------



## Janger (Jun 23, 2021)

I think this is a job for a 3D printer. Model something up John!


----------



## Janger (Jun 23, 2021)

Tom Kitta said:


> Best part is you can freely make copies and even sell them - they cannot patent it and if they did you can easily kill it with previous art. I.e. they themselves copied someone else's idea. See for example:
> 
> 
> 
> ...



Gotta love Dan! That's a great video. 

I ordered the lasers to make one of these - it's on the endless project list!


----------

