Centering scope vs. laser center finder

[tlpriebe]

I am about to start my first model, and I am wondering which is the
best tool for precisely locating points on the casting to be milled or drilled -
the centering scope or the laser center/edge finder?  Thanks in advance for
your opinion.

[AOG]

I don't have a centering scope but I routinely use a laser. According to my DRO I am usually accurate to +\- .oo15 of an inch or about .4 mm.

Tony

[steamer]

On a casting....IMHO....neither

Get a "wiggler".       Most holes in finished parts start at a dimension from a finished edge....that being said....there's your datum and I would use an edge finder from that.

But with a rough cast edge, once you do your layout, you can pick up your layout lines with a wiggler pretty easily, and keep a bunch of money in your pocket for other things.     An exception is particularly small features,  like watch and clock work, where a centering scope is a nice thing to have, ...but they are expensive.

I can't speak to the laser as I don't own one , other than unless the beam spot is particularly small, I wonder about the positional tolerance you can achieve...especially on a rough surface that might be specular....The needle tip on a wiggler is smaller than a layout line...and with a simple magnifying glass,..you can get pretty darn close!


Edge finders and wiggler sets are all easily available, and pretty cheap and give good results ......unless you're making watches... 

[b.lindsey]

I agree with Dave here, find a datum and use an edge finder or wiggler. I don't own either a laser pointer or scope but they are less useful on the smaller Sherline equipment IMHO anyway. If I may ask, please post an introduction in the introduce yourself section so we can better welcome you to the forum (even though you joined a while back) and learn more of your interests and what you have in mind for that first exciting project. Hoping you will be willing to do a build log on it as well

Bill

[Vixen]

I would advise against a laser centre finder.  I imported one a well known one from the USA (at great expense) but could not get on with it. I sold it on as I much prefer a wiggler. 

A laser centre finder may be ideal for woodworking but not for metalwork.

The spot size of a LED laser is quite large. The spot size changes with the reflectivity of the metal. A refraction filter (supplied with the unit) will also reduce the spot size, but also reduces the brightness of the spot. To find an edge you place the spot half on and half off the edge. To find a centre mark you surround the mark with the laser spot. I always get better results using a wiggler or cylindrical edge finder.

That's my opinion, others may disagree.

MIke

[Stuart]

I totally concur Mike

Sold mine and use a point or wiggler

Stuart

[AOG]

I must be odd man out. I  love my laser once I learned how to use it properly. The key is that when you cross a scribed line or a punch mark the light refracts differently. You don't have to see the spot you just have to see the change. Put the laser on the change point and your on the spot.

Tony

[steamer]

Hey Tony,

To each his own, if it gets the job done, then it's the right solution!   


Dave

[bp]

I have been using a centering scope for several years.  It's very good, and requires no batteries or external power source.  I also use it for setting lathe tool height.  Mine was "on special" at ENCO in the US.  Postage to Australia wasn't an issue.  As far as I can tell it's very accurate, I cannot give a figure, but using a loupe on a spot drilled centre seems to indicate, to me at least, that it's spot on.
cheers
Bill