Thursday, May 15, 2014

Champion 77 Thread Lube Pot Liner

I am getting much more comfortable and skilled at using the 77, I have two pair of sandals completed so far.
However, I am and most likely will continue to use it about once a month and after cleaning and restoring the thread lube pot I realized that I simply will not leave the lube in the pot for weeks or months at a time. The lube drys slowly, thickens up to a syrup, and leaves a film all over everything.

I have been sucking out the unused lube with an ear syringe then cleaning and drying the pot but I thought that a liner would be the correct answer. It turned out to be an easy one day project that came out the 1st try.

I have a DIY vacuum form set up which is the ideal process to make this part.

1st I needed a pattern and decided to make a cast of the inside of the pot.
Two problems:
  1. Casting directly into the pot would require a release
  2. The pattern needs to be undersized to leave room for the plastic thickness.
I used an old die makers method of lining the mold (pot) with wax sheet which I happened to have from my plastic model making days. Its called Parafilm "M". By its self it is too thin 0.005" but that was OK because I could layer it and using the heat gun was able to get a nice thick lining, I was shooting for 0.030"






Next I mixed up some Bondo poured it in.





It popped out without hardly any effort! (I was shocked and worried)





I had to sand and put a finish coat of Bondo on it and then took it strait to the vacuum table without any finish or release on it.


Used some clear plastic from some packaging I scavenged and it came out perfect the 1st try (when does that ever happen?)





Yes it is fine, and yes I am obsessive compulsive!



2 comments:

  1. Tom: I have a champion 77 with a brass serial number plate N2240 which appears to be nearly identical to yours. However, mine was in a basement of a now deceased shoe repairman and seems to have not been cleaned in its last many years of usage thus it is pretty well frozen due to iron hard wax build up. So a couple of questions-- after a day of cleaning the wax pot is now visible but I cannot figure how it can be removed...is it simply slid on its two horizontal rods or is it somehow locked onto the bars by means I have not excavated to? 2nd question: the hand wheel is also frozen and it seems to be gear locked down in the cast iron bowels. Any suggestion would be appreciated- your blog is most valuable to me and very much appreciated.

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    Replies
    1. Hi, yes it does slide out on the two rods, nothing keeps it in except the thread feeding out, it slides without a lock.
      2 The hand wheel turns when the left foot pedal is depressed, when the left foot pedal is depressed you should hear a snap when the rod at the back goes up.
      The machine will "one stitch at a time"
      so you can make a single stitch with a single pedal press (you can hold it down) for continuous.
      I'm not at home now so i cant tell you what to look for but please keep me informed
      could you send pics?

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