Machining plastic gears question

1

In the interest of getting the sewing machines through more traumatic injuries I’ve decided I’m going to learn how to machine replacement plastic parts for them, using the small lathe or the CNC machine. Two questions:

  1. What kind of plastic is best for this?
  2. Do you know any good quality tutorials, books, or videos for learning the specifics of this kind of thing

I’m planning to start with these cams that make the old Kenmore machines do specialty stitches.

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And a note: 3d printing is not good for this because of material durability and the amount of detail

2

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This is a type of gear that I would like to be able to make

3

If you are going to make them, I’d probably use an epoxy. I’ve seen videos of that being used on lathes.

You might want to just try to see if the manufacturer of the sewing machines have the parts for replacement and purchase them.

4

The machine I’m currently working on for my personal project is a necchi 565, which was made in Italy in 1977 and was the last machine manufactured there before they moved production overseas. It is extremely rare and they do not work because the kind of plastic used for one specific gear became brittle and no one who is capable or cares has a functional replacement gear even to copy. This is my long term goal to replace after I learn the techniques.

I assure you I have thought about buying replacement parts from sewing machine manufacturers.

5

These sites might have the parts you need or may be able to help you find the parts you are looking for.

Central Michigan Sewing Supplies redirects here.

6

I know how to shop for sewing machine parts. They don’t even have the bobbin case my machine takes. I was hoping explaining that I know what I am trying to do and why would clarify that I don’t need unrelated advice.

It makes me feel like you think I’m completely incompetent and I don’t really appreciate it.

7

My apologies. I thought when you posted here you were actually asking for help.

My error. Good luck with your project.

8

I am asking for help with material selection and resources for learning various methods of tooling machine parts if anyone has recommendations on that I would appreciate it

9

Check out this YouTube. . .https://www.youtube.com/watch?v=hpxmwXlaKBg. I feel the critical step will be modeling the part. Note that the video used a resin printer and the resin they intend to use for the parts they will sell is ~$150 per liter.

10

@mgrossbauer This is great, thank you! I’ve watched through some of his repair playlists, I’ll watch this tomorrow and I think the sewing machine specific info will be helpful no matter how I actually end up manufacturing them.