Author Topic: Learning is a process  (Read 1962 times)


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Learning is a process
« on: January 06, 2018, 06:04:32 PM »
It has been a busy start of the year. Setting up the VFD and making some stuff. Bought a new motor for the lathe. It is a VEM motor which is explicitly designed for VFD use.

I have to apologize about the high speed steel. It appeared that the guy in the Frankfurt flea-market was actually lying about these. They are some sort of high grade steel but NOT HSS. Next time I will have a file with me ... or better yet, I'll borrow his.

I have been learning to adjust the 4-jaw chuck. After making the related tools it has been a joy. The magnetic dial stand is definitely NOT the way to go. It is not rigid and the reading will fluctuate. The magnetic stand collects all swarf and is really nasty to set up. I made a dial attachment for the tool-post. It is rigid and gives repeatable results. Another thing that helped with the 4-jaw set up was the two smalle keys for the chuck. The method of using two keys is widely show in diverse videos. Works for me too. The chuck keys are made of round wood with a large screw glued in. Cut off the nut and grind to fit into chuck. Looks nasty but works well and the wood gives a good grip.

Next thing was to make two arbors for the slitting saws. This was a learning process as well. The one in the picture was the third try which eventually succeeded. For threads I used M12 dice and tap. The hard part was the concentricity. The bore is 0.02mm oversize and the counterpart 0.02mm undersize. This was my first time ever with micrometers and snap gauges. Learning by doing.

Since I have the arbor and a bunch of slitting saws I did some experimenting. The one in the picture is by far the best when I have to cut something. Since the saw is carbide it can be ran really fast. I found out that the best speed is somewhere in the vicinity of 700RPM.

Tomorrow I will start learn single point threading. Made the insert holder. I am looking forward on this experience.

The lathe is NOT that good with threading. The thread pitch has to be set up by choosing suitable gears. Further more - it seems that this lathe cannot do left-hand threads as the feed direction cannot be changed. The motor in the picture might be able to drive the lead screw directly. Add a sensor to spindle, microcontroller and user interface -> presto - electronic gearbox.

Here are the images related to the above. For a really big picture, feel free to click these and have a cup of coffee while loading ....

Offline Peter Cordell

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Re: Learning is a process
« Reply #1 on: January 06, 2018, 11:32:05 PM »
Why did i not think of that  "chuck keys are made of round wood with a large screw glued in" so simple like many good ideas