# Optical Center punch



## Tin Falcon (Nov 7, 2008)

Success finally
As many of you know an optical center punch of the Mark on type as sold by Enco and others is a great layout took. this especially goes for those of us who do not have a DRO on the mill. these critters sell for around $40 and up these days. 
Manny moons ago I decided to make one. Easy enough I thinks. Well made the body and the punch with not problem but a couple attempts still left me without a usable magnifier. 
I am not sure what went wrong I even found a reference on optics and did some calculations. I used polycarbonate for the lens they make safety glasses out of it so it should work. 
At some point I bought a piece of Lucite rod from Enco and it has sat in the stock rack. 
Well last night I took the rod lopped off a piece and made another attempt to make a lens no real measurement for the length and eyeballed the lens radius. 
Well low and behold I now have a shop made working optical center punch the lens is not perfect I may tweak it some but it works well enough to use. 
Seems like sometimes a project has to age a bit before it wants to be finished. 
Tin


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## ksouers (Nov 7, 2008)

Congratulations Tin.
I agree, sometimes letting things ferment makes everything come together. You can't force creativity, each solution has it's own timetable. It'll let us know when the time is right, and not a moment sooner.


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## wareagle (Nov 8, 2008)

Outstanding! As the old saying goes, never give up!!


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## CB750k8 (Nov 26, 2008)

Tin Falcon  said:
			
		

> Success finally
> As many of you know an optical center punch of the Mark on type as sold by Enco and others is a great layout took. this especially goes for those of us who do not have a DRO on the mill. these critters sell for around $40 and up these days.
> Manny moons ago I decided to make one. Easy enough I thinks. Well made the body and the punch with not problem but a couple attempts still left me without a usable magnifier.
> I am not sure what went wrong I even found a reference on optics and did some calculations. I used polycarbonate for the lens they make safety glasses out of it so it should work.
> ...


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## compound driver 2 (Nov 26, 2008)

Never found a need for an optical center punch. If your scrive lines are visable and evenly deep and the center punch ground correctly the tip of the punch should drop into the cross formed by the scrive lines.


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## Maryak (Nov 26, 2008)

Tin,

Good news on the centre punch. Just shows again that genius is 10% inspiration and 90% persistence and perspiration. 
	

	
	
		
		

		
			





Best Regards
Bob


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## itowbig (Nov 26, 2008)

ok so where are the plans for this : & lets not forget the all important pics ;D
yes were a finicky bunch ;D we got to have our pics ;D


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## minerva (Nov 26, 2008)

hi all,
for anybody who aspires to the making of an optical punch may I highly recommend 
a visit to John Moran's (aka gadget builder) site where all is revealed
http://www.gadgetbuilder.com/index.html

I am waiting for delivery of some silver steel to complete the punch side of things.
The optic, following John's advice proved to be relatively straightforward and the first attempt produced a successful result ( see attached photos ). I will say that I used a ball turning tool (again one of John's designs )
to achieve a 9/16 Radius on the optic. If any one particularly wants any dimensions just shout.
Kindest Regards.

Terry t

ps sorry for photo quality I really must see if Santa can help out ( new camera hint hint! )


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## dparker (Nov 26, 2008)

Hello All: I made my optical center punch a few years ago after reading a article in HSM or MW.
I used a piece of clear 1/2" Dia. acrylic rod (from Tap Plastics) and squared off the working end and turned two very shallow circles into the end. The other end was filed to a slight crown and the both ends were polished with a plastic polishing compound. A cotton ball was used to hold the polish and I kept rotating it to help form and polish the crown.
The first one I made had too much magnification so the second one was a much shallower crown. The block is made of aluminum and would do better if I get around to gluing on some gasket material or thin rubber sheet on it to keep it more stable from slipping on the parts.
















The amount of light going through the rod is surprisingly good enough to be able to see quite easily where you are, and the circles do a good job over a center punch or scribed line intersections. 

The pictures are taken on a tablet of 1/4" per square paper if anybody is interested in the dimensions, although this could be made to any dimensions desired.
don


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## John S (Nov 26, 2008)

To stop mine slipping it has a groove in the base with an 'O' ring super glued in.


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## black85vette (Feb 13, 2009)

Anyone else use one of these? What are your thoughts on them?


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## John S (Feb 13, 2009)

Brilliant,
I use mine about as often as I use my white stick.

JS


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## Maryak (Feb 13, 2009)

black85vette,

This topic is already here - http://www.homemodelenginemachinist.com/index.php?topic=3290.0

At the top of the page is a search function. If you enter your search parameters when you are looking at the index [HOME]. page this will search the forum. Elsewhere it will only search within the board you are looking at.

Best Regards
Bob


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## David Morrow (Feb 14, 2009)

I love mine and use it all the time.

And to hell with the search function. Whenever a new guy asks a questions, the old guys just point to the Search function. Ask old questions and get a whole new set of answers is my opinion. The search function is useful but it can stifle new discussion on old topics.


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## Blogwitch (Feb 14, 2009)

David,

Rather a bold statement.



> And to hell with the search function.



And deny the newcomers the mine of information from previous discussions. It doesn't stifle, but enhances, as new discussions might not have the same knowledge base available as previous ones.

http://www.homemodelenginemachinist.com/index.php?topic=2870.msg32704#msg32704

http://www.homemodelenginemachinist.com/index.php?topic=661.0

Topics should be expanded, not restricted as you suggest.

By just using these two examples, it might resurrect old posts or stimulate further discussions.

The search function is the most important feature of any forum. Allowing access to a wealth of information, rather than who is on line and interested in the subject at this moment in time.

Blogs


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## Maryak (Feb 14, 2009)

Blogs,

I have been pondering on the best way to respond to David Morrow's post. You have done it much better than I could have. :bow:

Thank you and Best Regards
Bob


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## black85vette (Feb 14, 2009)

Thanks. Actually I did search before I posted. Been around forums (and bulletin boards before that) for some time now. The other posts dealt with using the punch and making one.  I was more interested in a general discussion of how commonly they were used and different views on them. I found it interesting that one of my best friends has been a machinist in a tool and die department for 30 years and had never seen one until I took mine over to his shop.

So, back to the discussion on the optical punch.


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## Metal Mickey (Feb 14, 2009)

I wouldn't be without mine! It really impoves my ability to centre punch on the mark required. Buy one, you won't be dissapointed. Mike


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## BobWarfield (Feb 14, 2009)

I'm with David. Telling newcomers they have to search instead of answering their question is something those "other" forums do all too often. 

It implies the newcomer is wasting your time by asking the question. If a friend asked me a question I knew the answer to, I would be very unlikely to refuse to answer his question and instead school him on the use of Google. If a friend gave me that answer, I'd consider it rude and he'd better be pulling my leg.

And, as black85vette pointed out, he was already familiar with search and had used it.

Best,

BW


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## PhillyVa (Feb 14, 2009)

How about giving an answer and a link for more info...that would work for me.

Regards

Philly


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## chuck foster (Feb 14, 2009)

i use my optical center punch almost every day, at work and in my home shop. it is great little tool that is easy to use and cheap to buy.


chuck


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## putputman (Feb 14, 2009)

I guess I am another one of those odd ones. I've been a tool & die maker for over 50 years & I have never seen one or even heard of an optical center punch until this post. ???  ???  ???


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## Stan (Feb 14, 2009)

I have some serious vision problems and one of them is that my eyes don't focus properly. It is impossible for me to set a punch on a crosshair now. The optical center punch is the answer for my problem.


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## shred (Feb 14, 2009)

I haven't got one and don't feel very left out. If I had one, I'd only use it occasionally since I don't often do traditional layout type things.

That said, I'm an expert on some other forums and it can get very tiresome when the same question is asked over and over again. After a while the experts just quit responding. I know this forum guidelines are that questions shouldn't be answered with just "do a search", but sometimes that's the best answer. If you have done one, say so up front.

The advantage of adding to an appropriate existing thread versus starting a new one is the information is consolidated in one place for the next person that does go looking for it-- they don't have to read a dozen topics that have largely the same content. Links back to appropriate topics are also good.


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## Brian Rupnow (Feb 14, 2009)

Before I joined this forum, I had never heard of an optical center punch. I was very intrigued by the discussions on this forum, but I still couldn't figure out exactly what an optical center punch actually was. I went up to a tooling supply house and seen one first hand, and yes, they are a nifty device. I may buy one.---Brian


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## Metal Mickey (Feb 15, 2009)

I must admit I am confused about the debate on answering questions? If an 'expert' doesn't want to reply rather than tell someone to search google, then he or she, doesn't even need to reply, as there will certainly be someone on this forum who will be more helpful.


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## Foozer (Feb 15, 2009)

All roads lead to Rome, it is the path towards the destination that brings adventure

Destination, Center Punch mark; Path, Horse and Buggy or Batman Tool Belt


One of my favorite tools is the optical centre punch, worth its weight in gold!
http://www.homemodelenginemachinist.com/index.php?topic=2870.msg32704#msg32704

It is an optical centre finder, made by an American company, and as useful as a bowler hat with sleeves.
http://www.homemodelenginemachinist.com/index.php?topic=661.msg4181#msg4181

(basic complaint was the magnetic nature of this particular item)

With mild steel its better to let the center punch drop into the scrive lines.
http://www.homemodelenginemachinist.com/index.php?topic=661.msg4226#msg4226


All roads lead to Rome, younger days the scribe line methods worked fine. Could actually see detail and the sense of touch wasnt affected by the cooler climate of this area. Great Northwest my A%$ ! Optical punch, it, in my case at least combines the locating the punch to the scribe line intersection and subsequent checking that I actually am on the mark by using a magnifying glass to visually double check before applying the whack

So before I journey to a new destination I usually Search out what those before me have to say and put on my tall boots before I step onto the road before me.


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## shred (Feb 15, 2009)

Metal Mickey  said:
			
		

> I must admit I am confused about the debate on answering questions? If an 'expert' doesn't want to reply rather than tell someone to search google, then he or she, doesn't even need to reply, as there will certainly be someone on this forum who will be more helpful.


You would think so, but often no. In that field rumor and "I heard from ... " abounds and is usually incorrect. 
The people that ask reasonably intelligent, researched questions (even newbie Q's) get world-class advice. The others, not so much.

You can only give so many people a fish before you become tired of fishing.


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## black85vette (Feb 17, 2009)

The little light just came on. 2 posts prior did a search on "centre punch" and I only searched on "center punch"!  Guess you miss half the posts if you forget that Canadians, Aussies, and British have odd spelling of some words.


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## mklotz (Feb 17, 2009)

black85vette  said:
			
		

> ... Canadians, Aussies, and British have odd spelling of some words.



Careful there, vette. I think you'll find that the British, etc. have properly retained the original French spelling of words like centre, theatre and cheque. It's we lot who have buggered up the spelling.


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## John S (Feb 17, 2009)

mklotz  said:
			
		

> Careful there, vette. I think you'll find that the British, etc. have properly retained the original French spelling of words like centre, theatre and cheque. It's we lot who have buggered up the spelling.



Amongst other things  :bow:

JS.


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## mklotz (Feb 17, 2009)

Gimme a break here, Sir John. It's not like we invented the Reliant or something appalling like that.


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## rleete (Feb 17, 2009)

Ouch! That one's gonna leave a mark.


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## John S (Feb 17, 2009)

mklotz  said:
			
		

> Gimme a break here, Sir John. It's not like we invented the Reliant or something appalling like that.



Not only that but we invented the Heavy Goods reliant as well







 :big:

JS.


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## malcolmt (Feb 17, 2009)

Hi All

John S, 

TOUCH'E thats a fine looking craft isn't it. 

Reminds me of a scammell on a diet :big:

Kind regards

Malcolm


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## Brian Rupnow (Feb 17, 2009)

If I had a million dollars, I'd buy you a K-car---
A nice Reliant automobile---


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## Bernd (Feb 17, 2009)

John Stevenson  said:
			
		

> :big:
> 
> JS.



Did they ever find any of those three wheeled thingies laying on their sides after going around a sharp curve? I assume not since it dosen't look like it could get up any great speed. Just curious. 
Tri-cycle style vehicles are noted for tipping over in a sharp turn.

Bernd


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## mklotz (Feb 18, 2009)

Gee, Bernd, from the picture I thought it was lying on its side. 


To paraphrase Oscar Wilde, who always had such good things to say about the English...

The Reliant looks as if it was designed by someone who had frequently heard of automobiles but had never actually seen one.


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## rickharris (Feb 18, 2009)

Brian - In the spirit of the site - Make one - here is a link http://www.gadgetbuilder.com/OpticalPunch.html


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## rickharris (Feb 18, 2009)

Nothing wrong with Reliants - had this for 9 years never let me down.


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## ksouers (Feb 18, 2009)

I kind of preferred the Reliant that Jeremy Clarkson, et al. sent up on a rocket a while back.

It was a most spectacular crash ;D


Kevin


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## mklotz (Feb 18, 2009)

Yes, Reliants being forcibly removed from the surface of the earth. It's an idea whose time has come!


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