Grizzly Industrial H5781 - Optical Punch Set

Yes expensive but you try and make one. Was worth it to me. It will be worth it to anyone who worries about the hole being drilled in the right place. Like building a ic engine from scratch.

I decided to search the internet for a solution that would locate my center punch where I wanted it. I entered "optical center punch" and eureka! a hit . The design is very ingenious in that it captures ambient light and sends it down the base to illuminate a circle or a cross hair. It also magnifies the view which is hand for folk like me. I I apply a bit of pressure eo ensure the base does not move while replacing the optics with the punch. I wish that I discover this device 30 - 40 years earlier. I have not tried it on curved surfaces but it probably before I encounter the need. I chose Grizzly as the vendor because of their reputation of giving good service.

Could use variety of materials for the base that may be replaced possibly, for oil environment, but this one works fine in oil so far. Needs a few adapters or sleeves for fitting into tighter areas, while still remaining flat to whichever surface you want. An "aperture" that projects a flat bar onto an nearby adjacent or vertical surface while working on a horizontal surface as an example. The heart of the product should be a sleeve that nest into the whole thing, eliminating much of the space and providing winged or one wing base support, or raised leg base options as a few examples, not to mention a smaller base plate option for tighter areas, without the extra storage hole. Could use a leg stand for positioning around or over welds while being able to set over holes without having to grind them first and destroying the clues about the perimeter of the area to target. Obviously the user may have to adjust the height of the Lense in that case, so the upper support may have to be partially recessed or drilled. Also, the storage is bulky and not imaginative, or convenient for the on the road long distance worker that gets calls from far away and has to compact their tool selection.

Very high accuracy easily achievable by the novice for hole location. This item added to simple layout tools and a drill press makes near machinist quality hole patterns achievable with very little equipment.

On my set the base and the optical inserts are pretty good. The cross hair and the circle/dot are pretty well centered, though the line widths are very thick. The inserts and the punches have pretty good fit to the base holes.The problem is the punch tips are poorly ground, I measure over 0.01" total runout of the tips. It looks like these were ground by hand! Or maybe in a handheld arbor against a grinding wheel. Certainly not with a toolpost grinder. I touched them up on my lathe with a toolpost grinder.The way to see if the inserts and punches are centered is simply use the set - if the insert index marks stay on one spot while rotating the insert, it is good. If the index mark is centered on the punch marks, good set. If the punch marks are offset from the insert index crosshair, like mine, then you might want to exchange and see if you get a good set. Or it's a simple fix if you have a lathe and toolpost grinder.If the punches were ground right, I'd have given the set 4 stars. This set was made in India.

My vision is not what it once was. This device allows exact center punching exactly where you intended. Easy to use, works great.

This optical center punch has several issues that compromise its usefulness. I am planning to return it and buy a used name-brand optical center punch instead.First, the tool itself:1. The cross-hair is not well-centered. When I center it on a cross of scribe marks and rotate it by 90, 180, and 270 degrees, the center of the cross-hair wanders by about 0.010". The bulls-eye is better and does not wander nearly as much.2. Both optical inserts are loose enough to move by about 0.005" when touched.3. The lenses of the optical inserts have surface imperfections that distort the image in some locations. This is not a big issue for use, but it speaks to the marginal quality of the product.4. The holes in the base are reamed but do not have uniform diameters: both punch inserts stick as you push them the bottom of either hole. It is not always possible to feel whether the point of the punch is in contact with the work piece.5. The bottom surface of the base is lined with a hard rubber, which is nice. However, it does not prevent the base from sliding well enough. A concentric pair of O-rings would accomplish this much better.Second, the case:6. The set comes in a standard blow-molded case. However, this case is practically unusable, and not only because the two halves don't mate well when closing. More problematic is that the base, the punches, and the optical inserts are intended to be held in place by appropriately sized cut-outs in the bottom foam layer. But the base is much higher than the inserts, which lie flat, and the top piece of foam is far enough to accommodate the height of that base. This means that both the punches and the optical inserts rattle around in the closed case when it is flipped, allowing the punches to mar the plastic inserts. This is prevented during shipping by two separate foam pieces that hold all inserts in place - but it that is not workable for longer-term use.In fairness I should mention that the finish on the base and especially the punches is very good. But that does not overcome the much more serious issues above.

Product was covered in scratches within a cardboard box. Built cheap with all the china grease. Buy something else!