- Joined
- Jan 7, 2016
- Messages
- 3,278
Right Aukai!? I was right there with you... From "Yippeeee, A new gadget for my shop" to an immediate balloon pop of "dangit, that looked soooo cool."
LOL
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Optical Center Punch
- Thread starter Weldo
- Start date
Right Aukai!? I was right there with you... From "Yippeeee, A new gadget for my shop" to an immediate balloon pop of "dangit, that looked soooo cool."
LOL
- Joined
- Jan 10, 2019
- Messages
- 1,042
"Not available online"Lee Valley Tools has them at $62.50 USAD. That's about $2.00 US
- Joined
- Oct 4, 2016
- Messages
- 7,023
Saw this one online
www.travers.com
TTC OCP1 1-15/16
ApplicationsEfficient precision punching of hole centers.FeaturesSuperior in accuracy to any tool of its kind, including those with cross hairs, because it presents an unobscured target to be punched.Tolerance of ±.001" can be easily obtained.Cross-hair 9X power magnification lens.
www.travers.com
- Joined
- Dec 20, 2012
- Messages
- 9,422
When I got mine, I used it a lot to try and get accurate with it. Admittedly, the Lee Valley one is nicely made but is it more accurate than the other methods I use? No. Is it faster? No. Is it worth the money? Yes, because it is a nicely made tool but from a utility standpoint, other ways are faster and as good or better. I suppose you could make it work better but for me, it just isn't worth the time.
- Joined
- Sep 7, 2019
- Messages
- 674
Update!
I ended up buying the one off @main_cogg. The optic was badly scuffed up on the end but I managed to re-work it a little. To be clear, I place no blame on anyone for the scuffs. I was aware that the tool was 25 years old and the plastic optic is VERY susceptible to scuffing.
I faced off the end and cut a small concentric ring in the face. I then put a small dot in the center with an 1/8" spotting drill. Here's a picture of it!
The chip you see at 4 o'clock is my fault. It's the result of impatience and carelessness. After facing I polished it with water and sandpaper from 400 to 2000 and finished it with automotive hand glaze rubbing compound. Came out pretty good.
I feel like parallax is a non issue. It's fairly easy to tell when your eye is centered with the optic. And on the topic of "bore play", as fun as that sounds, there is none to speak of. I haven't measured the bore, punch or optic but there is no perceivable play or slop in anything.
Maybe this thing is not for everyone but I think it can help me. I did a practice run by scribing some lines, using the optic and centering the intersection. I then pricked it with the punch and put the optic back in to double check. The prick was perfectly centered in the optic.
Seems like a pretty accurate way to make marks.
I ended up buying the one off @main_cogg. The optic was badly scuffed up on the end but I managed to re-work it a little. To be clear, I place no blame on anyone for the scuffs. I was aware that the tool was 25 years old and the plastic optic is VERY susceptible to scuffing.
I faced off the end and cut a small concentric ring in the face. I then put a small dot in the center with an 1/8" spotting drill. Here's a picture of it!
The chip you see at 4 o'clock is my fault. It's the result of impatience and carelessness. After facing I polished it with water and sandpaper from 400 to 2000 and finished it with automotive hand glaze rubbing compound. Came out pretty good.
I feel like parallax is a non issue. It's fairly easy to tell when your eye is centered with the optic. And on the topic of "bore play", as fun as that sounds, there is none to speak of. I haven't measured the bore, punch or optic but there is no perceivable play or slop in anything.
Maybe this thing is not for everyone but I think it can help me. I did a practice run by scribing some lines, using the optic and centering the intersection. I then pricked it with the punch and put the optic back in to double check. The prick was perfectly centered in the optic.
Seems like a pretty accurate way to make marks.
- Joined
- Mar 25, 2013
- Messages
- 4,617
Mine is a Mitutoyo 9x. It has a tiny dot in the center with a circle surrounding it. I have no trouble aligning it by placing the center point at the intersection of the scribed lines. Visibility is quite good. Weldo- you might consider making a replacement lens and using a tiny point in the center. Do you have some acrylic laying around?
Robert
Robert
- Joined
- Sep 7, 2019
- Messages
- 674
Yea, even the instruction sheet that came with the set mentions a dot and ring situation. The optic I received did have a cross hair but since a cross hair is not illustrated in the instructions it leads me to believe that the cross hair was made by someone as a later modification.
I agree that a cross hair would be a good reticle. I actually tried to reproduce it by carefully setting tool height and scratching a line with the cross slide. It didn't work out very well for me. I figured the dot and ring is more easily achieved accurately on a lathe so I went with that.
I think you are right about that. When I re did the reticle I used the smallest, stiffest drill I had but I must have fed too deep and the chisel still left a tiny flat spot. This is some super precise work to scratch in these lines/dots. If I revisit this I will maybe try chucking up a carbide sciber in the tailstock and simply making a prick mark in the center. I'll try out what I have for a while, if it doesn't work out I at least I know how to alter it. I figure I have enough length on the optic to face it off a few more times. I didn't want to try making one from scratch since I don't know the radius of the lens... I guess I could just copy the old one, right? Now I need to buy a set of radius gauges!
I agree that a cross hair would be a good reticle. I actually tried to reproduce it by carefully setting tool height and scratching a line with the cross slide. It didn't work out very well for me. I figured the dot and ring is more easily achieved accurately on a lathe so I went with that.
I think you are right about that. When I re did the reticle I used the smallest, stiffest drill I had but I must have fed too deep and the chisel still left a tiny flat spot. This is some super precise work to scratch in these lines/dots. If I revisit this I will maybe try chucking up a carbide sciber in the tailstock and simply making a prick mark in the center. I'll try out what I have for a while, if it doesn't work out I at least I know how to alter it. I figure I have enough length on the optic to face it off a few more times. I didn't want to try making one from scratch since I don't know the radius of the lens... I guess I could just copy the old one, right? Now I need to buy a set of radius gauges!