2023 Author: Bryan Walter | [email protected]. Last modified: 2023-05-21 22:24
In the last episode of our saga, devoted to how amateur designer Alexei Bragin restores an electron microscope in his garage, we talked about the importance of turning and about the first small machines on which the author of the blog learned to work. In a new episode, this conversation continues: now Alexei has to master two more machines: a milling machine and a large lathe.
NGF milling machine
What if you need to make a part that is not a solid of revolution? Or just make a plane on a part / workpiece? In the project "Electron Microscope" we will definitely need this. A milling machine comes to the rescue. We also start with a small one, and connoisseurs know it by three letters of NGF: Desktop Horizontal Milling Machine. Milling machines are vertical and horizontal, according to the location of the spindle axis. I must say right away that horizontal ones are quite specific, and in most cases a vertical router is required. NGF is universal - it turns from horizontal to vertical with the help of a special head. Now you will see everything for yourself.
This machine is educational, there were a lot of them in the labor classes of Soviet schools. Therefore, I managed to buy a completely new machine that had stood for many years. Unfortunately, I did not take a photo right after the purchase. New - it means that there are no worn parts in it, but there are enough poorly trimmed parts. The machine was painted with a dull light green paint, inside - century-old dust and petrified grease. We disassemble everything into parts, skin, paint, grease again.
But the machine is educational, that is, it is intended for training, and not for real affairs. Need to be finalized!
- We change the bearings in the VFG (vertical milling head) to more modern ones, we lubricate everything with good grease;
- we disassemble the longitudinal and transverse feeds, install the rolling bearings there so that everything rotates easily and naturally (before that, everything was based on friction there, and due to the lack of automatic feed, the milling process became too tedious);
- we make a new running shaft, which is responsible for movement along the Z axis. This allows you to expand the boundaries of the table downward movement (and this is, oh, how it is needed in this machine);
- we adjust the WFG to the bed so that there is no backlash;
- we buy and install a modern collet chuck with a set of collets from 2 to 20 millimeters.
Today the machine is in the following state:
This router has already helped out more than once and continues to help out in difficult situations. A lot of interesting things have been done on it, which in due time I will tell in more detail.
On a Swedish lathe, I gained invaluable hands-on experience (see the previous episode). But this machine has a limit of possibilities. The cones (so necessary for KF flanges) cannot be sharpened without an additional device, the stainless steel cannot be processed, it is too hard for him, titanium cannot be sharpened either.
Everything is convenient, small in size, accurate and clear, but … In general, I began to slowly look at larger machines, read about IL and others. I didn't look for anything purposefully, I just followed the offers. And once I read on the forum that the guys brought the C1E61VM lathes from the vocational school and are selling them at the price of scrap plus a small reward for delivery to Moscow and work.
There were about ten machines or even more, and they were really sold out like hot cakes. We arrived and looked. Yes, the machines are in a row, the state - yes, scrap metal. Battered, bent during loading, incomplete in places. I walked back and forth for a long time, twisted the knobs, of course everything stuck due to the fact that I experienced a strong deformation.
And then the attention was attracted by the most nondescript of all copies. Rusty, with peeling paint, but completely complete, including the cartridge. The guides are not worn out, although they are touched by corrosion. And the most important thing is that it is not broken anywhere. The caliper is in place, the tailstock is in place, a thick layer of oil has protected important parts from corrosion for decades. And he decided to take it.
This is how he was at the moment when he was just brought.
And this is what it turned into in the garage:
It also had to go through everything. Oil station, gearbox, gearbox. Replaced all bearings in the headstock. The most important spindle bearing was touched by rust, but even so, the accuracy did not suffer, but there was a problem in excessive noise. In any case, now all this has been replaced by bearings of the same class. The same had to be done with the machine apron. A number of minor problems were fixed, due to which, apparently, this machine was not used much for its intended purpose. For example, busting did not work, longitudinal feed did not turn on, etc.
Our main project is a microscope, so I will not talk in depth about the restoration of machine tools here, those who wish can contact me personally through the mail of the site.
But I'll show you something. For example, here's what the old three-jaw chuck of increased accuracy is capable of (on the indicator, the rightmost significant digit is microns):
So, it's time to use metalworking machines for their intended purpose and grind out everything you need for a microscope, and then try to connect a foreline pump and see what happens. Read about it in the next episode of our blog.