Metric threads on a Myford super 7 with quick change gearbox?

[Keith ChartersParticipant @keithcharters25446]

Hi, novice here. I have a Myford Super 7 with a quick change gearbox, circa 1976. I also have a 34 tooth and 33 tooth stud gears which I believe can be used to cut ‘metric threads’, albeit with some small errors. I have the ‘standard’ quadrant, as supplied with the QC gearbox. I have the excel spreadsheet that indicates which stud gear to use in place of the standard 24t one but, when I remove the 24t stud gear I cannot install either of the 33t or 34t gears! I have loosened the quadrant but I cannot get enough movement to install the replacement gear! I wish to cut a 16mm x 1.5 metric thread so, as per the spreadsheet, I’m trying to install the 34t gear but, have failed miserably! Am I missing something or am I doing something wrong? Any help would be greatly appreciated!

[peak4Participant @peak4]

No, you’re not missing anything, don’t worry.

I had the same issue, so I extended the curved slot in the banjo/quadrant slightly with a round file.

In my case it was on a Warco 720 Super 7B clone, but I’ve read of others having a similar problem with the genuine Myford.

Once you’ve done the job, it makes cutting the threads easy.

Bill

[bernard towersParticipant @bernardtowers37738]

Not had a problem with mine and have been cutting/milling threads for a number of years

[Roderick JenkinsParticipant @roderickjenkins93242]

I had to tweak the quadrant on my S7 as well.

Rod

[egaParticipant @ega]

So did I.

And may I commend to you the simple modifications I made to allow the stud gears to be changed tool-free? I posted details of this some time ago but am blessed if I can find them now. Could re-post if there  is any interest in this.

[Author]

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