Laser edge finder

[don-tucker]

Has anyone had or used one of these http://cgi.ebay.co.uk/Laser-Edge-Ce...662?pt=LH_DefaultDomain_3&hash=item45f3b6b476
I have the chance of one as a Christmas prezzi and wondered how good or bad they are.
Don

 

[metalmad]

I dont know about any body else but im lucky to get some socks or undies in my christmas stocking so it looks bloody good to me ;D
cheers pete

 

[don-tucker]

All down to being a good boy,Pete
Don

 

[gbritnell]

I believe there was quite an extensive discussion on the Home Shop Machinist forum. It was quite awhile ago so you'd have to do a search.
gbritnell

 

[don-tucker]

Looked at old posts and came to the conclusion that it is not worth the extra cost,so I will go for an imperial electronic edge finder,The wife will be saving some cash here,have to think of something to go with it ;D
Don

 

[mh121]

I bought one of these quite some time ago. I can honestly say that I do not use it much, I tend to use my starret edge finder most of the time, in conjunction with my DRO centre facility. Saying that it does have its uses, like picking up on cst parts and hole centre pops.

Cheers,
MartinH

 

[Paolo]

Hello
I have built two of this, one point and the second with cross and interchangeable pointer for few dollars buying the laser pointer from China...It very useful especially for align the vise and centering the hole...

 

[Orrin]

I have one and don't use it. Mainly, it does not "amplify" or "magnify." To explain:

With the rotating Starrett contact edgefinder, at the instant of contact after an approach movement of a half-a-thou is amplified into the very obvious "kick" movement. No such amplification occurs with the laser edge finder.

I have a Starrett, an electrical and a laser edgefinder as well as an optical center finder that sometimes doubles as an edgefinder. The Starrett and the optical unit get the most use, by far. The optical is expensive; but, with its high magnification there is no doubt that I'm within a few tenths of a thou. IMHO they're well worth the expense.

I'm still trying to find a use for the laser, but it eludes me, so far.

Orrin

 

[mklotz]

I find it a bit off-putting that the ad pointed to in Don's original post makes no mention of accuracy of edge location.

I saw this unit at the Visalia show mentioned in the ad and the spot was disturbingly large. Also consider that a conventional edge finder will locate to the rotation axis of the machine, something the laser unit will not do.

 

[don-tucker]

Glad i posted this,I would hate for the misses to spend £80 and not be happy with it.I thought it would have been the dog's b-----
Don

 

[ruzzie]

I have had mine for nearly 6 yrs now and its been brilliant, with a little practice I have been able to quickly pick up an edge to within +/- .001" and now with the polarizer I can get rid of the fuzzy's from the dot .
I have had some issues with the switch and it is deadly on batteries if you forget to turn it off and it makes setting up to a scribed lines or center pop in the lathe a breeze.

Paul

 

[firebird]

Hi
Don

I agree with Paul, they are brilliant. I have had mine for about 2 years now and use nothing else. Before the laser I had one of the electronic touch type of edge finder. Not bad until a lapse of concentration and I wound the table the wrong way and bent it!!! They do need the polarizer though to get a really clean dot. The best thing is of course you don't have to do any calculations or halve the reading, where the dot is that's where you are. If mine went wrong or was lost I would buy another straight away.

Cheers

Rich

 

[don-tucker]

How accurate are they Rich ? does it not depend on the size of the dot,got me thinking now.
Don

 

[PaulG]

Very nice for tight spots. This is with the lens off, so the camera can see it, very small.

 

[firebird]

Hi Don

As accurate as I have ever needed to be, definitely within .001. An example of a job I carry out regularly is a piece of round bar that needs to be cross drilled. Hold the bar horizontally in the mill vise. Move the table so that the red dot is on the workpiece and then move the table until the dot goes off the edge and can be seen below. A bit of white paper on the table sometimes helps. Zero the dial and move the table in the opposite direction until the dot goes off the opposite edge and note the reading. Half of that is the centre of the bar. I have DRO fitted to both my mills. If for example I have a piece of 1/4 round in the vise and carry out the above procedure the DRO will read .250 to within a .001. thats how accurate I can get it.

Cheers

Rich

 

[don-tucker]

You guys have got me in a fix now,it seems 50-50 for and against,been looking for an electronic finder with smaller than 20mm shank,ideally I would like an imperial one with 5/8 or 1/2" shank.How about this ,I know it's not imp.but you can't have every thing.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=230550702523&ssPageName=STRK:MEWAX:IT
Then again the Starrett mechanical one seems ok. :'(
Don

 

[firebird]

Don

That's similar to the one I have. You have to be very careful when you approach the work piece, slowly and gently doe's it. If you then wind the table the wrong way (like I did) it's easy to bend it enough to make the tool useless. Perhaps that's just me being clumsy but it's worth remembering if you take that route.

Cheers

Rich

 

[Orrin]

I think I have an advantage, here, seeing as how I own and have used both the optical and the laser type. The optical unit shows me how inaccurate a drill chuck can be.

Every time it is used, the optical is easily zeroed in order to find the center of spindle rotation. On the other hand the zeroing of the laser is cumbersome, at best. This isn't a huge problem with edge-finding because one can use collets for that chore; but, for drilling things become awkward.

One can cope with this by making certain that the laser is mounted in the drill chuck exactly the same, every time. I usually do so when using the optical unit; but, on fussy jobs I re-check the zero every time.

I'd wager that the pro-laser crowd would be surprised how inaccurate their un-magnified zeroing is if they followed it up with an optically magnified examination of their set-up.

I guess it all boils down to how accurate one wants to be.

My 2¢

Orrin

 

[don-tucker]

Sorry to keep on with this thread,but at the moment I use a 1/4" dowel so almost anything is better,I like the idea of the Starrett as it has a dowel type end so better to locate on a round job,and looking at it being used on utube it would appear to be quite positive also less chance of damage,if I can get within a thou. I would be happy.
Don

 

[deverett]

I use a home made edge finder to the 1970s GHT design and it is accurate enough for my needs.

Have a look at Joachim Steinke's ball bearing edge finder. Seeing the quality of his work, I would imagine that if the simple design is good enough for him, it would be good enough for the majority on this forum. Now, if you want to go out and spend money, and Christmas time is approaching, well, that is a different matter.

Dave
The Emerald Isle