Thread: Machines for Straight Razor Production

Hey, everybody! I just thought to post some pictures I grabbed a few years ago while visiting a factory where straight razors are produced. We sometimes get to see little videos of these things in use, but seldom have the chance to look more closely at the details and so I thought to post these pictures to add to the general store of knowledge

This first image shows a razor grinding machine from the front. The blanks are inserted cutting edge upwards between the two grinding wheels and moved front to back to be ground, resting on that little support between the stones. All the while, a stream of coolant jets in from above to keep the razor blank from overheating and to flush away the slurry of stone and iron. The tray hanging off the front of the unit is for holding a number of razor blanks.

Here in the second image the coolant shroud has been removed and the machine stands revealed. The concept of these razor grinding machines is fairly simple. There are two parallel spindles which are adjustable in terms of distance from one another. A whole range of grinding stones of various grit weights and diameters can be mounted on the front of the spindles to handle the different steps in the blank-grinding process. The silver-colored hand wheels seen on the side of the machine are used to set the absolute distance of the stones, one to the other. That lever hanging down on the left side is used during the grinding process to subtly alter the distance between the stones.

In this third shot we are up a little closer to the business end of the machine. It should be noted that the razor support between the stones does not move during the grinding process. It is only reset between passes on groups of blanks and is thus moved up or down to accommodate desired changes in where the wheels meet the razor blank. Do note that the razor support is tipped with a brazed-on back of tungsten carbide as otherwise the constant sliding of the razor blanks in the wet, surrounded by stone slurry would wear it down in a relatively short amount of time. The wheel spindles run in simple metal bearings with enclosed grease cups providing the lubrication. As long as the operator remembers to occasionally give those grease fittings the occasional tightening turn to force in more grease then there will always be a positive displacement of grease away from the fittings which serves to keep stone dust out of the works.

The final picture of the grinding machine shows the drive system at the back. This is nothing more than a set of flat, leather belts running off of a jack shaft which is v-belted to an electric motor. Sharp eyes will notice by the way the flat belts attach to the pulleys that the spindles both rotate in the same direction. Yes, that is absolutely right and means that the grinding operation occurs with one wheel moving upwards relative to the razor blank while the other wheel is moving down!

I have read the ongoing questions and rants about what best to use as a good buffer and with what size of wheel. To that end, I thought to show the following images of one of the buffing machines used for razor production. Give an eye to the setup. That is one, honking large spindle driven at high speed by a fairly beefy electric motor. Again, the spindle bearings are fed by simple grease cups, but with the addition of some extra homemade shielding on the nearest the buffing wheel to help keep out the polishing dust.

Oftentimes the buffing wheels used on these things are really pretty small. Forget your 6” or 4” wheels. These things are smaller (and intentionally so) in order to polish properly within the smaller radius of the ground concave portions along the sides of the razor blank. The wheel you see in the image is something on the order of 2” to 2-1/2” (5cm – 7cm). Various materials are used for these small wheels, including cotton, felt and leather.

That's great, thank you. Any idea of the size of the grinding wheels? I've been thinking about building something along these lines.

Great pics.
Bruce

Thanks for the excellent pics and info, Ignatz!

I had always wondered about the relative rotation of the wheels in the grinding machine - now you have solved that issue! I suppose that the spindles rotating in the same diection mean that the upward motion of the side of the right wheel while the opposite side of the left wheel is going downwards serves to stop the blade from being grabbed or repelled during the grinding process.

The buffing machine was comforting to see - at least I now know that my 3" and smaller wheels are not verboten!

Thanks again,
Neil

There were a range of different grinding wheels for those machines. I did get a quick peek in the storage cabinet, but - sadly - at the time it never occured to me to actually measure their diameters. Remember, of course, that these machines are used for classic hollow grinding and not just the simple hollowing of a quarter hollow or half hollow grind. To that end there are multiple passes per blank with the need for different diameters across the face of the blank (all faired smoothly into each other). If memory serves (and I'm kind of guessing here) there was a range of something like 1-1/2" up to (maybe) even 4"... but please don't quote me on that. You can almost decide for yourself what diameters would be appropriate depending upon the width of your blank and what kind of grind you would want to end up with. I really wish I could have watched the razor grinders in action, but I had my tour of the factory on an off day (sigh!).

ignatz
many thanks for photos. Children the matter is that it is factory on which for change do many razors and it without such machine tool not to manage. And if you are going to do one razor it is completely not obligatory to you to do the machine tool on two wheels. Believe it very difficult, I already tried. I have stopped on the machine tool with one wheel, for manufacturing of the razor that that is necessary. I did all my razors on the machine tool with one wheel even my last razor with two diameters too is made on one wheel. I hope with my transfer clearly about what I write.

Great pics,thanks for posting them,OSHA would go batshit over stuff like that

Originally Posted by pixelfixed

Great pics,thanks for posting them,OSHA would go batshit over stuff like that

Could that be part of the reason why there are no major American razor manufacturers?

Thanks for the pics Ignatz. As a machine junky I always appreciate seeing things mechanical with motors The only thing that would have made those better is if they had been run by overhead gang shafts and wide leather belts. Oh ya!

Ray

KMG already have a reputation for being built like a tank (hopefully I'll have mine soon ) but this thing looks literally as solid as a tank.

As for OHSA, such machines are allowed in Europe, but only in certain circumstances.
Generally speaking, things like belt sanders and grinders are manufactured in such a way that no moving parts can be touched. This is for safety certification. Open machines are allowed if the purpose requires such, but then there are other safety requirements, such as operator training etc.

This is one of the reasons that KMG style machines are not available here.

Great stuff, thanks for sharing. It would be awesome to visit such a place. I too noticed how solid looking the equipment was...built to last generations.

what is the purpose of the 3 grooves seen in both right and left wheels?